AWS API Gateway base64Decode produces garbled binary?

Question

I\'m trying to return a 1px gif from an AWS API Gateway method.

Since binary data is now supported, I return an image/gif using the following \'Integration Response\

Answer 1

It looks like this was a known issue previously: https://forums.aws.amazon.com/thread.jspa?messageID=668306򣊒

But it should be possible now that they've added support for binary data: http://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-payload-encodings.html

It looks like this is the bit we need: "Set the contentHandling property of the IntegrationResponse resource to CONVERT_TO_BINARY to have the response payload converted from a Base64-encoded string to its binary blob". Then we shouldn't need the base64Decode() function.

Working on a test now to see if this works.

EDIT: I was finally able to get this working. You can see the binary image here: https://chtskiuz10.execute-api.us-east-1.amazonaws.com/prod/rest/image

Here's my Lambda function that returns the base64 encoded PNG as a string: https://gist.github.com/davemaple/73ce3c2c69d5310331395a0210069263

I updated the method response as follows:

I updated the integration response to include a hard-coded image/png header:

The last step was tricky: setting the contentHandling property to "CONVERT_TO_BINARY". I couldn't figure out how to do in the AWS console. I had to use the CLI API to accomplish this:

aws apigateway update-integration-response \
    --profile davemaple \
    --rest-api-id chtskiuzxx \
    --resource-id ki1lxx \
    --http-method GET \
    --status-code 200 \
    --patch-operations '[{"op" : "replace", "path" : "/contentHandling", "value" : "CONVERT_TO_BINARY"}]'

I hope this helps.