added support for a few middlewares, added match_domain option, changed index reference prefix from $ to #, etc.

.github/workflows/docker-image.yml

@@ -130,3 +130,18 @@ jobs:
               run: |
                   docker tag ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ steps.meta.outputs.version }} ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest
                   docker push ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest
+    scan:
+        runs-on: ubuntu-latest
+        needs:
+            - merge
+        steps:
+            - name: Scan Image with Trivy
+              uses: aquasecurity/trivy-action@0.20.0
+              with:
+                  image-ref: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest
+                  format: "sarif"
+                  output: "trivy-results.sarif"
+            - name: Upload Trivy SARIF Report
+              uses: github/codeql-action/upload-sarif@v2
+              with:
+                  sarif_file: "trivy-results.sarif"

Dockerfile

@@ -9,15 +9,15 @@ COPY src/go.mod src/go.sum ./
 
 # Utilize build cache
 RUN --mount=type=cache,target="/go/pkg/mod" \
-    go mod download
+    go mod graph | awk '{if ($1 !~ "@") print $2}' | xargs go get
 
-# Now copy the remaining files
+ENV GOCACHE=/root/.cache/go-build
-COPY src/ ./
 
 # Build the application with better caching
 RUN --mount=type=cache,target="/go/pkg/mod" \
     --mount=type=cache,target="/root/.cache/go-build" \
-    CGO_ENABLED=0 GOOS=linux go build -pgo=auto -o go-proxy ./
+    --mount=type=bind,src=src,dst=/src \
+    CGO_ENABLED=0 GOOS=linux go build -ldflags '-w -s' -pgo=auto -o /go-proxy .
 
 # Stage 2: Final image
 FROM scratch
@@ -28,7 +28,7 @@ LABEL maintainer="yusing@6uo.me"
 COPY --from=builder /usr/share/zoneinfo /usr/share/zoneinfo
 
 # copy binary
-COPY --from=builder /src/go-proxy /app/
+COPY --from=builder /go-proxy /app/
 
 # copy schema directory
 COPY schema/ /app/schema/

Makefile

@@ -1,4 +1,4 @@
-.PHONY: all build up quick-restart restart logs get udp-server
+.PHONY: all setup build test up restart logs get debug run archive repush rapid-crash debug-list-containers
 
 all: debug
 
@@ -9,7 +9,8 @@ setup:
 
 build:
 	mkdir -p bin
-	CGO_ENABLED=0 GOOS=linux go build -pgo=auto -o bin/go-proxy github.com/yusing/go-proxy
+	CGO_ENABLED=0 GOOS=linux \
+		go build -ldflags '${BUILD_FLAG}' -pgo=auto -o bin/go-proxy github.com/yusing/go-proxy
 
 test:
 	go test ./src/...
@@ -29,6 +30,9 @@ get:
 debug:
 	make build && sudo GOPROXY_DEBUG=1 bin/go-proxy
 
+run:
+	BUILD_FLAG="-s -w" make build && sudo bin/go-proxy
+
 archive:
 	git archive HEAD -o ../go-proxy-$$(date +"%Y%m%d%H%M").zip
 

config.example.yml

@@ -1,36 +1,64 @@
 # Autocert (choose one below and uncomment to enable)
-
+#
 # 1. use existing cert
+#
 # autocert:
 #   provider: local
-#   cert_path: certs/cert.crt # optional, uncomment only if you need to change it
+#
-#   key_path: certs/priv.key # optional, uncomment only if you need to change it
+#   cert_path: certs/cert.crt         # optional, uncomment only if you need to change it
-
+#   key_path: certs/priv.key          # optional, uncomment only if you need to change it
+#
 # 2. cloudflare
+#
 # autocert:
 #   provider: cloudflare
-#   email: # ACME Email
+#   email: abc@gmail.com                            # ACME Email
-#   domains: # a list of domains for cert registration
+#   domains:                                        # a list of domains for cert registration
-#     - x.y.z
+#     - "*.y.z"                                     # remember to use double quotes to surround wildcard domain
 #   options:
-#     auth_token: c1234565789-abcdefghijklmnopqrst # your zone API token
+#     auth_token: c1234565789-abcdefghijklmnopqrst  # your zone API token
-
+#
 # 3. other providers, check docs/dns_providers.md for more
 
 providers:
+  # include files are standalone yaml files under `config/` directory
+  #
   # include:
-  #   - providers.yml # config/providers.yml
+  #   - file1.yml
-  #   # add some more below if you want
-  #   - file1.yml # config/file_1.yml
   #   - file2.yml
+
   docker:
-    # for value format, see https://docs.docker.com/reference/cli/dockerd/
+    # $DOCKER_HOST implies environment variable `DOCKER_HOST` or unix:///var/run/docker.sock by default
-    # $DOCKER_HOST implies unix:///var/run/docker.sock by default
     local: $DOCKER_HOST
+
     # add more docker providers if needed
+    # for value format, see https://docs.docker.com/reference/cli/dockerd/
+    #
     # remote-1: tcp://10.0.2.1:2375
     # remote-2: ssh://root:1234@10.0.2.2
-# Fixed options (optional, non hot-reloadable)
+# if match_domains not defined
+# any host = alias+[any domain] will match
+# i.e. https://app1.y.z       will match alias app1 for any domain y.z
+#  but https://app1.node1.y.z will only match alias "app.node1"
+#
+# if match_domains defined
+# only host = alias+[one of match_domains] will match
+# i.e. match_domains = [node1.my.app, my.site]
+# https://app1.my.app, https://app1.my.net, etc. will not match even if app1 exists
+# only https://*.node1.my.app and https://*.my.site will match
+#
+#
+# match_domains:
+#   - my.site
+#   - node1.my.app
 
+# Below are fixed options (non hot-reloadable)
+
+# timeout for shutdown (in seconds)
+#
 # timeout_shutdown: 5
-# redirect_to_https: false # redirect http requests to https (if enabled)
+
+# global setting redirect http requests to https (if https available, otherwise this will be ignored)
+# proxy.<alias>.middlewares.redirect_http will override this
+#
+# redirect_to_https: false

docs/docker.md

@@ -74,7 +74,7 @@
 | `proxy.stop_timeout`     | time to wait for stop command                                                                                                                                       |                                | `10s`                       | `number[unit]...`                                                         |
 | `proxy.stop_signal`      | signal sent to container for `stop` and `kill` methods                                                                                                              |                                | docker's default            | `SIGINT`, `SIGTERM`, `SIGHUP`, `SIGQUIT` and those without **SIG** prefix |
 | `proxy.<alias>.<field>`  | set field for specific alias                                                                                                                                        | `proxy.gitlab-ssh.scheme`      | N/A                         | N/A                                                                       |
-| `proxy.$<index>.<field>` | set field for specific alias at index (starting from **1**)                                                                                                         | `proxy.$3.port`                | N/A                         | N/A                                                                       |
+| `proxy.#<index>.<field>` | set field for specific alias at index (starting from **1**)                                                                                                         | `proxy.#3.port`                | N/A                         | N/A                                                                       |
 | `proxy.*.<field>`        | set field for all aliases                                                                                                                                           | `proxy.*.set_headers`          | N/A                         | N/A                                                                       |
 
 ### Fields

schema/config.schema.json

@@ -37,7 +37,13 @@
           "title": "DNS Challenge Provider",
           "default": "local",
           "type": "string",
-          "enum": ["local", "cloudflare", "clouddns", "duckdns", "ovh"]
+          "enum": [
+            "local",
+            "cloudflare",
+            "clouddns",
+            "duckdns",
+            "ovh"
+          ]
         },
         "options": {
           "title": "Provider specific options",
@@ -56,7 +62,12 @@
             }
           },
           "then": {
-            "required": ["email", "domains", "provider", "options"]
+            "required": [
+              "email",
+              "domains",
+              "provider",
+              "options"
+            ]
           }
         },
         {
@@ -70,7 +81,9 @@
           "then": {
             "properties": {
               "options": {
-                "required": ["auth_token"],
+                "required": [
+                  "auth_token"
+                ],
                 "additionalProperties": false,
                 "properties": {
                   "auth_token": {
@@ -93,7 +106,11 @@
           "then": {
             "properties": {
               "options": {
-                "required": ["client_id", "email", "password"],
+                "required": [
+                  "client_id",
+                  "email",
+                  "password"
+                ],
                 "additionalProperties": false,
                 "properties": {
                   "client_id": {
@@ -124,7 +141,9 @@
           "then": {
             "properties": {
               "options": {
-                "required": ["token"],
+                "required": [
+                  "token"
+                ],
                 "additionalProperties": false,
                 "properties": {
                   "token": {
@@ -147,14 +166,21 @@
           "then": {
             "properties": {
               "options": {
-                "required": ["application_secret", "consumer_key"],
+                "required": [
+                  "application_secret",
+                  "consumer_key"
+                ],
                 "additionalProperties": false,
                 "oneOf": [
                   {
-                    "required": ["application_key"]
+                    "required": [
+                      "application_key"
+                    ]
                   },
                   {
-                    "required": ["oauth2_config"]
+                    "required": [
+                      "oauth2_config"
+                    ]
                   }
                 ],
                 "properties": {
@@ -205,7 +231,10 @@
                         "type": "string"
                       }
                     },
-                    "required": ["client_id", "client_secret"]
+                    "required": [
+                      "client_id",
+                      "client_secret"
+                    ]
                   }
                 }
               }
@@ -268,6 +297,14 @@
         }
       }
     },
+    "match_domains": {
+      "title": "Domains to match",
+      "type": "array",
+      "items": {
+        "type": "string"
+      },
+      "minItems": 1
+    },
     "timeout_shutdown": {
       "title": "Shutdown timeout (in seconds)",
       "type": "integer",
@@ -279,5 +316,7 @@
     }
   },
   "additionalProperties": false,
-  "required": ["providers"]
+  "required": [
+    "providers"
+  ]
 }

src/autocert/provider.go

@@ -5,6 +5,7 @@ import (
 	"crypto/tls"
 	"crypto/x509"
 	"os"
+	"path"
 	"reflect"
 	"sort"
 	"time"
@@ -59,8 +60,7 @@ func (p *Provider) ObtainCert() (res E.NestedError) {
 	defer b.To(&res)
 
 	if p.cfg.Provider == ProviderLocal {
-		b.Addf("provider is set to %q", ProviderLocal).WithSeverity(E.SeverityWarning)
+		return nil
-		return
 	}
 
 	if p.client == nil {
@@ -191,7 +191,19 @@ func (p *Provider) registerACME() E.NestedError {
 }
 
 func (p *Provider) saveCert(cert *certificate.Resource) E.NestedError {
-	err := os.WriteFile(p.cfg.KeyPath, cert.PrivateKey, 0o600) // -rw-------
+	//* This should have been done in setup
+	//* but double check is always a good choice
+	_, err := os.Stat(path.Dir(p.cfg.CertPath))
+	if err != nil {
+		if os.IsNotExist(err) {
+			if err = os.MkdirAll(path.Dir(p.cfg.CertPath), 0o755); err != nil {
+				return E.FailWith("create cert directory", err)
+			}
+		} else {
+			return E.FailWith("stat cert directory", err)
+		}
+	}
+	err = os.WriteFile(p.cfg.KeyPath, cert.PrivateKey, 0o600) // -rw-------
 	if err != nil {
 		return E.FailWith("write key file", err)
 	}
@@ -227,6 +239,10 @@ func (p *Provider) certState() CertState {
 }
 
 func (p *Provider) renewIfNeeded() E.NestedError {
+	if p.cfg.Provider == ProviderLocal {
+		return nil
+	}
+
 	switch p.certState() {
 	case CertStateExpired:
 		logger.Info("certs expired, renewing")

src/autocert/setup.go

@@ -14,7 +14,7 @@ func (p *Provider) Setup(ctx context.Context) (err E.NestedError) {
 		}
 		logger.Debug("obtaining cert due to error loading cert")
 		if err = p.ObtainCert(); err != nil {
-			return err.Warn()
+			return err
 		}
 	}
 

src/common/http.go

@@ -0,0 +1,25 @@
+package common
+
+import (
+	"crypto/tls"
+	"net"
+	"net/http"
+	"time"
+)
+
+var (
+	defaultDialer = net.Dialer{
+		Timeout:   60 * time.Second,
+		KeepAlive: 60 * time.Second,
+	}
+	DefaultTransport = &http.Transport{
+		Proxy:               http.ProxyFromEnvironment,
+		DialContext:         defaultDialer.DialContext,
+		MaxIdleConnsPerHost: 1000,
+	}
+	DefaultTransportNoTLS = func() *http.Transport {
+		var clone = DefaultTransport.Clone()
+		clone.TLSClientConfig = &tls.Config{InsecureSkipVerify: true}
+		return clone
+	}()
+)

src/config/config.go

@@ -31,25 +31,48 @@ type Config struct {
 	reloadReq     chan struct{}
 }
 
-func Load() (*Config, E.NestedError) {
+var instance *Config
-	cfg := &Config{
+
+func GetConfig() *Config {
+	return instance
+}
+
+func Load() E.NestedError {
+	if instance != nil {
+		return nil
+	}
+	instance = &Config{
+		value:          M.DefaultConfig(),
 		proxyProviders: F.NewMapOf[string, *PR.Provider](),
 		l:              logrus.WithField("module", "config"),
 		watcher:        W.NewFileWatcher(common.ConfigFileName),
 		reloadReq:      make(chan struct{}, 1),
 	}
-	return cfg, cfg.load()
+	return instance.load()
 }
 
 func Validate(data []byte) E.NestedError {
 	return U.ValidateYaml(U.GetSchema(common.ConfigSchemaPath), data)
 }
 
