Meso Backend

A Rails API and system administration dashboard for the Meso platform

Environment setup

Homebrew is recommended for installing dependencies.

direnv and the .envrc file is used to automatically load and unload environment variables when switching into and out of the current directory. Install it via:

$ brew install direnv
$ echo 'eval "$(direnv hook bash)"' >> ~/.bash_profile # or echo 'eval "$(direnv hook $SHELL)"' >> ~/.zshrc if you use zsh
$ exec $0
$ direnv allow .

The app expects the following libraries to be installed, all available via Homebrew:

heroku - the Heroku toolbelt helps with emulating our deployment environment locally as well as managing our Heroku apps.
imagemagick - used by Dragonfly to manipulate images.

Ruby setup

We're currently running on Ruby 2.6 and Rails 5.1.

Install and manage Ruby versions with rvm. Make sure to install the correct Ruby version, which is specified in the Gemfile, in addition to above. No gemset is specified for this project.

Database setup

We're currently running PostgreSQL 9.6.9.

Note that Homebrew will always install the latest version of software available, so when you install PostgreSQL you might be getting a later version of PostgreSQL than what is run in production. There is a way around this, but we haven't seen any serious problems with this mismatch of local and production environments, yet.

Install and start PostgreSQL with:

$ brew install postgresql
$ brew services start postgresql

Create a general postgres database user with CREATEDB and SUPERUSER privileges using the createuser command:

$ createuser -s -d postgres

Finally, initialize your database for the project. The development and test databases will be created and set up with the schema, and the development database seeded with default data from scripts/demo/generate_demo_data.rb.

$ rails db:setup #(or rails db:create db:migrate)
$ rails db:seed:demo_data

You can always start an interactive psql terminal into your development database with $ psql meso_backend_development.

Local development

Running the server locally

With the environment, ruby, and the database set up, you can start up the app with just rails s -p 5000. This starts up the API at http://localhost:5000/.

Running tests

We use Rspec for tests. To run all the specs: rspec. To run a specific file, run rspec <file name>. To run a specific test case, run rspec <path-to-file>:<line-number>

Console access

rails console

This gets you access to all data via rails and useful for debugging purposes. I.e. if you enrolled a member and want to verify that it has synced to the backend, in rails console you can do Member.order('created_at').last to confirm.

On all environments (including development), opening a Rails console requires declaring who you are – that is, entering the username of an admin user. This is not a form of authentication, since the ability to open a Rails console requires unfettered access to the deployed environment (including database backups, etc). The user declaration merely allows for tracking who made what changes and eases future data spelunking.

CI/CD

Continuous Integration: Every branch and every commit, once pushed to the GitHub repo, will run its specs automatically on CircleCI.

Logging

For logs emitted by Rails, we use the lograge gem to only log one line per request. The line contains details about the request formatted in Heroku-style, key=value output for easy parsing. Here's an example log entry:

Mar 2 12:55:35 meso app[web] at=info source=app method=GET path="/providers/1/billables" request_id=1bf1afb9-15da-46e8-b9c8-73dd238a00fd format=html controller=BillablesController action=index status=304 duration=18.14ms view=0.0ms db=0.0ms

jbeorse/meso-backend