How to install Google or-tools on AWS Lambda? - amazon-web-services

Question

I've been successfully using Google's or-tools on AWS EC2 instances but have recently been looking into including them in AWS Lambda functions but can't get it to run.
Function debug.py
Below is just a basic function importing the pywrapcp from ortools which should succeed if everything is set up correctly.
from ortools.constraint_solver import pywrapcp
def handler(event, context):
print(pywrapcp)
if __name__ == '__main__':
handler(None, None)
Failing Module Import
I created a package.sh script that copies all dependencies to the project following Amazon's instructions before creating a zip archive. Running the deployed code results in this:
Unable to import module 'debug': No module named ortools.constraint_solver
Contents of package.sh
#!/bin/bash
DEST_DIR=$(dirname $(realpath -s $0));
echo "Copy all native libraries...";
mkdir -p ./lib && find $directory -type f -name "*.so" | xargs cp -t ./lib;
echo "Create package...";
zip -r dist.zip debug.py lib;
rm -r ./lib;
echo "Add dependencies from $VIRTUAL_ENV to $DEST_DIR/dist.zip";
cd $VIRTUAL_ENV/lib/python2.7/site-packages;
zip -ur $DEST_DIR/dist.zip ./** -x;
When I copy the ortools folder from ortools-4.4.3842-py2.7-linux-x86_64.egg directly into the project root it finds ortools but then fails to import pywrapcp which may be related to a failure loading the native libraries but I'm not sure since the logs don't show much detail.
Unable to import module 'debug': cannot import name pywrapcp
Any ideas?

Answer 1

Following the discussion on Google or-tools I put together a packaging script that works around the issues installing the dependencies in a way that works for AWS Lambda.
They key part of it is that the contents of the egg packages have to be copied manually to the Lambda project folder and been given the correct permission for them the be accessible during runtime.
#!/bin/sh
easy_install3 py3-ortools
find "/opt/python3/lib/python3.6/site-packages" -path "*.egg/*" -not -name "EGG-INFO" -maxdepth 2 -exec cp -r {} ./dist \;
chmod -R 755 ./dist
Instead of creating and configuring an EC2 instance, you can use Docker to create a deployable package locally, see or-tools-lambda for details.

Answer 2

Firstly, the underlying AWS Lambda execution environment is Amazon Linux while or-tools is not tested beyond the below environments as per https://github.com/google/or-tools
Ubuntu 14.04 and 16.04 up (64-bit).
Mac OS X El Capitan with Xcode 7.x (64 bit).
Microsoft Windows with Visual Studio 2013 and 2015 (64-bit)
Test your code by launching an instance with one of the ami's which aws lambda uses in the list here (http://docs.aws.amazon.com/lambda/latest/dg/current-supported-versions.html)
If it works, use pip to install dependencies/libraries at the root level of your project directory and then zip. Do not copy the libraries manually to your project directory