feat: set up configuration

A YAML file is used to set the available feeds.
The CLI args can set the port and the path to the YAML file.

config.yml

@@ -0,0 +1,5 @@
+feeds:
+  - name: "Evan's Library"
+    url: "http://calibre.terminus/opds"
+  - name: "Project Gutenberg"
+    url: "http://gutenberg.org/opds"

go.mod

@@ -1,3 +1,20 @@
 module github.com/evan-buss/opds-proxy
 
 go 1.22
+
+require (
+	github.com/knadh/koanf/parsers/yaml v0.1.0
+	github.com/knadh/koanf/providers/file v1.0.0
+	github.com/knadh/koanf/v2 v2.1.1
+)
+
+require (
+	github.com/fsnotify/fsnotify v1.7.0 // indirect
+	github.com/go-viper/mapstructure/v2 v2.0.0 // indirect
+	github.com/knadh/koanf/maps v0.1.1 // indirect
+	github.com/knadh/koanf/providers/basicflag v1.0.0
+	github.com/mitchellh/copystructure v1.2.0 // indirect
+	github.com/mitchellh/reflectwalk v1.0.2 // indirect
+	golang.org/x/sys v0.22.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

@@ -0,0 +1,30 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/fsnotify/fsnotify v1.7.0 h1:8JEhPFa5W2WU7YfeZzPNqzMP6Lwt7L2715Ggo0nosvA=
+github.com/fsnotify/fsnotify v1.7.0/go.mod h1:40Bi/Hjc2AVfZrqy+aj+yEI+/bRxZnMJyTJwOpGvigM=
+github.com/go-viper/mapstructure/v2 v2.0.0 h1:dhn8MZ1gZ0mzeodTG3jt5Vj/o87xZKuNAprG2mQfMfc=
+github.com/go-viper/mapstructure/v2 v2.0.0/go.mod h1:oJDH3BJKyqBA2TXFhDsKDGDTlndYOZ6rGS0BRZIxGhM=
+github.com/knadh/koanf/maps v0.1.1 h1:G5TjmUh2D7G2YWf5SQQqSiHRJEjaicvU0KpypqB3NIs=
+github.com/knadh/koanf/maps v0.1.1/go.mod h1:npD/QZY3V6ghQDdcQzl1W4ICNVTkohC8E73eI2xW4yI=
+github.com/knadh/koanf/parsers/yaml v0.1.0 h1:ZZ8/iGfRLvKSaMEECEBPM1HQslrZADk8fP1XFUxVI5w=
+github.com/knadh/koanf/parsers/yaml v0.1.0/go.mod h1:cvbUDC7AL23pImuQP0oRw/hPuccrNBS2bps8asS0CwY=
+github.com/knadh/koanf/providers/basicflag v1.0.0 h1:qB0es/9fYsLuYnrKazxNCuWtkv3JFX1lI1druUsDDvY=
+github.com/knadh/koanf/providers/basicflag v1.0.0/go.mod h1:n0NlnaxXUCER/WIzRroT9q3Np+FiZ9pSjrC6A/OozI8=
+github.com/knadh/koanf/providers/file v1.0.0 h1:DtPvSQBeF+N0QLPMz0yf2bx0nFSxUcncpqQvzCxfCyk=
+github.com/knadh/koanf/providers/file v1.0.0/go.mod h1:/faSBcv2mxPVjFrXck95qeoyoZ5myJ6uxN8OOVNJJCI=
+github.com/knadh/koanf/v2 v2.1.1 h1:/R8eXqasSTsmDCsAyYj+81Wteg8AqrV9CP6gvsTsOmM=
+github.com/knadh/koanf/v2 v2.1.1/go.mod h1:4mnTRbZCK+ALuBXHZMjDfG9y714L7TykVnZkXbMU3Es=
+github.com/mitchellh/copystructure v1.2.0 h1:vpKXTN4ewci03Vljg/q9QvCGUDttBOGBIa15WveJJGw=
+github.com/mitchellh/copystructure v1.2.0/go.mod h1:qLl+cE2AmVv+CoeAwDPye/v+N2HKCj9FbZEVFJRxO9s=
+github.com/mitchellh/reflectwalk v1.0.2 h1:G2LzWKi524PWgd3mLHV8Y5k7s6XUvT0Gef6zxSIeXaQ=
+github.com/mitchellh/reflectwalk v1.0.2/go.mod h1:mSTlrgnPZtwu0c4WaC2kGObEpuNDbx0jmZXqmk4esnw=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
+github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+golang.org/x/sys v0.22.0 h1:RI27ohtqKCnwULzJLqkv897zojh5/DwS/ENaMzUOaWI=
+golang.org/x/sys v0.22.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

