Mapbox GL JS has API documentation and examples.

Writing API Documentation

API documentation is written as JSDoc comments and processed with documentationjs.

• Classes, methods, events, and anything else in the public interface must be documented with JSDoc comments. Everything outside of the public interface may be documented and must be tagged as @private.
• Text within JSDoc comments may use markdown formatting. Code identifiers must be surrounded by `backticks`.
• Documentation must be written in grammatically correct sentences ending with periods.
• Documentation must specify measurement units when applicable.
• Documentation descriptions must contain more information than what is obvious from the identifier and JSDoc metadata.
• Class descriptions should describe what the class is, or what its instances are. They do not document the constructor, but the class. They should begin with either a complete sentence or a phrase that would complete a sentence beginning with "A T is..." or "The T class is..." Examples: "Lists are ordered indexed dense collections." "A class used for asynchronous computations."
• Function descriptions should begin with a third person singular present tense verb, as if completing a sentence beginning with "This function..." If the primary purpose of the function is to return a value, the description should begin with "Returns..." Examples: "Returns the layer with the specified id." "Sets the map's center point."
• @param, @property, and @returns descriptions should be capitalized and end with a period. They should begin as if completing a sentence beginning with "This is..." or "This..."
• Functions that do not return a value (return undefined), should not have a @returns annotation.
• Member descriptions should document what a member represents or gets and sets. They should also indicate whether the member is read-only.
• Event descriptions should begin with "Fired when..." and so should describe when the event fires. Event entries should clearly document any data passed to the handler, with a link to MDN documentation of native Event objects when applicable.

Writing Examples

Examples are written as Jekyll posts in docs/_posts/examples. The Jekyll front matter should include the following items:

• layout: example
• category: example
• title: A short title for the example in sentence case as a verb phrase
• description: A one sentence description of the example

In the post body, write the HTML and JavaScript constituting the example.

• Use 4 space indentation. Exception: do not add an initial level of indentation to code within <script> tags (it should start flush left).
• Do not include an access token in the example code. The access token will be inserted automatically by the template, using the current logged in user's default public token, or a placeholder <insert token here> string if the user is not logged in.
• Do not use custom styles from your personal account. Use only the default mapbox account styles.
• When embedding literal JSON (GeoJSON or Mapbox style snippets) into script code, double-quote property names and string values. Elsewhere, use single-quoted strings.

Running the Documentation Server Locally

To start a documentation server locally run

npm run start-docs

You can view the documentation at

open http://127.0.0.1:4000/mapbox-gl-js

Troubleshooting

Ensure you have the right version of all dependencies

npm install

Ensure you are running Jekyll version 3.2.x

jekyll -v
 > jekyll 3.2.1

Committing and Publishing Documentation

The mapbox-gl-js repository has both master and mb-pages as active branches. The master branch is used for mainline code development: the next version of mapbox-gl-js will come from the code in this branch, and it may contain documentation and examples for APIs that are not yet part of a public release. The mb-pages branch is published to https://www.mapbox.com/mapbox-gl-js/ on any push to the branch. For the purposes of documentation changes, use these two branches as follows:

• If your changes are relevant to the currently released version, make them on mb-pages. Examples: correcting the API documentation for a released API, adding a new example that depends only on current APIs.
• If your changes depend on gl-js features not in the currently released version, make them on master. Examples: documenting or adding an example for a newly-added API.

When releasing, the release manager will:

• Merge mb-pages to master, ensuring that any accumulated changes in mb-pages propagate to master
• Make the release
• Fast-forward mb-pages to the current master, ensuring that all accumulated changes are published to mapbox.com