restructured the project to comply community guideline, for others check release note

internal/api/handler.go

@@ -0,0 +1,57 @@
+package api
+
+import (
+	"fmt"
+	"net/http"
+
+	v1 "github.com/yusing/go-proxy/internal/api/v1"
+	"github.com/yusing/go-proxy/internal/api/v1/error_page"
+	. "github.com/yusing/go-proxy/internal/api/v1/utils"
+	"github.com/yusing/go-proxy/internal/common"
+	"github.com/yusing/go-proxy/internal/config"
+)
+
+type ServeMux struct{ *http.ServeMux }
+
+func NewServeMux() ServeMux {
+	return ServeMux{http.NewServeMux()}
+}
+
+func (mux ServeMux) HandleFunc(method, endpoint string, handler http.HandlerFunc) {
+	mux.ServeMux.HandleFunc(fmt.Sprintf("%s %s", method, endpoint), checkHost(handler))
+}
+
+func NewHandler(cfg *config.Config) http.Handler {
+	mux := NewServeMux()
+	mux.HandleFunc("GET", "/v1", v1.Index)
+	mux.HandleFunc("GET", "/v1/checkhealth", wrap(cfg, v1.CheckHealth))
+	mux.HandleFunc("HEAD", "/v1/checkhealth", wrap(cfg, v1.CheckHealth))
+	mux.HandleFunc("POST", "/v1/reload", wrap(cfg, v1.Reload))
+	mux.HandleFunc("GET", "/v1/list", wrap(cfg, v1.List))
+	mux.HandleFunc("GET", "/v1/list/{what}", wrap(cfg, v1.List))
+	mux.HandleFunc("GET", "/v1/file", v1.GetFileContent)
+	mux.HandleFunc("GET", "/v1/file/{filename}", v1.GetFileContent)
+	mux.HandleFunc("POST", "/v1/file/{filename}", v1.SetFileContent)
+	mux.HandleFunc("PUT", "/v1/file/{filename}", v1.SetFileContent)
+	mux.HandleFunc("GET", "/v1/stats", wrap(cfg, v1.Stats))
+	mux.HandleFunc("GET", "/v1/error_page", error_page.GetHandleFunc())
+	return mux
+}
+
+// allow only requests to API server with host matching common.APIHTTPAddr
+func checkHost(f http.HandlerFunc) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if r.Host != common.APIHTTPAddr {
+			Logger.Warnf("invalid request to API server with host: %s, expected: %s", r.Host, common.APIHTTPAddr)
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+		f(w, r)
+	}
+}
+
+func wrap(cfg *config.Config, f func(cfg *config.Config, w http.ResponseWriter, r *http.Request)) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		f(cfg, w, r)
+	}
+}

internal/api/v1/checkhealth.go

@@ -0,0 +1,42 @@
+package v1
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+
+	U "github.com/yusing/go-proxy/internal/api/v1/utils"
+	"github.com/yusing/go-proxy/internal/config"
+	R "github.com/yusing/go-proxy/internal/route"
+)
+
+func CheckHealth(cfg *config.Config, w http.ResponseWriter, r *http.Request) {
+	target := r.FormValue("target")
+	if target == "" {
+		U.HandleErr(w, r, U.ErrMissingKey("target"), http.StatusBadRequest)
+		return
+	}
+
+	var ok bool
+	route := cfg.FindRoute(target)
+
+	switch {
+	case route == nil:
+		U.HandleErr(w, r, U.ErrNotFound("target", target), http.StatusNotFound)
+		return
+	case route.Type() == R.RouteTypeReverseProxy:
+		ok = U.IsSiteHealthy(route.URL().String())
+	case route.Type() == R.RouteTypeStream:
+		entry := route.Entry()
+		ok = U.IsStreamHealthy(
+			strings.Split(entry.Scheme, ":")[1], // target scheme
+			fmt.Sprintf("%s:%v", entry.Host, strings.Split(entry.Port, ":")[1]),
+		)
+	}
+
+	if ok {
+		w.WriteHeader(http.StatusOK)
+	} else {
+		w.WriteHeader(http.StatusRequestTimeout)
+	}
+}

