plantuml-parser

Parse PlantUML with JavaScript or TypeScript

The aim of this project is to provide a feature-complete, well tested and maintainable Parsing Expression Grammar (PEG) for the PlantUML syntax. The parser is designed to be used as JavaScript library or from the Command Line.

Important: The parser is not yet feature-complete. But we focus on writing a robust implementation which can parse parts of diagrams without knowing the full syntax. This means that the parser probably still parses just about enough to get you started. If not, please contribute ❤️.

Installation

$ npm install --save plantuml-parser

Examples / Fixtures

PlantUML is not a formally defined language - something we would like to change. This means we have to build this parser by reverse engineering from examples. For this reason we keep a large set of PlantUML diagrams (in.plantuml) and the corresponding formatted output (parse[File]-out.<formatter>) in test/fixtures/. We even have diagrams which exposed bugs in the parser or diagrams which contain known broken PlantUML syntax. Please help us expand that collection by contributing your own diagrams. Every diagram counts 🚀.

Usage

const { parse, parseFile, formatters } = require('plantuml-parser');

// Example PlantUML
const data = `
@startuml
  class A
  class B
  A --|> B
@enduml
`;

// parse PlantUML
const result = parse(data);

// Format and print parse result
console.log(
  formatters.default(result)
);

Output

[
  {
    "elements": [
      {
        "name": "A",
        "title": "A",
        "isAbstract": false,
        "members": [],
        "extends_": [],
        "implements_": [],
        "generics": [],
        "stereotypes": []
      },
      {
        "name": "B",
        "title": "B",
        "isAbstract": false,
        "members": [],
        "extends_": [],
        "implements_": [],
        "generics": [],
        "stereotypes": []
      },
      {
        "left": "A",
        "right": "B",
        "leftType": "Unknown",
        "rightType": "Unknown",
        "leftArrowHead": "",
        "rightArrowHead": "|>",
        "leftArrowBody": "-",
        "rightArrowBody": "-",
        "leftCardinality": "",
        "rightCardinality": "",
        "label": "",
        "hidden": false
      }
    ]
  }
]

parse(data, options)

Parse PlantUML in data. Returns the parse result.

• data: data to parse
• options: supports all PEG.js parser options. Enable tracing with options.verbose = true. If tracing is enabled, options is also forwarded to the tracer object. See pegjs-backtrace options for a full list of supported tracer options.

parseFile(pattern, options, cb)

Parse all PlantUML diagrams in the files matching pattern. If given, the callback function cb will make this function behave asynchronous.

• pattern: files to parse, supports globbing, e.g.: **/*.plantuml.
• options: supports all PEG.js parser options. Enable tracing with options.verbose = true. If tracing is enabled, options is also forwarded to the tracer object. See pegjs-backtrace options for a full list of supported tracer options.
• cb: (optional) asynchronous callback. Called with: cb(err, result)

formatters: A collection of built-in parse result formatters.

For a detailed description of all the formatters see src/formatters.

Command Line Interface

Installation

# npm install --global plantuml-parser

Usage

Options:
  --version        Show version number                                 [boolean]
  --formatter, -f  formatter to use
                              [choices: "default", "graph"] [default: "default"]
  --input, -i      input file(s) to read, supports globbing
                                                       [string] [default: stdin]
  --output, -o     output file to write               [string] [default: stdout]
  --color, -c      colorful output                    [boolean] [default: false]
  --verbose, -v    1x print verbose output, 2x print parser tracing
                                                            [count] [default: 0]
  --help           Show help                                           [boolean]

Features

• Diagram Types:
  • Class
  • Component
  • Use Case
  • Sequence
  • Activity
  • State
  • Object
  • Deployment
  • Timing
• Support for StdLibs:
  • C4 (v2.4.0)
• Formatters:
  • JSON
  • Graph
• Testing, CI/CD:
  • Fixtures for all formatters
  • Code coverage
  • Code formatting
  • Code linting
  • Error case testing
  • Dependency audit
• Misc
  • Typescript support
  • Fully typed parser result
  • Internally typed parser

Test

$ npm test

This will run:

• unit tests
• code coverage
• eslint

Contribute ❤️

Every contribution counts. Please,

• ... submit unparsable diagrams via new issue.
• ... extend the parser by forking and creating a Pull Request

When contributing code, always also update the fixtures and run tests.

$ npm run fixtures
$ npm test
$ git commit

For more information see our contribution guidelines.

Related

• PEG.js: Parser Generator for JavaScript
• ts-pegjs: Plugin for pegjs to generate TypeScript parsers
• PlantUML code generator: Provides a command line utility to generate code in various languages given a PlantUML class diagram.

License

• Apache 2.0