main.go

@@ -1,221 +1,54 @@
 package main
 
 import (
-	"fmt"
+	"flag"
-	"io"
 	"log"
-	"log/slog"
-	"mime"
-	"net/http"
-	"net/url"
 	"os"
-	"path/filepath"
-	"strings"
-	"time"
 
-	"github.com/evan-buss/opds-proxy/convert"
+	"github.com/knadh/koanf/parsers/yaml"
-	"github.com/evan-buss/opds-proxy/html"
+	"github.com/knadh/koanf/providers/basicflag"
-	"github.com/evan-buss/opds-proxy/opds"
+	"github.com/knadh/koanf/providers/file"
+	"github.com/knadh/koanf/v2"
 )
 
+type config struct {
+	Port  string       `koanf:"port"`
+	Feeds []feedConfig `koanf:"feeds" `
+}
+
+type feedConfig struct {
+	Name string `koanf:"name"`
+	Url  string `koanf:"url"`
+}
+
+var k = koanf.New(".")
+
 func main() {
-	server := NewServer()
+	fs := flag.NewFlagSet("", flag.ContinueOnError)
-
+	fs.String("port", "8080", "port to listen on")
-	slog.Info("Starting server", slog.String("port", server.addr))
+	configPath := fs.String("config", "config.yml", "config file to load")
-	log.Fatal(http.ListenAndServe(server.addr, server.router))
+	if err := fs.Parse(os.Args[1:]); err != nil {
+		os.Exit(0)
 	}
 
