componentsjs-generator

Components-Generator.js

This is a tool to automatically generate .jsonld component files from TypeScript classes for the Components.js dependency injection framework.

Before you use this tool, it is recommended to first read the Components.js documentation.

Getting started

1. Install as a dev dependency

npm install -D componentsjs-generator

or

yarn add -D componentsjs-generator

2. Declare components in package.json

If you are already using Components.js, you already have this.

Add the following entry to package.json:

{
  ...
  "lsd:module": true,
  ...
}

On each line, make sure to replace my-package with your package name.

3. (optional) Add generate script

Call componentsjs-generator as a npm script by adding a scripts entry to your package.json:

{
  ...,
  "scripts": {
    ...
    "build": "npm run build:ts && npm run build:components",
    "build:ts": "tsc",
    "build:components": "componentsjs-generator",
    "prepare": "npm run build",
    ...
  }
}

This is only a recommended way of calling componentsjs-generator, you are free to call it in a different way that better suits your pipeline.

4. (optional) Ignore generated components files

Since we automatically generate the components files, we do not have to check them into version control systems like git. So we can add the following line to .gitignore:

components

If you do this, make sure that the components folder is published to npm by adding the following to your package.json:

{
  ...
  "files": [
    ....
    "components/**/*.jsonld",
    "config/**/*.json",
    ....
  ],
  ....
}

Usage

When invoking componentsjs-generator, this tool will automatically generate .jsonld components files for all TypeScript files that are exported by the current package.

Generates component file for a package
Usage:
  componentsjs-generator
  Options:
       -p path/to/package      The directory of the package to look in, defaults to working directory
       -s lib                  Relative path to directory containing source files, defaults to 'lib'
       -c components           Relative path to directory that will contain components files, defaults to 'components'
       -e jsonld               Extension for components files (without .), defaults to 'jsonld'
       -i ignore-classes.json  Relative path to an optional file with class names to ignore
       --help                  Show information about this command

  Experimental options:
       --typeScopedContexts    If a type-scoped context for each component is to be generated with parameter name aliases

Note: This generator will read .d.ts files, so it is important that you invoke the TypeScript compiler (tsc) before using this tool.

Ignoring classes

If you don't want components to be generated for certain classes, then you can pass a JSON file to the -i option containing an array of class names to skip.

For example, invoking componentsjs-generator -i ignore-classes.json will skip BadClass if the contents of ignore-classes.json are:

[
  "BadClass"
]

If you are looking for a way to ignore parameters, see the @ignored argument tag below.

How it works

For each exported TypeScript class, its constructor will be checked, and component parameters will be generated based on the TypeScript type annotations.

Example

TypeScript class:

/**
 * This is a great class!
 */
export class MyClass extends OtherClass {
  /**
   * @param paramA - My parameter
   */
  constructor(paramA: boolean, paramB: number) {
  
  }
}

Component file:

{
  "@context": [
    "https://linkedsoftwaredependencies.org/bundles/npm/@solid/community-server/^1.0.0/components/context.jsonld"
  ],
  "@id": "npmd:my-package",
  "components": [
    {
      "@id": "ex:MyFile#MyClass",
      "@type": "Class",
      "requireElement": "MyClass",
      "extends": "ex:OtherFile#OtherClass",
      "comment": "This is a great class!",
      "parameters": [
        {
          "@id": "ex:MyFile#MyClass_paramA",
          "range": "xsd:boolean",
          "comment": "My parameter",
          "unique": true,
          "required": true
        },
        {
          "@id": "ex:MyFile#MyClass_paramB",
          "range": "xsd:integer",
          "unique": true,
          "required": true
        }
      ],
      "constructorArguments": [
        { "@id": "ex:MyFile#MyClass_paramA" },
        { "@id": "ex:MyFile#MyClass_paramB" }
      ]
    }
  ]
}

Arguments

Each argument in the constructor of the class must be one of the following:

• A primitive type such as boolean, number, string, which will be mapped to an XSD type
• Another class, which will be mapped to the component @id.
• A hash or interface containing key-value pairs where each value matches one of the possible options. Nesting is allowed.
• An array of any of the allowed types.

Here is an example that showcases all of these options:

import {Logger} from "@comunica/core";
export class SampleActor {
   constructor(args:HashArg, testArray:HashArg[], numberSample: number, componentExample: Logger) {}
}
export interface HashArg {
   args: NestedHashArg;
   arraySample: NestedHashArg[];
}
export interface NestedHashArg extends ExtendsTest {
   test: boolean;
   componentTest: Logger;
}
export interface ExtendsTest {
   stringTest: String;
}

Argument tags

Using comment tags, arguments can be customized.

Tags

Tag	Action
@ignored	This field will be ignored.
@default {<value>}	The default attribute of the parameter will be set to <value>
@range {<type>}	The range attribute of the parameter will be set to <type>. You can only use values that fit the type of field. Options: boolean, int, integer, number, byte, long, float, decimal, double, string. For example, if your field has the type number, you could explicitly mark it as a float by using @range {float}. See the documentation.

Examples

Tagging constructor fields:

TypeScript class:

export class MyActor {
    /**
     * @param myByte - This is an array of bytes @range {byte}
     * @param ignoredArg - @ignored
     */ 
    constructor(myByte: number[], ignoredArg: string) {

    }
}

Component file:

{
  "components": [
    {
      "parameters": [
        {
          "@id": "my-actor#TestClass#myByte",
          "range": "xsd:byte",
          "required": false,
          "unique": false,
          "comment": "This is an array of bytes"
        }
      ],
      "constructorArguments": [
        {
          "@id": "my-actor#TestClass#myByte"
        }
      ]
    }
  ]
}

Tagging interface fields:

TypeScript class:

export class MyActor {
  constructor(args: IActorBindingArgs) {
    super(args)
  }
}

export interface IActorBindingArgs {
  /**
   * This field is very important
   * @range {float}
   * @default {5.0}
   */
   floatField?: number;
}

Component file:

{
  "components": [
    {
      "parameters": [
        {
          "@id": "my-actor#floatField",
          "range": "xsd:float",
          "required": false,
          "unique": true,
          "default": "5.0",
          "comment": "This field is very important"
        }
      ],
      "constructorArguments": [
        {
          "fields": [
            {
              "keyRaw": "floatField",
              "value": "my-actor#floatField"
            }
          ]
        }
      ]
    }
  ]
}

License

Components.js is written by Ruben Taelman.

This code is copyrighted by Ghent University – imec and released under the MIT license.

Changelog

v2.3.0 - 2021-06-08

Added

• Generate interface-based components

<a name="v2.2.0"></a>