How to fix Error: pg_config executable not found on Elastic Beanstalk permanently

Question

I have a Django project that works with PostgreSQL on Elastic Beanstalk. I have found the next error when deploying:

Error: pg_config executable not found.

pg_config is required to build psycopg2 from source. 

Please add the directory containing pg_config to the $PATH or specify the full executable path with the option:

python setup.py build_ext --pg-config /path/to/pg_config build ...

I followed psycopg2 on elastic beanstalk - can't deploy app to solve it and it worked! BUT after a while Amazon seems to update my virtual env and the error returns so I have to go back and do the same stuff over and over again.

I also have tried configuring the database instance directly from the Elastic Beanstalk panel but nothing changes.

The database is on RDS and I think it's important to say that when I manually install psycopg2 on my instance and re-deploy everything works fine, I even have made a couple of deploys after that and the problems is not there but it is after a while.

I really want to know how to solve it once for all. Thanks in advance.

Answer 1

It is trying to do is build the postgres drivers from source. You can deal with this several different ways. For example, you can choose to install the drivers from a binary package instead of building them from source.

in your requirements.txt, replace

psycopg2==2.8.5

with

psycopg2-binary==2.8.5

If, you do insist on building it from source when you deploy to Beanstalk, you will need to use platform hooks to pre-install the dependencies that are needed to compile it. The AL2 instances are pretty bare-bone, so you will need to do roughly the following:

• add directory structure .platform/hooks/prebuild
• in prebuild, create a script, something like '10_install_dependencies.sh'
• at the top of the script you will need #!/usr/bin/sh

Use this script to add needed dependencies. For example, for the posgres development libs you will want

sudo yum install -y <yum-packahe-that-you-need>

You may also end up having to install other development libs needed to build psycopg...