Invalid format in AccessLogSettings produced for websocket Api GW stage

[henhal]

Bug Report

Description

I have a websocket API gateway which has been deployed multiple times successfully. Now, all of a sudden the stack fails due to the Format of the AccessLogSettings in my AWS::ApiGatewayV2::Stage resource called WebsocketsDeploymentStage including $context.status which is not a valid context variable for websocket API:s, only REST API:s.
I don't know if this is due to a recent change in SLS or in AWS, but this API was deployed many times before without issues.

The following context variables are not supported: [$context.status] (Service: AmazonApiGatewayV2; Status Code: 400; Error Code: BadRequestException; Request ID: aa19bd81-9ef4-4182-89cd-29ae21d46fa1)

My serverless.yml file simply contains one or more functions with websocket events:

functions:
  MyWebSocketFunction:
    handler: websocket.handler
    events:
      - websocket:
          route: $connect 

This automatically causes SLS to create CF resources WebsocketsDeploymentStage etc:

  "WebsocketsDeploymentStage": {
      "Type": "AWS::ApiGatewayV2::Stage",
      "Properties": {
        "ApiId": {
          "Ref": "WebsocketsApi"
        },
        "DeploymentId": {
          "Ref": "WebsocketsDeployment1575366683940"
        },
        "StageName": "dev",
        "Description": "Serverless Websockets",
        "AccessLogSettings": {
          "DestinationArn": {
            "Fn::Sub": "arn:aws:logs:${AWS::Region}:${AWS::AccountId}:log-group:${WebsocketsLogGroup}"
          },
          "Format": "$context.identity.sourceIp $context.identity.caller $context.identity.user [$context.requestTime] \"$context.eventType $context.routeKey $context.connectionId\" $context.status $context.requestId"
        },
        "DefaultRouteSettings": {
          "DataTraceEnabled": true,
          "LoggingLevel": "INFO"
        }
      }
    },

I managed to temporarily resolve this by overriding the WebsocketsDeploymentStage resource to override the AccessLogSettings.Format property and remove $context.status from the value:

resources:
  Resources:
    ...
    WebsocketsDeploymentStage:
      # Overriding faulty format generated by SLS
      Properties:
        AccessLogSettings:
          Format: "$context.identity.sourceIp $context.identity.caller $context.identity.user [$context.requestTime] \"$context.eventType $context.routeKey $context.connectionId\" $context.requestId"

Then the stack was deployed just fine. But it seems like SLS is applying a default format string for the deployment stage which is not accepted by CF due to the use of the unsupported variable $context.status.

Similar or dependent issues:

[henhal]

Update: I checked the deployment we made about one week back and it also has the same $context.status format, but was accepted by AWS API Gateway. This makes me think that AWS changed something during the past few days, no longer accepting the $context.status property for websocket logs. If so, I assume SLS simply needs to adapt to this fact?

[henhal]

I went to find where this was located in the code and found that it was already fixed in d1537f7#diff-0b32a7aba4382097ae2219b301f674d2

When will this make it into a release?

[medikoo]

When will this make it into a release?

Sorry about delay. It'll be released first thing tomorrow CET morning.

[medikoo]

Closing as duplicate of #7016

[Gr8z]

I am still having this issue in 1.59

Logs:

Serverless: Packaging service...
Serverless: Excluding development dependencies...
Serverless: Uploading CloudFormation file to S3...
Serverless: Uploading artifacts...
Serverless: Uploading service BotBindSocketAPI.zip file to S3 (1.62 MB)...
Serverless: Validating template...
Serverless: Updating Stack...
Serverless: Checking Stack update progress...
...................
Serverless: Operation failed!
Serverless: View the full error output: https://us-east-1.console.aws.amazon.com/cloudformation/home?region=us-east-1#/stack/detail?stackId=arn%3Aaws%3Acloudformation%3Aus-east-1%3A093373140224%3Astack%2FBotBindSocketAPI-development%2F2c2e8cb0-edc1-11e9-b592-0eb40de15aba

  Serverless Error ---------------------------------------

  An error occurred: WebsocketsDeploymentStage - The following context variables are not supported: [$context.status] (Service: AmazonApiGatewayV2; Status Code: 400; Error Code: BadRequestException; Request ID: 56719d2c-f316-4835-86ac-15ea266e7af3).
 
  Get Support --------------------------------------------
     Docs:          docs.serverless.com
     Bugs:          github.com/serverless/serverless/issues
     Issues:        forum.serverless.com

  Your Environment Information ---------------------------
     Operating System:          win32
     Node Version:              10.15.2
     Framework Version:         1.59.0
     Plugin Version:            3.2.5
     SDK Version:               2.2.1
     Components Core Version:   1.1.2
     Components CLI Version:    1.4.0

[medikoo]

I am still having this issue in 1.59

Are you sure you're using CF template as generated by 1.59.0, and not e.g. one generated with older version ?

In v1.59.0, there's no mention of $context.status in part that handles Websocket logs -> https://github.com/serverless/serverless/blob/v1.59.0/lib/plugins/aws/package/compile/events/websockets/lib/stage.js#L62-L69