Support format version 2 for HTTP API's

[adamchainz]

https://docs.aws.amazon.com/apigateway/latest/developerguide/http-api-develop-integrations-lambda.html

Extended the example to deploy an HTTP API and dump its event, got one like this, plus error from trying to parse format version 1:

START RequestId: 863fef15-563d-498f-8d32-a4a5737f014f Version: $LATEST                                                                                                                                                                                                                                                                                                                                
{                                                                                                                                                                                                                                                                                                                                                                                                     
  "cookies": [                                                                                                                                                                                                                                                                                                                                                                                        
    "pN=7",                                                                                                                                                                                                                                                                                                                                                                                           
  ],                                                                                                                                                                                                                                                                                                                                                                                                  
  "headers": {                                                                                                                                                                                                                                                                                                                                                                                        
    "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",                                                                                                                                                                                                                                                                                                           
    "accept-encoding": "gzip, deflate, br",                                                                                                                                                                                                                                                                                                                                                           
    "accept-language": "en-GB,en;q=0.5",                                                                                                                                                                                                                                                                                                                                                              
    "content-length": "0",                                                                                                                                                                                                                                                                                                                                                                            
    "dnt": "1",                                                                                                                                                                                                                                                                                                                                                                                       
    "host": "s219lqqg4f.execute-api.eu-central-1.amazonaws.com",                                                                                                                                                                                                                                                                                                                                      
    "upgrade-insecure-requests": "1",                                                                                                                                                                                                                                                                                                                                                                 
    "user-agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:73.0) Gecko/20100101 Firefox/73.0",                                                                                                                                                                                                                                                                                               
    "x-amzn-trace-id": "Root=1-5e6b67ad-2d4a5560cf6fb7a02780c3a0",                                                                                                                                                                                                                                                                                                                                    
    "x-forwarded-for": "91.109.238.159",                                                                                                                                                                                                                                                                                                                                                              
    "x-forwarded-port": "443",                                                                                                                                                                                                                                                                                                                                                                        
    "x-forwarded-proto": "https"                                                                                                                                                                                                                                                                                                                                                                      
  },                                                                                                                                                                                                                                                                                                                                                                                                  
  "isBase64Encoded": true,                                                                                                                                                                                                                                                                                                                                                                            
  "rawPath": "/",                                                                                                                                                                                                                                                                                                                                                                                     
  "rawQueryString": "",                                                                                                                                                                                                                                                                                                                                                                               
  "requestContext": {                                                                                                                                                                                                                                                                                                                                                                                 
    "accountId": "931198139388",                                                                                                                                                                                                                                                                                                                                                                      
    "apiId": "s219lqqg4f",                                                                                                                                                                                                                                                                                                                                                                            
    "domainName": "s219lqqg4f.execute-api.eu-central-1.amazonaws.com",                                                                                                                                                                                                                                                                                                                                
    "domainPrefix": "s219lqqg4f",                                                                                                                                                                                                                                                                                                                                                                     
    "http": {                                                                                                                                                                                                                                                                                                                                                                                         
      "method": "GET",                                                                                                                                                                                                                                                                                                                                                                                
      "path": "/",                                                                                                                                                                                                                                                                                                                                                                                    
      "protocol": "HTTP/1.1",                                                                                                                                                                                                                                                                                                                                                                         
      "sourceIp": "91.109.238.159",                                                                                                                                                                                                                                                                                                                                                                   
      "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:73.0) Gecko/20100101 Firefox/73.0"                                                                                                                                                                                                                                                                                               
    },                                                                                                                                                                                                                                                                                                                                                                                                
    "requestId": "JU0jFiJxliAEJHg=",                                                                                                                                                                                                                                                                                                                                                                  
    "routeId": null,                                                                                                                                                                                                                                                                                                                                                                                  
    "routeKey": "$default",                                                                                                                                                                                                                                                                                                                                                                           
    "stage": "$default",                                                                                                                                                                                                                                                                                                                                                                              
    "time": "13/Mar/2020:10:59:57 +0000",                                                                                                                                                                                                                                                                                                                                                             
    "timeEpoch": 1584097197293                                                                                                                                                                                                                                                                                                                                                                        
  },                                                                                                                                                                                                                                                                                                                                                                                                  
  "routeKey": "$default",                                                                                                                                                                                                                                                                                                                                                                             
  "version": "2.0"                                                                                                                                                                                                                                                                                                                                                                                    
}                                                                                                                                                                                                                                                                                                                                                                                                     
[ERROR] KeyError: 'httpMethod' Traceback (most recent call last):   File "/var/task/testapp/wsgi.py", line 16, in lambda_handler     return apig_wsgi_handler(event, context)   File "/var/task/apig_wsgi.py", line 37, in handler     environ = get_environ(event, context, binary_support=binary_support)   File "/var/task/apig_wsgi.py", line 50, in get_environ     method = event["httpMethod"] 

[jmfederico]

Manually changing the payload to version 1 fixes the problem, do not know how to set that up with Ansible.

[adamchainz]

@jmfederico do you mean you swap "version" in the incoming event? That seems dangerous as there have been changes, and apgi-wsgi thus won't parse all the request data.

[jmfederico]

@adamchainz I mean changing the version that is sent to the Lambda function from the HttpAPI.

It by default now uses version 2. One has to manually set the API to send the event usi no version 1.

I do not use Ansible so I am not sure with the setup that you have which version it sends by default, but my guess is it sends version 2.

It should be possible to use Ansible to ser the version to 1.

[adamchainz]

Right, that can be changed in CloudFormation - docs . We don't have a AWS::ApiGatewayV2::Integration in the cfn template right now, so one would need adding to do that.

But I don't care about fixing the example app.

[irgeek]

You don't need to add a AWS::ApiGatewayV2::Integration resource -- there's a way to overriding certain configuration options for the managed HTTP API. If you add this to the template, it should switch the payload format.

  HttpApiOverrides:
    Type: AWS::ApiGatewayV2::ApiGatewayManagedOverrides
    Properties:
      ApiId: !Sub ${HttpApi}
      Integration:
        PayloadFormatVersion: 1.0

[mneil]

Thanks for writing this library. I've been using it on some lambdas and recently needed to switch to v2 to use the JWT authorizer. I think I can switch back to the v1 version, as suggested, but I'd really prefer to write less configuration if possible :). I think I added this functionality in #174 . I'm using this myself and would love to roll it back into your project so I can go back to including this from pypi. Let me know if you have any feedback or changes. Thanks again!