+func MatchDomains() []string {
+	if instance == nil {
+		logrus.Panic("config has not been loaded, please check if there is any errors")
+	}
+	return instance.value.MatchDomains
+}
+
 func (cfg *Config) Value() M.Config {
+	if cfg == nil {
+		logrus.Panic("config has not been loaded, please check if there is any errors")
+	}
 	return *cfg.value
 }
 
 func (cfg *Config) GetAutoCertProvider() *autocert.Provider {
+	if instance == nil {
+		logrus.Panic("config has not been loaded, please check if there is any errors")
+	}
 	return cfg.autocertProvider
 }
 
@@ -61,13 +84,11 @@ func (cfg *Config) Dispose() {
 	cfg.stopProviders()
 }
 
-func (cfg *Config) Reload() E.NestedError {
+func (cfg *Config) Reload() (err E.NestedError) {
 	cfg.stopProviders()
-	if err := cfg.load(); err.HasError() {
+	err = cfg.load()
-		return err
-	}
 	cfg.StartProxyProviders()
-	return nil
+	return
 }
 
 func (cfg *Config) StartProxyProviders() {
@@ -126,28 +147,28 @@ func (cfg *Config) load() (res E.NestedError) {
 	data, err := E.Check(os.ReadFile(common.ConfigPath))
 	if err.HasError() {
 		b.Add(E.FailWith("read config", err))
-		return
+		logrus.Fatal(b.Build())
 	}
 
 	if !common.NoSchemaValidation {
 		if err = Validate(data); err.HasError() {
 			b.Add(E.FailWith("schema validation", err))
-			return
+			logrus.Fatal(b.Build())
 		}
 	}
 
 	model := M.DefaultConfig()
 	if err := E.From(yaml.Unmarshal(data, model)); err.HasError() {
 		b.Add(E.FailWith("parse config", err))
-		return
+		logrus.Fatal(b.Build())
 	}
 
 	// errors are non fatal below
-	b.WithSeverity(E.SeverityWarning)
 	b.Add(cfg.initAutoCert(&model.AutoCert))
 	b.Add(cfg.loadProviders(&model.Providers))
 
 	cfg.value = model
+	R.SetFindMuxDomains(model.MatchDomains)
 	return
 }
 

src/docker/label.go

@@ -1,17 +1,37 @@
 package docker
 
 import (
+	"reflect"
 	"strings"
 
 	E "github.com/yusing/go-proxy/error"
 	U "github.com/yusing/go-proxy/utils"
+	F "github.com/yusing/go-proxy/utils/functional"
 )
 
-type Label struct {
+/*
-	Namespace string
+Formats:
-	Target    string
+  - namespace.attribute
-	Attribute string
+  - namespace.target.attribute
-	Value     any
+  - namespace.target.attribute.namespace2.attribute
+*/
+type (
+	Label struct {
+		Namespace string
+		Target    string
+		Attribute string
+		Value     any
+	}
+	NestedLabelMap map[string]U.SerializedObject
+	ValueParser    func(string) (any, E.NestedError)
+	ValueParserMap map[string]ValueParser
+)
+
+func (l *Label) String() string {
+	if l.Attribute == "" {
+		return l.Namespace + "." + l.Target
+	}
+	return l.Namespace + "." + l.Target + "." + l.Attribute
 }
 
 // Apply applies the value of a Label to the corresponding field in the given object.
@@ -23,12 +43,40 @@ type Label struct {
 // Returns:
 //   - error: an error if the field does not exist.
 func ApplyLabel[T any](obj *T, l *Label) E.NestedError {
-	return U.Deserialize(map[string]any{l.Attribute: l.Value}, obj)
+	if obj == nil {
+		return E.Invalid("nil object", l)
+	}
+	switch nestedLabel := l.Value.(type) {
+	case *Label:
+		var field reflect.Value
+		objType := reflect.TypeFor[T]()
+		for i := 0; i < reflect.TypeFor[T]().NumField(); i++ {
+			if objType.Field(i).Tag.Get("yaml") == l.Attribute {
+				field = reflect.ValueOf(obj).Elem().Field(i)
+				break
+			}
+		}
+		if !field.IsValid() {
+			return E.NotExist("field", l.Attribute)
+		}
+		dst, ok := field.Interface().(NestedLabelMap)
+		if !ok {
+			return E.Invalid("type", field.Type())
+		}
+		if dst == nil {
+			field.Set(reflect.MakeMap(reflect.TypeFor[NestedLabelMap]()))
+			dst = field.Interface().(NestedLabelMap)
+		}
+		if dst[nestedLabel.Namespace] == nil {
+			dst[nestedLabel.Namespace] = make(U.SerializedObject)
+		}
+		dst[nestedLabel.Namespace][nestedLabel.Attribute] = nestedLabel.Value
+		return nil
+	default:
+		return U.Deserialize(U.SerializedObject{l.Attribute: l.Value}, obj)
+	}
 }
 
-type ValueParser func(string) (any, E.NestedError)
-type ValueParserMap map[string]ValueParser
-
 func ParseLabel(label string, value string) (*Label, E.NestedError) {
 	parts := strings.Split(label, ".")
 
@@ -45,14 +93,22 @@ func ParseLabel(label string, value string) (*Label, E.NestedError) {
 		Value:     value,
 	}
 
-	if len(parts) == 3 {
+	switch len(parts) {
-		l.Attribute = parts[2]
+	case 2:
-	} else {
 		l.Attribute = l.Target
+	case 3:
+		l.Attribute = parts[2]
+	default:
+		l.Attribute = parts[2]
+		nestedLabel, err := ParseLabel(strings.Join(parts[3:], "."), value)
+		if err.HasError() {
+			return nil, err
+		}
+		l.Value = nestedLabel
 	}
 
 	// find if namespace has value parser
-	pm, ok := labelValueParserMap[l.Namespace]
+	pm, ok := valueParserMap.Load(l.Namespace)
 	if !ok {
 		return l, nil
 	}
@@ -64,15 +120,28 @@ func ParseLabel(label string, value string) (*Label, E.NestedError) {
 	// try to parse value
 	v, err := p(value)
 	if err.HasError() {
-		return nil, err
+		return nil, err.Subject(label)
 	}
 	l.Value = v
 	return l, nil
 }
 
 func RegisterNamespace(namespace string, pm ValueParserMap) {
-	labelValueParserMap[namespace] = pm
+	valueParserMap.Store(namespace, pm)
+}
+
+func GetRegisteredNamespaces() map[string][]string {
+	r := make(map[string][]string)
+
+	valueParserMap.RangeAll(func(ns string, vpm ValueParserMap) {
+		r[ns] = make([]string, 0, len(vpm))
+		for attr := range vpm {
+			r[ns] = append(r[ns], attr)
+		}
+	})
+
+	return r
 }
 
 // namespace:target.attribute -> func(string) (any, error)
-var labelValueParserMap = make(map[string]ValueParserMap)
+var valueParserMap = F.NewMapOf[string, ValueParserMap]()

src/docker/label_parser.go

@@ -7,7 +7,27 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
-func yamlListParser(value string) (any, E.NestedError) {
+const (
+	NSProxy                    = "proxy"
+	ProxyAttributePathPatterns = "path_patterns"
+	ProxyAttributeNoTLSVerify  = "no_tls_verify"
+	ProxyAttributeMiddlewares  = "middlewares"
+)
+
+var _ = func() int {
+	RegisterNamespace(NSProxy, ValueParserMap{
+		ProxyAttributePathPatterns: YamlStringListParser,
+		ProxyAttributeNoTLSVerify:  BoolParser,
+	})
+	return 0
+}()
+
+func YamlStringListParser(value string) (any, E.NestedError) {
+	/*
+		- foo
+		- bar
+		- baz
+	*/
 	value = strings.TrimSpace(value)
 	if value == "" {
 		return []string{}, nil
@@ -17,27 +37,36 @@ func yamlListParser(value string) (any, E.NestedError) {
 	return data, err
 }
 
-func yamlStringMappingParser(value string) (any, E.NestedError) {
+func YamlLikeMappingParser(allowDuplicate bool) func(string) (any, E.NestedError) {
-	value = strings.TrimSpace(value)
+	return func(value string) (any, E.NestedError) {
-	lines := strings.Split(value, "\n")
+		/*
-	h := make(map[string]string)
+			foo: bar
-	for _, line := range lines {
+			boo: baz
-		parts := strings.SplitN(line, ":", 2)
+		*/
-		if len(parts) != 2 {
+		value = strings.TrimSpace(value)
-			return nil, E.Invalid("set header statement", line)
+		lines := strings.Split(value, "\n")
-		}
+		h := make(map[string]string)
-		key := strings.TrimSpace(parts[0])
+		for _, line := range lines {
-		val := strings.TrimSpace(parts[1])
+			parts := strings.SplitN(line, ":", 2)
-		if existing, ok := h[key]; ok {
+			if len(parts) != 2 {
-			h[key] = existing + ", " + val
+				return nil, E.Invalid("syntax", line)
-		} else {
+			}
-			h[key] = val
+			key := strings.TrimSpace(parts[0])
+			val := strings.TrimSpace(parts[1])
+			if existing, ok := h[key]; ok {
+				if !allowDuplicate {
+					return nil, E.Duplicated("key", key)
+				}
+				h[key] = existing + ", " + val
+			} else {
+				h[key] = val
+			}
 		}
+		return h, nil
 	}
-	return h, nil
 }
 
-func boolParser(value string) (any, E.NestedError) {
+func BoolParser(value string) (any, E.NestedError) {
 	switch strings.ToLower(value) {
 	case "true", "yes", "1":
 		return true, nil
@@ -47,15 +76,3 @@ func boolParser(value string) (any, E.NestedError) {
 		return nil, E.Invalid("boolean value", value)
 	}
 }
-
-const NSProxy = "proxy"
-
-var _ = func() int {
-	RegisterNamespace(NSProxy, ValueParserMap{
-		"path_patterns": yamlListParser,
-		"set_headers":   yamlStringMappingParser,
-		"hide_headers":  yamlListParser,
-		"no_tls_verify": boolParser,
-	})
-	return 0
-}()

src/docker/label_parser_test.go

@@ -2,8 +2,6 @@ package docker
 
 import (
 	"fmt"
-	"reflect"
-	"strings"
 	"testing"
 
 	E "github.com/yusing/go-proxy/error"
@@ -14,21 +12,16 @@ func makeLabel(namespace string, alias string, field string) string {
 	return fmt.Sprintf("%s.%s.%s", namespace, alias, field)
 }
 
-func TestHomePageLabel(t *testing.T) {
+func TestParseLabel(t *testing.T) {
 	alias := "foo"
 	field := "ip"
 	v := "bar"
 	pl, err := ParseLabel(makeLabel(NSHomePage, alias, field), v)
 	ExpectNoError(t, err.Error())
-	if pl.Target != alias {
+	ExpectEqual(t, pl.Namespace, NSHomePage)
-		t.Errorf("Expected alias=%s, got %s", alias, pl.Target)
+	ExpectEqual(t, pl.Target, alias)
-	}
+	ExpectEqual(t, pl.Attribute, field)
-	if pl.Attribute != field {
+	ExpectEqual(t, pl.Value.(string), v)
-		t.Errorf("Expected field=%s, got %s", field, pl.Target)
-	}
-	if pl.Value != v {
-		t.Errorf("Expected value=%q, got %s", v, pl.Value)
-	}
 }
 
 func TestStringProxyLabel(t *testing.T) {
@@ -51,90 +44,63 @@ func TestBoolProxyLabelValid(t *testing.T) {
 	}
 
 	for k, v := range tests {
-		pl, err := ParseLabel(makeLabel(NSProxy, "foo", "no_tls_verify"), k)
+		pl, err := ParseLabel(makeLabel(NSProxy, "foo", ProxyAttributeNoTLSVerify), k)
 		ExpectNoError(t, err.Error())
 		ExpectEqual(t, pl.Value.(bool), v)
 	}
 }
 
 func TestBoolProxyLabelInvalid(t *testing.T) {
-	alias := "foo"
+	_, err := ParseLabel(makeLabel(NSProxy, "foo", ProxyAttributeNoTLSVerify), "invalid")
-	field := "no_tls_verify"
-	_, err := ParseLabel(makeLabel(NSProxy, alias, field), "invalid")
 	if !err.Is(E.ErrInvalid) {
 		t.Errorf("Expected err InvalidProxyLabel, got %s", err.Error())
 	}
 }
 
