api-blueprint-visitors

A Visitor base class that lets you derive your own visitors for manipulating API-Blueprint's AST, so that you can build awesome tools.

Usage no npm install needed!

<script type="module">
  import apiBlueprintVisitors from 'https://cdn.skypack.dev/api-blueprint-visitors';
</script>

README

API Blueprint Visitor

A Visitor base class that lets you derive your own visitors for manipulating API-Blueprint's AST, so that you can build awesome tools.

Installing

npm install api-blueprint-visitors

Getting Started

Two things are provided in api-blueprint-visitors:

  • A Visitor base class
  • The makeASTVisitable function, that makes Protagonist's AST visitable.

Let's imagine we want to create a script that counts all the Resources, Requests and Responses in a blueprint file.

Our visitor could look something like this:

class CounterVisitor extends Visitor {
  constructor() {
    this.resources = 0;
    this.requests = 0;
    this.responses = 0;
  }

   // Each `visit` method is called when the visitor visits the corresponding node.

  visitResource(/*node, ctx*/) {
    this.resources++;
  }

  visitRequest(/*node, ctx*/) {
    this.requests++;
  }

  visitResponse(/*node, ctx*/) {
    this.responses++;
  }

  // Once all the AST has been traversed, `postVisit` is called.
  postVisit() {
    console.log(this.resources);
    console.log(this.requests);
    console.log(this.responses);
  }
}

Now, in order to visit the AST, we need to make that AST visitable:

fs.readFile('blueprint.md', 'utf8', function (err, data) {
    protagonist.parse(data, function(error, result) {
      let ast = result.ast,
        myVisitor = new CounterVisitor();

      makeASTVisitable(ast);

      // Now the AST has an `accept` method:
      ast.accept(myVisitor);
    });
});

And that's it! The visitor can visit Group, Resource, Action, Request, Response and Example.

Check the full example here.

Contributing

  1. Fork it
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request

License

MIT