Automation library · Content

Route human-in-the-loop approval requests with Slack

Started by another system calling it, and works across Postgres and Slack. 17 steps, 2 branches: a working afternoon to understand properly.

Medium

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17 stepsMedium: a working afternoon
2Branches: places the flow splits
0Loops or waits
2Services it connects to

The flow

Starts it 3Logic 9Service 5

The steps in the order they run, from what starts it.

  1. 1Receive Slack POST RequestWebhookStarts it
  2. 2Verify Slack Request SignatureCodeLogic
  3. 3Determine Slack Request TypeCodeLogic
  4. 4Route by Request TypeIfLogic
  5. 5Create Slack Block MessageCodeLogic
  6. 6Handle Slack Callback DataCodeLogic
  7. 7Send Message to Slack ChannelSlackService
  8. 8Acknowledge Slack Callback FastRespond To WebhookStarts it
  9. 9Check Slack Response ValidityCodeLogic
  10. 10Retrieve Context from DatabasePostgresService
  11. 11Log Request in DatabasePostgresService
  12. 12Combine Callback with DB ContextCodeLogic
  13. 13Acknowledge Intake with 200 OKRespond To WebhookStarts it
  14. 14Update Slack Message ContentCodeLogic
  15. 15Modify Slack Message to FinalSlackService
  16. 16Record Decision in DatabasePostgresService
  17. 17Determine Next Action TakenIfLogic

How it's built

Starts on
Another system calling it
Steps
17, with 2 branches
Size
Medium: a working afternoon
Connects to
Postgres, Slack
Model
None. This is plumbing, not judgement

Questions

What does it need to run?

An n8n account, plus your own Postgres and Slack accounts. You connect your own accounts after importing it; none are included.

What starts it?

It starts on another system calling it.

Does it use AI?

No. Every step is fixed logic or a call to a service, so it does the same thing every time.

How long does it take to set up?

Plan an afternoon. 17 steps is enough that you should read each one before running it.

How do I import it?

Copy the workflow, open a new workflow in n8n and paste. The steps appear on the canvas, ready for your own accounts.

Before you run it

Nothing here has been tested by us. It is somebody's working automation, read and described from its own steps. Treat the connections it wants as a list of accounts it will touch, and read the 17 steps before you point it at anything that matters.