Merge pull request hashicorp#122 from hashicorp/f-http-getter-headers

HttpGetter: Add ability to set headers

get_http.go

@@ -41,6 +41,12 @@ type HttpGetter struct {
 	// Client is the http.Client to use for Get requests.
 	// This defaults to a cleanhttp.DefaultClient if left unset.
 	Client *http.Client
+
+	// Header contains optional request header fields that should be included
+	// with every HTTP request. Note that the zero value of this field is nil,
+	// and as such it needs to be initialized before use, via something like
+	// make(http.Header).
+	Header http.Header
 }
 
 func (g *HttpGetter) ClientMode(u *url.URL) (ClientMode, error) {
@@ -72,10 +78,17 @@ func (g *HttpGetter) Get(dst string, u *url.URL) error {
 	u.RawQuery = q.Encode()
 
 	// Get the URL
-	resp, err := g.Client.Get(u.String())
+	req, err := http.NewRequest("GET", u.String(), nil)
+	if err != nil {
+		return err
+	}
+
+	req.Header = g.Header
+	resp, err := g.Client.Do(req)
 	if err != nil {
 		return err
 	}
+
 	defer resp.Body.Close()
 	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
 		return fmt.Errorf("bad response code: %d", resp.StatusCode)
@@ -118,10 +131,17 @@ func (g *HttpGetter) GetFile(dst string, u *url.URL) error {
 		g.Client = httpClient
 	}
 
-	resp, err := g.Client.Get(u.String())
+	req, err := http.NewRequest("GET", u.String(), nil)
 	if err != nil {
 		return err
 	}
+
+	req.Header = g.Header
+	resp, err := g.Client.Do(req)
+	if err != nil {
+		return err
+	}
+
 	defer resp.Body.Close()
 	if resp.StatusCode != 200 {
 		return fmt.Errorf("bad response code: %d", resp.StatusCode)

get_http_test.go

@@ -40,6 +40,34 @@ func TestHttpGetter_header(t *testing.T) {
 	}
 }
 
+func TestHttpGetter_requestHeader(t *testing.T) {
+	ln := testHttpServer(t)
+	defer ln.Close()
+
+	g := new(HttpGetter)
+	g.Header = make(http.Header)
+	g.Header.Add("X-Foobar", "foobar")
+	dst := tempDir(t)
+	defer os.RemoveAll(dst)
+
+	var u url.URL
+	u.Scheme = "http"
+	u.Host = ln.Addr().String()
+	u.Path = "/expect-header"
+	u.RawQuery = "expected=X-Foobar"
+
+	// Get it!
+	if err := g.GetFile(dst, &u); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	// Verify the main file exists
+	if _, err := os.Stat(dst); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	assertContents(t, dst, "Hello\n")
+}
+
 func TestHttpGetter_meta(t *testing.T) {
 	ln := testHttpServer(t)
 	defer ln.Close()
@@ -255,6 +283,7 @@ func testHttpServer(t *testing.T) net.Listener {
 	}
 
 	mux := http.NewServeMux()
+	mux.HandleFunc("/expect-header", testHttpHandlerExpectHeader)
 	mux.HandleFunc("/file", testHttpHandlerFile)
 	mux.HandleFunc("/header", testHttpHandlerHeader)
 	mux.HandleFunc("/meta", testHttpHandlerMeta)
@@ -269,6 +298,17 @@ func testHttpServer(t *testing.T) net.Listener {
 	return ln
 }
 
+func testHttpHandlerExpectHeader(w http.ResponseWriter, r *http.Request) {
+	if expected, ok := r.URL.Query()["expected"]; ok {
+		if r.Header.Get(expected[0]) != "" {
+			w.Write([]byte("Hello\n"))
+			return
+		}
+	}
+
+	w.WriteHeader(400)
+}
+
 func testHttpHandlerFile(w http.ResponseWriter, r *http.Request) {
 	w.Write([]byte("Hello\n"))
 }