Dependent Cloudify Plugin

This plugin demonstrates an approach to using the code (and, indirectly, types) of another Cloudify plugin within another plugin.

The challenge is that Cloudify deploys each plugin individually, so when the plugin runs remotely, it does not bring along any dependencies.

Solution: embed + requirements + blueprint embedded

Constraint: this plugin must be embedded into the blueprint; it cannot (yet) be used online or managed.

It forms 3 parts: the embedded plugin, the requirements file and the plugin declaration

The embedded plugin

The plugin this depends on (example-cloudify-plugin) is git subtree'd into the dependencies directory, so that the code is entirely present.

The requirements file & the plugin declaration

Cloudify allows plugins to specify extra install_arguments that are supplied to pip during plugin install time.

The requirements file looks like this:

    dependencies/example-cloudify-plugin/

The plugin declaration looks like so:

    plugins:
      dependent:
        executor: central_deployment_agent
        source: dependent-cloudify-plugin
        install_arguments: -r embedded-requirements.txt

Dependent types

This plugin's type antillion.demo.DependentNode derives from the other plugins type antillion.demo.DummyNode`, however this plugin makes no reference to the other plugin's type file.

To use this plugin, the blueprint must explicitly include the other plugin's type file. When Cloudify brings the entire blueprint together, the hierarchy will be valid.

Usage

With both plugins embedded into a blueprint, a working example looks like this:

    tosca_definitions_version: cloudify_dsl_1_3

    imports:
      - http://www.getcloudify.org/spec/cloudify/3.4.1/types.yaml
      - plugins/example-cloudify-plugin/embedded.plugin.yml
      - plugins/example-cloudify-plugin/types/dummy.types.yml
      - plugins/example-dependent-cloudify-plugin/depends-embedded.plugin.yml
      - plugins/example-dependent-cloudify-plugin/types/depends.types.yml

    node_templates:
      dummy1:
        type: antillion.demo.DummyNode


      dependent1:
        type: antillion.demo.DependentNode

Final notes

It's important to note that this plugin's setup.py does not declare the dependent plugin in install_requires.