-func TestSetHeaderProxyLabelValid(t *testing.T) {
+// func TestSetHeaderProxyLabelValid(t *testing.T) {
-	v := `
+// 	v := `
-X-Custom-Header1: foo, bar
+// X-Custom-Header1: foo, bar
-X-Custom-Header1: baz
+// X-Custom-Header1: baz
-X-Custom-Header2: boo`
+// X-Custom-Header2: boo`
-	v = strings.TrimPrefix(v, "\n")
+// 	v = strings.TrimPrefix(v, "\n")
-	h := map[string]string{
+// 	h := map[string]string{
-		"X-Custom-Header1": "foo, bar, baz",
+// 		"X-Custom-Header1": "foo, bar, baz",
-		"X-Custom-Header2": "boo",
+// 		"X-Custom-Header2": "boo",
-	}
+// 	}
 
-	pl, err := ParseLabel(makeLabel(NSProxy, "foo", "set_headers"), v)
+// 	pl, err := ParseLabel(makeLabel(NSProxy, "foo", ProxyAttributeSetHeaders), v)
-	ExpectNoError(t, err.Error())
+// 	ExpectNoError(t, err.Error())
-	hGot := ExpectType[map[string]string](t, pl.Value)
+// 	hGot := ExpectType[map[string]string](t, pl.Value)
-	if hGot != nil && !reflect.DeepEqual(h, hGot) {
+// 	ExpectFalse(t, hGot == nil)
-		t.Errorf("Expected %v, got %v", h, hGot)
+// 	ExpectDeepEqual(t, h, hGot)
-	}
+// }
 
-}
+// func TestSetHeaderProxyLabelInvalid(t *testing.T) {
+// 	tests := []string{
+// 		"X-Custom-Header1 = bar",
+// 		"X-Custom-Header1",
+// 		"- X-Custom-Header1",
+// 	}
 
-func TestSetHeaderProxyLabelInvalid(t *testing.T) {
+// 	for _, v := range tests {
-	tests := []string{
+// 		_, err := ParseLabel(makeLabel(NSProxy, "foo", ProxyAttributeSetHeaders), v)
-		"X-Custom-Header1 = bar",
+// 		if !err.Is(E.ErrInvalid) {
-		"X-Custom-Header1",
+// 			t.Errorf("Expected invalid err for %q, got %s", v, err.Error())
-		"- X-Custom-Header1",
+// 		}
-	}
-
-	for _, v := range tests {
-		_, err := ParseLabel(makeLabel(NSProxy, "foo", "set_headers"), v)
-		if !err.Is(E.ErrInvalid) {
-			t.Errorf("Expected invalid err for %q, got %s", v, err.Error())
-		}
-	}
-}
-
-func TestHideHeadersProxyLabel(t *testing.T) {
-	v := `
-- X-Custom-Header1
-- X-Custom-Header2
-- X-Custom-Header3
-`
-	v = strings.TrimPrefix(v, "\n")
-	pl, err := ParseLabel(makeLabel(NSProxy, "foo", "hide_headers"), v)
-	ExpectNoError(t, err.Error())
-	sGot := ExpectType[[]string](t, pl.Value)
-	sWant := []string{"X-Custom-Header1", "X-Custom-Header2", "X-Custom-Header3"}
-	if sGot != nil {
-		ExpectDeepEqual(t, sGot, sWant)
-	}
-}
-
-// func TestCommaSepProxyLabelSingle(t *testing.T) {
-// 	v := "a"
-// 	pl, err := ParseLabel("proxy.aliases", v)
-// 	ExpectNoError(t, err)
-// 	sGot := ExpectType[[]string](t, pl.Value)
-// 	sWant := []string{"a"}
-// 	if sGot != nil {
-// 		ExpectEqual(t, sGot, sWant)
 // 	}
 // }
 
-// func TestCommaSepProxyLabelMulti(t *testing.T) {
+// func TestHideHeadersProxyLabel(t *testing.T) {
-// 	v := "X-Custom-Header1, X-Custom-Header2,X-Custom-Header3"
+// 	v := `
-// 	pl, err := ParseLabel("proxy.aliases", v)
+// - X-Custom-Header1
-// 	ExpectNoError(t, err)
+// - X-Custom-Header2
+// - X-Custom-Header3
+// `
+// 	v = strings.TrimPrefix(v, "\n")
+// 	pl, err := ParseLabel(makeLabel(NSProxy, "foo", ProxyAttributeHideHeaders), v)
+// 	ExpectNoError(t, err.Error())
 // 	sGot := ExpectType[[]string](t, pl.Value)
 // 	sWant := []string{"X-Custom-Header1", "X-Custom-Header2", "X-Custom-Header3"}
-// 	if sGot != nil {
+// 	ExpectFalse(t, sGot == nil)
-// 		ExpectEqual(t, sGot, sWant)
+// 	ExpectDeepEqual(t, sGot, sWant)
-// 	}
 // }

src/docker/label_test.go

@@ -0,0 +1,85 @@
+package docker
+
+import (
+	"fmt"
+	"testing"
+
+	U "github.com/yusing/go-proxy/utils"
+	. "github.com/yusing/go-proxy/utils/testing"
+)
+
+func TestNestedLabel(t *testing.T) {
+	mName := "middleware1"
+	mAttr := "prop1"
+	v := "value1"
+	pl, err := ParseLabel(makeLabel(NSProxy, "foo", fmt.Sprintf("%s.%s.%s", ProxyAttributeMiddlewares, mName, mAttr)), v)
+	ExpectNoError(t, err.Error())
+	sGot := ExpectType[*Label](t, pl.Value)
+	ExpectFalse(t, sGot == nil)
+	ExpectEqual(t, sGot.Namespace, mName)
+	ExpectEqual(t, sGot.Attribute, mAttr)
+}
+
+func TestApplyNestedLabel(t *testing.T) {
+	entry := new(struct {
+		Middlewares NestedLabelMap `yaml:"middlewares"`
+	})
+	mName := "middleware1"
+	mAttr := "prop1"
+	v := "value1"
+	pl, err := ParseLabel(makeLabel(NSProxy, "foo", fmt.Sprintf("%s.%s.%s", ProxyAttributeMiddlewares, mName, mAttr)), v)
+	ExpectNoError(t, err.Error())
+	err = ApplyLabel(entry, pl)
+	ExpectNoError(t, err.Error())
+	middleware1, ok := entry.Middlewares[mName]
+	ExpectTrue(t, ok)
+	got := ExpectType[string](t, middleware1[mAttr])
+	ExpectEqual(t, got, v)
+}
+
+func TestApplyNestedLabelExisting(t *testing.T) {
+	mName := "middleware1"
+	mAttr := "prop1"
+	v := "value1"
+
+	checkAttr := "prop2"
+	checkV := "value2"
+	entry := new(struct {
+		Middlewares NestedLabelMap `yaml:"middlewares"`
+	})
+	entry.Middlewares = make(NestedLabelMap)
+	entry.Middlewares[mName] = make(U.SerializedObject)
+	entry.Middlewares[mName][checkAttr] = checkV
+
+	pl, err := ParseLabel(makeLabel(NSProxy, "foo", fmt.Sprintf("%s.%s.%s", ProxyAttributeMiddlewares, mName, mAttr)), v)
+	ExpectNoError(t, err.Error())
+	err = ApplyLabel(entry, pl)
+	ExpectNoError(t, err.Error())
+	middleware1, ok := entry.Middlewares[mName]
+	ExpectTrue(t, ok)
+	got := ExpectType[string](t, middleware1[mAttr])
+	ExpectEqual(t, got, v)
+
+	// check if prop2 is affected
+	ExpectFalse(t, middleware1[checkAttr] == nil)
+	got = ExpectType[string](t, middleware1[checkAttr])
+	ExpectEqual(t, got, checkV)
+}
+
+func TestApplyNestedLabelNoAttr(t *testing.T) {
+	mName := "middleware1"
+	v := "value1"
+
+	entry := new(struct {
+		Middlewares NestedLabelMap `yaml:"middlewares"`
+	})
+	entry.Middlewares = make(NestedLabelMap)
+	entry.Middlewares[mName] = make(U.SerializedObject)
+
+	pl, err := ParseLabel(makeLabel(NSProxy, "foo", fmt.Sprintf("%s.%s", ProxyAttributeMiddlewares, mName)), v)
+	ExpectNoError(t, err.Error())
+	err = ApplyLabel(entry, pl)
+	ExpectNoError(t, err.Error())
+	_, ok := entry.Middlewares[mName]
+	ExpectTrue(t, ok)
+}

src/error/builder.go

@@ -10,9 +10,8 @@ type Builder struct {
 }
 
 type builder struct {
-	message  string
+	message string
-	errors   []NestedError
+	errors  []NestedError
-	severity Severity
 	sync.Mutex
 }
 
@@ -40,11 +39,6 @@ func (b Builder) Addf(format string, args ...any) Builder {
 	return b.Add(errorf(format, args...))
 }
 
-func (b Builder) WithSeverity(s Severity) Builder {
-	b.severity = s
-	return b
-}
-
 // Build builds a NestedError based on the errors collected in the Builder.
 //
 // If there are no errors in the Builder, it returns a Nil() NestedError.
@@ -58,7 +52,7 @@ func (b Builder) Build() NestedError {
 	} else if len(b.errors) == 1 {
 		return b.errors[0]
 	}
-	return Join(b.message, b.errors...).Severity(b.severity)
+	return Join(b.message, b.errors...)
 }
 
 func (b Builder) To(ptr *NestedError) {

src/error/error.go

@@ -9,17 +9,10 @@ import (
 type (
 	NestedError = *nestedError
 	nestedError struct {
-		subject  string
+		subject string
-		err      error
+		err     error
-		extras   []nestedError
+		extras  []nestedError
-		severity Severity
 	}
-	Severity uint8
-)
-
-const (
-	SeverityWarning Severity = iota
-	SeverityFatal
 )
 
 func From(err error) NestedError {
@@ -164,22 +157,6 @@ func (ne NestedError) Subjectf(format string, args ...any) NestedError {
 	return ne
 }
 
-func (ne NestedError) Severity(s Severity) NestedError {
-	if ne == nil {
-		return ne
-	}
-	ne.severity = s
-	return ne
-}
-
-func (ne NestedError) Warn() NestedError {
-	if ne == nil {
-		return ne
-	}
-	ne.severity = SeverityWarning
-	return ne
-}
-
 func (ne NestedError) NoError() bool {
 	return ne == nil
 }
@@ -188,14 +165,6 @@ func (ne NestedError) HasError() bool {
 	return ne != nil
 }
 
-func (ne NestedError) IsFatal() bool {
-	return ne != nil && ne.severity == SeverityFatal
-}
-
-func (ne NestedError) IsWarning() bool {
-	return ne != nil && ne.severity == SeverityWarning
-}
-
 func errorf(format string, args ...any) NestedError {
 	return From(fmt.Errorf(format, args...))
 }

src/error/error_test.go

@@ -31,11 +31,11 @@ func TestErrorNestedIs(t *testing.T) {
 
 	err = Failure("some reason")
 	ExpectTrue(t, err.Is(ErrFailure))
-	ExpectFalse(t, err.Is(ErrAlreadyExist))
+	ExpectFalse(t, err.Is(ErrDuplicated))
 
-	err.With(AlreadyExist("something", ""))
+	err.With(Duplicated("something", ""))
 	ExpectTrue(t, err.Is(ErrFailure))
-	ExpectTrue(t, err.Is(ErrAlreadyExist))
+	ExpectTrue(t, err.Is(ErrDuplicated))
 	ExpectFalse(t, err.Is(ErrInvalid))
 }
 

src/error/errors.go

@@ -5,14 +5,14 @@ import (
 )
 
 var (
-	ErrFailure      = stderrors.New("failed")
+	ErrFailure     = stderrors.New("failed")
-	ErrInvalid      = stderrors.New("invalid")
+	ErrInvalid     = stderrors.New("invalid")
-	ErrUnsupported  = stderrors.New("unsupported")
+	ErrUnsupported = stderrors.New("unsupported")
-	ErrUnexpected   = stderrors.New("unexpected")
+	ErrUnexpected  = stderrors.New("unexpected")
-	ErrNotExists    = stderrors.New("does not exist")
+	ErrNotExists   = stderrors.New("does not exist")
-	ErrMissing      = stderrors.New("missing")
+	ErrMissing     = stderrors.New("missing")
-	ErrAlreadyExist = stderrors.New("already exist")
+	ErrDuplicated  = stderrors.New("duplicated")
-	ErrOutOfRange   = stderrors.New("out of range")
+	ErrOutOfRange  = stderrors.New("out of range")
 )
 
 const fmtSubjectWhat = "%w %v: %q"
@@ -53,8 +53,8 @@ func Missing(subject any) NestedError {
 	return errorf("%w %v", ErrMissing, subject)
 }
 
