# golangci-lint-action

[![Build Status](https://github.com/golangci/golangci-lint-action/workflows/build-and-test/badge.svg)](https://github.com/golangci/golangci-lint-action/actions)

It's the official GitHub Action for [golangci-lint](https://github.com/golangci/golangci-lint) from its authors.

The action runs [golangci-lint](https://github.com/golangci/golangci-lint) and reports issues from linters.

![GitHub Annotations](./static/annotations.png)

![Logs](./static/colored-line-number.png)

## Supporting Us

[![GitHub Sponsors](https://img.shields.io/badge/GitHub-Donate-blue?logo=github&style=for-the-badge)](https://github.com/sponsors/golangci)
[![Open Collective backers and sponsors](https://img.shields.io/badge/OpenCollective-Donate-blue?logo=opencollective&style=for-the-badge)](https://opencollective.com/golangci-lint)
[![Linter Authors](https://img.shields.io/badge/Linter_Authors-Donate-blue?style=for-the-badge)](https://golangci-lint.run/product/thanks/)

`golangci-lint` is a free and open-source project built by volunteers.

If you value it, consider supporting us; we appreciate it! :heart:

## How to use

We recommend running this action in a job separate from other jobs (`go test`, etc.)
because different jobs [run in parallel](https://help.github.com/en/actions/getting-started-with-github-actions/core-concepts-for-github-actions#job).

Add a `.github/workflows/golangci-lint.yml` file with the following contents:

<details>
<summary>Simple Example</summary>

```yaml
name: golangci-lint
on:
  push:
    branches:
      - main
      - master
  pull_request:

permissions:
  contents: read
  # Optional: allow read access to pull requests. Use with `only-new-issues` option.
  # pull-requests: read

jobs:
  golangci:
    name: lint
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5
      - uses: actions/setup-go@v6
        with:
          go-version: stable
      - name: golangci-lint
        uses: golangci/golangci-lint-action@v9
        with:
          version: v2.6
```

</details>

<details>
<summary>Multiple OS Example</summary>

```yaml
name: golangci-lint
on:
  push:
    branches:
      - main
      - master
  pull_request:

permissions:
  contents: read
  # Optional: allow read access to pull requests. Use with `only-new-issues` option.
  # pull-requests: read

jobs:
  golangci:
    strategy:
      matrix:
        go: [stable]
        os: [ubuntu-latest, macos-latest, windows-latest]
    name: lint
    runs-on: ${{ matrix.os }}
    steps:
      - uses: actions/checkout@v5
      - uses: actions/setup-go@v6
        with:
          go-version: ${{ matrix.go }}
      - name: golangci-lint
        uses: golangci/golangci-lint-action@v9
        with:
          version: v2.6
```

You will also likely need to add the following `.gitattributes` file to ensure that line endings for Windows builds are properly formatted:

```.gitattributes
*.go text eol=lf
```

</details>

<details>
<summary>Go Workspace Example</summary>

```yaml
name: golangci-lint

on:
  pull_request:
  push:
    branches:
      - main
      - master

env:
  GO_VERSION: stable
  GOLANGCI_LINT_VERSION: v2.6

jobs:
  detect-modules:
    runs-on: ubuntu-latest
    outputs:
      modules: ${{ steps.set-modules.outputs.modules }}
    steps:
      - uses: actions/checkout@v5
      - uses: actions/setup-go@v6
        with:
          go-version: ${{ env.GO_VERSION }}
      - id: set-modules
        run: echo "modules=$(go list -m -json | jq -s '.' | jq -c '[.[].Dir]')" >> $GITHUB_OUTPUT

  golangci-lint:
    needs: detect-modules
    runs-on: ubuntu-latest
    strategy:
      matrix:
        modules: ${{ fromJSON(needs.detect-modules.outputs.modules) }}
    steps:
      - uses: actions/checkout@v5
      - uses: actions/setup-go@v6
        with:
          go-version: ${{ env.GO_VERSION }}
      - name: golangci-lint ${{ matrix.modules }}
        uses: golangci/golangci-lint-action@v9
        with:
          version: ${{ env.GOLANGCI_LINT_VERSION }}
          working-directory: ${{ matrix.modules }}
```

