Generating credentials and configuring it on your Github Repo

[michael-dollosa]

Note: The Repo owner should be the one doing the steps below. Anyone who cloned the repo should not in any way push their master.key or credentials.yml.enc

To understand fully the issue, we must know how Github Actions works, and how was it setup in Rails. Below is a good place to start.

https://dev.to/abdellani/github-actions-to-run-rubocop-and-rspec-tests-on-rails-with-postgres-47i

Back to the issue, here is a sample snippet of the error.

# --- Caused by: ---
# ArgumentError:
#   key must be 16 bytes
#   ./vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.6/lib/active_support/message_encryptor.rb:193:in `key='

An error occurred while loading ./spec/helpers/users_helper_spec.rb.
Failure/Error: require File.expand_path('../config/environment', __dir__)

ActiveSupport::MessageEncryptor::InvalidMessage:
 ActiveSupport::MessageEncryptor::InvalidMessage
# ./vendor/bundle/ruby/2.7.0/gems/activesupport-6.0.3.6/lib/active_support/message_encryptor.rb:206:in `re`

There are 2 things that need to be considered:

1. Error is occurring because github actions cannot detect any key to decrypt your credentials.yml.enc
2. You do not have any secrets for your github actions to use.

Solving 1st issue

You need to generate your own master.key. This means that you need to also generate a new credentials.yml.enc.

1. To do that delete first credentials.yml.enc
2. On your console (be sure that you are inside your project directory), run EDITOR="code --wait" rails credentials:edit

This will generate master.key and a new credentials.yml.enc

3. Double check your gitignore and add master.key in it. YOU SHOULD NOT PUSH YOUR KEY FILE IN REPO. Only your encrypted file (credentials.yml.enc) should be pushed.

Solving 2nd issue

If you have read how to configure github action in rails, you will come across the step that the rails project should have a .yml file for github workflows. In the project folder, it is exactly rspec.yml

On this file, you will notice at around the end, that it uses RAILS_MASTER_KEY. RAILS_MASTER_KEY is an env variable where you store your master.key.

However, in this case, it was setup to read the configuration on your github repo settings (${{ secrets.RAILS_MASTER_KEY }}

So next step is to setup your key in your own repo. Go to your repo and click Settings -> Secrets.

Click New Repository Secret. It is important to note that the variable should be exactly the env variable on your rspec.yml - which is RAILS_MASTER_KEY.

Run your tests again and it should be done 💯