Moving dir2opds from opds repo

README.md

@@ -1,2 +1,16 @@
 # dir2opds
 Serve an OPDS server based on a directory
+
+Some times you only have a directory with books and you want an OPDS, but to get from dir to OPDS you maybe need to do some work, this project aim to
+simplely works.
+
+It didn't pass the opds validator yet. But the plan is to get to that point.
+
+# Installation
+
+go get github.com/dubyte/dir2opds
+
+#usage
+
+dir2opds -dir ./books -port 8080
+

main.go

@@ -0,0 +1,157 @@
+/*
+  Copyright (C) 2017 Sinuhé Téllez Rivera
+
+  dir2opds is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  dir2opds is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with dir2opds.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package main
+
+import (
+	"encoding/xml"
+	"encoding/base64"
+	"flag"
+	"io"
+	"io/ioutil"
+	"log"
+	"mime"
+	"net/http"
+	"os"
+	"path"
+	"path/filepath"
+
+	"golang.org/x/tools/blog/atom"
+)
+
+var dirRoot string
+
+func init() {
+	mime.AddExtensionType(".mobi", "application/x-mobipocket-ebook")
+	mime.AddExtensionType(".epub", "application/epub+zip")
+	mime.AddExtensionType(".fb2", "txt/xml")
+	http.HandleFunc("/", errorHandler(catalogRoot))
+}
+
+func main() {
+	portPtr := flag.String("port", "8080", "The server will listen in this port")
+	dirPtr := flag.String("dir", "./books", "A directory with books")
+	flag.Parse()
+
+	dirRoot = *dirPtr
+	log.Fatal(http.ListenAndServe(":"+*portPtr, nil))
+}
+
+func errorHandler(f func(http.ResponseWriter, *http.Request) error) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		err := f(w, r)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			log.Printf("handling %q: %v", r.RequestURI, err)
+		}
+	}
+}
+
+func catalogRoot(w http.ResponseWriter, req *http.Request) error {
+	dirPath := filepath.Join(dirRoot, req.URL.Path)
+	fi, err := os.Stat(dirPath)
+	if err != nil {
+		return err
+	}
+
+	if fi.IsDir() {
+		return catalogFeed(w, req, dirPath)
+	}
+	return writeFileTo(w, dirPath)
+}
+
+func catalogFeed(w io.Writer, r *http.Request, dirPath string) error {
+	fis, err := ioutil.ReadDir(dirPath)
+	if err != nil {
+		return err
+	}
+	feed := &atom.Feed{Title: "OPDS Catalog: " + r.URL.Path}
+	if len(fis) < 1 {
+		return writeFeedTo(w, feed)
+	}
+
+	err = FeedEntries(feed, fis, r)
+	if err != nil {
+		return err
+	}
+
+	return writeFeedTo(w, feed)
+}
+
+func FeedEntries(f *atom.Feed, fis []os.FileInfo, r *http.Request) error {
+	for _, fi := range fis {
+		e := &atom.Entry{Title: fi.Name()}
+		encoded := base64.StdEncoding.EncodeToString([]byte(path.Join(r.URL.Path, fi.Name())))
+		e.ID = encoded
+		l := atom.Link{Title: fi.Name(), Href: path.Join(r.URL.EscapedPath(), fi.Name())}
+		if !fi.IsDir() {
+			l.Rel = "http://opds-spec.org/acquisition"
+		}
+		lType, err := getLinkType(path.Join(dirRoot, r.URL.Path, fi.Name()))
+		if err != nil {
+			return err
+		}
+		l.Type = lType
+		e.Link = append(e.Link, l)
+		f.Entry = append(f.Entry, e)
+	}
+	return nil
+}
+
+func writeFeedTo(w io.Writer, feed *atom.Feed) error {
+	io.WriteString(w, "<?xml version=\"1.0\" encoding=\"UTF-8\"?>")
+	enc := xml.NewEncoder(w)
+	enc.Indent("  ", "    ")
+	if err := enc.Encode(feed); err != nil {
+		return err
+	}
+	return nil
+}
+
+func writeFileTo(w io.Writer, filepath string) error {
+	f, err := os.Open(filepath)
+	if err != nil {
+		return err
+	}
+	_, err = io.Copy(w, f)
+	if err != nil {
+		f.Close()
+		return err
+	}
+	f.Close()
+	return nil
+}
+
+func getLinkType(lPath string) (string, error) {
+	fi, err := os.Stat(lPath)
+	if err != nil {
+		return "", err
+	}
+	if !fi.IsDir() {
+		return mime.TypeByExtension(filepath.Ext(lPath)), nil
+	}
+	files, err := ioutil.ReadDir(lPath)
+	if err != nil {
+		return "", err
+	}
+	for _, file := range files {
+		if !file.IsDir() {
+			return "application/atom+xml;profile=opds-catalog;kind=acquisition", nil
+		}
+	}
+	return "application/atom+xml;profile=opds-catalog;kind=navigation", nil
+}