Allow specifying a separate application name so that sub applications…

[eyespies]

… can be deployed without having to change server tags. We have a use case where we build and deploy multiple, separate, applications as different directories within a single virtual host where we also have multiple hosts, e.g. the Widget application is deployed to the Factory host as http://www.factory.com/widget/ and the Water and Fish applications are deployed to the Ocean host as http://www.ocean.com/water/ and http://www.ocean.com/fish/.

In order to prevent the need for us to create a very long tag value (Tag Name=Projects, Tag Value=widget1,widget2,widget3,widget4, etc) we want to group the applications based on the host/domain name and not the application name. To accomplish this, we have created an override value called ec2_application which supersedes the application setting but only if it is set.

This does not affect existing behavior because it defaults to using the normal :application setting if the :ec2_application value is not set. My Ruby skills are only moderate, so please double check the if ... statement I wrote.

I tested this by doing the following:

1. Test that :application value still works
   • Configure Capistrano with only the :application value
   • Configure a single server with the Project tag set to the :application value
   • Run cap dev ec2:status --> the one server was returned (expected behavior)
2. Test a missing :ec2_application shows no results
   • Configure Capistrano with only the :application value
   • Configure a single server with the Project tag set to a value OTHER than the :application value
   • Run cap dev ec2:status --> no results returned (the expected behavior)
3. Test that :ec2_application value overrides the :application value
   • Configure Capistrano with both the :application value AND the :ec2_application value
   • Configure a single server with the Project tag set to the :application value
   • Run cap dev ec2:status --> no results returned (the expected behavior)
   • Configure Capistrano with both the :application value AND the :ec2_application value
   • Configure a single server with the Project tag set to the :ec2_application value
   • Run cap dev ec2:status --> one result returned (the expected behavior)