Quickly check links in Markdown, HTML, and text files using lychee.
When used in conjunction with Create Issue From File, issues will be
opened when the action finds link problems (make sure to specify the issues: write permission in the workflow or the job).
Here is a full example of a GitHub workflow file:
It will check all repository links once per day and create an issue in case of
errors. Save this under .github/workflows/links.yml:
name: Links
on:
repository_dispatch:
workflow_dispatch:
schedule:
- cron: "00 18 * * *"
jobs:
linkChecker:
runs-on: ubuntu-latest
permissions:
issues: write # required for peter-evans/create-issue-from-file
steps:
- uses: actions/checkout@v4
- name: Link Checker
id: lychee
uses: lycheeverse/lychee-action@v2
- name: Create Issue From File
if: ${{ steps.lychee.outputs.exit_code }} != 0
uses: peter-evans/create-issue-from-file@v5
with:
title: Link Checker Report
content-filepath: ./lychee/out.md
labels: report, automated issueThis action uses lychee for link checking.
lychee arguments can be passed to the action via the args parameter.
On top of that, the action also supports some additional arguments.
| Argument | Examples | Description |
|---|---|---|
| args | --cache, --insecure |
See lychee's documentation for all arguments and values |
| debug | false |
Enable debug output in action (set -x). Helpful for troubleshooting |
| fail | false |
Fail workflow run on error (i.e. when lychee exit code is not 0) |
| failIfEmpty | false |
Fail entire pipeline if no links were found |
| format | markdown, json |
Summary output format |
| jobSummary | false |
Write GitHub job summary (on Markdown output only) |
| lycheeVersion | v0.15.0, nightly |
Overwrite the lychee version to be used |
| output | lychee/results.md |
Summary output file path |
| token | "" |
Custom GitHub token to use for API calls |
See action.yml for a full list of supported arguments and their default values.
Here is how to pass the arguments.
- name: Link Checker
uses: lycheeverse/lychee-action@v2
with:
# Check all markdown, html and reStructuredText files in repo (default)
args: --base . --verbose --no-progress './**/*.md' './**/*.html' './**/*.rst'
# Use json as output format (instead of markdown)
format: json
# Use different output file path
output: /tmp/foo.txt
# Use a custom GitHub token, which
token: ${{ secrets.CUSTOM_TOKEN }}
# Don't fail action on broken links
fail: false(If you need a token that requires permissions that aren't available in the
default GITHUB_TOKEN, you can create a personal access
token
and pass it to the action via the token parameter.)
In order to mitigate issues regarding rate limiting or to reduce stress on external resources, one can setup lychee's cache similar to this:
- name: Restore lychee cache
uses: actions/cache@v4
with:
path: .lycheecache
key: cache-lychee-${{ github.sha }}
restore-keys: cache-lychee-
- name: Run lychee
uses: lycheeverse/lychee-action@v2
with:
args: "--base . --cache --max-cache-age 1d ."It will compare and save the cache based on the given key. So in this setup, as long as a user triggers the CI run from the same commit, it will be the same key. The first run will save the cache, subsequent runs will not update it (because it's the same commit hash). For restoring the cache, the most recent available one is used (commit hash doesn't matter).
If you need more control over when caches are restored and saved, you can split the cache step and e.g. ensure to always save the cache (also when the link check step fails):
- name: Restore lychee cache
id: restore-cache
uses: actions/cache/restore@v4
with:
path: .lycheecache
key: cache-lychee-${{ github.sha }}
restore-keys: cache-lychee-
- name: Run lychee
uses: lycheeverse/lychee-action@v2
with:
args: "--base . --cache --max-cache-age 1d ."
- name: Save lychee cache
uses: actions/cache/save@v4
if: always()
with:
path: .lycheecache
key: ${{ steps.restore-cache.outputs.cache-primary-key }}Add a .lycheeignore file to the root of your repository to exclude links from
getting checked. It supports regular expressions. One expression per line.
Pro tip: You can add a little badge to your repo to show the status of your
links. Just replace org with your organisation name and repo with the
repository name and put it into your README.md:
[](https://github.com/org/repo/actions/workflows/links.yml)
It will look like this:
See lychee's Troubleshooting Guide for solutions to common link-checking problems.
A full CI run to scan 576 links takes approximately 1 minute for the analysis-tools-dev/static-analysis repository.
It is recommended to pin lychee-action to a fixed version for security reasons. You can use dependabot to automatically keep your GitHub actions up-to-date. This is a great way to pin lychee-action, while still receiving updates in the future. It's a relatively easy thing to do.
Create a file named .github/dependabot.yml with the following contents:
version: 2
updates:
- package-ecosystem: "github-actions"
directory: ".github/workflows"
schedule:
interval: "daily"When you add or update the dependabot.yml file, this triggers an immediate check for version updates.
Please see the documentation for all configuration options.
For additional security when relying on automation to update actions you can pin the action to a SHA-256 rather than the semver version so as to avoid tag spoofing Dependabot will still be able to automatically update this.
For example:
- name: Link Checker
uses: lycheeverse/lychee-action@7da8ec1fc4e01b5a12062ac6c589c10a4ce70d67 # for v2.0.0This action is based on the deprecated peter-evans/link-checker and uses lychee (written in Rust) instead of liche (written in Go) for link checking.
lychee is licensed under either of
at your option.