Linting Patterns

How to lint Patterns for syntax errors, security issues, and formatting mistakes in Etcha.

Etcha can lint Patterns, libraries, and more–basically if it’s written in Jsonnet, Etcha can probably lint it.

Performing Linting

You can lint an entire path or specific files using etcha lint. Lint will traverse directories and perform linting on all .jsonnet and .libsonnet files. It will ensure they can be imported into Etcha correctly. Any errors will be shown in the console, and the tool will exit with a non-zero status code.

You can also check the formatting of the files by adding the flag -f : etcha -c lint mydir. Formatting errors will be reported, along with diffs on what the correct formatting should be. The tool will exit with a non-zero status code on formatting errors, too.

For Continuous Delivery/Continuous Integration Usage, it’s highly recommended to run linting across your entire Etcha codebase.

Test Mode

Linting and Testing both set a flag within the config called test to true. You can retrieve this value within Jsonnet and adjust your Pattern files to render differently during test mode, i.e.:

// lib/mylib.libsonnet
local n = import '../etcha/native.libsonnet';
local config = n.getConfig();

  check: (if config.test then '' else '[[ -d "/mydir" ]]'),
  id: 'hello world',

In this example, check will be an empty string in test mode.

External Linters

In addition to linting the Jsonnet syntax, Etcha can combine the change, check, and remove scripts and pass them through external linters via stdin. These external linters are configured under lint.

Out of the box, Etcha is configured to use Shellcheck as an external linter. Any external linter failures will be reported in the console, and Etcha will exit with a non-zero code.