woodpecker/server/web/web.go
2023-08-07 17:03:26 +02:00

179 lines
5.1 KiB
Go

// Copyright 2018 Drone.IO Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package web
import (
"bytes"
"crypto/md5"
"errors"
"fmt"
"io"
"io/fs"
"net/http"
"strings"
"time"
"github.com/gin-gonic/gin"
"github.com/rs/zerolog/log"
"github.com/woodpecker-ci/woodpecker/server"
"github.com/woodpecker-ci/woodpecker/web"
)
// etag is an identifier for a resource version
// it lets caches determine if resource is still the same and not send it again
var (
etag = fmt.Sprintf("%x", md5.Sum([]byte(time.Now().String())))
indexHTML []byte
)
type prefixFS struct {
fs http.FileSystem
prefix string
}
func (f *prefixFS) Open(name string) (http.File, error) {
return f.fs.Open(strings.TrimPrefix(name, f.prefix))
}
// New returns a gin engine to serve the web frontend.
func New() (*gin.Engine, error) {
e := gin.New()
indexHTML = parseIndex()
e.Use(setupCache)
rootPath := server.Config.Server.RootPath
httpFS, err := web.HTTPFS()
if err != nil {
return nil, err
}
f := &prefixFS{httpFS, rootPath}
e.GET(rootPath+"/favicon.svg", redirect(server.Config.Server.RootPath+"/favicons/favicon-light-default.svg", http.StatusPermanentRedirect))
e.GET(rootPath+"/favicons/*filepath", serveFile(f))
e.GET(rootPath+"/assets/*filepath", handleCustomFilesAndAssets(f))
e.NoRoute(handleIndex)
return e, nil
}
func handleCustomFilesAndAssets(fs *prefixFS) func(ctx *gin.Context) {
serveFileOrEmptyContent := func(w http.ResponseWriter, r *http.Request, localFileName string) {
if len(localFileName) > 0 {
http.ServeFile(w, r, localFileName)
} else {
// prefer zero content over sending a 404 Not Found
http.ServeContent(w, r, localFileName, time.Now(), bytes.NewReader([]byte{}))
}
}
return func(ctx *gin.Context) {
if strings.HasSuffix(ctx.Request.RequestURI, "/assets/custom.js") {
serveFileOrEmptyContent(ctx.Writer, ctx.Request, server.Config.Server.CustomJsFile)
} else if strings.HasSuffix(ctx.Request.RequestURI, "/assets/custom.css") {
serveFileOrEmptyContent(ctx.Writer, ctx.Request, server.Config.Server.CustomCSSFile)
} else {
serveFile(fs)(ctx)
}
}
}
func serveFile(f *prefixFS) func(ctx *gin.Context) {
return func(ctx *gin.Context) {
file, err := f.Open(ctx.Request.URL.Path)
if err != nil {
code := http.StatusInternalServerError
if errors.Is(err, fs.ErrNotExist) {
code = http.StatusNotFound
} else if errors.Is(err, fs.ErrPermission) {
code = http.StatusForbidden
}
ctx.Status(code)
return
}
data, err := io.ReadAll(file)
if err != nil {
ctx.Status(http.StatusInternalServerError)
return
}
var mime string
switch {
case strings.HasSuffix(ctx.Request.URL.Path, ".js"):
mime = "text/javascript"
case strings.HasSuffix(ctx.Request.URL.Path, ".css"):
mime = "text/css"
case strings.HasSuffix(ctx.Request.URL.Path, ".png"):
mime = "image/png"
case strings.HasSuffix(ctx.Request.URL.Path, ".svg"):
mime = "image/svg"
}
ctx.Status(http.StatusOK)
ctx.Writer.Header().Set("Content-Type", mime)
if _, err := ctx.Writer.Write(replaceBytes(data)); err != nil {
log.Error().Err(err).Msgf("can not write %s", ctx.Request.URL.Path)
}
}
}
// redirect return gin helper to redirect a request
func redirect(location string, status ...int) func(ctx *gin.Context) {
return func(ctx *gin.Context) {
code := http.StatusFound
if len(status) == 1 {
code = status[0]
}
http.Redirect(ctx.Writer, ctx.Request, location, code)
}
}
func handleIndex(c *gin.Context) {
rw := c.Writer
rw.Header().Set("Content-Type", "text/html; charset=UTF-8")
rw.WriteHeader(http.StatusOK)
if _, err := rw.Write(indexHTML); err != nil {
log.Error().Err(err).Msg("can not write index.html")
}
}
func loadFile(path string) ([]byte, error) {
data, err := web.Lookup(path)
if err != nil {
return nil, err
}
return replaceBytes(data), nil
}
func replaceBytes(data []byte) []byte {
return bytes.ReplaceAll(data, []byte("/BASE_PATH"), []byte(server.Config.Server.RootPath))
}
func parseIndex() []byte {
data, err := loadFile("index.html")
if err != nil {
log.Fatal().Err(err).Msg("can not find index.html")
}
data = bytes.ReplaceAll(data, []byte("/web-config.js"), []byte(server.Config.Server.RootPath+"/web-config.js"))
data = bytes.ReplaceAll(data, []byte("/assets/custom.css"), []byte(server.Config.Server.RootPath+"/assets/custom.css"))
data = bytes.ReplaceAll(data, []byte("/assets/custom.js"), []byte(server.Config.Server.RootPath+"/assets/custom.js"))
return data
}
func setupCache(c *gin.Context) {
c.Writer.Header().Set("Cache-Control", "public, max-age=31536000")
c.Writer.Header().Del("Expires")
c.Writer.Header().Set("ETag", etag)
}