internal/api/v1/error_page/error_page.go

@@ -0,0 +1,88 @@
+package error_page
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"path"
+	"sync"
+
+	api "github.com/yusing/go-proxy/internal/api/v1/utils"
+	"github.com/yusing/go-proxy/internal/common"
+	U "github.com/yusing/go-proxy/internal/utils"
+	F "github.com/yusing/go-proxy/internal/utils/functional"
+	W "github.com/yusing/go-proxy/internal/watcher"
+	"github.com/yusing/go-proxy/internal/watcher/events"
+)
+
+const errPagesBasePath = common.ErrorPagesBasePath
+
+var setup = sync.OnceFunc(func() {
+	dirWatcher = W.NewDirectoryWatcher(context.Background(), errPagesBasePath)
+	loadContent()
+	go watchDir()
+})
+
+func GetStaticFile(filename string) ([]byte, bool) {
+	return fileContentMap.Load(filename)
+}
+
+// try <statusCode>.html -> 404.html -> not ok
+func GetErrorPageByStatus(statusCode int) (content []byte, ok bool) {
+	content, ok = fileContentMap.Load(fmt.Sprintf("%d.html", statusCode))
+	if !ok && statusCode != 404 {
+		return fileContentMap.Load("404.html")
+	}
+	return
+}
+
+func loadContent() {
+	files, err := U.ListFiles(errPagesBasePath, 0)
+	if err != nil {
+		api.Logger.Error(err)
+		return
+	}
+	for _, file := range files {
+		if fileContentMap.Has(file) {
+			continue
+		}
+		content, err := os.ReadFile(file)
+		if err != nil {
+			api.Logger.Errorf("failed to read error page resource %s: %s", file, err)
+			continue
+		}
+		file = path.Base(file)
+		api.Logger.Infof("error page resource %s loaded", file)
+		fileContentMap.Store(file, content)
+	}
+}
+
+func watchDir() {
+	eventCh, errCh := dirWatcher.Events(context.Background())
+	for {
+		select {
+		case event, ok := <-eventCh:
+			if !ok {
+				return
+			}
+			filename := event.ActorName
+			switch event.Action {
+			case events.ActionFileWritten:
+				fileContentMap.Delete(filename)
+				loadContent()
+			case events.ActionFileDeleted:
+				fileContentMap.Delete(filename)
+				api.Logger.Infof("error page resource %s deleted", filename)
+			case events.ActionFileRenamed:
+				api.Logger.Infof("error page resource %s deleted", filename)
+				fileContentMap.Delete(filename)
+				loadContent()
+			}
+		case err := <-errCh:
+			api.Logger.Errorf("error watching error page directory: %s", err)
+		}
+	}
+}
+
+var dirWatcher W.Watcher
+var fileContentMap = F.NewMapOf[string, []byte]()

internal/api/v1/error_page/http_handler.go

@@ -0,0 +1,25 @@
+package error_page
+
+import "net/http"
+
+func GetHandleFunc() http.HandlerFunc {
+	setup()
+	return serveHTTP
+}
+
+func serveHTTP(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodGet {
+		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+	if r.URL.Path == "/" {
+		http.Error(w, "invalid path", http.StatusNotFound)
+		return
+	}
+	content, ok := fileContentMap.Load(r.URL.Path)
+	if !ok {
+		http.Error(w, "404 not found", http.StatusNotFound)
+		return
+	}
+	w.Write(content)
+}

