Contracts-TS Documentation

@jonloucks/contracts-ts

Badges

Typescript Dependency Contracts for dependency inversion

Documentation

Installation

npm install @jonloucks/contracts-ts

Usage - code fragments from Example.test.ts

Importing the Package

import { CONTRACTS, createContract } from '@jonloucks/contracts-ts';

Importing the Convenience Package

import {
  AutoClose,
  bind,
  claim,
  Contract,
  createExtractor,
  createLifeCycle,
  createRepository,
  createSingleton,
  createValue,
  createContract,
  enforce,
  guardFunctions,
  isBound
} from "@jonloucks/contracts-ts/api/Convenience";

Creating a Contract

// Define a service interface
interface Logger {
    log(message: string): void;
}

// Create a contract for the service
const LOGGER_CONTRACT: Contract<Logger> = createContract<Logger>({
    name: "Logger",
    test: (obj: unknown): obj is Logger => { // example of duck-typing check
    return guardFunctions(obj, 'log'); // example of using guardFunctions helper
    }
});

Binding a Contract


bind<Logger>(LOGGER_CONTRACT,
    createSingleton<Logger>(
        () => ({
            log: (message: string) => {
                console.log("LOG:", message);
            }
        })));

Using the Contract

const logger : Logger = enforce<Logger>(LOGGER_CONTRACT);
logger.log("Using the service in the test.");

Development

Install dependencies

npm install

Build the project

npm run build

Run tests

npm test

Run tests in watch mode

npm run test:watch

Run test coverage

npm run test:coverage

Lint the code

npm run lint

Fix linting issues

npm run lint:fix

Generate documents

npm run docs

Generate badges

npm run badges

Project Structure

All tests must have suffix of -test.ts or -spec.ts
Tests that validate supported APIs go in src/test
Tests that validate internal implementation details go in src/impl

contracts-ts
├── .github
│   ├── ISSUE_TEMPLATE
│   │   ├── bug_report.md
│   │   └── feature_request.md
│   └── workflows
│       ├── main-pull-request-matrix.yml
│       ├── main-pull-request.yml
│       ├── main-push.yml
│       └── main-release.yml
├── CODE_OF_CONDUCT.md
├── CODING_STANDARDS.md
├── CONTRIBUTING.md
├── editorconfig
├── eslint.config.mjs
├── jest.config.js
├── LICENSE
├── package-lock.json
├── package.json
├── PULL_REQUEST_TEMPLATE.md
├── README.md
├── scripts
│   ├── badge-template.svg.dat
│   └── tsconfig.json
├── SECURITY.md
├── src
│   ├── index.ts
│   ├── version.ts
│   ├── api
│   │   ├── *.ts
│   │   ├── *.api.ts
│   ├── auxiliary
│   │   ├── *.ts
│   │   ├── *.impl.ts
│   │   ├── *.test.ts    // internal implementation specific
│   │   └── *.api.ts
│   ├── impl
│   │   ├── *.ts
│   │   ├── *.impl.ts
│   │   ├── *.test.ts    // internal implementation specific
│   │   └── *.api.ts
│   ├── test
│   │   └── *.test.ts
│   └── never-publish             // non shippable development scripts
│       ├── *.ts
│       ├── *.*.                  // data files etc
│       └── *.test.ts
├── tsconfig.json
└── typedoc.json

GitHub Workflows

CI Workflow

The CI workflow runs on every push and pull request to main branch. It:

Tests against Node.js versions 18.x, 20.x, 22.x, and 24.x
Runs linting
Builds the project
Runs tests with coverage
Uploads coverage to Codecov (optional)

Publish Workflow

The GitHub publishings workflows are run to make an official release.

If all scanning and tests pass it is published. There is no other way allowed.
Publishing authentication is done using (OIDC trusted publishing)

To set up your own publishing:

Publishing this project as is intentionally disabled
You are welcome to fork this repository and publish where you want.
Run npm pkg delete private to remove the private flag from the package.
Change the name field in package.json to your desired package name.

License

MIT