fix: loosen agent version checking

- warn instead of error when version mismatch
- check for major version only
- better version parsing

agent/pkg/agent/config.go

@@ -80,14 +80,6 @@ func (cfg *AgentConfig) Parse(addr string) error {
 	return nil
 }
 
-func withoutBuildTime(version string) string {
-	return strings.Split(version, "-")[0]
-}
-
-func checkVersion(a, b string) bool {
-	return withoutBuildTime(a) == withoutBuildTime(b)
-}
-
 func (cfg *AgentConfig) StartWithCerts(parent task.Parent, ca, crt, key []byte) error {
 	clientCert, err := tls.X509KeyPair(crt, key)
 	if err != nil {
@@ -113,18 +105,6 @@ func (cfg *AgentConfig) StartWithCerts(parent task.Parent, ca, crt, key []byte)
 	ctx, cancel := context.WithTimeout(parent.Context(), 5*time.Second)
 	defer cancel()
 
-	// check agent version
-	version, _, err := cfg.Fetch(ctx, EndpointVersion)
-	if err != nil {
-		return err
-	}
-
-	versionStr := string(version)
-	// skip version check for dev versions
-	if strings.HasPrefix(versionStr, "v") && !checkVersion(versionStr, pkg.GetVersion()) {
-		return gperr.Errorf("agent version mismatch: server: %s, agent: %s", pkg.GetVersion(), versionStr)
-	}
-
 	// get agent name
 	name, _, err := cfg.Fetch(ctx, EndpointName)
 	if err != nil {
@@ -132,8 +112,21 @@ func (cfg *AgentConfig) StartWithCerts(parent task.Parent, ca, crt, key []byte)
 	}
 
 	cfg.name = string(name)
+
 	cfg.l = logging.With().Str("agent", cfg.name).Logger()
 
+	// check agent version
+	agentVersionBytes, _, err := cfg.Fetch(ctx, EndpointVersion)
+	if err != nil {
+		return err
+	}
+
+	agentVersion := string(agentVersionBytes)
+
+	if pkg.GetVersion().IsNewerMajorThan(pkg.ParseVersion(agentVersion)) {
+		logging.Warn().Msgf("agent %s major version mismatch: server: %s, agent: %s", cfg.name, pkg.GetVersion(), agentVersion)
+	}
+
 	logging.Info().Msgf("agent %q initialized", cfg.name)
 	return nil
 }

agent/pkg/handler/handler.go

@@ -37,9 +37,7 @@ func NewAgentHandler() http.Handler {
 	mux := ServeMux{http.NewServeMux()}
 
 	mux.HandleFunc(agent.EndpointProxyHTTP+"/{path...}", ProxyHTTP)
-	mux.HandleMethods("GET", agent.EndpointVersion, func(w http.ResponseWriter, r *http.Request) {
-		w.Write([]byte(pkg.GetVersion()))
-	})
+	mux.HandleMethods("GET", agent.EndpointVersion, pkg.GetVersionHTTPHandler())
 	mux.HandleMethods("GET", agent.EndpointName, func(w http.ResponseWriter, r *http.Request) {
 		fmt.Fprint(w, env.AgentName)
 	})

internal/api/handler.go

@@ -14,6 +14,7 @@ import (
 	"github.com/yusing/go-proxy/internal/metrics/uptime"
 	"github.com/yusing/go-proxy/internal/net/gphttp/httpheaders"
 	"github.com/yusing/go-proxy/internal/utils/strutils"
+	"github.com/yusing/go-proxy/pkg"
 )
 
 type (
@@ -65,7 +66,7 @@ func (mux ServeMux) HandleFunc(methods, endpoint string, h any, requireAuth ...b
 func NewHandler(cfg config.ConfigInstance) http.Handler {
 	mux := ServeMux{http.NewServeMux(), cfg}
 	mux.HandleFunc("GET", "/v1", v1.Index)
-	mux.HandleFunc("GET", "/v1/version", v1.GetVersion)
+	mux.HandleFunc("GET", "/v1/version", pkg.GetVersionHTTPHandler())
 
 	mux.HandleFunc("GET", "/v1/stats", v1.Stats, true)
 	mux.HandleFunc("POST", "/v1/reload", v1.Reload, true)