</details>

<details>
<summary>Go Workspace Example (Multiple OS)</summary>

```yaml
# ./.github/workflows/golangci-lint.yml
name: golangci-lint (multi OS)

on:
  pull_request:
  push:
    branches:
      - main
      - master

jobs:
  golangci-lint:
    strategy:
      matrix:
        go-version: [ stable, oldstable ]
        os: [ubuntu-latest, macos-latest, windows-latest]
    uses: ./.github/workflows/.golangci-lint-reusable.yml
    with:
      os: ${{ matrix.os }}
      go-version: ${{ matrix.go-version }}
      golangci-lint-version: v2.6
```

```yaml
# ./.github/workflows/.golangci-lint-reusable.yml
name: golangci-lint-reusable

on:
  workflow_call:
    inputs:
      os:
        description: 'OS'
        required: true
        type: string
      go-version:
        description: 'Go version'
        required: true
        type: string
        default: stable
      golangci-lint-version:
        description: 'Golangci-lint version'
        type: string
        default: 'v2.6'

jobs:
  detect-modules:
    runs-on: ${{ inputs.os }}
    outputs:
      modules: ${{ steps.set-modules.outputs.modules }}
    steps:
      - uses: actions/checkout@v5
      - uses: actions/setup-go@v6
        with:
          go-version: ${{ inputs.go-version }}
      - id: set-modules
        shell: bash # required for Windows to be able to use $GITHUB_OUTPUT https://github.com/actions/runner/issues/2224
        run: echo "modules=$(go list -m -json | jq -s '.' | jq -c '[.[].Dir]')" >> $GITHUB_OUTPUT

  golangci-lint:
    needs: detect-modules
    runs-on: ${{ inputs.os }}
    strategy:
      matrix:
        modules: ${{ fromJSON(needs.detect-modules.outputs.modules) }}
    steps:
      - uses: actions/checkout@v5
      - uses: actions/setup-go@v6
        with:
          go-version: ${{ inputs.go-version }}
      - name: golangci-lint ${{ matrix.modules }}
        uses: golangci/golangci-lint-action@v9
        with:
          version: ${{ inputs.golangci-lint-version }}
          working-directory: ${{ matrix.modules }}
```

You will also likely need to add the following `.gitattributes` file to ensure that line endings for Windows builds are properly formatted:

```.gitattributes
*.go text eol=lf
```

</details>

## Compatibility

* `v9.0.0` requires Nodejs runtime [`node24`](https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/)
* `v8.0.0` works with `golangci-lint` version >= `v2.1.0`
* `v8.0.0` works with `golangci-lint` version >= `v2.1.0`
* `v7.0.0` supports golangci-lint v2 only.
* `v6.0.0+` removes `annotations` option, removes the default output format (`github-actions`).
* `v5.0.0+` removes `skip-pkg-cache` and `skip-build-cache` because the cache related to Go itself is already handled by `actions/setup-go`.
* `v4.0.0+` requires an explicit `actions/setup-go` installation step before using this action: `uses: actions/setup-go@v5`.
  The `skip-go-installation` option has been removed.
* `v2.0.0+` works with `golangci-lint` version >= `v1.28.3`
* `v1.2.2` is deprecated because we forgot to change the minimum version of `golangci-lint` to `v1.28.3` ([issue](https://github.com/golangci/golangci-lint-action/issues/39))
* `v1.2.1` works with `golangci-lint` version >= `v1.14.0` ([issue](https://github.com/golangci/golangci-lint-action/issues/39))

## Options

### Overview

| Option                                                        | Description                                        |
|---------------------------------------------------------------|----------------------------------------------------|
| [`version`](#version)                                         | The version of golangci-lint to use.               |
| [`install-mode`](#install-mode)                               | The mode to install golangci-lint.                 |
| [`install-only`](#install-only)                               | Only install golangci-lint.                        |
| [`verify`](#verify)                                           | Validates golangci-lint configuration file.        |
| [`github-token`](#github-token)                               | Used by the `only-new-issues` option.              |
| [`only-new-issues`](#only-new-issues)                         | Show only new issues.                              |
| [`working-directory`](#working-directory)                     | The golangci-lint working directory.               |
| [`args`](#args)                                               | Golangci-lint command line arguments.              |
| [`skip-cache`](#skip-cache)                                   | Disable cache support.                             |
| [`skip-save-cache`](#skip-save-cache)                         | Don't save cache.                                  |
| [`cache-invalidation-interval`](#cache-invalidation-interval) | Number of days before cache invalidation.          |
| [`problem-matchers`](#problem-matchers)                       | Forces the usage of the embedded problem matchers. |

