# eleventy-plugin-git-commit-date

This Eleventy plugin provides two [template filters](https://www.11ty.dev/docs/filters/):

| Filter                             | Description                                                                                                                                   |
| :--------------------------------- | :-------------------------------------------------------------------------------------------------------------------------------------------- |
| `getGitCommitDateFromPath`         | Gets Git commit date from path.<br><br>Usage: `{{ page.inputPath \| getGitCommitDateFromPath }}`                                              |
| `getCollectionNewestGitCommitDate` | Get Git commit date of the newest committed file from a collection.<br><br>Usage: `{{ collections.all \| getCollectionNewestGitCommitDate }}` |

🌏 This plugin is made primarily to populate `<updated>` fields in an RSS feed. Here is [a blog post on how to use this plugin](https://saneef.com/tutorials/fix-dates-on-eleventy-rss-feeds/) with [`eleventy-plugin-rss`](https://www.11ty.dev/docs/plugins/rss/).

## Usage

### 1. Install

```sh
npm install eleventy-plugin-git-commit-date
```

### 2. Add to Eleventy config

```js
// eleventy.config.js

import pluginGitCommitDate from "eleventy-plugin-git-commit-date";

export default function (eleventyConfig) {
  eleventyConfig.addPlugin(pluginGitCommitDate);
}
```

### 3. Use in templates

```nunjucks
Using {{ page.inputPath | getGitCommitDateFromPath }} will display the git commit date of the file using a local time zone like:

Sun Dec 31 2017 18:00:00 GMT-0600 (Central Standard Time)

Using {{ collections.all | getCollectionNewestGitCommitDate }} will display the git commit date of newest file in the collection using a local time zone like:

Sun Dec 31 2017 18:00:00 GMT-0600 (Central Standard Time)
```

## FAQs

### When used with GitHub Pages, why are the last commit dates incorrect?

Only the last commit is checked out by [GitHub Action Checkout](https://github.com/actions/checkout#:~:text=Only%20a%20single%20commit%20is%20fetched%20by%20default) by default. The commit dates for files changed in the previous commits will not be available. You can set the `fetch-depth` as `0` to get all the history from the Git repository.

```diff
   - name: Checkout
     uses: actions/checkout@v3
+    with:
+      fetch-depth: 0
```

## Credits

- [@zachleat](https://github.com/11ty/eleventy/issues/142) suggested the use of Git commit dates instead of modified date.
- The core code is based on Jens Oliver Meiert' blog post [Eleventy: How to Work Around the “git Last Modified” Performance Bottleneck](https://meiert.com/blog/eleventy-git-last-modified/).
- Pre v1.0 was based on [@vuepress/plugin-last-updated](https://github.com/vuejs/vuepress/tree/master/packages/@vuepress/plugin-last-updated).