feat(Slack Node): Add option to include link to workflow in Slack node (#6611)

* feat(Slack Node): Add “automated by” message to Slack node’s post message

Signed-off-by: Oleg Ivaniv <me@olegivaniv.com>

* Pass instanceBaseUrl to node context

Signed-off-by: Oleg Ivaniv <me@olegivaniv.com>

* Move `includeLinkToWorkflow` to options

Signed-off-by: Oleg Ivaniv <me@olegivaniv.com>

* keep "includeLinkToWorkflow" hidden

* Only append the message for version 2.1 and up

Signed-off-by: Oleg Ivaniv <me@olegivaniv.com>

---------

Signed-off-by: Oleg Ivaniv <me@olegivaniv.com>
Co-authored-by: ricardo <ricardoespinoza105@gmail.com>

packages/nodes-base/nodes/Slack/V2/GenericFunctions.ts

@@ -7,7 +7,7 @@ import type {
 	IOAuth2Options,
 } from 'n8n-workflow';
 
-import { NodeOperationError } from 'n8n-workflow';
+import { NodeOperationError, jsonParse } from 'n8n-workflow';
 
 import get from 'lodash/get';
 
@@ -130,6 +130,64 @@ export async function slackApiRequestAllItems(
 	return returnData;
 }
 
+export function getMessageContent(
+	this: IExecuteFunctions | IExecuteSingleFunctions | ILoadOptionsFunctions,
+	i: number,
+) {
+	const nodeVersion = this.getNode().typeVersion;
+
+	const includeLinkToWorkflow = this.getNodeParameter(
+		'otherOptions.includeLinkToWorkflow',
+		i,
+		nodeVersion >= 2.1 ? true : false,
+	) as IDataObject;
+
+	const { id } = this.getWorkflow();
+	const automatedMessage = `_Automated with this <${this.getInstanceBaseUrl()}workflow/${id}|n8n workflow>_`;
+	const messageType = this.getNodeParameter('messageType', i) as string;
+
+	let content: IDataObject = {};
+	const text = this.getNodeParameter('text', i, '') as string;
+	switch (messageType) {
+		case 'text':
+			content = {
+				text: includeLinkToWorkflow ? `${text}\n${automatedMessage}` : text,
+			};
+			break;
+		case 'block':
+			content = jsonParse(this.getNodeParameter('blocksUi', i) as string);
+
+			if (includeLinkToWorkflow && Array.isArray(content.blocks)) {
+				content.blocks.push({
+					type: 'section',
+					text: {
+						type: 'mrkdwn',
+						text: automatedMessage,
+					},
+				});
+			}
+			if (text) {
+				content.text = text;
+			}
+			break;
+		case 'attachment':
+			content = { attachments: this.getNodeParameter('attachments', i) } as IDataObject;
+			if (includeLinkToWorkflow && Array.isArray(content.attachments)) {
+				content.attachments.push({
+					text: automatedMessage,
+				});
+			}
+			break;
+		default:
+			throw new NodeOperationError(
+				this.getNode(),
+				`The message type "${messageType}" is not known!`,
+			);
+	}
+
+	return content;
+}
+
 // tslint:disable-next-line:no-any
 export function validateJSON(json: string | undefined): any {
 	let result;