Analyzers and linters

The following are the different checks that Charmcraft will run explicitly (when the user executes its analyze method) or implicitly (when packing charms).

You can read more about these checks in the Charmcraft Analyze Specification.

Attribute Checks

These are checks for characteristics or attributes identified from the charm.

Language Attribute

If through analysis, the charm can be detected as being a Python based charm, then language shall be set to python. If not, it shall be set to unknown.

When working with Python, it is possible to only publish byte-code. By doing so, troubleshooting is a harder task. Charms with Python sources delivered are preferred.

This attribute meets the requirements to be set to python when:

  • the charm has a text dispatch which executes a .py
  • the charm has a .py entry point
  • the entry point file is executable

Framework Attribute

When using the Operator Framework, it is best to import it from a common path and not make customisation or package forks from it. If the Operator Framework is detected in the charm sources, this attribute’s value shall be set to operator. If not, the charm may be using the Reactive Framework, and in this case the attribute value will be reactive. Else, it shall be set to unknown.

This check hint meets the requirements for Operative Framework when:

  • language attribute is set to python
  • the charm contains venv/ops
  • the charm imports ops in the entry point

The requirements for Reactive Framework are:

…or the Reactive Framework is used, if the charm…

  • has a metadata.yaml with name in it
  • has a reactive/<name>.py file that imports charms.reactive
  • has a file name that starts with charms.reactive- inside the wheelhouse directory

Juju Metadata Linter

This linter verifies that the metadata.yaml file exists and is sane.

The charm is considered to have a valid metadata if the following checks are true:

  • the metadata.yaml is present
  • it is a valid YAML file
  • it has at least the following fields: name, summary, and description

Last updated 20 days ago.

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