-func AlreadyExist(subject, what any) NestedError {
+func Duplicated(subject, what any) NestedError {
-	return errorf("%v %w: %v", subject, ErrAlreadyExist, what)
+	return errorf("%w %v: %v", ErrDuplicated, subject, what)
 }
 
 func OutOfRange(subject string, value any) NestedError {

src/go.mod

@@ -17,7 +17,7 @@ require (
 require (
 	github.com/Microsoft/go-winio v0.6.2 // indirect
 	github.com/cenkalti/backoff/v4 v4.3.0 // indirect
-	github.com/cloudflare/cloudflare-go v0.104.0 // indirect
+	github.com/cloudflare/cloudflare-go v0.105.0 // indirect
 	github.com/containerd/log v0.1.0 // indirect
 	github.com/distribution/reference v0.6.0 // indirect
 	github.com/docker/go-connections v0.5.0 // indirect

src/go.sum

@@ -4,8 +4,8 @@ github.com/Microsoft/go-winio v0.6.2 h1:F2VQgta7ecxGYO8k3ZZz3RS8fVIXVxONVUPlNERo
 github.com/Microsoft/go-winio v0.6.2/go.mod h1:yd8OoFMLzJbo9gZq8j5qaps8bJ9aShtEA8Ipt1oGCvU=
 github.com/cenkalti/backoff/v4 v4.3.0 h1:MyRJ/UdXutAwSAT+s3wNd7MfTIcy71VQueUuFK343L8=
 github.com/cenkalti/backoff/v4 v4.3.0/go.mod h1:Y3VNntkOUPxTVeUxJ/G5vcM//AlwfmyYozVcomhLiZE=
-github.com/cloudflare/cloudflare-go v0.104.0 h1:R/lB0dZupaZbOgibAH/BRrkFbZ6Acn/WsKg2iX2xXuY=
+github.com/cloudflare/cloudflare-go v0.105.0 h1:yu2IatITLZ4dw7/byzRrlE5DfUvtub0k9CHZ5zBlj90=
-github.com/cloudflare/cloudflare-go v0.104.0/go.mod h1:pfUQ4PIG4ISI0/Mmc21Bp86UnFU0ktmPf3iTgbSL+cM=
+github.com/cloudflare/cloudflare-go v0.105.0/go.mod h1:pfUQ4PIG4ISI0/Mmc21Bp86UnFU0ktmPf3iTgbSL+cM=
 github.com/containerd/log v0.1.0 h1:TCJt7ioM2cr/tfR8GPbGf9/VRAX8D2B4PjzCpfX540I=
 github.com/containerd/log v0.1.0/go.mod h1:VRRf09a7mHDIRezVKTRCrOq78v577GXq3bSa3EhrzVo=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=

src/http/modify_response_writer.go

@@ -0,0 +1,96 @@
+// Modified from Traefik Labs's MIT-licensed code (https://github.com/traefik/traefik/blob/master/pkg/middlewares/response_modifier.go)
+// Copyright (c) 2020-2024 Traefik Labs
+
+package http
+
+import (
+	"bufio"
+	"fmt"
+	"net"
+	"net/http"
+)
+
+type ModifyResponseFunc func(*http.Response) error
+type ModifyResponseWriter struct {
+	w http.ResponseWriter
+	r *http.Request
+
+	headerSent bool
+	code       int
+
+	modifier    ModifyResponseFunc
+	modified    bool
+	modifierErr error
+}
+
+func NewModifyResponseWriter(w http.ResponseWriter, r *http.Request, f ModifyResponseFunc) *ModifyResponseWriter {
+	return &ModifyResponseWriter{
+		w:        w,
+		r:        r,
+		modifier: f,
+		code:     http.StatusOK,
+	}
+}
+
+func (w *ModifyResponseWriter) WriteHeader(code int) {
+	if w.headerSent {
+		return
+	}
+
+	if code >= http.StatusContinue && code < http.StatusOK {
+		w.w.WriteHeader(code)
+	}
+
+	defer func() {
+		w.headerSent = true
+		w.code = code
+	}()
+
+	if w.modifier == nil || w.modified {
+		w.w.WriteHeader(code)
+		return
+	}
+
+	resp := http.Response{
+		Header:  w.w.Header(),
+		Request: w.r,
+	}
+
+	if err := w.modifier(&resp); err != nil {
+		w.modifierErr = err
+		logger.Errorf("error modifying response: %s", err)
+		w.w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	w.modified = true
+	w.w.WriteHeader(code)
+}
+
+func (w *ModifyResponseWriter) Header() http.Header {
+	return w.w.Header()
+}
+
+func (w *ModifyResponseWriter) Write(b []byte) (int, error) {
+	w.WriteHeader(w.code)
+	if w.modifierErr != nil {
+		return 0, w.modifierErr
+	}
+	return w.w.Write(b)
+}
+
+// Hijack hijacks the connection.
+func (w *ModifyResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	if h, ok := w.w.(http.Hijacker); ok {
+		return h.Hijack()
+	}
+
+	return nil, nil, fmt.Errorf("not a hijacker: %T", w.w)
+}
+
+// Flush sends any buffered data to the client.
+func (w *ModifyResponseWriter) Flush() {
+	if flusher, ok := w.w.(http.Flusher); ok {
+		flusher.Flush()
+	}
+}

src/http/reverse_proxy_mod.go

@@ -1,7 +1,13 @@
-package proxy
+// Copyright 2011 The Go Authors.
+// Modified from the Go project under the a BSD-style License (https://cs.opensource.google/go/go/+/refs/tags/go1.23.1:src/net/http/httputil/reverseproxy.go)
+// https://cs.opensource.google/go/go/+/master:LICENSE
 
-// A small mod on net/http/httputil/reverseproxy.go
+package http
-// that doubled the performance
+
+// This is a small mod on net/http/httputil/reverseproxy.go
+// that boosts performance in some cases
+// and compatible to other modules of this project
+// Copyright (c) 2024 yusing
 
 import (
 	"context"
@@ -52,6 +58,21 @@ type ProxyRequest struct {
 //		r.SetXForwarded()
 //	}
 func (r *ProxyRequest) SetXForwarded() {
+	clientIP, _, err := net.SplitHostPort(r.In.RemoteAddr)
+	if err == nil {
+		r.Out.Header.Set("X-Forwarded-For", clientIP)
+	} else {
+		r.Out.Header.Del("X-Forwarded-For")
+	}
+	r.Out.Header.Set("X-Forwarded-Host", r.In.Host)
+	if r.In.TLS == nil {
+		r.Out.Header.Set("X-Forwarded-Proto", "http")
+	} else {
+		r.Out.Header.Set("X-Forwarded-Proto", "https")
+	}
+}
+
+func (r *ProxyRequest) AddXForwarded() {
 	clientIP, _, err := net.SplitHostPort(r.In.RemoteAddr)
 	if err == nil {
 		prior := r.Out.Header["X-Forwarded-For"]
@@ -104,28 +125,6 @@ type ReverseProxy struct {
 	// If nil, http.DefaultTransport is used.
 	Transport http.RoundTripper
 
-	// FlushInterval specifies the flush interval
-	// to flush to the client while copying the
-	// response body.
-	// If zero, no periodic flushing is done.
-	// A negative value means to flush immediately
-	// after each write to the client.
-	// The FlushInterval is ignored when ReverseProxy
-	// recognizes a response as a streaming response, or
-	// if its ContentLength is -1; for such responses, writes
-	// are flushed to the client immediately.
-	// FlushInterval time.Duration
-
-	// ErrorLog specifies an optional logger for errors
-	// that occur when attempting to proxy the request.
-	// If nil, logging is done via the log package's standard logger.
-	// ErrorLog *log.Logger
-
-	// BufferPool optionally specifies a buffer pool to
-	// get byte slices for use by io.CopyBuffer when
-	// copying HTTP response bodies.
-	// BufferPool BufferPool
-
 	// ModifyResponse is an optional function that modifies the
 	// Response from the backend. It is called if the backend
 	// returns a response at all, with any HTTP status code.
@@ -208,36 +207,11 @@ func joinURLPath(a, b *url.URL) (path, rawpath string) {
 //		},
 //	}
 //
-// TODO: headers in ModifyResponse
+
-func NewReverseProxy(target *url.URL, transport http.RoundTripper, entry *ReverseProxyEntry) *ReverseProxy {
+func NewReverseProxy(target *url.URL, transport http.RoundTripper) *ReverseProxy {
-	// check on init rather than on request
-	var setHeaders = func(r *http.Request) {}
-	var hideHeaders = func(r *http.Request) {}
-	if len(entry.SetHeaders) > 0 {
-		setHeaders = func(r *http.Request) {
-			h := entry.SetHeaders.Clone()
-			for k, vv := range h {
-				if k == "Host" {
-					r.Host = vv[0]
-				} else {
-					r.Header[k] = vv
-				}
-			}
-		}
-	}
-	if len(entry.HideHeaders) > 0 {
-		hideHeaders = func(r *http.Request) {
-			for _, k := range entry.HideHeaders {
-				r.Header.Del(k)
-			}
-		}
-	}
 	rp := &ReverseProxy{
 		Rewrite: func(pr *ProxyRequest) {
 			rewriteRequestURL(pr.Out, target)
-			// pr.SetXForwarded()
-			setHeaders(pr.Out)
-			hideHeaders(pr.Out)
 		}, Transport: transport,
 	}
 	rp.ServeHTTP = rp.serveHTTP
@@ -256,6 +230,23 @@ func rewriteRequestURL(req *http.Request, target *url.URL) {
 	}
 }
 
+// Hop-by-hop headers. These are removed when sent to the backend.
+// As of RFC 7230, hop-by-hop headers are required to appear in the
+// Connection header field. These are the headers defined by the
+// obsoleted RFC 2616 (section 13.5.1) and are used for backward
+// compatibility.
+var hopHeaders = []string{
+	"Connection",
+	"Proxy-Connection", // non-standard but still sent by libcurl and rejected by e.g. google
+	"Keep-Alive",
+	"Proxy-Authenticate",
+	"Proxy-Authorization",
+	"Te",      // canonicalized version of "TE"
+	"Trailer", // not Trailers per URL above; https://www.rfc-editor.org/errata_search.php?eid=4522
+	"Transfer-Encoding",
+	"Upgrade",
+}
+
 func copyHeader(dst, src http.Header) {
 	for k, vv := range src {
 		for _, v := range vv {
@@ -331,12 +322,14 @@ func (p *ReverseProxy) serveHTTP(rw http.ResponseWriter, req *http.Request) {
 
 	outreq.Close = false
 
-	reqUpType := upgradeType(outreq.Header)
+	reqUpType := UpgradeType(outreq.Header)
 	if !IsPrint(reqUpType) {
 		p.errorHandler(rw, req, fmt.Errorf("client tried to switch to invalid protocol %q", reqUpType))
 		return
 	}
 
+	RemoveHopByHopHeaders(outreq.Header)
+
 	// Issue 21096: tell backend applications that care about trailer support
 	// that we support trailers. (We do, but we don't go out of our way to
 	// advertise that unless the incoming client request thought it was worth
@@ -458,16 +451,34 @@ func (p *ReverseProxy) serveHTTP(rw http.ResponseWriter, req *http.Request) {
 	}
 }
 
-func upgradeType(h http.Header) string {
+func UpgradeType(h http.Header) string {
 	if !httpguts.HeaderValuesContainsToken(h["Connection"], "Upgrade") {
 		return ""
 	}
 	return h.Get("Upgrade")
 }
 
+// RemoveHopByHopHeaders removes hop-by-hop headers.
+func RemoveHopByHopHeaders(h http.Header) {
+	// RFC 7230, section 6.1: Remove headers listed in the "Connection" header.
+	for _, f := range h["Connection"] {
+		for _, sf := range strings.Split(f, ",") {
+			if sf = textproto.TrimString(sf); sf != "" {
+				h.Del(sf)
+			}
+		}
+	}
+	// RFC 2616, section 13.5.1: Remove a set of known hop-by-hop headers.
+	// This behavior is superseded by the RFC 7230 Connection header, but
+	// preserve it for backwards compatibility.
+	for _, f := range hopHeaders {
+		h.Del(f)
+	}
+}
+
 func (p *ReverseProxy) handleUpgradeResponse(rw http.ResponseWriter, req *http.Request, res *http.Response) {
-	reqUpType := upgradeType(req.Header)
+	reqUpType := UpgradeType(req.Header)
-	resUpType := upgradeType(res.Header)
+	resUpType := UpgradeType(res.Header)
 	if !IsPrint(resUpType) { // We know reqUpType is ASCII, it's checked by the caller.
 		p.errorHandler(rw, req, fmt.Errorf("backend tried to switch to invalid protocol %q", resUpType))
 	}

src/main.go

@@ -47,11 +47,10 @@ func main() {
 		logrus.SetOutput(io.Discard)
 	} else {
 		logrus.SetFormatter(&logrus.TextFormatter{
-			DisableSorting:         true,
+			DisableSorting:  true,
-			DisableLevelTruncation: true,
+			FullTimestamp:   true,
-			FullTimestamp:          true,
+			ForceColors:     true,
-			ForceColors:            true,
+			TimestampFormat: "01-02 15:04:05",
-			TimestampFormat:        "01-02 15:04:05",
 		})
 	}
 
