Spawn fewer services for Multiple database ruby gem tests

Background

I have a few ruby gems that run tests for a few databases. They all follow the same pattern.

Now

I start up mysql and postgres services for all test matrix entries.

Request

I would like to find a way to only run the services that I need.

using service works for mysql and postgres. using systemctl works for mysql but not for postgres.

Anyone with an idea how I can only spawn the necessary service?

Thanks for the great service,
Keenan

Current

---
sudo: false
language: ruby
cache: bundler

rvm:
  - 2.5.5

services:
  - mysql
  - postgresql

env:
  - DB=mysql2
  - DB=pg
  - DB=sqlite3

gemfile:
  - gemfiles/gemfile_50.gemfile
  - gemfiles/gemfile_51.gemfile
  - gemfiles/gemfile_52.gemfile
  - gemfiles/gemfile_60.gemfile

before_script:
  - [ $DB = "mysql2" ] && mysql -e 'create database hash_options_test;' || true
  - [ $DB = "pg" ] && psql -c 'create database hash_options_test;' -U postgres || true

Failure A

The current travis scripts call the command travis_setup_postgresql && postgresql@9.6-main but they are not availble to me from before_script1. I would like to use what ever is defined in the services: list.

---
sudo: false
language: ruby
cache: bundler

rvm:
  - 2.5.3

env:
  - DB=mysql2
  - DB=pg
  - DB=sqlite3

gemfile:
  - gemfiles/gemfile_50.gemfile
  - gemfiles/gemfile_51.gemfile
  - gemfiles/gemfile_52.gemfile
  - gemfiles/gemfile_60.gemfile

before_script:
  - sh -c "[ '$DB' = 'mysql2' ] && sudo systemctl start mysql && mysql -e 'create database hash_options_test;' || true"
  - sh -c "[ '$DB' = 'pg' ] && sudo systemctl start postgresql && psql -c 'create database hash_options_test;' -U postgres || true"

Failure 2

Tried to get services linked into the test matrix. under the env: section seems to make the most sense to me.

---
sudo: false
language: ruby
cache: bundler

rvm:
  - 2.5.3

env:
  - DB=mysql2
    services: mysql
  - DB=pg
    services: postgres
  - DB=sqlite3

gemfile:
  - gemfiles/gemfile_50.gemfile
  - gemfiles/gemfile_51.gemfile
  - gemfiles/gemfile_52.gemfile
  - gemfiles/gemfile_60.gemfile

before_script:
  - sh -c "[ '$DB' = 'mysql2' ] &&  mysql -e 'create database hash_options_test;' || true"
  - sh -c "[ '$DB' = 'pg' ] && psql -c 'create database hash_options_test;' -U postgres || true"

Have you had a peek at this?

@Montana Thanks for replying

I followed the instructions for using-environment variables. https://docs.travis-ci.com/user/database-setup/#using-environment-variables-and-a-before_script-step

But there isn’t a way to limit the services running for each variable.
I’ll read through that again. it has provided nuggets of information in the past.