Websocket $connect route: headers and querystring empty on http integration

Question

I am using Websocket API that uses HTTP integration to communicate with my NodeJS Backend in EC2. I managed to pass on the _connectionId_ on the _$connect route_ using a Request Template.  
However when I do this, I am unable to pass on any custom header and querystring parameters. I have tried to pass these values using the Request Template by using the
 `$request.querystring`
 and the
 `$input.params`
 parameters. But this did not work.  
  
When the 'Use HTTP Proxy integration' is checked both the querystring and the custom headers are correctly passed on to the backend, but then the _connectionId_ is not passed on.  
  
My current Request Template is:

```
{
  "connectionId": "$context.connectionId",
  "domain": "$context.domainName",
  "stage": "$context.stage",
  "requestId": "$context.requestId",
  "body": "$input.body"
}
```

My question is, if it is possible to pass on querystring parameters/custom headers as well as the _connectionId_ in the _$connect route_ ?

Accepted Answer

At the time of writing, WebSocket API does not support query strings or headers in the template. You can take a look all supported variables here:  
https://docs.aws.amazon.com/apigateway/latest/developerguide/apigateway-websocket-api-mapping-template-reference.html  
  
I agree that it makes sense to support query strings/headers in the template for the $connect route while it does not for other routes. I'll create a backlog for this.

Websocket $connect route: headers and querystring empty on http integration

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