Automation library · Content

Prevent duplicate webhook processing with Postgres

Started by another system calling it, and works across Postgres. 9 steps, 1 branch: a working afternoon to understand properly.

Medium

9 stepsMedium: a working afternoon
1Branch: places the flow splits
0Loops or waits
1Service it connects to

The flow

Starts it 2Logic 4Service 3

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

  1. 1Webhook TriggerWebhookStarts it
  2. 2Daily CleanupSchedule triggerStarts it
  3. 3Hash PayloadCryptoService
  4. 4ConfigSetLogic
  5. 5Claim (insert if new)PostgresService
  6. 6Cleanup Old HashesPostgresService
  7. 7Is New?IfLogic
  8. 8Process PayloadCodeLogic
  9. 9Skip DuplicateCodeLogic

How it's built

Starts on
Another system calling it
Steps
9, with 1 branch
Size
Medium: a working afternoon
Connects to
Postgres
Model
None. This is plumbing, not judgement

Questions

What does it need to run?

An n8n account, plus your own Postgres account. 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. 9 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 9 steps before you point it at anything that matters.