How can I authenticate my AWS Bedrock Nova Reels text-to-video model HTTP request in n8n?

Below is some insight into the issue you’re experiencing:

AWS Bedrock Model Node Support

Currently, the dedicated AWS Bedrock nodes provided by n8n (such as the AWS Bedrock Chat Model and Embeddings AWS Bedrock nodes) are built specifically for text-based operations. In your case, only text models appear because those are the ones supported by these nodes. The Nova Reels text-to-video model isn’t exposed via these nodes at this time.

AWS Signature Calculation

When you use an HTTP Request node directly with your AWS credentials, the request isn’t automatically signed using AWS Signature Version 4. The AWS Bedrock endpoints require that each request includes a properly calculated hash signature. Without this signing step, AWS will return a 403 Forbidden error with a message along the lines of “Forbidden - perhaps check your credentials?”

Workaround Options

1. Use the Dedicated Nodes:
   If your workflow can be adapted to the supported text models, it’s recommended to use the AWS Bedrock Chat Model node (or other relevant AWS Bedrock nodes) because these nodes handle authentication (including signature generation) automatically.

2. Manually Sign Requests:
   If you need to use a model that isn’t available in the dedicated nodes (such as Nova Reels), you’ll have to manually generate the AWS Signature Version 4 headers. This involves:

   • Calculating the canonical request.
   • Generating the string to sign.
   • Deriving the signature.
   • Attaching the appropriate Authorization header along with the other required headers.

   You can implement this signing process either:

   • In a Function node within your workflow.
   • By calling an external service that performs AWS SigV4 signing before you use the HTTP Request node.

Regarding “Share the output returned by the last node”

The “Forbidden - perhaps check your credentials?” error indicates that AWS is rejecting the request because the necessary signature isn’t present. When an HTTP Request node fails due to missing authentication details, its output typically includes the 403 status code and an error message similar to what you’re seeing. Since the node doesn’t complete a successful call, you won’t see any data beyond the error response.

Summary

• The dedicated AWS Bedrock nodes in n8n only support text models at this time.
• When using the HTTP Request node, AWS Signature Version 4 is not auto-calculated, resulting in the “Forbidden” error.
• For text-to-video (Nova Reels) or other non-text models, you’ll need to add custom logic to sign your requests or wait for a dedicated node that supports that model.

If you decide to implement your own SigV4 signing, you may refer to AWS documentation on AWS Signature Version 4 for the necessary details.

Hope this helps clarify the issue and points you in the right direction!