PLT-6965 jira integration (plus plugin scaffolding) (#6918)

* plugin scaffolding / jira integration

* add vendored testify packages

* webhook fix

* don't change i18n ids

* support configuration watching

* add basic jira plugin configuration to admin console

* fix eslint errors

* fix another eslint warning

* polish

* undo unintentional config.json commit >:(

* test fix

* add jira plugin diagnostics, remove dm support, add bot tag, generate web-safe secrets

* rebase, implement requested changes

* requested changes

* remove tests and minimize makefile change

* add missing license headers

* add missing comma

* remove bad line from Makefile

app/webhook.go

@@ -490,48 +490,43 @@ func HandleIncomingWebhook(hookId string, req *model.IncomingWebhookRequest) *mo
 
 	var channel *model.Channel
 	var cchan store.StoreChannel
-	var directUserId string
 
 	if len(channelName) != 0 {
 		if channelName[0] == '@' {
 			if result := <-Srv.Store.User().GetByUsername(channelName[1:]); result.Err != nil {
 				return model.NewAppError("HandleIncomingWebhook", "web.incoming_webhook.user.app_error", nil, "err="+result.Err.Message, http.StatusBadRequest)
 			} else {
-				directUserId = result.Data.(*model.User).Id
-				channelName = model.GetDMNameFromIds(directUserId, hook.UserId)
+				if ch, err := GetDirectChannel(hook.UserId, result.Data.(*model.User).Id); err != nil {
+					return err
+				} else {
+					channel = ch
+				}
 			}
 		} else if channelName[0] == '#' {
-			channelName = channelName[1:]
+			cchan = Srv.Store.Channel().GetByName(hook.TeamId, channelName[1:], true)
+		} else {
+			cchan = Srv.Store.Channel().GetByName(hook.TeamId, channelName, true)
 		}
-
-		cchan = Srv.Store.Channel().GetByName(hook.TeamId, channelName, true)
 	} else {
 		cchan = Srv.Store.Channel().Get(hook.ChannelId, true)
 	}
 
-	overrideUsername := req.Username
-	overrideIconUrl := req.IconURL
-
-	result := <-cchan
-	if result.Err != nil && result.Err.Id == store.MISSING_CHANNEL_ERROR && directUserId != "" {
-		newChanResult := <-Srv.Store.Channel().CreateDirectChannel(directUserId, hook.UserId)
-		if newChanResult.Err != nil {
-			return model.NewAppError("HandleIncomingWebhook", "web.incoming_webhook.channel.app_error", nil, "err="+newChanResult.Err.Message, http.StatusBadRequest)
+	if channel == nil {
+		result := <-cchan
+		if result.Err != nil {
+			return model.NewAppError("HandleIncomingWebhook", "web.incoming_webhook.channel.app_error", nil, "err="+result.Err.Message, result.Err.StatusCode)
 		} else {
-			channel = newChanResult.Data.(*model.Channel)
-			InvalidateCacheForUser(directUserId)
-			InvalidateCacheForUser(hook.UserId)
+			channel = result.Data.(*model.Channel)
 		}
-	} else if result.Err != nil {
-		return model.NewAppError("HandleIncomingWebhook", "web.incoming_webhook.channel.app_error", nil, "err="+result.Err.Message, result.Err.StatusCode)
-	} else {
-		channel = result.Data.(*model.Channel)
 	}
 
 	if channel.Type != model.CHANNEL_OPEN && !HasPermissionToChannel(hook.UserId, channel.Id, model.PERMISSION_READ_CHANNEL) {
 		return model.NewAppError("HandleIncomingWebhook", "web.incoming_webhook.permissions.app_error", nil, "", http.StatusForbidden)
 	}
 
+	overrideUsername := req.Username
+	overrideIconUrl := req.IconURL
+
 	if _, err := CreateWebhookPost(hook.UserId, hook.TeamId, channel.Id, text, overrideUsername, overrideIconUrl, req.Props, webhookType); err != nil {
 		return err
 	}