### Installation

#### `version`

(optional)

The version of golangci-lint to use.

When `install-mode` is:
* `binary` (default): the value can be v2.3, v2.3.4, or `latest` to use the latest version.
* `goinstall`: the value can be v2.3.4, `latest`, or the hash of a commit.
* `none`: the value is ignored.

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  version: v2.6
  # ...
```

</details>

#### `install-mode`

(optional)

The mode to install golangci-lint: it can be `binary`, `goinstall`, or `none`.

The default value is `binary`.

`goinstall` is not recommended, more explanations [here](https://golangci-lint.run/docs/welcome/install/#install-from-sources).

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  install-mode: "none"
  # ...
```

</details>

#### `install-only`

(optional)

If set to `true`, the action will only install golangci-lint.
It does not run golangci-lint.

The default value is `false`.

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  install-only: true
  # ...
```

</details>

### Run

#### `verify`

(optional)

This option is `true` by default.

If the GitHub Action detects a configuration file, validation will be performed unless this option is set to `false`.
If there is no configuration file, validation is skipped.

The JSON Schema used to validate the configuration depends on the version of golangci-lint you are using.

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  verify: false
  # ...
```

</details>

#### `github-token`

(optional)

When using the `only-new-issues` option, the GitHub API is used, so a token is required.

By default, it uses the `github.token` from the action.

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  github-token: xxx
  # ...
```

</details>

#### `only-new-issues`

(optional)

Show only new issues.

The default value is `false`.

* `pull_request` and `pull_request_target`: the action gets the diff of the PR content from the [GitHub API](https://docs.github.com/en/rest/pulls/pulls?apiVersion=2022-11-28#get-a-pull-request) and uses it with `--new-from-patch`.
* `push`: the action gets the diff of the push content (the difference between commits before and after the push) from the [GitHub API](https://docs.github.com/en/rest/commits/commits?apiVersion=2022-11-28#compare-two-commits) and uses it with `--new-from-patch`.
* `merge_group`: the action gets the diff by using the `--new-from-rev` option (relies on git).
  You should add the option `fetch-depth: 0` to the `actions/checkout` step.

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  only-new-issues: true
  # ...
```

</details>

#### `working-directory`

(optional)

The golangci-lint working directory, useful for monorepos. The default is the project root.

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  working-directory: somedir
  # ...
```

</details>

#### `args`

(optional)

golangci-lint command line arguments.

> [!NOTE]
> By default, the `.golangci.yml` file should be at the root of the repository.
> The location of the configuration file can be changed by using `--config=`.

> [!IMPORTANT]
> Adding a `=` between the flag name and its value is important because the action parses the arguments on spaces.

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  # In some rare cases,
  # you may need to use `${{ github.workspace }}` as the base directory to reference your configuration file.
  args: --config=/my/path/.golangci.yml --issues-exit-code=0
  # ...
```

</details>

### Cache

#### `skip-cache`

(optional)

If set to `true`, all caching functionality will be completely disabled.
This takes precedence over all other caching options.

The default value is `false`.

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  skip-cache: true
  # ...
```

</details>

#### `skip-save-cache`

(optional)

If set to `true`, caches will not be saved, but they may still be restored, requiring `skip-cache: false`.

The default value is `false`.

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  skip-save-cache: true
  # ...
```

</details>

#### `cache-invalidation-interval`

(optional)

Periodically invalidate a cache every `cache-invalidation-interval` days to ensure that outdated data is removed and fresh data is loaded.

The default value is `7`.

If the number is `<= 0`, the cache will always be invalidated (not recommended).

