support host directive in config (#7)

This allows for the service to be proxied as a service in a larger site.

README.md

@@ -23,6 +23,7 @@ Edit `vanity.yaml` to add any number of git repos. E.g., `customdomain.com/portm
 serve the [https://github.com/rakyll/portmidi](https://github.com/rakyll/portmidi) repo.
 
 ```
+paths:
   /portmidi:
     repo: https://github.com/rakyll/portmidi
 ```

appengine.go

@@ -37,6 +37,6 @@ func main() {
 	appengine.Main()
 }
 
-func requestHost(r *http.Request) string {
+func defaultHost(r *http.Request) string {
 	return appengine.DefaultVersionHostname(appengine.NewContext(r))
 }

handler.go

@@ -38,16 +38,19 @@ type pathConfig struct {
 }
 
 func newHandler(config []byte) (*handler, error) {
-	var m map[string]struct {
+	var parsed struct {
+		Host  string `yaml:"host,omitempty"`
+		Paths map[string]struct {
 			Repo    string `yaml:"repo,omitempty"`
 			Display string `yaml:"display,omitempty"`
 			VCS     string `yaml:"vcs,omitempty"`
+		} `yaml:"paths,omitempty"`
 	}
-	if err := yaml.Unmarshal(config, &m); err != nil {
+	if err := yaml.Unmarshal(config, &parsed); err != nil {
 		return nil, err
 	}
-	h := new(handler)
+	h := &handler{host: parsed.Host}
-	for path, e := range m {
+	for path, e := range parsed.Paths {
 		pc := pathConfig{
 			path:    strings.TrimSuffix(path, "/"),
 			repo:    e.Repo,
@@ -89,7 +92,7 @@ func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 	host := h.host
 	if host == "" {
-		host = requestHost(r)
+		host = defaultHost(r)
 	}
 	if err := vanityTmpl.Execute(w, struct {
 		Import  string

handler_test.go

@@ -34,7 +34,9 @@ func TestHandler(t *testing.T) {
 	}{
 		{
 			name: "explicit display",
-			config: "/portmidi:\n" +
+			config: "host: example.com\n" +
+				"paths:\n" +
+				"  /portmidi:\n" +
 				"    repo: https://github.com/rakyll/portmidi\n" +
 				"    display: https://github.com/rakyll/portmidi _ _\n",
 			path:     "/portmidi",
@@ -43,7 +45,9 @@ func TestHandler(t *testing.T) {
 		},
 		{
 			name: "display GitHub inference",
-			config: "/portmidi:\n" +
+			config: "host: example.com\n" +
+				"paths:\n" +
+				"  /portmidi:\n" +
 				"    repo: https://github.com/rakyll/portmidi\n",
 			path:     "/portmidi",
 			goImport: "example.com/portmidi git https://github.com/rakyll/portmidi",
@@ -51,7 +55,9 @@ func TestHandler(t *testing.T) {
 		},
 		{
 			name: "Bitbucket Mercurial",
-			config: "/gopdf:\n" +
+			config: "host: example.com\n" +
+				"paths:\n" +
+				"  /gopdf:\n" +
 				"    repo: https://bitbucket.org/zombiezen/gopdf\n" +
 				"    vcs: hg\n",
 			path:     "/gopdf",
@@ -60,7 +66,9 @@ func TestHandler(t *testing.T) {
 		},
 		{
 			name: "Bitbucket Git",
-			config: "/mygit:\n" +
+			config: "host: example.com\n" +
+				"paths:\n" +
+				"  /mygit:\n" +
 				"    repo: https://bitbucket.org/zombiezen/mygit\n" +
 				"    vcs: git\n",
 			path:     "/mygit",
@@ -69,7 +77,9 @@ func TestHandler(t *testing.T) {
 		},
 		{
 			name: "subpath",
-			config: "/portmidi:\n" +
+			config: "host: example.com\n" +
+				"paths:\n" +
+				"  /portmidi:\n" +
 				"    repo: https://github.com/rakyll/portmidi\n" +
 				"    display: https://github.com/rakyll/portmidi _ _\n",
 			path:     "/portmidi/foo",
@@ -78,7 +88,9 @@ func TestHandler(t *testing.T) {
 		},
 		{
 			name: "subpath with trailing config slash",
-			config: "/portmidi/:\n" +
+			config: "host: example.com\n" +
+				"paths:\n" +
+				"  /portmidi/:\n" +
 				"    repo: https://github.com/rakyll/portmidi\n" +
 				"    display: https://github.com/rakyll/portmidi _ _\n",
 			path:     "/portmidi/foo",
@@ -92,7 +104,6 @@ func TestHandler(t *testing.T) {
 			t.Errorf("%s: newHandler: %v", test.name, err)
 			continue
 		}
-		h.host = "example.com"
 		s := httptest.NewServer(h)
 		resp, err := http.Get(s.URL + test.path)
 		if err != nil {
@@ -121,8 +132,10 @@ func TestHandler(t *testing.T) {
 
 func TestBadConfigs(t *testing.T) {
 	badConfigs := []string{
+		"paths:\n" +
 			"  /missingvcs:\n" +
 			"    repo: https://bitbucket.org/zombiezen/gopdf\n",
+		"paths:\n" +
 			"  /unknownvcs:\n" +
 			"    repo: https://bitbucket.org/zombiezen/gopdf\n" +
 			"    vcs: xyzzy\n",

main.go

@@ -41,6 +41,6 @@ func main() {
 	}
 }
 
-func requestHost(r *http.Request) string {
+func defaultHost(r *http.Request) string {
 	return r.Host
 }

vanity.yaml

@@ -1,3 +1,4 @@
+paths:
   /portmidi:
     repo: https://github.com/rakyll/portmidi