Rails 4: PG::InFailedSqlTransaction when testing a rake task with RSpec - ruby-on-rails

Question

I am currently trying to test a rake task with RSpec.
My Rails version is 4.2.4 and rspec-rails version is 3.3.2.
I've have the following in rails_helper.rb:
ENV['RAILS_ENV'] ||= 'test'
require 'spec_helper'
require File.expand_path('../../config/environment', __FILE__)
require 'rspec/rails'
require 'capybara/rspec'
Dir[Rails.root.join('spec/support/**/*.rb')].each { |f| require f }
RSpec.configure do |config|
...
config.use_transactional_fixtures = false
config.infer_spec_type_from_file_location!
...
end
and then spec/support/tasks.rb:
require 'rake'
module TaskExampleGroup
extend ActiveSupport::Concern
included do
let(:task_name) { self.class.top_level_description.sub(/\Arake /, "") }
let(:tasks) { Rake::Task }
# Make the Rake task available as `task` in your examples:
subject(:task) { tasks[task_name] }
end
end
RSpec.configure do |config|
# Tag Rake specs with `:task` metadata or put them in the spec/tasks dir
config.define_derived_metadata(file_path: %r{/spec/tasks/}) do |metadata|
metadata[:type] = :task
end
config.include TaskExampleGroup, type: :task
config.before(:suite) do
Rails.application.load_tasks
end
end
my spec/support/database_cleaner.rb
RSpec.configure do |config|
config.before(:suite) do
DatabaseCleaner.clean_with(:truncation)
end
config.before(:each) do
DatabaseCleaner.strategy = :transaction
end
config.before(:each, js: true) do
DatabaseCleaner.strategy = :truncation
end
config.before(:each) do
DatabaseCleaner.start
end
config.append_after(:each) do
DatabaseCleaner.clean
end
end
and finally, the spec:
require 'rails_helper'
describe "rake some:my_task", type: :task do
# This test passes
it 'preloads the Rails environment' do
expect(task.prerequisites).to include 'environment'
end
# This test fails
it 'creates AnotherModel' do
my_hash = {foo => 'bar'}
allow(MyClient::Event).to receive(:list).and_return(my_hash)
expect { task.execute }.not_to raise_error
expect(AnotherModel.count).to eq(1)
end
end
The problem is that for some reason, executing this code results in the following error:
Failure/Error: AnotherModel.count
ActiveRecord::StatementInvalid:
PG::InFailedSqlTransaction: ERROR: current transaction is aborted, commands ignored until end of transaction block
The rake task looks like this:
namespace :some do
desc 'Parse stream'
task my_task: :environment do |_t|
cint_events['events'].each do |event|
begin
events = MyClient::Event.list(some_hash)
events.each do |event|
if some_condition
# The test should check whether this object gets created
AnotherModel.first_or_create_by(foo: some_hash['foo'])
end
end
rescue => e
# Log errors
end
end
end
end
I've tried running:
RAILS_ENV=test rake db:drop db:create db:migrate
and then running the spec again but I keep getting the aforementioned error. What might this be caused by?
Thanks in advance!

Answer 1

You configured your tests to run in a database transaction, which is a good thing.
But within your rake task you just eat up all errors that appear with:
rescue => e
# Log errors
end
However, certain errors may still cause you transaction to fail and rollback. So my guess is, that some severe error is happening the first time you do a call to the database (For example, the column foo is not known to the database). After that, it catches the error and you are adding a statement (AnotherModel.count) to the already aborted transaction, which fails.
So a good place to start is to check what the value of e.message is in your rescue block.
Also note:
It is never a good idea to rescue all errors blindly, and almost always leads to strange and unexpected behaviours.

Answer 2

This error seems to occur when in a test environment and your SQL query via ActiveRecord doesn't recognize a field in your query. In other words you have a scope or are trying to return some ActiveRecord relation with a bad database column name.
See this related post:
ActiveRecord::StatementInvalid: PG InFailedSqlTransaction