feat: convert relative urls to absolute (#125)

README.md

@@ -25,6 +25,8 @@ This is useful if you `docker push` your images to Docker Hub. It provides an ea
 | `repository` | Docker Hub repository in the format `<namespace>/<name>`. | `github.repository` |
 | `short-description` | Docker Hub repository short description. | |
 | `readme-filepath` | Path to the repository readme. | `./README.md` |
+| `enable-url-completion` | Enables completion of relative URLs to absolute ones. See also [Known Issues](#known-issues). | `false` |
+| `image-extensions` | File extensions that will be treated as images. | `bmp,gif,jpg,jpeg,png,svg,webp` |
 
 #### Content limits
 
@@ -86,6 +88,7 @@ jobs:
         password: ${{ secrets.DOCKERHUB_PASSWORD }}
         repository: peterevans/dockerhub-description
         short-description: ${{ github.event.repository.description }}
+        enable-url-completion: true
 ```
 
 Updates the Docker Hub repository description whenever a new release is created.
@@ -122,6 +125,38 @@ docker run -v $PWD:/workspace \
   peterevans/dockerhub-description:3
 ```
 
+## Known Issues
+
+The completion of relative urls has some known issues:
+
+1. Relative markdown links in inline-code and code blocks **are also converted**:
+
+   ```markdown
+   [link in inline code](#table-of-content)
+   ```
+
+   will be converted into
+
+   ```markdown
+   [link in inline code](https://github.com/peter-evans/dockerhub-description/blob/main/./README.md#table-of-content)
+   ```
+
+2. Links containing square brackets (`]`) in the text fragment **are not converted**:
+
+   ```markdown
+   [[link text with square brackets]](#table-of-content)
+   ```
+
+3. [Reference-style links/images](https://www.markdownguide.org/basic-syntax/#reference-style-links) **are not converted**.
+
+   ```markdown
+   [table-of-content][toc]
+
+   ...
+
+   [toc]: #table-of-content "Table of content"
+   ```
+
 ## License
 
 [MIT](LICENSE)

