@@ -51,6 +51,24 @@ func hijackServer(w http.ResponseWriter) (io.ReadCloser, io.Writer, error) {

 	return conn, conn, nil

 }

+// Check to make sure request's Content-Type is application/json

+func checkForJson(r *http.Request) error {

+	ct := r.Header.Get("Content-Type")

+

+	// No Content-Type header is ok as long as there's no Body

+	if ct == "" {

+		if r.Body == nil || r.ContentLength == 0 {

+			return nil

+		}

+	}

+

+	// Otherwise it better be json

+	if api.MatchesContentType(ct, "application/json") {

+		return nil

+	}

+	return fmt.Errorf("Content-Type specified (%s) must be 'application/json'", ct)

+}

+

 //If we don't do this, POST method without Content-type (even with empty body) will fail

 func parseForm(r *http.Request) error {

 	if r == nil {

@@ -445,6 +463,11 @@ func postCommit(eng *engine.Engine, version version.Version, w http.ResponseWrit

 		job          = eng.Job("commit", r.Form.Get("container"))

 		stdoutBuffer = bytes.NewBuffer(nil)

 	)

+

+	if err := checkForJson(r); err != nil {

+		return err

+	}

+

 	if err := config.Decode(r.Body); err != nil {

 		log.Errorf("%s", err)

 	}

@@ -651,6 +674,11 @@ func postContainersCreate(eng *engine.Engine, version version.Version, w http.Re

 		stdoutBuffer = bytes.NewBuffer(nil)

 		warnings     = bytes.NewBuffer(nil)

 	)

+

+	if err := checkForJson(r); err != nil {

+		return err

+	}

+

 	if err := job.DecodeEnv(r.Body); err != nil {

 		return err

 	}

@@ -734,8 +762,8 @@ func postContainersStart(eng *engine.Engine, version version.Version, w http.Res

 	// allow a nil body for backwards compatibility

 	if r.Body != nil && r.ContentLength > 0 {

-		if !api.MatchesContentType(r.Header.Get("Content-Type"), "application/json") {

-			return fmt.Errorf("Content-Type of application/json is required")

+		if err := checkForJson(r); err != nil {

+			return err

 		}

 		if err := job.DecodeEnv(r.Body); err != nil {

@@ -1001,12 +1029,12 @@ func postContainersCopy(eng *engine.Engine, version version.Version, w http.Resp

 	var copyData engine.Env

-	if contentType := r.Header.Get("Content-Type"); api.MatchesContentType(contentType, "application/json") {

-		if err := copyData.Decode(r.Body); err != nil {

-			return err

-		}

-	} else {

-		return fmt.Errorf("Content-Type not supported: %s", contentType)

+	if err := checkForJson(r); err != nil {

+		return err

+	}

+

+	if err := copyData.Decode(r.Body); err != nil {

+		return err

 	}

 	if copyData.Get("Resource") == "" {

@@ -1043,6 +1071,7 @@ func postContainerExecCreate(eng *engine.Engine, version version.Version, w http

 		job          = eng.Job("execCreate", name)

 		stdoutBuffer = bytes.NewBuffer(nil)

 	)

+

 	if err := job.DecodeEnv(r.Body); err != nil {

 		return err

 	}

@@ -1068,6 +1097,7 @@ func postContainerExecStart(eng *engine.Engine, version version.Version, w http.

 		job              = eng.Job("execStart", name)

 		errOut io.Writer = os.Stderr

 	)

+

 	if err := job.DecodeEnv(r.Body); err != nil {

 		return err

 	}

@@ -9,6 +9,7 @@ import (

 	"net"

 	"net/http"

 	"net/http/httptest"

+	"strings"

 	"testing"

 	"time"

@@ -356,6 +357,8 @@ func TestPostContainersCreate(t *testing.T) {

 		t.Fatal(err)

 	}

+	req.Header.Set("Content-Type", "application/json")

+

 	r := httptest.NewRecorder()

 	if err := server.ServeRequest(eng, api.APIVERSION, r, req); err != nil {

 		t.Fatal(err)

@@ -379,6 +382,49 @@ func TestPostContainersCreate(t *testing.T) {

 	}

 }

+func TestPostJsonVerify(t *testing.T) {

+	eng := NewTestEngine(t)

+	defer mkDaemonFromEngine(eng, t).Nuke()

+

+	configJSON, err := json.Marshal(&runconfig.Config{

+		Image:  unitTestImageID,

+		Memory: 33554432,

+		Cmd:    []string{"touch", "/test"},

+	})

+	if err != nil {

+		t.Fatal(err)

+	}

+

+	req, err := http.NewRequest("POST", "/containers/create", bytes.NewReader(configJSON))

+	if err != nil {

+		t.Fatal(err)

+	}

+

+	r := httptest.NewRecorder()

+

+	if err := server.ServeRequest(eng, api.APIVERSION, r, req); err != nil {

+		t.Fatal(err)

+	}

+

+	// Don't add Content-Type header

+	// req.Header.Set("Content-Type", "application/json")

+

+	err = server.ServeRequest(eng, api.APIVERSION, r, req)

+	if r.Code != http.StatusInternalServerError || !strings.Contains(((*r.Body).String()), "application/json") {

+		t.Fatal("Create should have failed due to no Content-Type header - got:", r)

+	}

+

+	// Now add header but with wrong type and retest

+	req.Header.Set("Content-Type", "application/xml")

+

+	if err := server.ServeRequest(eng, api.APIVERSION, r, req); err != nil {

+		t.Fatal(err)

+	}

+	if r.Code != http.StatusInternalServerError || !strings.Contains(((*r.Body).String()), "application/json") {

+		t.Fatal("Create should have failed due to wrong Content-Type header - got:", r)

+	}

+}

+

 func TestPostContainersKill(t *testing.T) {

 	eng := NewTestEngine(t)

 	defer mkDaemonFromEngine(eng, t).Nuke()