Unable to set up Scout APM on a Python AWS Lambda function

[krharsh17]

Hi,

I am trying to set up Scout APM monitoring for a dummy AWS Lambda function but it doesn't work as expected and throws the following error when the function is executed:

[ERROR] Runtime.ImportModuleError: Unable to import module 'lambda_function': cannot import name '_psutil_linux' from partially initialized module 'psutil' (most likely due to a circular import) (/var/task/psutil/__init__.py)
Traceback (most recent call last):

Following the instructions here, I have created and uploaded a deployment.zip to AWS Lambda that contains my code in the lambda_function.py file and the scout_apm package and its dependencies. Here's what the directory structure looks like:

The code used in the Lambda function is given below:

import json
import base64
# Import the Scout APM package
import scout_apm.api
import os

def lambda_handler(event, context):

    # Create a config object for initializing the Scout APM package
    config = {
        "name": "String to Base64",
        "key": os.environ['SCOUT_KEY'],
        "monitor": True,
    }
    
    # Initialize the Scout APM package
    scout_apm.api.install(config=config)

    # Start tracking a block of code as a transaction
    scout_apm.api.WebTransaction.start("Conversion")

    input_string = event["queryStringParameters"]["input"]
    
    b = base64.b64encode(bytes(input_string, 'utf-8'))
    base64_str = b.decode('utf-8')

    # Stop tracking the block of code 
    scout_apm.api.WebTransaction.stop()
    
    return {
        'statusCode': 200,
        'body': json.dumps(base64_str)
    }

I am passing the SCOUT_KEY value through AWS Lambda's environment variables and have verified that it is working. A weird thing I noticed about this is that if I set this up locally and try to run the lambda function using the python-lambda-local package, it works correctly and the Scout package is initialized too. Here's the output:

kumarharsh@Kumars-Macbook-Air string-to-base64 % SCOUT_KEY=my-scout-key-here python-lambda-local -f lambda_handler lambda_function.py event.json

[root - INFO - 2023-09-04 19:49:04,308] Event: {'queryStringParameters': {'input': 'hello world'}}
[root - INFO - 2023-09-04 19:49:04,308] START RequestId: cc868956-568a-4203-af7b-664399dbb9f3 Version: 
Scout draining 4 events for up to 2.0 seconds
[root - INFO - 2023-09-04 19:49:07,935] END RequestId: cc868956-568a-4203-af7b-664399dbb9f3
[root - INFO - 2023-09-04 19:49:07,936] REPORT RequestId: cc868956-568a-4203-af7b-664399dbb9f3  Duration: 1436.05 ms
[root - INFO - 2023-09-04 19:49:07,936] RESULT:
{'statusCode': 200, 'body': '"aGVsbG8gd29ybGQ="'}

But it just doesn't work when deployed to the actual AWS Lambda runtime. Here are the config values from my AWS Lambda function: Runtime: Python 3.11 Handler: lambda_function.lambda_handler Architecture: x86_64

I tried deleting the psutil package before zipping and uploading to Lambda but then the error changes to pustil not found. Please help me resolve this issue.