@@ -76,10 +75,11 @@ func main() {
 		return
 	}
 
-	cfg, err := config.Load()
+	err := config.Load()
-	if err.IsFatal() {
+	if err != nil {
-		log.Fatal(err)
+		logrus.Warn(err)
 	}
+	cfg := config.GetConfig()
 
 	switch args.Command {
 	case common.CommandListConfigs:
@@ -96,6 +96,10 @@ func main() {
 		return
 	}
 
+	if common.IsDebug {
+		printJSON(docker.GetRegisteredNamespaces())
+	}
+
 	cfg.StartProxyProviders()
 
 	if err.HasError() {
@@ -116,10 +120,7 @@ func main() {
 
 	if autocert != nil {
 		ctx, cancel := context.WithCancel(context.Background())
-		if err = autocert.Setup(ctx); err != nil && err.IsWarning() {
+		if err = autocert.Setup(ctx); err != nil {
-			cancel()
-			l.Warn(err)
-		} else if err.IsFatal() {
 			l.Fatal(err)
 		} else {
 			onShutdown.Add(cancel)
@@ -192,7 +193,7 @@ func funcName(f func()) string {
 }
 
 func printJSON(obj any) {
-	j, err := E.Check(json.Marshal(obj))
+	j, err := E.Check(json.MarshalIndent(obj, "", "  "))
 	if err.HasError() {
 		logrus.Fatal(err)
 	}

src/models/config.go

@@ -3,6 +3,7 @@ package model
 type Config struct {
 	Providers       ProxyProviders `yaml:",flow" json:"providers"`
 	AutoCert        AutoCertConfig `yaml:",flow" json:"autocert"`
+	MatchDomains    []string       `yaml:"match_domains" json:"match_domains"`
 	TimeoutShutdown int            `yaml:"timeout_shutdown" json:"timeout_shutdown"`
 	RedirectToHTTPS bool           `yaml:"redirect_to_https" json:"redirect_to_https"`
 }
@@ -11,6 +12,6 @@ func DefaultConfig() *Config {
 	return &Config{
 		Providers:       ProxyProviders{},
 		TimeoutShutdown: 3,
-		RedirectToHTTPS: true,
+		RedirectToHTTPS: false,
 	}
 }

src/models/raw_entry.go

@@ -14,14 +14,13 @@ type (
 	RawEntry struct {
 		// raw entry object before validation
 		// loaded from docker labels or yaml file
-		Alias        string            `yaml:"-" json:"-"`
+		Alias        string           `yaml:"-" json:"-"`
-		Scheme       string            `yaml:"scheme" json:"scheme"`
+		Scheme       string           `yaml:"scheme" json:"scheme"`
-		Host         string            `yaml:"host" json:"host"`
+		Host         string           `yaml:"host" json:"host"`
-		Port         string            `yaml:"port" json:"port"`
+		Port         string           `yaml:"port" json:"port"`
-		NoTLSVerify  bool              `yaml:"no_tls_verify" json:"no_tls_verify"` // https proxy only
+		NoTLSVerify  bool             `yaml:"no_tls_verify" json:"no_tls_verify"` // https proxy only
-		PathPatterns []string          `yaml:"path_patterns" json:"path_patterns"` // http(s) proxy only
+		PathPatterns []string         `yaml:"path_patterns" json:"path_patterns"` // http(s) proxy only
-		SetHeaders   map[string]string `yaml:"set_headers" json:"set_headers"`     // http(s) proxy only
+		Middlewares  D.NestedLabelMap `yaml:"middlewares" json:"middlewares"`
-		HideHeaders  []string          `yaml:"hide_headers" json:"hide_headers"`   // http(s) proxy only
 
 		/* Docker only */
 		*D.ProxyProperties `yaml:"-" json:"proxy_properties"`
@@ -44,12 +43,16 @@ func (e *RawEntry) FillMissingFields() bool {
 		if pp == "" {
 			pp = strconv.Itoa(port)
 		}
-		e.Scheme = "tcp"
+		if e.Scheme == "" {
+			e.Scheme = "tcp"
+		}
 	} else if port, ok := ImageNamePortMap[e.ImageName]; ok {
 		if pp == "" {
 			pp = strconv.Itoa(port)
 		}
-		e.Scheme = "http"
+		if e.Scheme == "" {
+			e.Scheme = "http"
+		}
 	} else if pp == "" && e.Scheme == "https" {
 		pp = "443"
 	} else if pp == "" {

src/proxy/entry.go

@@ -2,10 +2,10 @@ package proxy
 
 import (
 	"fmt"
-	"net/http"
 	"net/url"
 	"time"
 
+	D "github.com/yusing/go-proxy/docker"
 	E "github.com/yusing/go-proxy/error"
 	M "github.com/yusing/go-proxy/models"
 	T "github.com/yusing/go-proxy/proxy/fields"
@@ -18,8 +18,7 @@ type (
 		URL          *url.URL
 		NoTLSVerify  bool
 		PathPatterns T.PathPatterns
-		SetHeaders   http.Header
+		Middlewares  D.NestedLabelMap
-		HideHeaders  []string
 
 		/* Docker only */
 		IdleTimeout      time.Duration
@@ -78,9 +77,6 @@ func validateRPEntry(m *M.RawEntry, s T.Scheme, b E.Builder) *ReverseProxyEntry
 	pathPatterns, err := T.ValidatePathPatterns(m.PathPatterns)
 	b.Add(err)
 
-	setHeaders, err := T.ValidateHTTPHeaders(m.SetHeaders)
-	b.Add(err)
-
 	url, err := E.Check(url.Parse(fmt.Sprintf("%s://%s:%d", s, host, port)))
 	b.Add(err)
 
@@ -111,8 +107,7 @@ func validateRPEntry(m *M.RawEntry, s T.Scheme, b E.Builder) *ReverseProxyEntry
 		URL:              url,
 		NoTLSVerify:      m.NoTLSVerify,
 		PathPatterns:     pathPatterns,
-		SetHeaders:       setHeaders,
+		Middlewares:      m.Middlewares,
-		HideHeaders:      m.HideHeaders,
 		IdleTimeout:      idleTimeout,
 		WakeTimeout:      wakeTimeout,
 		StopMethod:       stopMethod,

src/proxy/provider/docker.go

@@ -4,7 +4,9 @@ import (
 	"fmt"
 	"regexp"
 	"strconv"
+	"strings"
 
+	"github.com/sirupsen/logrus"
 	D "github.com/yusing/go-proxy/docker"
 	E "github.com/yusing/go-proxy/error"
 	M "github.com/yusing/go-proxy/models"
@@ -17,6 +19,7 @@ type DockerProvider struct {
 }
 
 var AliasRefRegex = regexp.MustCompile(`#\d+`)
+var AliasRefRegexOld = regexp.MustCompile(`\$\d+`)
 
 func DockerProviderImpl(dockerHost string) (ProviderImpl, E.NestedError) {
 	hostname, err := D.ParseDockerHostname(dockerHost)
@@ -152,6 +155,20 @@ func (p *DockerProvider) applyLabel(container D.Container, entries M.RawEntries,
 	b := E.NewBuilder("errors in label %s", key)
 	defer b.To(&res)
 
+	refErr := E.NewBuilder("errors parsing alias references")
+	replaceIndexRef := func(ref string) string {
+		index, err := strconv.Atoi(ref[1:])
+		if err != nil {
+			refErr.Add(E.Invalid("integer", ref))
+			return ref
+		}
+		if index < 1 || index > len(container.Aliases) {
+			refErr.Add(E.OutOfRange("index", ref))
+			return ref
+		}
+		return container.Aliases[index-1]
+	}
+
 	lbl, err := D.ParseLabel(key, val)
 	if err.HasError() {
 		b.Add(err.Subject(key))
@@ -163,22 +180,14 @@ func (p *DockerProvider) applyLabel(container D.Container, entries M.RawEntries,
 		// apply label for all aliases
 		entries.RangeAll(func(a string, e *M.RawEntry) {
 			if err = D.ApplyLabel(e, lbl); err.HasError() {
-				b.Add(err.Subject(lbl.Target))
+				b.Add(err.Subjectf("alias %s", lbl.Target))
 			}
 		})
 	} else {
-		refErr := E.NewBuilder("errors parsing alias references")
+		lbl.Target = AliasRefRegex.ReplaceAllStringFunc(lbl.Target, replaceIndexRef)
-		lbl.Target = AliasRefRegex.ReplaceAllStringFunc(lbl.Target, func(ref string) string {
+		lbl.Target = AliasRefRegexOld.ReplaceAllStringFunc(lbl.Target, func(s string) string {
-			index, err := strconv.Atoi(ref[1:])
+			logrus.Warnf("%q should now be %q, old syntax will be removed in a future version", lbl, strings.ReplaceAll(lbl.String(), "$", "#"))
-			if err != nil {
+			return replaceIndexRef(s)
-				refErr.Add(E.Invalid("integer", ref))
-				return ref
-			}
-			if index < 1 || index > len(container.Aliases) {
-				refErr.Add(E.OutOfRange("index", ref))
-				return ref
-			}
-			return container.Aliases[index-1]
 		})
 		if refErr.HasError() {
 			b.Add(refErr.Build())
@@ -190,7 +199,7 @@ func (p *DockerProvider) applyLabel(container D.Container, entries M.RawEntries,
 			return
 		}
 		if err = D.ApplyLabel(config, lbl); err.HasError() {
-			b.Add(err.Subject(lbl.Target))
+			b.Add(err.Subjectf("alias %s", lbl.Target))
 		}
 	}
 	return

src/proxy/provider/docker_test.go

@@ -132,7 +132,8 @@ func TestApplyLabel(t *testing.T) {
 	ExpectEqual(t, b.Scheme, "http")
 	ExpectEqual(t, b.Port, "1234")
 	ExpectEqual(t, c.Scheme, "https")
-	ExpectEqual(t, c.Port, "1111")
+	// map does not necessary follow the order above
+	ExpectEqualAny(t, c.Port, []string{"1111", "1234"})
 }
 
 func TestApplyLabelWithRef(t *testing.T) {
@@ -142,9 +143,9 @@ func TestApplyLabelWithRef(t *testing.T) {
 		Labels: map[string]string{
 			D.LabelAliases:    "a,b,c",
 			"proxy.#1.host":   "localhost",
-			"proxy.*.port":    "1111",
 			"proxy.#1.port":   "4444",
 			"proxy.#2.port":   "9999",
+			"proxy.#3.port":   "1111",
 			"proxy.#3.scheme": "https",
 		},
 		Ports: []types.Port{

src/route/http.go

@@ -1,20 +1,20 @@
 package route
 
 import (
-	"crypto/tls"
-	"net"
 	"sync"
-	"time"
 
 	"net/http"
 	"net/url"
 	"strings"
 
 	"github.com/sirupsen/logrus"
+	"github.com/yusing/go-proxy/common"
 	"github.com/yusing/go-proxy/docker/idlewatcher"
 	E "github.com/yusing/go-proxy/error"
+	. "github.com/yusing/go-proxy/http"
 	P "github.com/yusing/go-proxy/proxy"
 	PT "github.com/yusing/go-proxy/proxy/fields"
+	"github.com/yusing/go-proxy/route/middleware"
 	F "github.com/yusing/go-proxy/utils/functional"
 )
 
@@ -26,7 +26,7 @@ type (
 
 		entry   *P.ReverseProxyEntry
 		mux     *http.ServeMux
-		handler *P.ReverseProxy
+		handler *ReverseProxy
 
 		regIdleWatcher   func() E.NestedError
 		unregIdleWatcher func()
@@ -36,18 +36,41 @@ type (
 	SubdomainKey = PT.Alias
 )
 
+var (
+	findMuxFunc = findMuxAnyDomain
+
+	httpRoutes   = F.NewMapOf[SubdomainKey, *HTTPRoute]()
+	httpRoutesMu sync.Mutex
+	globalMux    = http.NewServeMux() // TODO: support regex subdomain matching
+)
+
+func SetFindMuxDomains(domains []string) {
+	if len(domains) == 0 {
+		findMuxFunc = findMuxAnyDomain
+	} else {
+		findMuxFunc = findMuxByDomain(domains)
+	}
+}
+
 func NewHTTPRoute(entry *P.ReverseProxyEntry) (*HTTPRoute, E.NestedError) {
 	var trans *http.Transport
 	var regIdleWatcher func() E.NestedError
 	var unregIdleWatcher func()
 
 	if entry.NoTLSVerify {
-		trans = transportNoTLS.Clone()
+		trans = common.DefaultTransportNoTLS.Clone()
 	} else {
-		trans = transport.Clone()
+		trans = common.DefaultTransport.Clone()
 	}
 
