doc: Add test instructions (#136)

* Add test instructions

* Use env var in more places

---------

Co-authored-by: João Esteves <joao.esteves@jumpseller.com>

Author: joao-esteves

README.md

@@ -147,6 +147,16 @@ concurrent access to **any instance of a model**. Their coarseness means they
 aren't going to be commonly applicable, and they can be a source of
 [deadlocks](http://en.wikipedia.org/wiki/Deadlock).
 
+## Running Tests
+
+To setup the project and run the whole test suite:
+
+1. Have Docker running
+2. `echo -e "DB_USER=with_advisory\nDB_PASSWORD=with_advisory_pass\nDB_NAME=with_advisory_lock_test\nDATABASE_URL_PG=postgres://\$DB_USER:\$DB_PASSWORD@localhost:5433/\$DB_NAME\nDATABASE_URL_MYSQL=mysql2://\$DB_USER:\$DB_PASSWORD@127.0.0.1:3366/\$DB_NAME" > .env`
+3. `make`
+
+Alternatively to `make`, run `bin/rails test` to skip database and dependency setup.
+
 ## FAQ
 
 ### Transactions and Advisory Locks

bin/setup_test_db

@@ -3,16 +3,18 @@
 
 require 'bundler/setup'
 require 'active_record'
+require 'dotenv'
+Dotenv.load
 
 # Setup PostgreSQL database
 puts 'Setting up PostgreSQL test database...'
 ActiveRecord::Base.establish_connection(
   adapter: 'postgresql',
   host: 'localhost',
   port: 5433,
-  database: 'with_advisory_lock_test',
-  username: 'with_advisory',
-  password: 'with_advisory_pass'
+  database: ENV['DB_NAME'],
+  username: ENV['DB_USER'],
+  password: ENV['DB_PASSWORD']
 )
 
 ActiveRecord::Schema.define(version: 1) do
@@ -36,9 +38,9 @@ ActiveRecord::Base.establish_connection(
   adapter: 'mysql2',
   host: '127.0.0.1',
   port: 3366,
-  database: 'with_advisory_lock_test',
-  username: 'with_advisory',
-  password: 'with_advisory_pass'
+  database: ENV['DB_NAME'],
+  username: ENV['DB_USER'],
+  password: ENV['DB_PASSWORD']
 )
 
 ActiveRecord::Schema.define(version: 1) do

docker-compose.yml

@@ -2,17 +2,17 @@ services:
   pg:
     image: postgres:17-alpine
     environment:
-      POSTGRES_USER: with_advisory
-      POSTGRES_PASSWORD: with_advisory_pass
-      POSTGRES_DB: with_advisory_lock_test
+      POSTGRES_USER: ${DB_USER}
+      POSTGRES_PASSWORD: ${DB_PASSWORD}
+      POSTGRES_DB: ${DB_NAME}
     ports:
       - "5433:5432"
   mysql:
     image: mysql:8
     environment:
-      MYSQL_USER: with_advisory
-      MYSQL_PASSWORD: with_advisory_pass
-      MYSQL_DATABASE: with_advisory_lock_test
+      MYSQL_USER: ${DB_USER}
+      MYSQL_PASSWORD: ${DB_PASSWORD}
+      MYSQL_DATABASE: ${DB_NAME}
       MYSQL_RANDOM_ROOT_PASSWORD: "yes"
       MYSQL_ROOT_HOST: '%'
     ports: