joakimk

echo -e "machine api.heroku.com\n  login $HEROKU_USER\n  password $HEROKU_API_KEY\nmachine code.heroku.com\n  login $HEROKU_USER\n  password $HEROKU_API_KEY" > ~/.netrc && chmod 0600 /home/ubuntu/.netrc # We want to simply configure the API key, this seems easier than using the regular UI as that requires you to log in as a github user and assign yourself, etc.

joakimk

This runs a build for a small elixir (phoenix) project in about 40 seconds by caching as much of the compiled files as possible.

We've been using this for months in multiple projects without any issues. Please ping be if there is any issues with this script and I'll update it.

It should be generic enough to work on any elixir app using mix.

If you have a elixir_buildpack.config, then enable that section in the build script to keep versions in sync!

2016-08-09: Updated to newer Erlang and Elixir and fixed curl command.

joakimk

Code.require_file "support/test_redis.exs", __DIR__
ExUnit.start
TestRedis.start

joakimk

I just read http://re-factor.com/blog/2013/09/27/slow-tests-are-the-symptom-not-the-cause/.

I fully agree that the testing speed can often be a result of improving the code design.

This is probably how I'd implement a similar feature in barsoom.se's apps.

I'm mostly of the opinion that you should use the right tool for each job. Integrated tests to test integration. Unit tests to test logic and message passing.

I prefer to keep things simple and avoid dependency injection until there is a need for it outside of tests.

joakimk

require "minimapper/mapper"

class ApplicationMapper < Minimapper::Mapper
  def record_class
    record_name = self.class.name.gsub(/Mapper/, "Record")
    record_name.constantize
  end
end

joakimk

require "active_record"

# Also highly recommended:
# require "active_support/dependencies"
# ActiveSupport::Dependencies.autoload_paths += [ "app/models" ]
# ..so you don't need to do manual requires, found it to be just as fast.

# Support unit testing AR models without loading all of rails.
connection_info = YAML.load(ERB.new(File.read("config/database.yml")).result)["test"]
ActiveRecord::Base.establish_connection(connection_info)

joakimk

Using ActiveSupport::Dependencies outside of rails seems just as fast as doing manual requires. I've found this out by replacing hundreds of requires in a unit tested code base with ActiveSupport::Dependencies without any change to the time it takes to run the test suite.

Using ActiveSupport::Dependencies also allows you to have circular depedencies like class Foo::Bar in foo/bar.rb and class Foo in foo.rb that points to Foo::Bar in it's class definition (like in a rails validation).

The classical way of solving this without ActiveSupport::Dependencies is to do:

# foo/bar.rb
class Foo
 class Bar

joakimk

# Functional core
# Tested with unit tests. Mostly simple state based tests (like: invoice.gross_amount.should == 200).
class BuildInvoice
  def build
    # build invoice in memory..
  end
end

# Imperative shell
# Usually just tested with a single test to ensure it stores data in the database

joakimk

http://privpakportal.schenker.nu/TrackAndTrace/packageinfo.aspx?packagesurrid=69682901&inpPackageId=<SSCC NO>

joakimk

Association loading

# Load data from the DB
user = user_mapper.find(params[:id], include: { profile: :group })

# Use data in memory (you can't do lazy-loads with minimapper, which is probably
# a very good thing. Lets you avoid N+1 by default).
user.profile.group.name