-func handleHome() http.HandlerFunc {
+	// Load config file from disk.
-	return func(w http.ResponseWriter, r *http.Request) {
+	// Feed options must be defined here.
-		slog.Info("Rendering home page")
+	if err := k.Load(file.Provider(*configPath), yaml.Parser()); err != nil && !os.IsNotExist(err) {
-		feeds := []html.FeedInfo{
-			{
-				Title: "Evan's Library",
-				URL:   "http://calibre.terminus/opds",
-			},
-			{
-				Title: "Project Gutenberg",
-				URL:   "https://m.gutenberg.org/ebooks.opds/",
-			},
-		}
-		html.Home(w, feeds, partial(r))
-	}
-}
-
-func handleFeed(dir string) http.HandlerFunc {
-	kepubConverter := &convert.KepubConverter{}
-	mobiConverter := &convert.MobiConverter{}
-
-	return func(w http.ResponseWriter, r *http.Request) {
-		queryURL := r.URL.Query().Get("q")
-		if queryURL == "" {
-			http.Error(w, "No feed specified", http.StatusBadRequest)
-			return
-		}
-
-		parsedUrl, err := url.PathUnescape(queryURL)
-		queryURL = parsedUrl
-		if err != nil {
-			handleError(r, w, "Failed to parse URL", err)
-			return
-		}
-
-		searchTerm := r.URL.Query().Get("search")
-		if searchTerm != "" {
-			fmt.Println("Search term", searchTerm)
-			queryURL = replaceSearchPlaceHolder(queryURL, searchTerm)
-		}
-
-		resp, err := fetchFromUrl(queryURL)
-		if err != nil {
-			handleError(r, w, "Failed to fetch", err)
-			return
-		}
-		defer resp.Body.Close()
-
-		contentType := resp.Header.Get("Content-Type")
-		mimeType, _, err := mime.ParseMediaType(contentType)
-		if err != nil {
-			handleError(r, w, "Failed to parse content type", err)
-		}
-
-		if mimeType == "application/atom+xml" {
-			feed, err := opds.ParseFeed(resp.Body)
-			if err != nil {
-				handleError(r, w, "Failed to parse feed", err)
-				return
-			}
-
-			feedParams := html.FeedParams{
-				URL:  queryURL,
-				Feed: feed,
-			}
-
-			err = html.Feed(w, feedParams, partial(r))
-			if err != nil {
-				handleError(r, w, "Failed to render feed", err)
-				return
-			}
-		}
-
-		if mimeType != convert.EPUB_MIME {
-			for k, v := range resp.Header {
-				w.Header()[k] = v
-			}
-
-			io.Copy(w, resp.Body)
-			return
-		}
-
-		if strings.Contains(r.Header.Get("User-Agent"), "Kobo") && kepubConverter.Available() {
-			epubFile := filepath.Join(dir, parseFileName(resp))
-			downloadFile(epubFile, resp)
-
-			kepubFile := filepath.Join(dir, strings.Replace(parseFileName(resp), ".epub", ".kepub.epub", 1))
-			kepubConverter.Convert(epubFile, kepubFile)
-			if err != nil {
-				handleError(r, w, "Failed to convert to kepub", err)
-			}
-
-			outFile, _ := os.Open(kepubFile)
-			defer outFile.Close()
-
-			outInfo, _ := outFile.Stat()
-
-			w.Header().Set("Content-Length", fmt.Sprintf("%d", outInfo.Size()))
-			w.Header().Set("Content-Disposition", mime.FormatMediaType("attachment", map[string]string{"filename": filepath.Base(kepubFile)}))
-			w.Header().Set("Content-Type", convert.EPUB_MIME)
-
-			io.Copy(w, outFile)
-
-			os.Remove(epubFile)
-			os.Remove(kepubFile)
-
-			return
-		}
-
-		if strings.Contains(r.Header.Get("User-Agent"), "Kindle") && mobiConverter.Available() {
-			epubFile := filepath.Join(dir, parseFileName(resp))
-			downloadFile(epubFile, resp)
-
-			mobiFile := filepath.Join(dir, strings.Replace(parseFileName(resp), ".epub", ".mobi", 1))
-			err := mobiConverter.Convert(epubFile, mobiFile)
-			if err != nil {
-				handleError(r, w, "Failed to convert to mobi", err)
-				return
-			}
-
-			outFile, _ := os.Open(mobiFile)
-			defer outFile.Close()
-
-			outInfo, _ := outFile.Stat()
-
-			w.Header().Set("Content-Length", fmt.Sprintf("%d", outInfo.Size()))
-			w.Header().Set("Content-Disposition", mime.FormatMediaType("attachment", map[string]string{"filename": filepath.Base(mobiFile)}))
-			w.Header().Set("Content-Type", convert.MOBI_MIME)
-
-			io.Copy(w, outFile)
-
-			os.Remove(epubFile)
-			os.Remove(mobiFile)
-
-			return
-		}
-
-		for k, v := range resp.Header {
-			w.Header()[k] = v
-		}
-
-		io.Copy(w, resp.Body)
-	}
-}
-
-func fetchFromUrl(url string) (*http.Response, error) {
-	client := &http.Client{
-		Timeout: 2 * time.Second,
-	}
-
-	req, err := http.NewRequest("GET", url, nil)
-	if err != nil {
-		return nil, err
-	}
-	req.SetBasicAuth("public", "evanbuss")
-
-	return client.Do(req)
-}
-
-func handleError(r *http.Request, w http.ResponseWriter, message string, err error) {
-	slog.Error(message, slog.String("path", r.URL.RawPath), slog.Any("error", err))
-	http.Error(w, "An unexpected error occurred", http.StatusInternalServerError)
-}
-
-func replaceSearchPlaceHolder(url string, searchTerm string) string {
-	return strings.Replace(url, "{searchTerms}", searchTerm, 1)
-}
-
-func partial(req *http.Request) string {
-	return req.URL.Query().Get("partial")
-}
-
-func downloadFile(path string, resp *http.Response) {
-	file, err := os.Create(path)
-	if err != nil {
-		log.Fatal(err)
-	}
-	defer file.Close()
-
-	_, err = io.Copy(file, resp.Body)
-	if err != nil {
-		log.Fatal(err)
-	}
-}
-
-func parseFileName(resp *http.Response) string {
-	contentDisposition := resp.Header.Get("Content-Disposition")
-	_, params, err := mime.ParseMediaType(contentDisposition)
-	if err != nil {
 		log.Fatal(err)
 	}
 
