Fake SQS

Inspired by [Fake DynamoDB] fake_dynamo, this is an AWS SQS compatible message queue that can be ran locally. This makes it ideal for integration testing, just like you would have a local database running. Fake SQS doesn't persist anything, not even the queues themselves. You'll have to create the queues everytime you start it.

This implementation is not complete yet, but should be useful already.

Done so far are:

• Creating queues
• Deleting queues
• Listing queues (with prefixes)
• Get queue url via the name
• Send messages (and in batch)
• Receive messages (and in batch)
• Deleting messages (and in batch)
• Changing queue attributes (but not all, and no validation)
• Setting visibility timeouts for messages

Certain bits are left off on purpose, to make it easier to work with, such as:

• No checking on access keys or signatures
• No 60 second delay between deleting a queue and recreating it.

Other parts are just not done yet:

• Permissions
• Error handling

So, actually, just the basics are implemented at this point.

PS. There is also [Fake SNS] fake_sns.

Usage

To install:

$ gem install fake_sqs

To start:

$ fake_sqs

To configure, see the options in the help:

$ fake_sqs --help

By default, FakeSQS uses an in-memory database (just a hash actually). To make it persistant, run with:

$ fake_sqs --database /path/to/database.yml

Messages are not persisted, just the queues.

This is an example of how to configure the official [aws-sdk gem] aws-sdk, to let it talk to Fake SQS.

AWS.config(
  :use_ssl           => false,
  :sqs_endpoint      => "localhost",
  :sqs_port          => 4568,
  :access_key_id     => "access key id",
  :secret_access_key => "secret access key"
)

If you have the configuration options for other libraries, please give them to me.

To reset the entire server, during tests for example, send a DELETE request to the server. For example:

$ curl -X DELETE http://localhost:4568/

Within SQS, after receiving, messages will be available again automatically after a certain time. While this is not implemented (for now at least), you can trigger this behavior at at will, with a PUT request.

$ curl -X PUT http://localhost:4568/

Test Integration

When making integration tests for your app, you can easily include Fake SQS.

Here are the methods you need to run FakeSQS programmatically.

require "fake_sqs/test_integration"

# globally, before the test suite starts:
AWS.config(
  use_ssl:            false,
  sqs_endpoint:       "localhost",
  sqs_port:           4568,
  access_key_id:      "fake access key",
  secret_access_key:  "fake secret key",
)
fake_sqs = FakeSQS::TestIntegration.new

# before each test that requires SQS:
fake_sqs.start

# at the end of the suite:
at_exit {
  fake_sqs.stop
}

By starting it like this it will start when needed, and reset between each test.

Here's an example for RSpec to put in spec/spec_helper.rb:

AWS.config(
  use_ssl:            false,
  sqs_endpoint:       "localhost",
  sqs_port:           4568,
  access_key_id:      "fake access key",
  secret_access_key:  "fake secret key",
)

RSpec.configure do |config|
  config.treat_symbols_as_metadata_keys_with_true_values = true
  config.before(:suite) { $fake_sqs = FakeSQS::TestIntegration.new }
  config.before(:each, :sqs) { $fake_sqs.start }
  config.after(:suite) { $fake_sqs.stop }
end

Now you can use the `:sqs metadata to enable SQS integration:

describe "something with sqs", :sqs do
  it "should work" do
    queue = AWS::SQS.new.queues.create("my-queue")
  end
end

Development

Run all the specs:

$ rake

This will run the unit tests, then the acceptance tests for both types of storage (in-memory and on disk).

When debugging an acceptance test, you can run it like this, which will redirect output to the console:

$ DEBUG=true SQS_DATABASE=tmp/sqs.yml rspec spec/acceptance