rclone/cmd/serve/http/http.go

254 lines
6.1 KiB
Go

package http
import (
"fmt"
"html/template"
"net/http"
"os"
"path"
"strconv"
"strings"
"github.com/ncw/rclone/cmd"
"github.com/ncw/rclone/cmd/serve/httplib"
"github.com/ncw/rclone/fs"
"github.com/ncw/rclone/fs/accounting"
"github.com/ncw/rclone/lib/rest"
"github.com/ncw/rclone/vfs"
"github.com/ncw/rclone/vfs/vfsflags"
"github.com/spf13/cobra"
)
func init() {
httplib.AddFlags(Command.Flags())
vfsflags.AddFlags(Command.Flags())
}
// Command definition for cobra
var Command = &cobra.Command{
Use: "http remote:path",
Short: `Serve the remote over HTTP.`,
Long: `rclone serve http implements a basic web server to serve the remote
over HTTP. This can be viewed in a web browser or you can make a
remote of type http read from it.
You can use the filter flags (eg --include, --exclude) to control what
is served.
The server will log errors. Use -v to see access logs.
--bwlimit will be respected for file transfers. Use --stats to
control the stats printing.
` + httplib.Help + vfs.Help,
Run: func(command *cobra.Command, args []string) {
cmd.CheckArgs(1, 1, command, args)
f := cmd.NewFsSrc(args)
cmd.Run(false, true, command, func() error {
s := newServer(f)
s.serve()
return nil
})
},
}
// server contains everything to run the server
type server struct {
f fs.Fs
vfs *vfs.VFS
srv *httplib.Server
}
func newServer(f fs.Fs) *server {
mux := http.NewServeMux()
s := &server{
f: f,
vfs: vfs.New(f, &vfsflags.Opt),
srv: httplib.NewServer(mux),
}
mux.HandleFunc("/", s.handler)
return s
}
// serve runs the http server - doesn't return
func (s *server) serve() {
fs.Logf(s.f, "Serving on %s", s.srv.URL())
s.srv.Serve()
}
// handler reads incoming requests and dispatches them
func (s *server) handler(w http.ResponseWriter, r *http.Request) {
if r.Method != "GET" && r.Method != "HEAD" {
http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
return
}
w.Header().Set("Accept-Ranges", "bytes")
w.Header().Set("Server", "rclone/"+fs.Version)
urlPath := r.URL.Path
isDir := strings.HasSuffix(urlPath, "/")
remote := strings.Trim(urlPath, "/")
if isDir {
s.serveDir(w, r, remote)
} else {
s.serveFile(w, r, remote)
}
}
// entry is a directory entry
type entry struct {
remote string
URL string
Leaf string
}
// entries represents a directory
type entries []entry
// addEntry adds an entry to that directory
func (es *entries) addEntry(node interface {
Path() string
Name() string
IsDir() bool
}) {
remote := node.Path()
leaf := node.Name()
urlRemote := leaf
if node.IsDir() {
leaf += "/"
urlRemote += "/"
}
*es = append(*es, entry{remote: remote, URL: rest.URLPathEscape(urlRemote), Leaf: leaf})
}
// indexPage is a directory listing template
var indexPage = `<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>{{ .Title }}</title>
</head>
<body>
<h1>{{ .Title }}</h1>
{{ range $i := .Entries }}<a href="{{ $i.URL }}">{{ $i.Leaf }}</a><br />
{{ end }}</body>
</html>
`
// indexTemplate is the instantiated indexPage
var indexTemplate = template.Must(template.New("index").Parse(indexPage))
// indexData is used to fill in the indexTemplate
type indexData struct {
Title string
Entries entries
}
// error returns an http.StatusInternalServerError and logs the error
func internalError(what interface{}, w http.ResponseWriter, text string, err error) {
fs.CountError(err)
fs.Errorf(what, "%s: %v", text, err)
http.Error(w, text+".", http.StatusInternalServerError)
}
// serveDir serves a directory index at dirRemote
func (s *server) serveDir(w http.ResponseWriter, r *http.Request, dirRemote string) {
// List the directory
node, err := s.vfs.Stat(dirRemote)
if err == vfs.ENOENT {
http.Error(w, "Directory not found", http.StatusNotFound)
return
} else if err != nil {
internalError(dirRemote, w, "Failed to list directory", err)
return
}
if !node.IsDir() {
http.Error(w, "Not a directory", http.StatusNotFound)
return
}
dir := node.(*vfs.Dir)
dirEntries, err := dir.ReadDirAll()
if err != nil {
internalError(dirRemote, w, "Failed to list directory", err)
return
}
var out entries
for _, node := range dirEntries {
out.addEntry(node)
}
// Account the transfer
accounting.Stats.Transferring(dirRemote)
defer accounting.Stats.DoneTransferring(dirRemote, true)
fs.Infof(dirRemote, "%s: Serving directory", r.RemoteAddr)
err = indexTemplate.Execute(w, indexData{
Entries: out,
Title: fmt.Sprintf("Directory listing of /%s", dirRemote),
})
if err != nil {
internalError(dirRemote, w, "Failed to render template", err)
return
}
}
// serveFile serves a file object at remote
func (s *server) serveFile(w http.ResponseWriter, r *http.Request, remote string) {
node, err := s.vfs.Stat(remote)
if err == vfs.ENOENT {
fs.Infof(remote, "%s: File not found", r.RemoteAddr)
http.Error(w, "File not found", http.StatusNotFound)
return
} else if err != nil {
internalError(remote, w, "Failed to find file", err)
return
}
if !node.IsFile() {
http.Error(w, "Not a file", http.StatusNotFound)
return
}
entry := node.DirEntry()
if entry == nil {
http.Error(w, "Can't open file being written", http.StatusNotFound)
return
}
obj := entry.(fs.Object)
file := node.(*vfs.File)
// Set content length since we know how long the object is
w.Header().Set("Content-Length", strconv.FormatInt(node.Size(), 10))
// Set content type
mimeType := fs.MimeType(obj)
if mimeType == "application/octet-stream" && path.Ext(remote) == "" {
// Leave header blank so http server guesses
} else {
w.Header().Set("Content-Type", mimeType)
}
// If HEAD no need to read the object since we have set the headers
if r.Method == "HEAD" {
return
}
// open the object
in, err := file.Open(os.O_RDONLY)
if err != nil {
internalError(remote, w, "Failed to open file", err)
return
}
defer func() {
err := in.Close()
if err != nil {
fs.Errorf(remote, "Failed to close file: %v", err)
}
}()
// Account the transfer
accounting.Stats.Transferring(remote)
defer accounting.Stats.DoneTransferring(remote, true)
// FIXME in = fs.NewAccount(in, obj).WithBuffer() // account the transfer
// Serve the file
http.ServeContent(w, r, remote, node.ModTime(), in)
}