-	rp := P.NewReverseProxy(entry.URL, trans, entry)
+	rp := NewReverseProxy(entry.URL, trans)
+
+	if len(entry.Middlewares) > 0 {
+		err := middleware.PatchReverseProxy(rp, entry.Middlewares)
+		if err != nil {
+			return nil, err
+		}
+	}
 
 	if entry.UseIdleWatcher() {
 		// allow time for response header up to `WakeTimeout`
@@ -74,7 +97,7 @@ func NewHTTPRoute(entry *P.ReverseProxyEntry) (*HTTPRoute, E.NestedError) {
 
 	_, exists := httpRoutes.Load(entry.Alias)
 	if exists {
-		return nil, E.AlreadyExist("HTTPRoute alias", entry.Alias)
+		return nil, E.Duplicated("HTTPRoute alias", entry.Alias)
 	}
 
 	r := &HTTPRoute{
@@ -94,11 +117,16 @@ func (r *HTTPRoute) String() string {
 }
 
 func (r *HTTPRoute) Start() E.NestedError {
+	if r.mux != nil {
+		return nil
+	}
+
 	httpRoutesMu.Lock()
 	defer httpRoutesMu.Unlock()
 
 	if r.regIdleWatcher != nil {
 		if err := r.regIdleWatcher(); err.HasError() {
+			r.unregIdleWatcher = nil
 			return err
 		}
 	}
@@ -113,6 +141,10 @@ func (r *HTTPRoute) Start() E.NestedError {
 }
 
 func (r *HTTPRoute) Stop() E.NestedError {
+	if r.mux == nil {
+		return nil
+	}
+
 	httpRoutesMu.Lock()
 	defer httpRoutesMu.Unlock()
 
@@ -135,7 +167,7 @@ func (u *URL) MarshalText() (text []byte, err error) {
 }
 
 func ProxyHandler(w http.ResponseWriter, r *http.Request) {
-	mux, err := findMux(r.Host)
+	mux, err := findMuxFunc(r.Host)
 	if err != nil {
 		err = E.Failure("request").
 			Subjectf("%s %s%s", r.Method, r.Host, r.URL.Path).
@@ -147,7 +179,7 @@ func ProxyHandler(w http.ResponseWriter, r *http.Request) {
 	mux.ServeHTTP(w, r)
 }
 
-func findMux(host string) (*http.ServeMux, E.NestedError) {
+func findMuxAnyDomain(host string) (*http.ServeMux, E.NestedError) {
 	hostSplit := strings.Split(host, ".")
 	n := len(hostSplit)
 	if n <= 2 {
@@ -160,23 +192,21 @@ func findMux(host string) (*http.ServeMux, E.NestedError) {
 	return nil, E.NotExist("route", sd)
 }
 
-var (
+func findMuxByDomain(domains []string) func(host string) (*http.ServeMux, E.NestedError) {
-	defaultDialer = net.Dialer{
+	return func(host string) (*http.ServeMux, E.NestedError) {
-		Timeout:   60 * time.Second,
+		var subdomain string
-		KeepAlive: 60 * time.Second,
+		for _, domain := range domains {
+			subdomain = strings.TrimSuffix(subdomain, domain)
+			if subdomain != domain {
+				break
+			}
+		}
+		if subdomain == "" { // not matched
+			return nil, E.Invalid("host", host)
+		}
+		if r, ok := httpRoutes.Load(PT.Alias(subdomain)); ok {
+			return r.mux, nil
+		}
+		return nil, E.NotExist("route", subdomain)
 	}
-	transport = &http.Transport{
+}
-		Proxy:               http.ProxyFromEnvironment,
-		DialContext:         defaultDialer.DialContext,
-		MaxIdleConnsPerHost: 1000,
-	}
-	transportNoTLS = func() *http.Transport {
-		var clone = transport.Clone()
-		clone.TLSClientConfig = &tls.Config{InsecureSkipVerify: true}
-		return clone
-	}()
-
-	httpRoutes   = F.NewMapOf[SubdomainKey, *HTTPRoute]()
-	httpRoutesMu sync.Mutex
-	globalMux    = http.NewServeMux()
-)

src/route/middleware/add_x_forwarded.go

@@ -1,7 +0,0 @@
-package middleware
-
-var AddXForwarded = &Middleware{
-	rewrite: func(r *ProxyRequest) {
-		r.SetXForwarded()
-	},
-}

src/route/middleware/forward_auth.go

@@ -0,0 +1,249 @@
+// Modified from Traefik Labs's MIT-licensed code (https://github.com/traefik/traefik/blob/master/pkg/middlewares/auth/forward.go)
+// Copyright (c) 2020-2024 Traefik Labs
+// Copyright (c) 2024 yusing
+
+package middleware
+
+import (
+	"io"
+	"net"
+	"net/http"
+	"net/url"
+	"slices"
+	"strings"
+	"time"
+
+	"github.com/sirupsen/logrus"
+	"github.com/yusing/go-proxy/common"
+	D "github.com/yusing/go-proxy/docker"
+	E "github.com/yusing/go-proxy/error"
+	gpHTTP "github.com/yusing/go-proxy/http"
+	U "github.com/yusing/go-proxy/utils"
+)
+
+type (
+	forwardAuth struct {
+		*forwardAuthOpts
+		m      *Middleware
+		client http.Client
+	}
+	forwardAuthOpts struct {
+		Address                  string
+		TrustForwardHeader       bool
+		AuthResponseHeaders      []string
+		AddAuthCookiesToResponse []string
+	}
+)
+
+const (
+	xForwardedFor    = "X-Forwarded-For"
+	xForwardedMethod = "X-Forwarded-Method"
+	xForwardedHost   = "X-Forwarded-Host"
+	xForwardedProto  = "X-Forwarded-Proto"
+	xForwardedURI    = "X-Forwarded-Uri"
+	xForwardedPort   = "X-Forwarded-Port"
+)
+
+var ForwardAuth = newForwardAuth()
+var faLogger = logrus.WithField("middleware", "ForwardAuth")
+
+func newForwardAuth() (fa *forwardAuth) {
+	fa = new(forwardAuth)
+	fa.m = new(Middleware)
+	fa.m.labelParserMap = D.ValueParserMap{
+		"trust_forward_header":         D.BoolParser,
+		"auth_response_headers":        D.YamlStringListParser,
+		"add_auth_cookies_to_response": D.YamlStringListParser,
+	}
+	fa.m.withOptions = func(optsRaw OptionsRaw, rp *ReverseProxy) (*Middleware, E.NestedError) {
+		tr, ok := rp.Transport.(*http.Transport)
+		if ok {
+			tr = tr.Clone()
+		} else {
+			tr = common.DefaultTransport.Clone()
+		}
+
+		faWithOpts := new(forwardAuth)
+		faWithOpts.forwardAuthOpts = new(forwardAuthOpts)
+		faWithOpts.client = http.Client{
+			CheckRedirect: func(r *Request, via []*Request) error {
+				return http.ErrUseLastResponse
+			},
+			Timeout:   30 * time.Second,
+			Transport: tr,
+		}
+		faWithOpts.m = &Middleware{
+			impl:   faWithOpts,
+			before: fa.forward,
+		}
+
+		err := U.Deserialize(optsRaw, faWithOpts.forwardAuthOpts)
+		if err != nil {
+			return nil, E.FailWith("set options", err)
+		}
+		_, err = E.Check(url.Parse(faWithOpts.Address))
+		if err != nil {
+			return nil, E.Invalid("address", faWithOpts.Address)
+		}
+		return faWithOpts.m, nil
+	}
+	return
+}
+
+func (fa *forwardAuth) forward(next http.Handler, w ResponseWriter, req *Request) {
+	removeHop(req.Header)
+
+	faReq, err := http.NewRequestWithContext(
+		req.Context(),
+		http.MethodGet,
+		fa.Address,
+		nil,
+	)
+	if err != nil {
+		faLogger.Debugf("new request err to %s: %s", fa.Address, err)
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	copyHeader(faReq.Header, req.Header)
+	removeHop(faReq.Header)
+
+	filterHeaders(faReq.Header, fa.AuthResponseHeaders)
+	fa.setAuthHeaders(req, faReq)
+
+	faResp, err := fa.client.Do(faReq)
+	if err != nil {
+		faLogger.Debugf("failed to call %s: %s", fa.Address, err)
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+	defer faResp.Body.Close()
+
+	body, err := io.ReadAll(faResp.Body)
+	if err != nil {
+		faLogger.Debugf("failed to read response body from %s: %s", fa.Address, err)
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	if faResp.StatusCode < http.StatusOK || faResp.StatusCode >= http.StatusMultipleChoices {
+		copyHeader(w.Header(), faResp.Header)
+		removeHop(w.Header())
+
+		redirectURL, err := faResp.Location()
+		if err != nil {
+			faLogger.Debugf("failed to get location from %s: %s", fa.Address, err)
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		} else if redirectURL.String() != "" {
+			w.Header().Set("Location", redirectURL.String())
+		}
+
+		w.WriteHeader(faResp.StatusCode)
+
+		if _, err = w.Write(body); err != nil {
+			faLogger.Debugf("failed to write response body from %s: %s", fa.Address, err)
+		}
+		return
+	}
+
+	for _, key := range fa.AuthResponseHeaders {
+		key := http.CanonicalHeaderKey(key)
+		req.Header.Del(key)
+		if len(faResp.Header[key]) > 0 {
+			req.Header[key] = append([]string(nil), faResp.Header[key]...)
+		}
+	}
+
+	req.RequestURI = req.URL.RequestURI()
+
+	authCookies := faResp.Cookies()
+
+	if len(authCookies) == 0 {
+		next.ServeHTTP(w, req)
+		return
+	}
+
+	next.ServeHTTP(gpHTTP.NewModifyResponseWriter(w, req, func(resp *Response) error {
+		fa.setAuthCookies(resp, authCookies)
+		return nil
+	}), req)
+}
+
+func (fa *forwardAuth) setAuthCookies(resp *Response, authCookies []*Cookie) {
+	if len(fa.AddAuthCookiesToResponse) == 0 {
+		return
+	}
+
+	cookies := resp.Cookies()
+	resp.Header.Del("Set-Cookie")
+
+	for _, cookie := range cookies {
+		if !slices.Contains(fa.AddAuthCookiesToResponse, cookie.Name) {
+			// this cookie is not an auth cookie, so add it back
+			resp.Header.Add("Set-Cookie", cookie.String())
+		}
+	}
+
+	for _, cookie := range authCookies {
+		if slices.Contains(fa.AddAuthCookiesToResponse, cookie.Name) {
+			// this cookie is an auth cookie, so add to resp
+			resp.Header.Add("Set-Cookie", cookie.String())
+		}
+	}
+}
+
+func (fa *forwardAuth) setAuthHeaders(req, faReq *Request) {
+	if clientIP, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
+		if fa.TrustForwardHeader {
+			if prior, ok := req.Header[xForwardedFor]; ok {
+				clientIP = strings.Join(prior, ", ") + ", " + clientIP
+			}
+		}
+		faReq.Header.Set(xForwardedFor, clientIP)
+	}
+
+	xMethod := req.Header.Get(xForwardedMethod)
+	switch {
+	case xMethod != "" && fa.TrustForwardHeader:
+		faReq.Header.Set(xForwardedMethod, xMethod)
+	case req.Method != "":
+		faReq.Header.Set(xForwardedMethod, req.Method)
+	default:
+		faReq.Header.Del(xForwardedMethod)
+	}
+
+	xfp := req.Header.Get(xForwardedProto)
+	switch {
+	case xfp != "" && fa.TrustForwardHeader:
+		faReq.Header.Set(xForwardedProto, xfp)
+	case req.TLS != nil:
+		faReq.Header.Set(xForwardedProto, "https")
+	default:
+		faReq.Header.Set(xForwardedProto, "http")
+	}
+
+	if xfp := req.Header.Get(xForwardedPort); xfp != "" && fa.TrustForwardHeader {
+		faReq.Header.Set(xForwardedPort, xfp)
+	}
+
+	xfh := req.Header.Get(xForwardedHost)
+	switch {
+	case xfh != "" && fa.TrustForwardHeader:
+		faReq.Header.Set(xForwardedHost, xfh)
+	case req.Host != "":
+		faReq.Header.Set(xForwardedHost, req.Host)
+	default:
+		faReq.Header.Del(xForwardedHost)
+	}
+
+	xfURI := req.Header.Get(xForwardedURI)
+	switch {
+	case xfURI != "" && fa.TrustForwardHeader:
+		faReq.Header.Set(xForwardedURI, xfURI)
+	case req.URL.RequestURI() != "":
+		faReq.Header.Set(xForwardedURI, req.URL.RequestURI())
+	default:
+		faReq.Header.Del(xForwardedURI)
+	}
+}

src/route/middleware/headers.go

@@ -0,0 +1,44 @@
+package middleware
+
+import (
+	"net/http"
+	"slices"
+
+	gpHTTP "github.com/yusing/go-proxy/http"
+)
+
+func removeHop(h Header) {
+	reqUpType := gpHTTP.UpgradeType(h)
+	gpHTTP.RemoveHopByHopHeaders(h)
+
+	if reqUpType != "" {
+		h.Set("Connection", "Upgrade")
+		h.Set("Upgrade", reqUpType)
+	} else {
+		h.Del("Connection")
+	}
+}
+
+func copyHeader(dst, src Header) {
+	for k, vv := range src {
+		for _, v := range vv {
+			dst.Add(k, v)
+		}
+	}
+}
+
+func filterHeaders(h Header, allowed []string) {
+	if allowed == nil {
+		return
+	}
+
+	for i := range allowed {
+		allowed[i] = http.CanonicalHeaderKey(allowed[i])
+	}
+
+	for key := range h {
+		if !slices.Contains(allowed, key) {
+			h.Del(key)
+		}
+	}
+}

src/route/middleware/middleware.go

@@ -3,33 +3,42 @@ package middleware
 import (
 	"net/http"
 
