python-example-wrapper

Example Wrapper Script in Python

The provided code sample demonstrates how to get a wrapper script written in Python up and running.

There are two components to this sample:

• wrapper_script: This is a Python executable script that customizes the runtime startup by inserting additional parameters to the runtime process startup.
• lambda_function.py: This is a sample Python file that includes a Lambda function handler that validates and demonstrates the use of the extra arguments that were included by the wrapper script.

Customize the wrapper script

You can modify or include other valid runtime parameters in the script as extra arguments.

...
# the extra options we want to pass to the interpreter
extra_args = ["-X", "importtime"]
...

Modify that the script access permissions

You'll want to ensure that the script is executable by running the following command:

$ chmod +x wrapper_script

Deploy a function to test is out

Create a Lambda function for the Python runtime that includes both the wrapper_script and lambda_function.py using lambda_function.lambda_handler as the function handler.

Add an environment variable to your function's configuration with key AWS_LAMBDA_EXEC_WRAPPER and a value of /var/task/wrapper_script (if you've included the wrapper script alongside your function code).

Invoke the function

Invoke the function using a test eventand you should see the wrapper script in action reflected in the functions logs and invocation.