-	return params["filename"]
+	// Flags take precedence over config file.
+	if err := k.Load(basicflag.Provider(fs, "."), nil); err != nil {
+		log.Fatal(err)
+	}
+
+	config := config{}
+	k.Unmarshal("", &config)
+
+	if len(config.Feeds) == 0 {
+		log.Fatal("No feeds defined in config")
+	}
+
+	server := NewServer(&config)
+	server.Serve()
 }

server.go

@@ -1,10 +1,21 @@
 package main
 
 import (
+	"fmt"
+	"io"
+	"log"
+	"log/slog"
+	"mime"
 	"net/http"
+	"net/url"
 	"os"
+	"path/filepath"
+	"strings"
+	"time"
 
+	"github.com/evan-buss/opds-proxy/convert"
 	"github.com/evan-buss/opds-proxy/html"
+	"github.com/evan-buss/opds-proxy/opds"
 )
 
 type Middleware func(http.HandlerFunc) http.HandlerFunc
@@ -14,19 +25,211 @@ type Server struct {
 	router *http.ServeMux
 }
 
-func NewServer() *Server {
+func NewServer(config *config) *Server {
-	port := os.Getenv("PORT")
-	if os.Getenv("PORT") == "" {
-		port = "8080"
-	}
-
 	router := http.NewServeMux()
-	router.HandleFunc("GET /{$}", handleHome())
+	router.HandleFunc("GET /{$}", handleHome(config.Feeds))
 	router.HandleFunc("GET /feed", handleFeed("tmp/"))
 	router.Handle("GET /static/", http.FileServer(http.FS(html.StaticFiles())))
 
