[MM-16934] Add API endpoint to update channel privacy (#11993)

* Add API endpoint to update channel privacy setting

* Fix language files

* Improve tests by making sure channel has been updated correctly

* Improve tests

api4/channel.go

@@ -35,6 +35,7 @@ func (api *API) InitChannel() {
 	api.BaseRoutes.Channel.Handle("", api.ApiSessionRequired(updateChannel)).Methods("PUT")
 	api.BaseRoutes.Channel.Handle("/patch", api.ApiSessionRequired(patchChannel)).Methods("PUT")
 	api.BaseRoutes.Channel.Handle("/convert", api.ApiSessionRequired(convertChannelToPrivate)).Methods("POST")
+	api.BaseRoutes.Channel.Handle("/privacy", api.ApiSessionRequired(updateChannelPrivacy)).Methods("PUT")
 	api.BaseRoutes.Channel.Handle("/restore", api.ApiSessionRequired(restoreChannel)).Methods("POST")
 	api.BaseRoutes.Channel.Handle("", api.ApiSessionRequired(deleteChannel)).Methods("DELETE")
 	api.BaseRoutes.Channel.Handle("/stats", api.ApiSessionRequired(getChannelStats)).Methods("GET")
@@ -229,6 +230,54 @@ func convertChannelToPrivate(c *Context, w http.ResponseWriter, r *http.Request)
 	w.Write([]byte(rchannel.ToJson()))
 }
 
+func updateChannelPrivacy(c *Context, w http.ResponseWriter, r *http.Request) {
+	c.RequireChannelId()
+	if c.Err != nil {
+		return
+	}
+
+	props := model.StringInterfaceFromJson(r.Body)
+	privacy, ok := props["privacy"].(string)
+	if !ok || (privacy != model.CHANNEL_OPEN && privacy != model.CHANNEL_PRIVATE) {
+		c.SetInvalidParam("privacy")
+		return
+	}
+
+	channel, err := c.App.GetChannel(c.Params.ChannelId)
+	if err != nil {
+		c.Err = err
+		return
+	}
+
+	if !c.App.SessionHasPermissionToTeam(c.App.Session, channel.TeamId, model.PERMISSION_MANAGE_TEAM) {
+		c.SetPermissionError(model.PERMISSION_MANAGE_TEAM)
+		return
+	}
+
+	if channel.Name == model.DEFAULT_CHANNEL && privacy == model.CHANNEL_PRIVATE {
+		c.Err = model.NewAppError("updateChannelPrivacy", "api.channel.update_channel_privacy.default_channel_error", nil, "", http.StatusBadRequest)
+		return
+	}
+
+	user, err := c.App.GetUser(c.App.Session.UserId)
+	if err != nil {
+		c.Err = err
+		return
+	}
+
+	channel.Type = privacy
+
+	updatedChannel, err := c.App.UpdateChannelPrivacy(channel, user)
+	if err != nil {
+		c.Err = err
+		return
+	}
+
+	c.LogAudit("name=" + updatedChannel.Name)
+
+	w.Write([]byte(updatedChannel.ToJson()))
+}
+
 func patchChannel(c *Context, w http.ResponseWriter, r *http.Request) {
 	c.RequireChannelId()
 	if c.Err != nil {

api4/channel_test.go

@@ -1387,6 +1387,68 @@ func TestConvertChannelToPrivate(t *testing.T) {
 	}
 }
 
+func TestUpdateChannelPrivacy(t *testing.T) {
+	th := Setup().InitBasic()
+	defer th.TearDown()
+	Client := th.Client
+
+	type testTable []struct {
+		name            string
+		channel         *model.Channel
+		expectedPrivacy string
+	}
+
+	defaultChannel, _ := th.App.GetChannelByName(model.DEFAULT_CHANNEL, th.BasicTeam.Id, false)
+	privateChannel := th.CreatePrivateChannel()
+	publicChannel := th.CreatePublicChannel()
+
+	tt := testTable{
+		{"Updating default channel should fail with forbidden status if not logged in", defaultChannel, model.CHANNEL_OPEN},
+		{"Updating private channel should fail with forbidden status if not logged in", privateChannel, model.CHANNEL_PRIVATE},
+		{"Updating public channel should fail with forbidden status if not logged in", publicChannel, model.CHANNEL_OPEN},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			_, resp := Client.UpdateChannelPrivacy(tc.channel.Id, tc.expectedPrivacy)
+			CheckForbiddenStatus(t, resp)
+		})
+	}
+
+	th.LoginTeamAdmin()
+
+	tt = testTable{
+		{"Converting default channel to private should fail", defaultChannel, model.CHANNEL_PRIVATE},
+		{"Updating privacy to an invalid setting should fail", publicChannel, "invalid"},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			_, resp := Client.UpdateChannelPrivacy(tc.channel.Id, tc.expectedPrivacy)
+			CheckBadRequestStatus(t, resp)
+		})
+	}
+
+	tt = testTable{
+		{"Default channel should stay public", defaultChannel, model.CHANNEL_OPEN},
+		{"Public channel should stay public", publicChannel, model.CHANNEL_OPEN},
+		{"Private channel should stay private", privateChannel, model.CHANNEL_PRIVATE},
+		{"Public channel should convert to private", publicChannel, model.CHANNEL_PRIVATE},
+		{"Private channel should convert to public", privateChannel, model.CHANNEL_OPEN},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			updatedChannel, resp := Client.UpdateChannelPrivacy(tc.channel.Id, tc.expectedPrivacy)
+			CheckNoError(t, resp)
+			assert.Equal(t, updatedChannel.Type, tc.expectedPrivacy)
+			updatedChannel, err := th.App.GetChannel(tc.channel.Id)
+			require.Nil(t, err)
+			assert.Equal(t, updatedChannel.Type, tc.expectedPrivacy)
+		})
+	}
+}
+
 func TestRestoreChannel(t *testing.T) {
 	th := Setup().InitBasic()
 	defer th.TearDown()