Here’s a short tutorial post showing how you can fire off a message to your Slack channel when using Postman’s low/no code feature Flows. The good news is this is really easy, and you don’t need to know how to code to do this.
TL:DR: Check out my short video here
Setup
1. go to https://api.slack.com/apps
2. click Create New App
3. select the workspace you want to post a message to
4. On the newly created app, select incoming Webhooks on left hand menu
5. Toggle Activation to ON
6. Click Add New Webhook to Workspace
7. Select Channel to post messages to. Copy cURL request.
8. Open Postman, click Import button
9. In Raw tab, paste the cURL request from Slack copied in step 7
10. Save request in a new collection (e.g. “Slack API)
11. Create a dynamic variable for request body message text AND webhook token (optional). Save variables in new Slack API environment.
12. Send the POST request. Confirm Slack message received (yay!) Save example in Postman.
13. Open your Flow. You can now add a Send Request Block for the POST Slack Message request, adding in a variable for the message you wish to send. Remember to add to the reject output of a conditional block if you only want to send if something has failed.
Et voila! Your message will now be posted into Slack should the condition fail to be met.
Or check out my video to see this working:-
Til next time!
Beth The Tester's Tales 
Hi Beth, well explained and good tutorials. Keep up the good work.
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