使用 AWS 网关 API 代理从 Python AWS Lambda 重定向

Question

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Browser just returns json still

Posting here because I just can't get a redirect working. Using AWS API Gateway linked to a Python Lambda function as a proxy just returns the response and header json. Here is the code

import json

def lambda_handler(event, context):
    response = {}
    response["statusCode"]=301
    response["headers"]=[{"key": 'Location',"value": 
     'https://www.google.com'}]
    data = {}
    response["body"]=json.dumps(data)
return response

Any help will be appreciated?

Thanks

Answer 1

Mixed documentation on the web which was confusing. The syntax for specifying the redirect using Location needs to be the following when using Python:

import json

def lambda_handler(event, context):   
    response = {}
    response["statusCode"]=302
    response["headers"]={'Location': 'https://www.google.com'}
    data = {}
    response["body"]=json.dumps(data)
    return response

Answer 2

a bit less line, with the same output

def handler(event, context):
    response = {
        "headers": {"Location": "https://www.google.com", },
        "statusCode": 301,
    }

    return response

Answer 3

I'll prefix this by saying that when I copied this code into a Lambda function, added an API Gateway to it using the settings that made sense to me, and tested from a browser and curl, I got the correct redirect. Which is expected, the code looks right and conforms to the specification in the documentation.

So I spent some time fiddling with settings in Lambda and in API Gateway to try to break it; plus Googling around to see how others have had it not work.

The general Inte.net consensus in 2021 (time of original post) is that there was a setting "Use Lambda proxy integration" in the API Gateway that needed to be turned on for API Gateway to interpret the returned JSON correctly, and this was not the default. I can't find that setting in the console today in that format, but when you create an API Gateway "API" you select integrations, the first one in the list is Lambda. Selecting that sets up the integration correctly for interpreting the JSON (in either v1 or v2 format).

If you are working in an older already-configured API Gateway endpoint, I'd suggest looking for the "Use Lambda proxy integration" setting, followed by setting up the API Gateway with the "Lambda" integration setting if it is the new-style interface.

If anyone is experiencing this issue right now (I presume so, since there is a current bounty on the question) then comment or update with details of how your API Gateway is set up, and I might be able to point you at where it differs.