internal/api/v1/file.go

@@ -0,0 +1,59 @@
+package v1
+
+import (
+	"io"
+	"net/http"
+	"os"
+	"path"
+
+	U "github.com/yusing/go-proxy/internal/api/v1/utils"
+	"github.com/yusing/go-proxy/internal/common"
+	"github.com/yusing/go-proxy/internal/config"
+	E "github.com/yusing/go-proxy/internal/error"
+	"github.com/yusing/go-proxy/internal/proxy/provider"
+)
+
+func GetFileContent(w http.ResponseWriter, r *http.Request) {
+	filename := r.PathValue("filename")
+	if filename == "" {
+		filename = common.ConfigFileName
+	}
+	content, err := os.ReadFile(path.Join(common.ConfigBasePath, filename))
+	if err != nil {
+		U.HandleErr(w, r, err)
+		return
+	}
+	w.Write(content)
+}
+
+func SetFileContent(w http.ResponseWriter, r *http.Request) {
+	filename := r.PathValue("filename")
+	if filename == "" {
+		U.HandleErr(w, r, U.ErrMissingKey("filename"), http.StatusBadRequest)
+		return
+	}
+	content, err := io.ReadAll(r.Body)
+	if err != nil {
+		U.HandleErr(w, r, err)
+		return
+	}
+
+	var validateErr E.NestedError
+	if filename == common.ConfigFileName {
+		validateErr = config.Validate(content)
+	} else {
+		validateErr = provider.Validate(content)
+	}
+
+	if validateErr != nil {
+		U.RespondJson(w, validateErr.JSONObject(), http.StatusBadRequest)
+		return
+	}
+
+	err = os.WriteFile(path.Join(common.ConfigBasePath, filename), content, 0644)
+	if err != nil {
+		U.HandleErr(w, r, err)
+		return
+	}
+	w.WriteHeader(http.StatusOK)
+}

internal/api/v1/index.go

@@ -0,0 +1,7 @@
+package v1
+
+import "net/http"
+
+func Index(w http.ResponseWriter, r *http.Request) {
+	w.Write([]byte("API ready"))
+}

internal/api/v1/list.go

@@ -0,0 +1,61 @@
+package v1
+
+import (
+	"encoding/json"
+	"net/http"
+	"os"
+
+	U "github.com/yusing/go-proxy/internal/api/v1/utils"
+	"github.com/yusing/go-proxy/internal/common"
+	"github.com/yusing/go-proxy/internal/config"
+)
+
+func List(cfg *config.Config, w http.ResponseWriter, r *http.Request) {
+	what := r.PathValue("what")
+	if what == "" {
+		what = "routes"
+	}
+
+	switch what {
+	case "routes":
+		listRoutes(cfg, w, r)
+	case "config_files":
+		listConfigFiles(w, r)
+	default:
+		U.HandleErr(w, r, U.ErrInvalidKey("what"), http.StatusBadRequest)
+	}
+}
+
+func listRoutes(cfg *config.Config, w http.ResponseWriter, r *http.Request) {
+	routes := cfg.RoutesByAlias()
+	typeFilter := r.FormValue("type")
+	if typeFilter != "" {
+		for k, v := range routes {
+			if v["type"] != typeFilter {
+				delete(routes, k)
+			}
+		}
+	}
+
+	if err := U.RespondJson(w, routes); err != nil {
+		U.HandleErr(w, r, err)
+	}
+}
+
+func listConfigFiles(w http.ResponseWriter, r *http.Request) {
+	files, err := os.ReadDir(common.ConfigBasePath)
+	if err != nil {
+		U.HandleErr(w, r, err)
+		return
+	}
+	filenames := make([]string, len(files))
+	for i, f := range files {
+		filenames[i] = f.Name()
+	}
+	resp, err := json.Marshal(filenames)
+	if err != nil {
+		U.HandleErr(w, r, err)
+		return
+	}
+	w.Write(resp)
+}

internal/api/v1/reload.go

@@ -0,0 +1,16 @@
+package v1
+
+import (
+	"net/http"
+
+	U "github.com/yusing/go-proxy/internal/api/v1/utils"
+	"github.com/yusing/go-proxy/internal/config"
+)
+
+func Reload(cfg *config.Config, w http.ResponseWriter, r *http.Request) {
+	if err := cfg.Reload(); err != nil {
+		U.RespondJson(w, err.JSONObject(), http.StatusInternalServerError)
+	} else {
+		w.WriteHeader(http.StatusOK)
+	}
+}

internal/api/v1/stats.go

@@ -0,0 +1,20 @@
+package v1
+
+import (
+	"net/http"
+
+	U "github.com/yusing/go-proxy/internal/api/v1/utils"
+	"github.com/yusing/go-proxy/internal/config"
+	"github.com/yusing/go-proxy/internal/server"
+	"github.com/yusing/go-proxy/internal/utils"
+)
+
+func Stats(cfg *config.Config, w http.ResponseWriter, r *http.Request) {
+	stats := map[string]any{
+		"proxies": cfg.Statistics(),
+		"uptime":  utils.FormatDuration(server.GetProxyServer().Uptime()),
+	}
+	if err := U.RespondJson(w, stats); err != nil {
+		U.HandleErr(w, r, err)
+	}
+}

