remark plugin to validate that Markdown links and images reference
existing local files and headings.
It does not check external URLs (see remark-lint-no-dead-urls
for that).
For example, this document does not have a heading named Hello
.
So if we link to that ([welcome](#hello)
), this plugin will warn about it.
In addition, when I link to a heading in another document
(examples/foo.md#hello
), if this file exists but the heading does not, or if
the file does not exist, this plugin will also warn.
Linking to other files, such as license
or index.js
(when they exist) is
fine.
Table of Contents
Install
npm:
npm install remark-validate-links
Use
CLI
Use remark-validate-links
together with remark:
npm install --global remark-cli remark-validate-links
Let’s say readme.md
is this document, and example.md
looks as follows:
# Hello
Read more [whoops, this does not exist](#world).
This doesn’t exist either [whoops!](readme.md#foo).
But this does exist: [LICENSE](LICENSE).
So does this: [README](readme.md#installation).
Now, running remark -u validate-links .
yields:
example.md
3:11-3:48 warning Link to unknown heading: `world` missing-heading remark-validate-links
5:27-5:51 warning Link to unknown heading in `readme.md`: `foo` missing-heading-in-file remark-validate-links
readme.md: no issues found
⚠ 2 warnings
API
Note: The API only checks links to headings.
Other URLs are not checked.
Say we have the following file, example.md
:
# Alpha
This [exists](#alpha). This [exists][alpha] too.
This [one does not](#does-not).
# Bravo
This is [not checked](readme.md#bravo).
[alpha]: #alpha
And our script, example.js
, looks as follows:
var vfile = require('to-vfile')
var report = require('vfile-reporter')
var remark = require('remark')
var links = require('remark-validate-links')
remark()
.use(links)
.process(vfile.readSync('example.md'), function(err, file) {
console.error(report(err || file))
})
Now, running node example
yields:
example.md
4:6-4:31 warning Link to unknown heading: `does-not` remark-validate-links remark-validate-links
⚠ 1 warning
Configuration
You can pass a repository
, containing anything package.json
s
repository
can handle.
If this is not given, remark-validate-links
will try the package.json
in
the current working directory.
remark --use 'validate-links=repository:"foo/bar"' example.md
When a repository is given or detected (supporting GitHub, GitLab, and
Bitbucket), links to the files are normalized to the file system.
For example, https://github.com/foo/bar/blob/master/example.md
becomes
example.md
.
You can define this repository in configuration files too.
An example .remarkrc
file could look as follows:
{
"plugins": [
[
"validate-links",
{
"repository": "foo/bar"
}
]
]
}
Integration
remark-validate-links
can detect anchors on nodes through several properties
on nodes:
node.data.hProperties.name
— Used by remark-html
to create a name
attribute, which anchors can link tonode.data.hProperties.id
— Used by remark-html
to create an id
attribute, which anchors can link tonode.data.id
— Used, in the future, by other tools to signal
unique identifiers on nodes
Related
Contribute
See contributing.md
in remarkjs/.github
for ways
to get started.
See support.md
for ways to get help.
This project has a Code of Conduct.
By interacting with this repository, organisation, or community you agree to
abide by its terms.
License
MIT © Titus Wormer