feat: add a test server

fixes #30

README.md

@@ -17,6 +17,18 @@ This repo is not be used standalone. It's used by the gateway code in go-ipfs. I
 1. Make changes to _both_ dir-index.html and dir-index-uncat.html.
 2. Follow the instructions in [go-ipfs](https://github.com/ipfs/go-ipfs/tree/master/assets#updating-dir-index-html) for updating the directory index.
 
+## Testing
+
+1. Install [go](https://golang.org/dl/).
+2. Run the test server:
+
+```bash
+> cd test
+> go run .
+```
+
+This will listen on `localhost:3000` and re-load the template every time you refresh the page.
+
 ## Contribute
 
 Feel free to join in. All welcome. A good place to start is [the issues](https://github.com/ipfs/dir-index-html/issues).

test/go.mod

+module github.com/ipfs/dir-index-html/test
+
+go 1.14

test/main.go

+package main
+
+import (
+	"fmt"
+	"net/http"
+	"net/url"
+	"os"
+	"text/template"
+)
+
+const templateFile = "../dir-index.html"
+
+// Copied from go-ipfs/core/corehttp/gateway_indexPage.go
+type listingTemplateData struct {
+	Listing  []directoryItem
+	Path     string
+	BackLink string
+	Hash     string
+}
+
+type directoryItem struct {
+	Size string
+	Name string
+	Path string
+}
+
+var testData = listingTemplateData{
+	Listing: []directoryItem{{
+		Size: "25 MiB",
+		Name: "short-film.mov",
+		Path: "short-film.mov",
+	}, {
+		Size: "1 KiB",
+		Name: "description.txt",
+		Path: "description.txt",
+	}},
+	Path:     "/ipfs/QmFoo",
+	BackLink: "/..",
+	Hash:     "QmFoo",
+}
+
+func main() {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/" {
+			http.Error(w, "Ha-ha, tricked you! There are no files here!", http.StatusNotFound)
+			return
+		}
+		listingTemplate, err := template.New("dir-index.html").Funcs(template.FuncMap{
+			"iconFromExt": func(name string) string {
+				return "ipfs-_blank" // place-holder
+			},
+			"urlEscape": func(rawUrl string) string {
+				pathUrl := url.URL{Path: rawUrl}
+				return pathUrl.String()
+			},
+		}).ParseFiles(templateFile)
+		if err != nil {
+			http.Error(w, fmt.Sprintf("failed to parse template file: %s", err), http.StatusInternalServerError)
+			return
+		}
+		err = listingTemplate.Execute(w, &testData)
+		if err != nil {
+			http.Error(w, fmt.Sprintf("failed to execute template: %s", err), http.StatusInternalServerError)
+			return
+		}
+		w.WriteHeader(http.StatusOK)
+	})
+	if _, err := os.Stat(templateFile); err != nil {
+		wd, _ := os.Getwd()
+		fmt.Printf("could not open template file %q, relative to %q: %s\n", templateFile, wd, err)
+		os.Exit(1)
+	}
+	fmt.Printf("listening on localhost:3000\n")
+	http.ListenAndServe("localhost:3000", mux)
+}