Enable TOSCA to be able to generate other target languages
Currently TOSCA only provides a translation service to the target HOT language. With the emergence of containers, there are now use cases where the direct translation of TOSCA to specific container orchestration engines (Kubernetes, Swarm, Nulecule, etc...) is useful. This blueprint serves to capture the intent to allow the translator component to be flexible enough that plugins can be provided in order to provide translation support for these additional platforms.
Blueprint information
- Status:
- Not started
- Approver:
- Sahdev Zala
- Priority:
- Low
- Drafter:
- Julio Ruano
- Direction:
- Needs approval
- Assignee:
- None
- Definition:
- Discussion
- Series goal:
- None
- Implementation:
-
Not started
- Milestone target:
- None
- Started by
- Completed by
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Specifically, the translator will need to provide plugin entry points to be configured through the new global configuration capability:
https:/
The following configuration option would need to be added, "target_language"
It should also allow for the management of the plugin code via the supported stevedore python library.
From a design perspective, this will require a common base class for the main translate modules:
translate_inputs.py
translate_
translate_
Each will derive from a base class that generalizes the interface for the specific implementations, most likely the translate() method. Organizing the code should also enforce this plugin design. For example:
heat-translator/
contrib/
k8s/ (i.e. kubernetes specific implementation)
swarm/ (i.e. swarm specific implementation)
translator/
hot/ (default hot specific implementation)
Deliverables for this blueprint include the following:
- Reorganization of code to enforce plugin design
- Development of a base class to generalize the translation interface and allow for specialization supporting different target languages through derived classes. Fix existing code to use these new common base classes
- Addition of configuration option to specify correct target_language
- Code to leverage a plugin manager (stevedore) in order to load appropriate language translation classes (specified in configuration). Initial implementation of this blueprint will be to default to current HOT translation code, and to allow the ability to switch to something like kubernetes. Implementation for new target language is out of scope for this blueprint.
