Add support for serving files when API doesn't return good result.

lib/web.go

@@ -9,17 +9,21 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"mime"
 	"net/http"
 	"net/url"
-	"strings"
-	"mime"
+	"os"
+	"path"
 	"path/filepath"
+	"strings"
 )
 
 type Forgejo struct {
-	Server url.URL
-	Token  string
-	Branch string
+	Server   url.URL
+	Token    string
+	Branch   string
+	NotFound string
+	Files    string
 }
 
 var ErrNotFound = errors.New("404 not found")
@@ -27,7 +31,14 @@ var ErrNotFound = errors.New("404 not found")
 // headers must ot be nil
 func (f *Forgejo) GetFile(ctx context.Context, headers map[string]string, user, repo, branch, file string) (ret *http.Response, err error) {
 	u := f.Server
-	u.Path = "/api/v1/repos/" + user + "/" + repo + "/raw/" + file
+	u.Path = path.Join(
+		u.Path,
+		"api/v1/repos",
+		user,
+		repo,
+		"raw",
+		file,
+	)
 	p := u.Query()
 	p.Set("ref", branch)
 	u.RawQuery = p.Encode()
@@ -36,7 +47,7 @@ func (f *Forgejo) GetFile(ctx context.Context, headers map[string]string, user,
 	if err != nil {
 		return
 	}
-	
+
 	for k, v := range headers {
 		if v == "" {
 			continue
@@ -46,13 +57,13 @@ func (f *Forgejo) GetFile(ctx context.Context, headers map[string]string, user,
 	req.Header.Set("Authorization", "token "+f.Token)
 	resp, err := http.DefaultClient.Do(req)
 	if err != nil {
-		return
+		return nil, err
 	}
 	if resp.StatusCode == http.StatusNotFound {
-		err = ErrNotFound
-		return
+		resp.Body.Close()
+		return nil, ErrNotFound
 	}
-	
+
 	return resp, nil
 }
 
@@ -87,12 +98,49 @@ func trySet(h http.Header, key string, src http.Header) {
 	h.Set(key, value)
 }
 
+func (f *Forgejo) serveLocalFile(w http.ResponseWriter, r *http.Request, status int) {
+	path := strings.TrimPrefix(r.URL.Path, "/")
+	if path == "" {
+		path = "index.html"
+	}
+
+	if f.Files != "" {
+		path = filepath.Join(f.Files, path)
+	}
+
+	fmt.Println("Serving local file:", path)
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		path := f.NotFound
+
+		data, readErr := os.ReadFile(path)
+		if readErr != nil {
+			http.Error(w, "404 not found", http.StatusNotFound)
+			return
+		}
+
+		w.Header().Set("Content-Type", "text/html; charset=utf-8")
+		w.WriteHeader(http.StatusNotFound)
+		w.Write(data)
+		return
+	}
+
+	if ct := mime.TypeByExtension(filepath.Ext(path)); ct != "" {
+		w.Header().Set("Content-Type", ct)
+	}
+
+	w.WriteHeader(status)
+	w.Write(data)
+}
+
 func (f *Forgejo) handle(w http.ResponseWriter, r *http.Request) {
 	arr := strings.Split(r.URL.Path[1:], "/")
 	if len(arr) < 2 {
-		w.WriteHeader(http.StatusBadRequest)
+		f.serveLocalFile(w, r, http.StatusOK)
 		return
 	}
+
 	user, repo := arr[0], arr[1]
 	if user == "u" {
 		user, repo = repo, f.Branch
@@ -104,7 +152,7 @@ func (f *Forgejo) handle(w http.ResponseWriter, r *http.Request) {
 		}
 		file = strings.Join(arr[2:], "/")
 	}
-	
+
 	headers := map[string]string{}
 	headers["If-None-Match"] = r.Header.Get("If-None-Match")
 	headers["If-Modified-Since"] = r.Header.Get("If-Modified-Since")
@@ -122,11 +170,16 @@ func (f *Forgejo) handle(w http.ResponseWriter, r *http.Request) {
 	headers["CF-Ray"] = r.Header.Get("CF-Ray")
 	resp, err := f.GetFile(r.Context(), headers, user, repo, f.Branch, file)
 	if err != nil {
+		if errors.Is(err, ErrNotFound) {
+			f.serveLocalFile(w, r, http.StatusNotFound)
+			return
+		}
+
 		w.WriteHeader(http.StatusNotFound)
 		return
 	}
 	defer resp.Body.Close()
-	
+
 	trySet(w.Header(), "Etag", resp.Header)
 	trySet(w.Header(), "Last-Modified", resp.Header)
 	trySet(w.Header(), "Content-Length", resp.Header)
@@ -140,7 +193,7 @@ func (f *Forgejo) handle(w http.ResponseWriter, r *http.Request) {
 	if contentType != "" {
 		w.Header().Set("Content-Type", contentType)
 	}
-	
+
 	w.WriteHeader(resp.StatusCode)
 	io.Copy(w, resp.Body)
 }