AWS API Gateway: Log Query String in Access Log

Question

I've enabled Access Logging to CloudWatch for my API in AWS API Gateway and that works fine. However, it will only log the path section of the URL and not my query string parameters.

My log format looks like this:

[$context.requestTime] ($context.status) "$context.httpMethod $context.path $context.requestId

Let's say, I call my API like this:

GET http://my.server.com/details?id=123

The corresponding access log line will look like this:

[19/Jun/2018:06:09:27 +0000] (200) "GET /details 5229a43c-7387-11e8-xxxx-xxxxxxxx

I need the id=123 as well, but I can't figure out how to access it. The documentation suggest using $input.params('id'), but that will always return -.

Same, $input.params() also returns -. I tried all variations of it that I found. — Phil
– Phil, Commented Jun 19, 2018 at 7:20
Are you trying to invoke in console or with aws cli? There were some issues with params if you run it from console. — GiorgosDev
– GiorgosDev, Commented Jun 19, 2018 at 9:11
I'm setting this in the AWS Console. It's saving correctly, no error messages. — Phil
– Phil, Commented Jun 20, 2018 at 0:41
it seems there is no support for $input variables for custom access logging. forums.aws.amazon.com/thread.jspa?messageID=860814&tstart=0 — hoonoh
– hoonoh, Commented Aug 22, 2018 at 7:50

Andres Luque · Accepted Answer · 2020-01-24 21:40:40Z

5

Only $context variables are supported, not $input, etc. AWS Ref: Have you seen https://docs.aws.amazon.com/apigateway/latest/developerguide/set-up-logging.html?

answered Jan 24, 2020 at 21:40

Andres Luque

551 silver badge4 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

surry · Accepted Answer · 2023-08-17 00:21:39Z

0

I have not been able to figure out a way to log the query string other than to integrate it within my Lambda Authorizer. This is a code snippet. You then reference the query string in the access log format definition as "queryString": "$context.authorizer.queryString"

def lambda_handler(event, context):
    queryStringParameters = event["queryStringParameters"]
    queryString = urlencode(queryStringParameters)
    authResponse = {
        "principalId": "",
        "policyDocument": {
            "Version": "",
            "Statement": []
        }
    }
    
    authResponse["principalId"] = "user|a1b2c3d4"
    authResponse["policyDocument"]["Version"] = "2012-10-17"
    authResponse["policyDocument"]["Statement"] = []
    statementOne = {
        "Action": "execute-api:Invoke",
        "Effect": effect,
        "Resource": methodArn
    }
    authResponse["policyDocument"]["Statement"].append(statementOne)
    context = {
        'queryString': queryString
    }
    authResponse['context'] = context
    return authResponse

edited Aug 17, 2023 at 0:21

answered Aug 17, 2023 at 0:17

surry

11 bronze badge

1 Comment

user64204 Over a year ago

That's unusable, because authorizer response is cached. I.e. you will get old queryString.

Collectives™ on Stack Overflow

AWS API Gateway: Log Query String in Access Log

2 Answers 2

Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related