Creating an AWS Lambda Layer using CloudShell
Using python packages from
pip is a bit nontrivial on AWS Lambda. The solution is to use Lambda Layers, which act like virtual environments. Creating a layer programatically isn’t straightforward, but it can be done.
A layer can be created by zipping packages downloaded from
pip, but they must be compiled for use on Amazon Linux. One simple way to do that without spinning up an EC2 instance is with AWS CloudShell.
virtualenv must be installed on the CloudShell environment.
sudo pip install virtualenv
pip install yields an error
PermissionError: [Errno 13] Permission denied: '/usr/local/lib64/python3.7/site-packages/...'. Not sure why.
It’s also a good idea to set
alias pip=pip3. Somehow this isn’t the default on CloudShell.
Given a file
requirements.txt, the script below can be run on CloudShell to produce a
layer.zip file that is sufficient for Python 3.7, the installed Python version on CloudShell at the time of writing.
virtualenv ve source ve/bin/activate pip install -r requirements.txt mkdir -p tmp/python cp -rp ve/lib/python3.7/site-packages/* tmp/python cp -rp ve/lib64/python3.7/site-packages/* tmp/python pushd tmp pushd python rm -r *.dist-info *.virtualenv popd zip -r9 -q ../layer.zip python popd rm -r tmp ve