+	D "github.com/yusing/go-proxy/docker"
 	E "github.com/yusing/go-proxy/error"
-	P "github.com/yusing/go-proxy/proxy"
+	gpHTTP "github.com/yusing/go-proxy/http"
 )
 
 type (
-	ReverseProxy   = P.ReverseProxy
+	Error = E.NestedError
-	ProxyRequest   = P.ProxyRequest
+
+	ReverseProxy   = gpHTTP.ReverseProxy
+	ProxyRequest   = gpHTTP.ProxyRequest
 	Request        = http.Request
 	Response       = http.Response
 	ResponseWriter = http.ResponseWriter
+	Header         = http.Header
+	Cookie         = http.Cookie
 
-	BeforeFunc         func(w ResponseWriter, r *Request) (continue_ bool)
+	BeforeFunc         func(next http.Handler, w ResponseWriter, r *Request)
 	RewriteFunc        func(req *ProxyRequest)
 	ModifyResponseFunc func(res *Response) error
+	CloneWithOptFunc   func(opts OptionsRaw, rp *ReverseProxy) (*Middleware, E.NestedError)
 
-	MiddlewareOptionsRaw map[string]string
+	OptionsRaw = map[string]any
-	MiddlewareOptions    map[string]interface{}
+	Options    any
 
 	Middleware struct {
 		name string
 
-		before         BeforeFunc
+		before         BeforeFunc         // runs before ReverseProxy.ServeHTTP
-		rewrite        RewriteFunc
+		rewrite        RewriteFunc        // runs after ReverseProxy.Rewrite
-		modifyResponse ModifyResponseFunc
+		modifyResponse ModifyResponseFunc // runs after ReverseProxy.ModifyResponse
 
-		options         MiddlewareOptions
+		transport http.RoundTripper
-		validateOptions func(opts MiddlewareOptionsRaw) (MiddlewareOptions, E.NestedError)
+
+		withOptions    CloneWithOptFunc
+		labelParserMap D.ValueParserMap
+		impl           any
 	}
 )
 
@@ -41,41 +50,32 @@ func (m *Middleware) String() string {
 	return m.name
 }
 
-func (m *Middleware) WithOptions(optsRaw MiddlewareOptionsRaw) (*Middleware, E.NestedError) {
+func (m *Middleware) WithOptionsClone(optsRaw OptionsRaw, rp *ReverseProxy) (*Middleware, E.NestedError) {
-	if len(optsRaw) == 0 {
+	if len(optsRaw) != 0 && m.withOptions != nil {
-		return m, nil
+		if mWithOpt, err := m.withOptions(optsRaw, rp); err != nil {
-	}
-
-	var opts MiddlewareOptions
-	var err E.NestedError
-
-	if m.validateOptions != nil {
-		if opts, err = m.validateOptions(optsRaw); err != nil {
 			return nil, err
+		} else {
+			return mWithOpt, nil
 		}
 	}
 
-	return &Middleware{
+	// WithOptionsClone is called only once
-		name:           m.name,
+	// set withOptions and labelParser will not be used after that
-		before:         m.before,
+	return &Middleware{m.name, m.before, m.rewrite, m.modifyResponse, m.transport, nil, nil, m.impl}, nil
-		rewrite:        m.rewrite,
-		modifyResponse: m.modifyResponse,
-		options:        opts,
-	}, nil
 }
 
-// TODO: check conflict
+// TODO: check conflict or duplicates
-func PatchReverseProxy(rp ReverseProxy, middlewares map[string]MiddlewareOptionsRaw) (out ReverseProxy, err E.NestedError) {
+func PatchReverseProxy(rp *ReverseProxy, middlewares map[string]OptionsRaw) (res E.NestedError) {
-	out = rp
-
 	befores := make([]BeforeFunc, 0, len(middlewares))
 	rewrites := make([]RewriteFunc, 0, len(middlewares))
 	modifyResponses := make([]ModifyResponseFunc, 0, len(middlewares))
 
 	invalidM := E.NewBuilder("invalid middlewares")
 	invalidOpts := E.NewBuilder("invalid options")
-	defer invalidM.Add(invalidOpts.Build())
+	defer func() {
-	defer invalidM.To(&err)
+		invalidM.Add(invalidOpts.Build())
+		invalidM.To(&res)
+	}()
 
 	for name, opts := range middlewares {
 		m, ok := Get(name)
@@ -83,7 +83,8 @@ func PatchReverseProxy(rp ReverseProxy, middlewares map[string]MiddlewareOptions
 			invalidM.Addf("%s", name)
 			continue
 		}
-		m, err = m.WithOptions(opts)
+
+		m, err := m.WithOptionsClone(opts, rp)
 		if err != nil {
 			invalidOpts.Add(err.Subject(name))
 			continue
@@ -103,25 +104,37 @@ func PatchReverseProxy(rp ReverseProxy, middlewares map[string]MiddlewareOptions
 		return
 	}
 
-	if len(befores) > 0 {
+	origServeHTTP := rp.ServeHTTP
-		rp.ServeHTTP = func(w ResponseWriter, r *Request) {
+	for i, before := range befores {
-			for _, before := range befores {
+		if i < len(befores)-1 {
-				if !before(w, r) {
+			rp.ServeHTTP = func(w ResponseWriter, r *Request) {
-					return
+				before(rp.ServeHTTP, w, r)
-				}
+			}
+		} else {
+			rp.ServeHTTP = func(w ResponseWriter, r *Request) {
+				before(origServeHTTP, w, r)
 			}
-			rp.ServeHTTP(w, r)
 		}
 	}
+
 	if len(rewrites) > 0 {
+		origRewrite := rp.Rewrite
 		rp.Rewrite = func(req *ProxyRequest) {
+			if origRewrite != nil {
+				origRewrite(req)
+			}
 			for _, rewrite := range rewrites {
 				rewrite(req)
 			}
 		}
 	}
+
 	if len(modifyResponses) > 0 {
+		origModifyResponse := rp.ModifyResponse
 		rp.ModifyResponse = func(res *Response) error {
+			if origModifyResponse != nil {
+				return origModifyResponse(res)
+			}
 			for _, modifyResponse := range modifyResponses {
 				if err := modifyResponse(res); err != nil {
 					return err

src/route/middleware/middlewares.go

@@ -3,14 +3,11 @@ package middleware
 import (
 	"fmt"
 	"strings"
+
+	D "github.com/yusing/go-proxy/docker"
 )
 
-var middlewares = map[string]*Middleware{
+var middlewares map[string]*Middleware
-	"set_x_forwarded":      SetXForwarded, // nginx
-	"add_x_forwarded":      AddXForwarded, // nginx
-	"trust_forward_header": AddXForwarded, // traefik alias
-	"redirect_http":        RedirectHTTP,
-}
 
 func Get(name string) (middleware *Middleware, ok bool) {
 	middleware, ok = middlewares[name]
@@ -18,10 +15,23 @@ func Get(name string) (middleware *Middleware, ok bool) {
 }
 
 // initialize middleware names
-var _ = func() (_ bool) {
+func init() {
+	middlewares = map[string]*Middleware{
+		"set_x_forwarded": SetXForwarded,
+		"add_x_forwarded": AddXForwarded,
+		"redirect_http":   RedirectHTTP,
+		"forward_auth":    ForwardAuth.m,
+		"modify_response": ModifyResponse.m,
+		"modify_request":  ModifyRequest.m,
+	}
 	names := make(map[*Middleware][]string)
 	for name, m := range middlewares {
 		names[m] = append(names[m], name)
+		// register middleware name to docker label parsr
+		// in order to parse middleware_name.option=value into correct type
+		if m.labelParserMap != nil {
+			D.RegisterNamespace(name, m.labelParserMap)
+		}
 	}
 	for m, names := range names {
 		if len(names) > 1 {
@@ -30,5 +40,4 @@ var _ = func() (_ bool) {
 			m.name = names[0]
 		}
 	}
-	return
+}
-}()

src/route/middleware/modify_request.go

@@ -0,0 +1,58 @@
+package middleware
+
+import (
+	D "github.com/yusing/go-proxy/docker"
+	E "github.com/yusing/go-proxy/error"
+	U "github.com/yusing/go-proxy/utils"
+)
+
+type (
+	modifyRequest struct {
+		*modifyRequestOpts
+		m *Middleware
+	}
+	// order: set_headers -> add_headers -> hide_headers
+	modifyRequestOpts struct {
+		SetHeaders  map[string]string
+		AddHeaders  map[string]string
+		HideHeaders []string
+	}
+)
+
+var ModifyRequest = newModifyRequest()
+
+func newModifyRequest() (mr *modifyRequest) {
+	mr = new(modifyRequest)
+	mr.m = new(Middleware)
+	mr.m.labelParserMap = D.ValueParserMap{
+		"set_headers":  D.YamlLikeMappingParser(true),
+		"add_headers":  D.YamlLikeMappingParser(true),
+		"hide_headers": D.YamlStringListParser,
+	}
+	mr.m.withOptions = func(optsRaw OptionsRaw, rp *ReverseProxy) (*Middleware, E.NestedError) {
+		mrWithOpts := new(modifyRequest)
+		mrWithOpts.m = &Middleware{
+			impl:    mrWithOpts,
+			rewrite: mrWithOpts.modifyRequest,
+		}
+		mrWithOpts.modifyRequestOpts = new(modifyRequestOpts)
+		err := U.Deserialize(optsRaw, mrWithOpts.modifyRequestOpts)
+		if err != nil {
+			return nil, E.FailWith("set options", err)
+		}
+		return mrWithOpts.m, nil
+	}
+	return
+}
+
+func (mr *modifyRequest) modifyRequest(req *ProxyRequest) {
+	for k, v := range mr.SetHeaders {
+		req.Out.Header.Set(k, v)
+	}
+	for k, v := range mr.AddHeaders {
+		req.Out.Header.Add(k, v)
+	}
+	for _, k := range mr.HideHeaders {
+		req.Out.Header.Del(k)
+	}
+}

src/route/middleware/modify_request_test.go

@@ -0,0 +1,34 @@
+package middleware
+
+import (
+	"slices"
+	"testing"
+
+	. "github.com/yusing/go-proxy/utils/testing"
+)
+
+func TestSetModifyRequest(t *testing.T) {
+	opts := OptionsRaw{
+		"set_headers":  map[string]string{"User-Agent": "go-proxy/v0.5.0"},
+		"add_headers":  map[string]string{"Accept-Encoding": "test-value"},
+		"hide_headers": []string{"Accept"},
+	}
+
+	t.Run("set_options", func(t *testing.T) {
+		mr, err := ModifyRequest.m.WithOptionsClone(opts, nil)
+		ExpectNoError(t, err.Error())
+		ExpectDeepEqual(t, mr.impl.(*modifyRequest).SetHeaders, opts["set_headers"].(map[string]string))
+		ExpectDeepEqual(t, mr.impl.(*modifyRequest).AddHeaders, opts["add_headers"].(map[string]string))
+		ExpectDeepEqual(t, mr.impl.(*modifyRequest).HideHeaders, opts["hide_headers"].([]string))
+	})
+
+	t.Run("request_headers", func(t *testing.T) {
+		result, err := newMiddlewareTest(ModifyRequest.m, &testArgs{
+			middlewareOpt: opts,
+		})
+		ExpectNoError(t, err.Error())
+		ExpectEqual(t, result.RequestHeaders.Get("User-Agent"), "go-proxy/v0.5.0")
+		ExpectTrue(t, slices.Contains(result.RequestHeaders.Values("Accept-Encoding"), "test-value"))
+		ExpectEqual(t, result.RequestHeaders.Get("Accept"), "")
+	})
+}

