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Configuring Macbook for Ruby/Rails Development with automated scripts

Introduction

When you plan to do web development, you need to do few steps, like:

• installing installers (homebrew, rvm)
• installing support for various languages (ruby, java, nodejs, python, c, c++);
• installing databases (mysql, postgres, oracle etc);
• configuring databases (creating users, schemas, populating initial data);
• installing additional servers (apache, passenger, jenkins, selenium);
• starting/stopping services.

Usually all those steps are made manually. If it needs to be done only once, it’s OK. But next time when you try to reproduce all steps on new computer or explain new developer in the team, you can forget some details of it or forget completely what needs to be done.

As a common rule, it’s nice to have this information documented, or even better - automated in form of scripts.

There are numerous instructions around the Internet about how to configure your MacBook to work with Ruby and Rails. I have my own blog entry on the same topic. The problem with all of them is that they ought to be executed manually. But we want to do it automatically with the help of scripts.

When you try to solve this type of problem, you have “the chicken and the egg” problem - in order to do automatic provision, you have to have pre-installed languages/libraries. You don’t want to do everything in form of low-level shell script, but rather in high-level language, like ruby, python or node. Unfortunately such high-level scripts use external libraries that need to be downloaded and installed first before you can run scripts.

To make it simple and straightforward, we are going to do it remotely, e.g. you have one computer with pre-installed language and libraries and we will install all required programs over ssh on clean computer. It means that you have to enable ssh access on this computer. This idea is somewhat similar to what capistrano or chef does. Why don’t we use them here? Look at this article for the explanation.

I have built new ruby gem called osx_provision, that provides automated scripts for configuring Macbook. This article is about how to install, configure and use it with your project. Look at my previous article if you need to understand how to do it manually.

Install

Add this line to your application’s Gemfile:

gem 'osx_provision'

And then execute it:

bundle

Or install it yourself as:

gem install osx_provision

Configure

Before you can start using osx_provision gem within your project, you need to do the following:

• Create configuration file (e.g. .osx_provision.json) in json format at the root of your project. It will define your environment:

{
  "node": {
    "domain": "127.0.0.1",
    "user": "ENV['USER']",
    "home": "ENV['HOME']",
    "port": "",
    "remote": false
  },

  "project": {
    "home": "#{node.home}/work/my_project",
    "ruby_version": "1.9.3",
    "gemset": "new_gem"
  },

  "postgres": {
    "hostname": "localhost", "user": "postgres", "password": "postgres",
    "app_user": "pg_user", "app_password": "pg_password",
    "app_schemas": [ "my_project_test", "my_project_dev", "my_project_prod"]
  }
}

Variables defined in this file are used by underlying shell scripts provided by this gem. You can also add your own shell script (see details later) - in this case .osx_provision.json will have your variables as well.

Next node section describes your destination computer where you want to install this provision. In this example we do provisioning locally, but it’s possible to do it on remote machine, e.g.:

  ...
  "node": {
    "domain": "192.168.1.2",
    "user": "some_remote_user",
    "home": "some_remote_password",
    "port": "22",
    "remote": true
  },
  ...

In project section you keep project-related info, like project home, project gemset name and ruby version.

If you need to refer variable form another section, use “dot” notation, like #{node.home}. It is possible thanks to another gem called text-interpolator.

Last postgres section contains information about your postgres server and what database user and schemas need to be created. In our example we describe that we want to create pg_user with password and 3 schemas: my_project_test, my_project_dev, my_project_prod. Postgres server itself is located at localhost address.

You can also add mysql section - it’s also supported.

• Provide execution script

Library itself if written in ruby, but for launching its code you have to use rake or thor tool. Here I provide thor script as an example:

# thor/osx_install.thor

$: << File.expand_path(File.dirname(__FILE__) + '/../lib')

require 'osx_provision'

class OsxInstall < Thor
  @installer = OsxProvision.new self, ".osx_provision.json"

  class << self
    attr_reader :installer
  end

  desc "all", "Installs all required packages"
  def all
    invoke :brew # execute command defined in shell script
    invoke :rvm
    invoke :qt

    invoke :init_launch_agent

    invoke :postgres
    invoke :postgres_restart

    invoke :jenkins
    invoke :jenkins_restart

    invoke :selenium

    invoke :ruby

    invoke :postgres_create_user
    invoke :postgres_create_schemas
  end

  desc "postgres_create_schemas", "Initializes postgres schemas"
  def postgres_create_schemas
    # execute method from  OsxProvision class - we need to read
    # schema names from configuration file and create them in the loop
    OsxInstall.installer.postgres_create_schemas
  end

  desc "postgres_drop_schemas", "Drops postgres schemas"
  def postgres_drop_schemas
    OsxInstall.installer.postgres_drop_schemas
  end
end

