Update docs and test of exec create api return codes

Fixes issue #18054

Signed-off-by: Wen Cheng Ma <wenchma@cn.ibm.com>

daemon/exec.go

@@ -108,7 +108,7 @@ func (d *Daemon) getExecConfig(name string) (*ExecConfig, error) {
 	ec := d.execCommands.Get(name)
 
 	// If the exec is found but its container is not in the daemon's list of
-	// containers then it must have been delete, in which case instead of
+	// containers then it must have been deleted, in which case instead of
 	// saying the container isn't running, we should return a 404 so that
 	// the user sees the same error now that they will after the
 	// 5 minute clean-up loop is run which erases old/dead execs.

docs/reference/api/docker_remote_api_v1.21.md

@@ -2256,6 +2256,8 @@ Status Codes:
 
 -   **201** – no error
 -   **404** – no such container
+-   **409** - container is paused
+-   **500** - server error
 
 ### Exec Start
 
@@ -2291,7 +2293,7 @@ Status Codes:
 
 -   **200** – no error
 -   **404** – no such exec instance
--   **409** - container is stopped or paused
+-   **409** - container is paused
 
     **Stream details**:
     Similar to the stream behavior of `POST /container/(id)/attach` API

docs/reference/api/docker_remote_api_v1.22.md

@@ -2263,6 +2263,8 @@ Status Codes:
 
 -   **201** – no error
 -   **404** – no such container
+-   **409** - container is paused
+-   **500** - server error
 
 ### Exec Start
 
@@ -2298,7 +2300,7 @@ Status Codes:
 
 -   **200** – no error
 -   **404** – no such exec instance
--   **409** - container is stopped or paused
+-   **409** - container is paused
 
     **Stream details**:
     Similar to the stream behavior of `POST /container/(id)/attach` API

integration-cli/docker_api_exec_test.go

@@ -49,6 +49,21 @@ func (s *DockerSuite) TestExecApiCreateNoValidContentType(c *check.C) {
 	}
 }
 
+func (s *DockerSuite) TestExecApiCreateContainerPaused(c *check.C) {
+	testRequires(c, DaemonIsLinux)
+	name := "exec_create_test"
+	dockerCmd(c, "run", "-d", "-t", "--name", name, "busybox", "/bin/sh")
+
+	dockerCmd(c, "pause", name)
+	status, body, err := sockRequest("POST", fmt.Sprintf("/containers/%s/exec", name), map[string]interface{}{"Cmd": []string{"true"}})
+	c.Assert(err, check.IsNil)
+	c.Assert(status, check.Equals, http.StatusConflict)
+
+	if !bytes.Contains(body, []byte("Container "+name+" is paused, unpause the container before exec")) {
+		c.Fatalf("Expected message when creating exec command with Container %s is paused", name)
+	}
+}
+
 func (s *DockerSuite) TestExecAPIStart(c *check.C) {
 	dockerCmd(c, "run", "-d", "--name", "test", "busybox", "top")