internal/api/v1/version.go

@@ -1,12 +0,0 @@
-package v1
-
-import (
-	"net/http"
-
-	"github.com/yusing/go-proxy/internal/net/gphttp"
-	"github.com/yusing/go-proxy/pkg"
-)
-
-func GetVersion(w http.ResponseWriter, r *http.Request) {
-	gphttp.WriteBody(w, []byte(pkg.GetVersion()))
-}

internal/watcher/health/monitor/http.go

@@ -53,7 +53,7 @@ func (mon *HTTPHealthMonitor) CheckHealth() (result *health.HealthCheckResult, e
 	}
 	req.Close = true
 	req.Header.Set("Connection", "close")
-	req.Header.Set("User-Agent", "GoDoxy/"+pkg.GetVersion())
+	req.Header.Set("User-Agent", "GoDoxy/"+pkg.GetVersion().String())
 
 	start := time.Now()
 	resp, respErr := pinger.Do(req)

pkg/version.go

@@ -1,7 +1,117 @@
 package pkg
 
-var version = "unset"
+import (
+	"fmt"
+	"net/http"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
 
-func GetVersion() string {
-	return version
+	"github.com/yusing/go-proxy/internal/common"
+	"github.com/yusing/go-proxy/internal/logging"
+)
+
+func GetVersion() Version {
+	return currentVersion
+}
+
+func GetLastVersion() Version {
+	return lastVersion
+}
+
+func GetVersionHTTPHandler() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		w.Write([]byte(GetVersion().String()))
+	}
+}
+
+func init() {
+	currentVersion = ParseVersion(version)
+
+	// ignore errors
+	versionFile := filepath.Join(common.DataDir, "version")
+	var lastVersionStr string
+	f, err := os.OpenFile(versionFile, os.O_RDWR|os.O_CREATE, 0o644)
+	if err == nil {
+		_, err = fmt.Fscanf(f, "%s", &lastVersionStr)
+		lastVersion = ParseVersion(lastVersionStr)
+	}
+	if err != nil && !os.IsNotExist(err) {
+		logging.Warn().Err(err).Msg("failed to read version file")
+		return
+	}
+	if err := f.Truncate(0); err != nil {
+		logging.Warn().Err(err).Msg("failed to truncate version file")
+		return
+	}
+	_, err = f.WriteString(version)
+	if err != nil {
+		logging.Warn().Err(err).Msg("failed to save version file")
+		return
+	}
+}
+
+type Version struct{ Generation, Major, Minor int }
+
+func Ver(major, minor, patch int) Version {
+	return Version{major, minor, patch}
+}
+
+func (v Version) String() string {
+	return fmt.Sprintf("%d.%d.%d", v.Generation, v.Major, v.Minor)
+}
+
+func (v Version) MarshalText() ([]byte, error) {
+	return []byte(v.String()), nil
+}
+
+func (v Version) IsNewerMajorThan(other Version) bool {
+	if v.Generation != other.Generation {
+		return v.Generation > other.Generation
+	}
+	return v.Major > other.Major
+}
+
+func (v Version) IsEqual(other Version) bool {
+	return v.Generation == other.Generation && v.Major == other.Major && v.Minor == other.Minor
+}
+
+var (
+	version        = "unset"
+	currentVersion Version
+	lastVersion    Version
+)
+
+var versionRegex = regexp.MustCompile(`^v(\d+)\.(\d+)\.(\d+)(\-\w+)?$`)
+
+func ParseVersion(v string) (ver Version) {
+	if v == "" {
+		return
+	}
+
+	if !versionRegex.MatchString(v) { // likely feature branch (e.g. feat/some-feature)
+		return
+	}
+
+	v = strings.Split(v, "-")[0]
+	v = strings.TrimPrefix(v, "v")
+	parts := strings.Split(v, ".")
+	if len(parts) != 3 {
+		return
+	}
+	major, err := strconv.Atoi(parts[0])
+	if err != nil {
+		return
+	}
+	minor, err := strconv.Atoi(parts[1])
+	if err != nil {
+		return
+	}
+	patch, err := strconv.Atoi(parts[2])
+	if err != nil {
+		return
+	}
+	return Ver(major, minor, patch)
 }