__test__/readme-helper.unit.test.ts

@@ -0,0 +1,335 @@
+import {completeRelativeUrls} from '../src/readme-helper'
+
+describe('complete relative urls tests', () => {
+  const GITHUB_SERVER_URL = process.env['GITHUB_SERVER_URL']
+  const GITHUB_REPOSITORY = process.env['GITHUB_REPOSITORY']
+  const GITHUB_REF_NAME = process.env['GITHUB_REF_NAME']
+
+  const README_FILEPATH = './README.md'
+  const EXPECTED_REPOSITORY_URL = `${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}`
+  const EXPECTED_BLOB_URL = `${EXPECTED_REPOSITORY_URL}/blob/${GITHUB_REF_NAME}`
+  const EXPECTED_RAW_URL = `${EXPECTED_REPOSITORY_URL}/raw/${GITHUB_REF_NAME}`
+
+  // known issues
+  test('reference-style links/image sources are not converted', async () => {
+    const content = [
+      'table-of-content][toc]',
+      '',
+      '[toc]: #table-of-content "Table of content"'
+    ].join('\n')
+    expect(completeRelativeUrls(content, README_FILEPATH, true, '')).toEqual(
+      content
+    )
+  })
+
+  test('links containing square brackets in the text fragment are not converted', async () => {
+    expect(
+      completeRelativeUrls(
+        '[[text with square brackets]](README.md)',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual('[[text with square brackets]](README.md)')
+  })
+
+  test('links containing square brackets in the text fragment are not converted', async () => {
+    expect(
+      completeRelativeUrls('`[text](README.md)`', README_FILEPATH, true, '')
+    ).toEqual(`\`[text](${EXPECTED_BLOB_URL}/README.md)\``)
+  })
+
+  // misc
+  test('do not change content when disabled', async () => {
+    expect(
+      completeRelativeUrls('[text](README.md)', README_FILEPATH, false, '')
+    ).toEqual('[text](README.md)')
+  })
+
+  test('do not change link with mailto protocol', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text](mailto:mail@example.com)',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(`[text](mailto:mail@example.com)`)
+  })
+
+  test('do not change link with ftp protocol', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text](ftp://example.com)',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(`[text](ftp://example.com)`)
+  })
+
+  test('do not change link with http protocol', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text](http://example.com)',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(`[text](http://example.com)`)
+  })
+
+  test('do not change link with https protocol', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text](https://example.com)',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(`[text](https://example.com)`)
+  })
+
+  test('do not change link with protocol-like beginning', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text](abc://example.com)',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(`[text](abc://example.com)`)
+  })
+
+  test('do not change image from absolute source with absolute link', async () => {
+    expect(
+      completeRelativeUrls(
+        '[![alttext](https://example.com/image.svg)](https://example.com/image.svg)',
+        README_FILEPATH,
+        true,
+        'svg'
+      )
+    ).toEqual(
+      `[![alttext](https://example.com/image.svg)](https://example.com/image.svg)`
+    )
+  })
+
+  // anchors
+  test('anchor referencing the current document', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text](#relative-anchor)',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(`[text](${EXPECTED_BLOB_URL}/README.md#relative-anchor)`)
+  })
+
+  test('anchor referencing the current document with a title', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text](#relative-anchor "the anchor (a title)")',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(
+      `[text](${EXPECTED_BLOB_URL}/README.md#relative-anchor "the anchor (a title)")`
+    )
+  })
+
+  test('anchor referencing the current document with a title and unicode', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text with 🌬](#relative-anchor "the anchor (a title with 🌬)")',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(
+      `[text with 🌬](${EXPECTED_BLOB_URL}/README.md#relative-anchor "the anchor (a title with 🌬)")`
+    )
+  })
+
+  test('anchor referencing another document', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text](OTHER.md#absolute-anchor)',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(`[text](${EXPECTED_BLOB_URL}/OTHER.md#absolute-anchor)`)
+  })
+
+  test('anchor referencing another document with a title', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text](OTHER.md#absolute-anchor "the anchor (a title)")',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(
+      `[text](${EXPECTED_BLOB_URL}/OTHER.md#absolute-anchor "the anchor (a title)")`
+    )
+  })
+
+  test('anchor with image referencing the current document', async () => {
+    expect(
+      completeRelativeUrls(
+        '[![alttext](image.svg)](#absolute-anchor "the anchor (a title)")',
+        README_FILEPATH,
+        true,
+        'svg'
+      )
+    ).toEqual(
+      `[![alttext](${EXPECTED_RAW_URL}/image.svg)](${EXPECTED_BLOB_URL}/README.md#absolute-anchor "the anchor (a title)")`
+    )
+  })
+
+  test('anchor with image referencing another document', async () => {
+    expect(
+      completeRelativeUrls(
+        '[![alttext](image.svg)](OTHER.md#absolute-anchor "the anchor (a title)")',
+        README_FILEPATH,
+        true,
+        'svg'
+      )
+    ).toEqual(
+      `[![alttext](${EXPECTED_RAW_URL}/image.svg)](${EXPECTED_BLOB_URL}/OTHER.md#absolute-anchor "the anchor (a title)")`
+    )
+  })
+
+  // documents
+  test('text document', async () => {
+    expect(
+      completeRelativeUrls('[text](document.yaml)', README_FILEPATH, true, '')
+    ).toEqual(`[text](${EXPECTED_BLOB_URL}/document.yaml)`)
+  })
+
+  test('pdf document', async () => {
+    expect(
+      completeRelativeUrls('[text](document.pdf)', README_FILEPATH, true, '')
+    ).toEqual(`[text](${EXPECTED_BLOB_URL}/document.pdf)`)
+  })
+
+  test('document with a title', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text](document.pdf "the document (a title)")',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(
+      `[text](${EXPECTED_BLOB_URL}/document.pdf "the document (a title)")`
+    )
+  })
+
+  test('document with a title and unicode', async () => {
+    expect(
+      completeRelativeUrls(
+        '[text with 🌬](document.pdf "the document (a title with 🌬)")',
+        README_FILEPATH,
+        true,
+        ''
+      )
+    ).toEqual(
+      `[text with 🌬](${EXPECTED_BLOB_URL}/document.pdf "the document (a title with 🌬)")`
+    )
+  })
+
+  // images
+  test('image with supported file extension', async () => {
+    expect(
+      completeRelativeUrls(
+        '![alttext](image.svg)',
+        README_FILEPATH,
+        true,
+        'svg'
+      )
+    ).toEqual(`![alttext](${EXPECTED_RAW_URL}/image.svg)`)
+  })
+
+  test('image with unsupported file extension', async () => {
+    expect(
+      completeRelativeUrls(
+        '![alttext](image.svg)',
+        README_FILEPATH,
+        true,
+        'jpeg'
+      )
+    ).toEqual(`![alttext](${EXPECTED_BLOB_URL}/image.svg)`)
+  })
+
+  test('image without alternate text', async () => {
+    expect(
+      completeRelativeUrls('![](image.svg)', README_FILEPATH, true, 'svg')
+    ).toEqual(`![](${EXPECTED_RAW_URL}/image.svg)`)
+  })
+
+  test('image with a title', async () => {
+    expect(
+      completeRelativeUrls(
+        '![alttext](image.svg "the image (a title)")',
+        README_FILEPATH,
+        true,
+        'svg'
+      )
+    ).toEqual(`![alttext](${EXPECTED_RAW_URL}/image.svg "the image (a title)")`)
+  })
+
+  test('image with relative link', async () => {
+    expect(
+      completeRelativeUrls(
+        '[![alttext](image.svg)](image.svg)',
+        README_FILEPATH,
+        true,
+        'svg'
+      )
+    ).toEqual(
+      `[![alttext](${EXPECTED_RAW_URL}/image.svg)](${EXPECTED_BLOB_URL}/image.svg)`
+    )
+  })
+
+  test('image with a title, unicode and relative link', async () => {
+    expect(
+      completeRelativeUrls(
+        '[![alttext with 🌬](image.🌬.svg "the image.🌬.svg (a title)")](image.🌬.svg)',
+        README_FILEPATH,
+        true,
+        'svg'
+      )
+    ).toEqual(
+      `[![alttext with 🌬](${EXPECTED_RAW_URL}/image.🌬.svg "the image.🌬.svg (a title)")](${EXPECTED_BLOB_URL}/image.🌬.svg)`
+    )
+  })
+
+  test('image from absolute source with relative link', async () => {
+    expect(
+      completeRelativeUrls(
+        '[![alttext](https://example.com/image.svg)](image.svg)',
+        README_FILEPATH,
+        true,
+        'svg'
+      )
+    ).toEqual(
+      `[![alttext](https://example.com/image.svg)](${EXPECTED_BLOB_URL}/image.svg)`
+    )
+  })
+
+  test('image with absolute link', async () => {
+    expect(
+      completeRelativeUrls(
+        '[![alttext](image.svg)](https://example.com/image.svg)',
+        README_FILEPATH,
+        true,
+        'svg'
+      )
+    ).toEqual(
+      `[![alttext](${EXPECTED_RAW_URL}/image.svg)](https://example.com/image.svg)`
+    )
+  })
+})