How do I send a screenshot from n8n's cloud to Slack after a webhook response?

Below is one way to accomplish this in n8n:

1. Chain your Webhook and Slack nodes sequentially.
   First, have your Webhook node trigger your workflow, then use a Respond node to send the webhook response. After that, append a Slack node that sends a message (or uploads a file) to the desired Slack channel.

2. Send your webhook response immediately and then post to Slack.
   In your workflow, you might have a structure like:

   • Webhook → Respond to Webhook → Slack node

3. Include the screenshot as part of your Slack message.
   Since the screenshot is already saved in the n8n cloud (as binary data), you can either:

   • Use the Slack node’s upload capability (using Slack’s files.upload method) to attach the image to a channel message.
   • Or (if your Slack message allows rich formatting) include a reference to the image if it’s accessible via a public URL.

4. Example using the Slack node’s file upload operation:

Below is a simplified example of how the nodes could be configured in your workflow:

---

Webhook Node
(Triggers the workflow)

No special settings needed here beyond your usual webhook configuration.

---

Respond to Webhook Node
(Sends an immediate response back to the caller)

JSONCopied
{
	"responseCode": 200,
	"responseData": "Workflow has started, and your screenshot is being sent to Slack."
}

---

Slack Node (File Upload)
(Uploads the image saved as binary and posts a message)

Make sure the node is set with your Slack credentials, and in its parameters, use settings similar to the snippet below:

JSONCopied
{
  "resource": "file",
  "operation": "upload",
  "channel": "YOUR_SLACK_CHANNEL_ID",
  "fileName": "screenshot.png",
  "binaryPropertyName": "data",  // This should match the name of the binary property holding your screenshot
  "initial_comment": "Here is the screenshot from the workflow!",
  "title": "Workflow Screenshot"
}

Tip: If your screenshot is stored under a different binary property name (for example, screenshot), change "binaryPropertyName": "data" accordingly.

---

Workflow Overview:

1. Webhook Node: Receives the trigger and starts the workflow.
2. Respond to Webhook Node: Immediately sends the webhook response back.
3. Slack Node (File Upload): Uses the binary data from the saved screenshot to upload the file to the specified Slack channel, posting it along with a message.

---

Additional Notes:

• If you prefer to send a simple text message with an image reference rather than uploading the file, you can use the Slack node’s “Send Message” operation and provide a block or attachment with an image URL. This method works if the image is publicly accessible or you’ve previously uploaded it.
• Always verify that your Slack app has the proper scopes. For file uploads and message sending, at minimum, you need the relevant scopes for files.upload and chat.postMessage.

This approach lets you send the webhook response immediately while continuing the workflow to share your screenshot in Slack afterward.