internal/api/v1/utils/error.go

@@ -0,0 +1,34 @@
+package utils
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+
+	"github.com/sirupsen/logrus"
+	E "github.com/yusing/go-proxy/internal/error"
+)
+
+var Logger = logrus.WithField("module", "api")
+
+func HandleErr(w http.ResponseWriter, r *http.Request, origErr error, code ...int) {
+	err := E.From(origErr).Subjectf("%s %s", r.Method, r.URL)
+	Logger.Error(err)
+	if len(code) > 0 {
+		http.Error(w, err.String(), code[0])
+		return
+	}
+	http.Error(w, err.String(), http.StatusInternalServerError)
+}
+
+func ErrMissingKey(k string) error {
+	return errors.New("missing key '" + k + "' in query or request body")
+}
+
+func ErrInvalidKey(k string) error {
+	return errors.New("invalid key '" + k + "' in query or request body")
+}
+
+func ErrNotFound(k, v string) error {
+	return fmt.Errorf("key %q with value %q not found", k, v)
+}

internal/api/v1/utils/health_check.go

@@ -0,0 +1,33 @@
+package utils
+
+import (
+	"net"
+	"net/http"
+
+	"github.com/yusing/go-proxy/internal/common"
+)
+
+func IsSiteHealthy(url string) bool {
+	// try HEAD first
+	// if HEAD is not allowed, try GET
+	resp, err := httpClient.Head(url)
+	if resp != nil {
+		resp.Body.Close()
+	}
+	if err != nil && resp != nil && resp.StatusCode == http.StatusMethodNotAllowed {
+		_, err = httpClient.Get(url)
+	}
+	if resp != nil {
+		resp.Body.Close()
+	}
+	return err == nil
+}
+
+func IsStreamHealthy(scheme, address string) bool {
+	conn, err := net.DialTimeout(scheme, address, common.DialTimeout)
+	if err != nil {
+		return false
+	}
+	conn.Close()
+	return true
+}

internal/api/v1/utils/http_client.go

@@ -0,0 +1,23 @@
+package utils
+
+import (
+	"crypto/tls"
+	"net"
+	"net/http"
+
+	"github.com/yusing/go-proxy/internal/common"
+)
+
+var httpClient = &http.Client{
+	Timeout: common.ConnectionTimeout,
+	Transport: &http.Transport{
+		Proxy:             http.ProxyFromEnvironment,
+		DisableKeepAlives: true,
+		ForceAttemptHTTP2: true,
+		DialContext: (&net.Dialer{
+			Timeout:   common.DialTimeout,
+			KeepAlive: common.KeepAlive, // this is different from DisableKeepAlives
+		}).DialContext,
+		TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
+	},
+}

internal/api/v1/utils/localhost.go

@@ -0,0 +1,31 @@
+package utils
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+
+	"github.com/yusing/go-proxy/internal/common"
+	E "github.com/yusing/go-proxy/internal/error"
+)
+
+func ReloadServer() E.NestedError {
+	resp, err := httpClient.Post(fmt.Sprintf("%s/v1/reload", common.APIHTTPURL), "", nil)
+	if err != nil {
+		return E.From(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		failure := E.Failure("server reload").Extraf("status code: %v", resp.StatusCode)
+		b, err := io.ReadAll(resp.Body)
+		if err != nil {
+			return failure.Extraf("unable to read response body: %s", err)
+		}
+		reloadErr, ok := E.FromJSON(b)
+		if ok {
+			return E.Join("reload success, but server returned error", reloadErr)
+		}
+		return failure.Extraf("unable to read response body")
+	}
+	return nil
+}

internal/api/v1/utils/utils.go

@@ -0,0 +1,20 @@
+package utils
+
+import (
+	"encoding/json"
+	"net/http"
+)
+
+func RespondJson(w http.ResponseWriter, data any, code ...int) error {
+	if len(code) > 0 {
+		w.WriteHeader(code[0])
+	}
+	w.Header().Set("Content-Type", "application/json")
+	j, err := json.MarshalIndent(data, "", "  ")
+	if err != nil {
+		return err
+	} else {
+		w.Write(j)
+	}
+	return nil
+}