Helpers

The task_definitions.rb file has access to helper methods. These helper methods provide useful contextual information about the project.

For example, one of the helper methods provides the exposed port in the Dockerfile of the project. This is useful if someone changes the exported port in the Dockerfile, he will likely forget also to update the ufo variable. You can reference the port via the helper to prevent this from happening. Here is a list of the helpers:

Helper	Description
full_image_name	The full docker image name that ufo builds. The “base” portion of the docker image name is defined in settings.yml. For example, the base portion is tongueroo/demo-ufo and the full image name is tongueroo/demo-ufo:ufo-[timestamp]-[sha]. The base name does not include the generated Docker tag, which contains a timestamp and git sha of the project.
dockerfile_port	Exposed port extracted from the Dockerfile of the project.
env_vars(text)	This method takes a block of text that contains the env values in key=value format and converts that block of text to the proper task definition JSON format.
env_file(path)	This method takes a .env file which contains a simple key-value list of environment variables and converts the list to the proper task definition JSON format.
secrets_vars(text)	This method takes a block of text that contains the secrets values in key=value format and converts that block of text to the proper task definition JSON format.
secrets_file(path)	This method takes a .secrets file which contains a simple key-value list of environment variables and converts the list to the proper task definition JSON format.
task_definition_name	The name of the task_definition. So if the code looks like this task_definition "demo-web" do, the task_definition_name is “demo-web”.

To call the helper in task_definitions.rb you must add helper. in front. So full_image_name is called via helper.full_image_name.

The 2 classes which provide these special helper methods are in ufo/dsl.rb and ufo/dsl/helper.rb. Refer to these classes for the full list of the helper methods.

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