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  cache-invalidation-interval: 15
  # ...
```

</details>

### Extra

#### `problem-matchers`

(optional)

Forces the usage of the embedded problem matchers.

By default, the [problem matcher of Go (`actions/setup-go`)](https://github.com/actions/setup-go/blob/main/matchers.json) already handles the default golangci-lint output (`text`).

Works only with the `text` format (the golangci-lint default).

https://golangci-lint.run/usage/configuration/#output-configuration

The default value is `false`.

<details>
<summary>Example</summary>

```yml
uses: golangci/golangci-lint-action@v9
with:
  problem-matchers: true
  # ...
```

</details>

## Annotations

Currently, GitHub parses the action's output and creates [annotations](https://github.blog/2018-12-14-introducing-check-runs-and-annotations/).

The restrictions of annotations are as follows:

1. Currently, they don't support Markdown formatting (see the [feature request](https://github.community/t5/GitHub-API-Development-and/Checks-Ability-to-include-Markdown-in-line-annotations/m-p/56704)).
2. They aren't shown in the list of comments.
   If you would like to have comments, please up-vote [the issue](https://github.com/golangci/golangci-lint-action/issues/5).
3. The number of annotations is [limited](https://github.com/actions/toolkit/blob/main/docs/problem-matchers.md#limitations).

Permissions required:

```yaml annotate
permissions:
  # Required: allow read access to the content for analysis.
  contents: read
  # Optional: allow read access to pull requests. Use with `only-new-issues` option.
  pull-requests: read
```

For annotations to work, use the default format output (`text`) and either use [`actions/setup-go`](https://github.com/actions/setup-go) in the job or enable the internal [problem matchers](#problem-matchers).

## Module Plugin System

The action will automatically detect the custom build configuration file `.custom-gcl.yml`,
build and run the custom version of golangci-lint.

For more information, see [module plugin system](https://golangci-lint.run/docs/plugins/module-plugins/).

## Performance

The action was implemented with performance in mind:

1. We cache data from golangci-lint analysis between builds by using [@actions/cache](https://github.com/actions/toolkit/tree/HEAD/packages/cache).
2. We don't use Docker because image pulling is slow.
3. We do as much as we can in parallel, e.g., we download the cache and the golangci-lint binary in parallel.
4. We rely on [`actions/setup-go`](https://github.com/actions/setup-go) for Go module cache.

## Internals

We use a JavaScript-based action.
We don't use a Docker-based action because:

1. Pulling Docker images is currently slow.
2. It is easier to use caching from [@actions/cache](https://github.com/actions/toolkit/tree/HEAD/packages/cache).

We support different platforms, such as `ubuntu`, `macos`, and `windows` with `x32` and `x64` architectures.

Inside our action, we perform three steps:

1. Set up the environment in parallel:
   * Restore the [cache](https://github.com/actions/cache) from previous analyses.
   * Fetch the [action config](https://github.com/golangci/golangci-lint/blob/HEAD/assets/github-action-config.json) and find the latest `golangci-lint` patch version for the required version
     (users of this action can specify only the minor version of `golangci-lint`).
     After that, install [golangci-lint](https://github.com/golangci/golangci-lint) using [@actions/tool-cache](https://github.com/actions/toolkit/tree/HEAD/packages/tool-cache).
2. Run `golangci-lint` with the arguments `args` specified by the user.
3. Save the cache for later builds.

### Caching internals

1. We save and restore the following directory: `~/.cache/golangci-lint`.
2. The primary caching key looks like `golangci-lint.cache-{runner_os}-{working_directory}-{interval_number}-{go.mod_hash}`.
   The interval number ensures that we periodically invalidate our cache (every 7 days).
   The `go.mod` hash ensures that we invalidate the cache early — as soon as dependencies have changed.
3. We use [restore keys](https://help.github.com/en/actions/configuring-and-managing-workflows/caching-dependencies-to-speed-up-workflows#matching-a-cache-key):
   `golangci-lint.cache-{runner_os}-{working_directory}-{interval_number}-`.
   GitHub matches keys by prefix if there is no exact match for the primary cache.

This scheme is basic and needs improvements. Pull requests and ideas are welcome.