You can execute separate commands from script directly with invoke thor command. Below is fragment of such script:

#!/bin/sh

[prepare]

mkdir #{home}/Library/LaunchAgents/

[brew]

ruby -e "$(curl -fsSL https://raw.github.com/Homebrew/homebrew/go/install)"

brew update
brew doctor

brew tap homebrew/dupes
brew tap homebrew/versions

[rvm]

PATH=$PATH:/usr/local/bin
USER_HOME="#{node.home}"

curl -L https://get.rvm.io | bash

source $USER_HOME/.rvm/scripts/rvm

All available scripts are located here. If you need more scripts, you can create them locally (e.g. in (thor/osx_provision_scripts_my_project.sh)) and then initialize thor script accordingly:

# thor/my_project_osx_provision_scripts.thor
...

class OsxInstall < Thor
  @installer = OsxProvision.new self, ".osx_provision.json",
                 [File.expand_path("my_project_osx_provision_scripts.sh", File.dirname(__FILE__))]
  ...
end

Below is the example of such script for running rails server in standard and debug mode:

#!/bin/sh

##############################
[rails]

USER_HOME="#{node.home}"
APP_HOME="#{project.home}"

cd $APP_HOME

source $USER_HOME/.rvm/scripts/rvm

rvm use #{project.ruby_version}@#{project.gemset} --create

bundle exec rails s

##############################
[rails_debug]

USER_HOME="#{node.home}"
APP_HOME="#{project.home}"

cd $APP_HOME

source $USER_HOME/.rvm/scripts/rvm

rvm use #{project.ruby_version}@#{project.gemset} --create

RAILS=`which rails`

bundle exec rdebug-ide --port 1234 --dispatcher-port 26162 -- $RAILS s

Executing automated scripts

First, take a look at the list of available thor command:

thor -T

You can see something like this:

osx_install
-----------
thor osx_install:all                      # Installs all required packages
thor osx_install:app                      # Installs app
thor osx_install:brew                     # brew
thor osx_install:general                  # Installs general packages
thor osx_install:git                      # git
thor osx_install:jenkins                  # jenkins
thor osx_install:jenkins_restart          # jenkins_restart
thor osx_install:mysql                    # mysql
thor osx_install:mysql_create_schema      # mysql_create_schema
thor osx_install:mysql_create_schemas     # Initializes mysql schemas
thor osx_install:mysql_create_user        # mysql_create_user
thor osx_install:mysql_drop_schema        # mysql_drop_schema
thor osx_install:mysql_drop_schemas       # Drops mysql schemas
thor osx_install:mysql_drop_user          # mysql_drop_user
thor osx_install:mysql_restart            # mysql_restart
thor osx_install:npm                      # npm
thor osx_install:package_installed        # package_installed
thor osx_install:postgres                 # postgres
thor osx_install:postgres_create_schema   # postgres_create_schema
thor osx_install:postgres_create_schemas  # Initializes postgres schemas
thor osx_install:postgres_create_user     # postgres_create_user
thor osx_install:postgres_drop_schema     # postgres_drop_schema
thor osx_install:postgres_drop_schemas    # Drops postgres schemas
thor osx_install:postgres_drop_user       # postgres_drop_user
thor osx_install:postgres_restart         # postgres_restart
thor osx_install:postgres_start           # postgres_start
thor osx_install:postgres_stop            # postgres_stop
thor osx_install:prepare                  # prepare
thor osx_install:qt                       # qt
thor osx_install:ruby                     # ruby
thor osx_install:rvm                      # rvm
thor osx_install:selenium                 # selenium
thor osx_install:selenium_restart         # selenium_restart
thor osx_install:service_started          # service_started
thor osx_install:svn                      # svn

With this scripts you can execute them separately and all together:

thor osx_install:brew
thor osx_install:rvm
thor osx_install:postgres
thor osx_install:brew

thor osx_install:all

To configure postgres only run this sequence:

thor osx_install:postgres
thor osx_install:postgres_create_user
thor osx_install:postgres_create_schemas
thor osx_install:postgres_start

Enjoy the gem and let me know if other useful command can be added to it.