 	return &Server{
-		addr:   ":" + port,
+		addr:   ":" + config.Port,
 		router: router,
 	}
 }
+
+func (s *Server) Serve() {
+	slog.Info("Starting server", slog.String("port", s.addr))
+	log.Fatal(http.ListenAndServe(s.addr, s.router))
+}
+
+func handleHome(feeds []feedConfig) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		vmFeeds := make([]html.FeedInfo, len(feeds))
+		for i, feed := range feeds {
+			vmFeeds[i] = html.FeedInfo{
+				Title: feed.Name,
+				URL:   feed.Url,
+			}
+		}
+
+		html.Home(w, vmFeeds, partial(r))
+	}
+}
+
+func handleFeed(dir string) http.HandlerFunc {
+	kepubConverter := &convert.KepubConverter{}
+	mobiConverter := &convert.MobiConverter{}
+
+	return func(w http.ResponseWriter, r *http.Request) {
+		queryURL := r.URL.Query().Get("q")
+		if queryURL == "" {
+			http.Error(w, "No feed specified", http.StatusBadRequest)
+			return
+		}
+
+		parsedUrl, err := url.PathUnescape(queryURL)
+		queryURL = parsedUrl
+		if err != nil {
+			handleError(r, w, "Failed to parse URL", err)
+			return
+		}
+
+		searchTerm := r.URL.Query().Get("search")
+		if searchTerm != "" {
+			fmt.Println("Search term", searchTerm)
+			queryURL = replaceSearchPlaceHolder(queryURL, searchTerm)
+		}
+
+		resp, err := fetchFromUrl(queryURL)
+		if err != nil {
+			handleError(r, w, "Failed to fetch", err)
+			return
+		}
+		defer resp.Body.Close()
+
+		contentType := resp.Header.Get("Content-Type")
+		mimeType, _, err := mime.ParseMediaType(contentType)
+		if err != nil {
+			handleError(r, w, "Failed to parse content type", err)
+		}
+
+		if mimeType == "application/atom+xml" {
+			feed, err := opds.ParseFeed(resp.Body)
+			if err != nil {
+				handleError(r, w, "Failed to parse feed", err)
+				return
+			}
+
+			feedParams := html.FeedParams{
+				URL:  queryURL,
+				Feed: feed,
+			}
+
+			err = html.Feed(w, feedParams, partial(r))
+			if err != nil {
+				handleError(r, w, "Failed to render feed", err)
+				return
+			}
+		}
+
+		if mimeType != convert.EPUB_MIME {
+			for k, v := range resp.Header {
+				w.Header()[k] = v
+			}
+
+			io.Copy(w, resp.Body)
+			return
+		}
+
+		if strings.Contains(r.Header.Get("User-Agent"), "Kobo") && kepubConverter.Available() {
+			epubFile := filepath.Join(dir, parseFileName(resp))
+			downloadFile(epubFile, resp)
+
+			kepubFile := filepath.Join(dir, strings.Replace(parseFileName(resp), ".epub", ".kepub.epub", 1))
+			kepubConverter.Convert(epubFile, kepubFile)
+			if err != nil {
+				handleError(r, w, "Failed to convert to kepub", err)
+			}
+
+			outFile, _ := os.Open(kepubFile)
+			defer outFile.Close()
+
+			outInfo, _ := outFile.Stat()
+
+			w.Header().Set("Content-Length", fmt.Sprintf("%d", outInfo.Size()))
+			w.Header().Set("Content-Disposition", mime.FormatMediaType("attachment", map[string]string{"filename": filepath.Base(kepubFile)}))
+			w.Header().Set("Content-Type", convert.EPUB_MIME)
+
+			io.Copy(w, outFile)
+
+			os.Remove(epubFile)
+			os.Remove(kepubFile)
+
+			return
+		}
+
+		if strings.Contains(r.Header.Get("User-Agent"), "Kindle") && mobiConverter.Available() {
+			epubFile := filepath.Join(dir, parseFileName(resp))
+			downloadFile(epubFile, resp)
+
+			mobiFile := filepath.Join(dir, strings.Replace(parseFileName(resp), ".epub", ".mobi", 1))
+			err := mobiConverter.Convert(epubFile, mobiFile)
+			if err != nil {
+				handleError(r, w, "Failed to convert to mobi", err)
+				return
+			}
+
+			outFile, _ := os.Open(mobiFile)
+			defer outFile.Close()
+
+			outInfo, _ := outFile.Stat()
+
+			w.Header().Set("Content-Length", fmt.Sprintf("%d", outInfo.Size()))
+			w.Header().Set("Content-Disposition", mime.FormatMediaType("attachment", map[string]string{"filename": filepath.Base(mobiFile)}))
+			w.Header().Set("Content-Type", convert.MOBI_MIME)
+
+			io.Copy(w, outFile)
+
+			os.Remove(epubFile)
+			os.Remove(mobiFile)
+
+			return
+		}
+
+		for k, v := range resp.Header {
+			w.Header()[k] = v
+		}
+
+		io.Copy(w, resp.Body)
+	}
+}
+
+func fetchFromUrl(url string) (*http.Response, error) {
+	client := &http.Client{
+		Timeout: 2 * time.Second,
+	}
+
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+	req.SetBasicAuth("public", "evanbuss")
+
+	return client.Do(req)
+}
+
+func handleError(r *http.Request, w http.ResponseWriter, message string, err error) {
+	slog.Error(message, slog.String("path", r.URL.RawPath), slog.Any("error", err))
+	http.Error(w, "An unexpected error occurred", http.StatusInternalServerError)
+}
+
+func replaceSearchPlaceHolder(url string, searchTerm string) string {
+	return strings.Replace(url, "{searchTerms}", searchTerm, 1)
+}
+
+func partial(req *http.Request) string {
+	return req.URL.Query().Get("partial")
+}
+
+func downloadFile(path string, resp *http.Response) {
+	file, err := os.Create(path)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+
+	_, err = io.Copy(file, resp.Body)
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+func parseFileName(resp *http.Response) string {
+	contentDisposition := resp.Header.Get("Content-Disposition")
+	_, params, err := mime.ParseMediaType(contentDisposition)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	return params["filename"]
+}