*nix Programming Mammals

    servicemanager
    TypeScript icon, indicating that this package has built-in type declarations

    0.13.5 • Public • Published

    🔌 ServiceManager

    build status npm version npm download dependencies coverage status license

    What is the ServiceManager?

    ServiceManager is probably the most basic implementation of dependency injection container for JavaScript.

    Quick start

    Execute npm install servicemanager or yarn add servicemanager to install servicemanager and its dependencies into your project directory.

    Usage

    Basics (Hooks Way)

    To register objects to service manager, create a file/module for your service context:

    //
    // serviceContext.js
    //
    import { createContext, factory, singleton } from 'servicemanager';
     
    const context = createContext(
        [ 'ResourceManager', factory(DefaultResourceManager) ],
        [ 'CacheManager', factory(CustomCacheManager) ],
        [ 'SessionManager', singleton(mySessionManager) ]
    );

    To get objects back from service manager:

    //
    // anotherFile.js
    //
    import useServiceManager from 'servicemanager';
     
    // get default service context
    const context = useServiceManager();
     
    // returns a new instance for DefaultResourceManager
    const resourceManager = context.get('ResourceManager');
     
    // returns a new instance for CustomCacheManager
    const cacheManager = context.get('CacheManager');
     
    // returns the same session manager object that referenced by mySessionManager
    const sessionManager = context.get('SessionManager');

    Alternatively, to get all needed instances at once:

    //
    // anotherFile2.js
    //
    import useServiceManager from 'servicemanager';
     
    // get default service context
    const context = useServiceManager();
     
    const [ resourceManager, cacheManager, sessionManager ] = context.getRange('ResourceManager', 'CacheManager', 'SessionManager');

    ...Or, to have them in more promise-friendly way:

    //
    // anotherFile3.js
    //
    import useServiceManager from 'servicemanager';
     
    // get default service context
    const context = useServiceManager();
     
    context.ensure([ 'ResourceManager', 'CacheManager', 'SessionManager' ], (resourceManager, cacheManager, sessionManager) => {
        // awaits promisified generator functions first,
        // then services dependencies as parameters
    });

    *** Note: Service names can be anything including objects, symbols or strings.

    Basics (Functional Way)

    To register objects to service manager, create a file/module for your service context:

    //
    // serviceContext.js
    //
    import { createContext, factory, singleton } from 'servicemanager';
     
    const context = createContext(
        [ 'ResourceManager', factory(DefaultResourceManager) ],
        [ 'CacheManager', factory(CustomCacheManager) ],
        [ 'SessionManager', singleton(mySessionManager) ]
    );
     
    export {
        context as default,
    };

    To get objects back from service manager:

    //
    // anotherFile.js
    //
    import { get } from 'servicemanager';
    import context from './serviceContext.js';
     
    // returns a new instance for DefaultResourceManager
    const resourceManager = get(context, 'ResourceManager');
     
    // returns a new instance for CustomCacheManager
    const cacheManager = get(context, 'CacheManager');
     
    // returns the same session manager object that referenced by mySessionManager
    const sessionManager = get(context, 'SessionManager');

    Alternatively, to get all needed instances at once:

    //
    // anotherFile2.js
    //
    import { getRange } from 'servicemanager';
    import context from './serviceContext.js';
     
    const [ resourceManager, cacheManager, sessionManager ] = getRange(context, 'ResourceManager', 'CacheManager', 'SessionManager');

    ...Or, to have them in more promise-friendly way:

    //
    // anotherFile3.js
    //
    import { ensure } from 'servicemanager';
    import context from './serviceContext.js';
     
    ensure(context, [ 'ResourceManager', 'CacheManager', 'SessionManager' ], (resourceManager, cacheManager, sessionManager) => {
        // awaits promisified generator functions first,
        // then services dependencies as parameters
    });

    *** Note: Service names can be anything including objects, symbols or strings.

    API

    ServiceContext.prototype methods

    constructor(...definitions: ServiceDefinitions)
    
    get(dependency: any): any
    
    getRange(...dependencies: Array<any>): Array<any>
    
    ensure(dependencies: Array<any>, callback: (...services: Array<any>) => any): Promise<any>
    
    all(): Array<string>
    
    filter(predicate: FilterPredicate): Array<string>
    
    filterByTag(tag: string): Array<string>
    

    Mechanics

    Factory services call generator/dependency target each time they are requested, whereas, Singleton services are registered when they are defined.

    import createContext, { factory, singleton } from 'servicemanager';
     
    const date1 = Symbol('date1');
    const date2 = Symbol('date2');
     
    const context = createContext(
        [ date1, factory(() => new Date()) ],
        [ date2, singleton(new Date()) ]
    );
     
    console.log(context.get(date1)); // calls and returns new Date()
    console.log(context.get(date1)); // calls and returns new Date() again,
    console.log(context.get(date2)); // no calls, returns stored date.

    Todo List

    See GitHub Projects for more.

    Requirements

    • node.js (https://nodejs.org/)

    License

    Apache 2.0, for further details, please see LICENSE file

    Contributing

    See contributors.md

    It is publicly open for any contribution. Bugfixes, new features and extra modules are welcome.

    • To contribute to code: Fork the repo, push your changes to your fork, and submit a pull request.
    • To report a bug: If something does not work, please report it using GitHub Issues.

    To Support

    Visit my patreon profile at patreon.com/eserozvataf

    Install

    npm i servicemanager

    DownloadsWeekly Downloads

    28

    Version

    0.13.5

    License

    Apache-2.0

    Unpacked Size

    61.2 kB

    Total Files

    62

    Last publish

    Collaborators

    • eserozvataf