src/route/middleware/modify_response.go

@@ -0,0 +1,61 @@
+package middleware
+
+import (
+	"net/http"
+
+	D "github.com/yusing/go-proxy/docker"
+	E "github.com/yusing/go-proxy/error"
+	U "github.com/yusing/go-proxy/utils"
+)
+
+type (
+	modifyResponse struct {
+		*modifyResponseOpts
+		m *Middleware
+	}
+	// order: set_headers -> add_headers -> hide_headers
+	modifyResponseOpts struct {
+		SetHeaders  map[string]string
+		AddHeaders  map[string]string
+		HideHeaders []string
+	}
+)
+
+var ModifyResponse = newModifyResponse()
+
+func newModifyResponse() (mr *modifyResponse) {
+	mr = new(modifyResponse)
+	mr.m = new(Middleware)
+	mr.m.labelParserMap = D.ValueParserMap{
+		"set_headers":  D.YamlLikeMappingParser(true),
+		"add_headers":  D.YamlLikeMappingParser(true),
+		"hide_headers": D.YamlStringListParser,
+	}
+	mr.m.withOptions = func(optsRaw OptionsRaw, rp *ReverseProxy) (*Middleware, E.NestedError) {
+		mrWithOpts := new(modifyResponse)
+		mrWithOpts.m = &Middleware{
+			impl:           mrWithOpts,
+			modifyResponse: mrWithOpts.modifyResponse,
+		}
+		mrWithOpts.modifyResponseOpts = new(modifyResponseOpts)
+		err := U.Deserialize(optsRaw, mrWithOpts.modifyResponseOpts)
+		if err != nil {
+			return nil, E.FailWith("set options", err)
+		}
+		return mrWithOpts.m, nil
+	}
+	return
+}
+
+func (mr *modifyResponse) modifyResponse(resp *http.Response) error {
+	for k, v := range mr.SetHeaders {
+		resp.Header.Set(k, v)
+	}
+	for k, v := range mr.AddHeaders {
+		resp.Header.Add(k, v)
+	}
+	for _, k := range mr.HideHeaders {
+		resp.Header.Del(k)
+	}
+	return nil
+}

src/route/middleware/modify_response_test.go

@@ -0,0 +1,35 @@
+package middleware
+
+import (
+	"slices"
+	"testing"
+
+	. "github.com/yusing/go-proxy/utils/testing"
+)
+
+func TestSetModifyResponse(t *testing.T) {
+	opts := OptionsRaw{
+		"set_headers":  map[string]string{"User-Agent": "go-proxy/v0.5.0"},
+		"add_headers":  map[string]string{"Accept-Encoding": "test-value"},
+		"hide_headers": []string{"Accept"},
+	}
+
+	t.Run("set_options", func(t *testing.T) {
+		mr, err := ModifyResponse.m.WithOptionsClone(opts, nil)
+		ExpectNoError(t, err.Error())
+		ExpectDeepEqual(t, mr.impl.(*modifyResponse).SetHeaders, opts["set_headers"].(map[string]string))
+		ExpectDeepEqual(t, mr.impl.(*modifyResponse).AddHeaders, opts["add_headers"].(map[string]string))
+		ExpectDeepEqual(t, mr.impl.(*modifyResponse).HideHeaders, opts["hide_headers"].([]string))
+	})
+
+	t.Run("request_headers", func(t *testing.T) {
+		result, err := newMiddlewareTest(ModifyResponse.m, &testArgs{
+			middlewareOpt: opts,
+		})
+		ExpectNoError(t, err.Error())
+		ExpectEqual(t, result.ResponseHeaders.Get("User-Agent"), "go-proxy/v0.5.0")
+		t.Log(result.ResponseHeaders.Get("Accept-Encoding"))
+		ExpectTrue(t, slices.Contains(result.ResponseHeaders.Values("Accept-Encoding"), "test-value"))
+		ExpectEqual(t, result.ResponseHeaders.Get("Accept"), "")
+	})
+}

src/route/middleware/redirect_http.go

@@ -7,14 +7,13 @@ import (
 )
 
 var RedirectHTTP = &Middleware{
-	before: func(w ResponseWriter, r *Request) (continue_ bool) {
+	before: func(next http.Handler, w ResponseWriter, r *Request) {
 		if r.TLS == nil {
 			r.URL.Scheme = "https"
-			r.URL.Host = r.URL.Hostname() + common.ProxyHTTPSPort
+			r.URL.Host = r.URL.Hostname() + ":" + common.ProxyHTTPSPort
 			http.Redirect(w, r, r.URL.String(), http.StatusTemporaryRedirect)
-		} else {
+			return
-			continue_ = true
 		}
-		return
+		next.ServeHTTP(w, r)
 	},
 }

src/route/middleware/redirect_http_test.go

@@ -0,0 +1,26 @@
+package middleware
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/yusing/go-proxy/common"
+	. "github.com/yusing/go-proxy/utils/testing"
+)
+
+func TestRedirectToHTTPs(t *testing.T) {
+	result, err := newMiddlewareTest(RedirectHTTP, &testArgs{
+		scheme: "http",
+	})
+	ExpectNoError(t, err.Error())
+	ExpectEqual(t, result.ResponseStatus, http.StatusTemporaryRedirect)
+	ExpectEqual(t, result.ResponseHeaders.Get("Location"), "https://"+testHost+":"+common.ProxyHTTPSPort)
+}
+
+func TestNoRedirect(t *testing.T) {
+	result, err := newMiddlewareTest(RedirectHTTP, &testArgs{
+		scheme: "https",
+	})
+	ExpectNoError(t, err.Error())
+	ExpectEqual(t, result.ResponseStatus, http.StatusOK)
+}

src/route/middleware/set_x_forwarded.go

@@ -1,10 +0,0 @@
-package middleware
-
-var SetXForwarded = &Middleware{
-	rewrite: func(r *ProxyRequest) {
-		r.Out.Header.Del("X-Forwarded-For")
-		r.Out.Header.Del("X-Forwarded-Host")
-		r.Out.Header.Del("X-Forwarded-Proto")
-		r.SetXForwarded()
-	},
-}

src/route/middleware/test_data/sample_headers.json

@@ -0,0 +1,17 @@
+{
+    "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7",
+    "Accept-Encoding": "gzip, deflate, br, zstd",
+    "Accept-Language": "en,zh-HK;q=0.9,zh-TW;q=0.8,zh-CN;q=0.7,zh;q=0.6",
+    "Dnt": "1",
+    "Host": "localhost",
+    "Priority": "u=0, i",
+    "Sec-Ch-Ua": "\"Chromium\";v=\"129\", \"Not=A?Brand\";v=\"8\"",
+    "Sec-Ch-Ua-Mobile": "?0",
+    "Sec-Ch-Ua-Platform": "\"Windows\"",
+    "Sec-Fetch-Dest": "document",
+    "Sec-Fetch-Mode": "navigate",
+    "Sec-Fetch-Site": "none",
+    "Sec-Fetch-User": "?1",
+    "Upgrade-Insecure-Requests": "1",
+    "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/129.0.0.0 Safari/537.36"
+}

src/route/middleware/test_utils.go

@@ -0,0 +1,125 @@
+package middleware
+
+import (
+	"bytes"
+	_ "embed"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+
+	E "github.com/yusing/go-proxy/error"
+	gpHTTP "github.com/yusing/go-proxy/http"
+)
+
+//go:embed test_data/sample_headers.json
+var testHeadersRaw []byte
+var testHeaders http.Header
+
+const testHost = "example.com"
+
+func init() {
+	tmp := map[string]string{}
+	err := json.Unmarshal(testHeadersRaw, &tmp)
+	if err != nil {
+		panic(err)
+	}
+	testHeaders = http.Header{}
+	for k, v := range tmp {
+		testHeaders.Set(k, v)
+	}
+}
+
+type requestHeaderRecorder struct {
+	parent     http.RoundTripper
+	reqHeaders http.Header
+}
+
+func (rt *requestHeaderRecorder) RoundTrip(req *http.Request) (*http.Response, error) {
+	rt.reqHeaders = req.Header
+	if rt.parent != nil {
+		return rt.parent.RoundTrip(req)
+	}
+	return &http.Response{
+		StatusCode: http.StatusOK,
+		Header:     testHeaders,
+		Body:       io.NopCloser(bytes.NewBufferString("OK")),
+		Request:    req,
+	}, nil
+}
+
+type TestResult struct {
+	RequestHeaders  http.Header
+	ResponseHeaders http.Header
+	ResponseStatus  int
+	Data            []byte
+}
+
+type testArgs struct {
+	middlewareOpt OptionsRaw
+	proxyURL      string
+	body          []byte
+	scheme        string
+}
+
+func newMiddlewareTest(middleware *Middleware, args *testArgs) (*TestResult, E.NestedError) {
+	var body io.Reader
+	var rt = new(requestHeaderRecorder)
+	var proxyURL *url.URL
+	var requestTarget string
+	var err error
+
+	if args == nil {
+		args = new(testArgs)
+	}
+
+	if args.body != nil {
+		body = bytes.NewReader(args.body)
+	}
+
+	if args.scheme == "" || args.scheme == "http" {
+		requestTarget = "http://" + testHost
+	} else if args.scheme == "https" {
+		requestTarget = "https://" + testHost
+	} else {
+		panic("typo?")
+	}
+
+	req := httptest.NewRequest(http.MethodGet, requestTarget, body)
+	w := httptest.NewRecorder()
+
+	if args.scheme == "https" && req.TLS == nil {
+		panic("bug occurred")
+	}
+
+	if args.proxyURL != "" {
+		proxyURL, err = url.Parse(args.proxyURL)
+		if err != nil {
+			return nil, E.From(err)
+		}
+		rt.parent = http.DefaultTransport
+	} else {
+		proxyURL, _ = url.Parse("https://" + testHost) // dummy url, no actual effect
+	}
+	rp := gpHTTP.NewReverseProxy(proxyURL, rt)
+	setOptErr := PatchReverseProxy(rp, map[string]OptionsRaw{
+		middleware.name: args.middlewareOpt,
+	})
+	if setOptErr != nil {
+		return nil, setOptErr
+	}
+	rp.ServeHTTP(w, req)
+	resp := w.Result()
+	defer resp.Body.Close()
+	data, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, E.From(err)
+	}
+	return &TestResult{
+		RequestHeaders:  rt.reqHeaders,
+		ResponseHeaders: resp.Header,
+		ResponseStatus:  resp.StatusCode,
+		Data:            data,
+	}, nil
+}

src/route/middleware/x_forwarded.go

@@ -0,0 +1,9 @@
+package middleware
+
+var AddXForwarded = &Middleware{
+	rewrite: (*ProxyRequest).AddXForwarded,
+}
+
+var SetXForwarded = &Middleware{
+	rewrite: (*ProxyRequest).SetXForwarded,
+}

src/server/server.go

@@ -84,6 +84,11 @@ func NewServer(opt Options) (s *server) {
 	}
 }
 
+// Start will start the http and https servers.
+//
+// If both are not set, this does nothing.
+//
+// Start() is non-blocking
 func (s *server) Start() {
 	if s.http == nil && s.https == nil {
 		return

src/utils/serialization.go

@@ -106,7 +106,7 @@ func Serialize(data any) (SerializedObject, E.NestedError) {
 	return result, nil
 }
 
-func Deserialize(src map[string]any, target any) E.NestedError {
+func Deserialize(src SerializedObject, target any) E.NestedError {
 	// convert data fields to lower no-snake
 	// convert target fields to lower
 	// then check if the field of data is in the target
@@ -117,6 +117,10 @@ func Deserialize(src map[string]any, target any) E.NestedError {
 		snakeCaseField := strings.ToLower(field.Name)
 		mapping[snakeCaseField] = field.Name
 	}
+	tValue := reflect.ValueOf(target)
+	if tValue.IsZero() {
+		return E.Invalid("value", "nil")
+	}
 	for k, v := range src {
 		kCleaned := toLowerNoSnake(k)
 		if fieldName, ok := mapping[kCleaned]; ok {
@@ -150,13 +154,13 @@ func Deserialize(src map[string]any, target any) E.NestedError {
 					}
 					prop.Set(propNew)
 				default:
-					return E.Unsupported("field", k).Extraf("type=%s", propType)
+					return E.Invalid("conversion", k).Extraf("from %s to %s", vType, propType)
 				}
 			} else {
-				return E.Unsupported("field", k).Extraf("type=%s", propType)
+				return E.Unsupported("field", k).Extraf("type %s is not settable", propType)
 			}
 		} else {
-			return E.Failure("unknown field").With(k)
+			return E.Unexpected("field", k)
 		}
 	}
 

src/utils/testing/testing.go

@@ -38,6 +38,17 @@ func ExpectEqual[T comparable](t *testing.T, got T, want T) {
 	}
 }
 
+func ExpectEqualAny[T comparable](t *testing.T, got T, wants []T) {
+	t.Helper()
+	for _, want := range wants {
+		if got == want {
+			return
+		}
+	}
+	t.Errorf("expected any of:\n%v, got\n%v", wants, got)
+	t.FailNow()
+}
+
 func ExpectDeepEqual[T any](t *testing.T, got T, want T) {
 	t.Helper()
 	if !reflect.DeepEqual(got, want) {