Generate Layerre image variants from a webhook and post them to Slack

Input: JSON from a form or API (name, image URL) → Process: Layerre renders a Canva-based variant → Output: Slack message + webhook response with image URL

Who

Operators or developers with a Canva design, Layerre account, and Slack workspace

You get

On each webhook request, auto-generate a personalized image, post it to Slack, and return the image URL

You need

n8n · webhook · slack

Steps

1. Prepare: create the Layerre template and configure the Webhook

   Import the workflow into n8n. Run the Create a template node once: paste your Canva design URL and execute, then note the generated template ID. Configure the Webhook node: set HTTP Method to POST, Path to layerre-image, and Response Mode to responseNode. Your form or app must send JSON to this webhook URL, for example {"name":"Jane","imageUrl":"https://..."}.

   Setup guidance · Source text。Workflow Overview sticky note; overall setup reference

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   ## Webhook → Layerre → Slack
   
   Generate a custom image from incoming webhook data (e.g. form submissions, Typeform, Tally, or custom API) and post the result to a Slack channel.
   
   ### How it works
   1. **Webhook**: Receives POST with JSON body (e.g. `{"name": "Jane", "imageUrl": "https://..."}`)
   2. **Create Template** (run once manually): Create a Layerre template from your Canva design, then select it in the variant node
   3. **Create Variant**: On each webhook, build one variant using body fields
   4. **Slack**: Post the rendered image URL (or message) to a channel
   
   ### Prerequisites
   - [Layerre account](https://layerre.com) with API key
   - Canva design with customizable layers
   - Slack workspace and app (incoming webhook or Bot token)
   
   ### Customization
   - Map webhook body fields to your Canva layer IDs in the Create Variant node
   - Use Respond to Webhook to return the image URL in the HTTP response
   - Add error handling or rate limiting as needed
   
   ### Resources
   - [Layerre Documentation](https://layerre.com/docs)
   - [Layerre n8n Node](https://github.com/layerre/n8n-nodes-layerre)

   Setup guidance · Source text。Create a template node instructions

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   ## Step 1: Create Template (one-time, run manually)
   
   Run this node once: paste your Canva design URL and execute. Then in **Create Variant from Webhook**, select that template from the **Template** dropdown. This node is not in the webhook path.

2. Map fields: link webhook data to Canva layers in the Variant node

   Open the Create a variant node. Select the template created in Step 1 from the Template dropdown. In Overrides, map webhook JSON fields to Canva layers: for example, $json.body.name to a text layer and $json.body.imageUrl to an image layer. The source example also mentions photoUrl; use the field names your form actually sends.

   Execution prompt · Source text。Create a variant node Overrides configuration

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   ## Step 2: Create Variant from webhook body
   
   Select your template from the **Template** dropdown (from Step 1). Map webhook JSON fields to your Canva layers. Example body: `{"name": "Jane", "photoUrl": "https://..."}`. Overrides use `$json.body.name` and `$json.body.photoUrl`.

3. Output: post to Slack and return the webhook response

   Configure the Post to Slack node: add Slack credentials and choose the target channel or user; the default message is "New image: {{ $json.url }}", which you can customize. Then configure the Respond to Webhook node: set respondWith to json and responseBody to ={{ { "success": true, "imageUrl": $json.renderedImageUrl || $json.imageUrl } }} so the caller receives the image link. Save and activate the workflow.

   Execution prompt · Source text。Post to Slack node instructions

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   ## Step 3: Post to Slack
   
   Send the rendered image URL (or a message) to a Slack channel. Configure your Slack credentials and channel.

Use the following information to build or reproduce this workflow in n8n:
1) Import the workflow JSON (source template ID 13880).
2) Run the Create a template node once manually, paste your Canva URL, and obtain the template ID.
3) Configure the Webhook node path and method, ensuring external systems send POST JSON with the agreed fields.
4) In the Create a variant node, select the template and map body fields to Canva layers.
5) Configure Slack credentials and the response node so each request generates an image, posts to Slack, and returns the URL.
Note: you need your own Layerre API key, Canva design, and Slack credentials; test manually with sample data before going live.