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opa-fmt

Summary: File should be formatted with opa fmt

Category: Style

Automatically fixable: Yes

Avoid

Inconsistent style across policy files and repositories.

Rationale​

The opa fmt tool ensures consistent formatting across teams and projects. Unified formatting is a big win, and saves a lot of time in code reviews arguing over details around style.

A good idea could be to run opa fmt --write on save, which can be configured in most editors.

Tip: opa fmt uses tabs for indentation. By default, GitHub uses 8 spaces to display tabs, which is arguably a bit much. You can change this preference for your account in github.com/settings/appearance, or provide an .editorconfig file in your policy repository, which will be used by GitHub (and other tools) to properly display your Rego files:

[*.rego]
end_of_line = lf
insert_final_newline = true
charset = utf-8
indent_style = tab
indent_size = 4

OPA Format with Rego v1 and v0​

OPA 1.0 makes Rego v1 the default. This change mandated some changes to the functionality of the opa fmt command and a number of new options for working with mixed version code bases. See the OPA documentation for the command's options.

In Regal, a v0 file will have the opa-fmt violation unless it's been formatted with opa fmt --v0-v1. A v1 file will have the opa-fmt violation unless it's been formatted with opa fmt (the rego.v1 keyword is permitted but not added).

When formatting, a file expected to be v1 based on the configuration, but with v0 syntax is still formatted as opa fmt –-v0-v1. Please see Configuring Rego Version for more configuration help for multi version projects.

Configuration Options​

This linter rule provides the following configuration options:

rules:
  style:
    opa-fmt:
      # one of "error", "warning", "ignore"
      level: error

Community​

If you think you've found a problem with this rule or its documentation, would like to suggest improvements, new rules, or just talk about Regal in general, please join us in the #regal channel in the Styra Community Slack!