Context

Request context module for appolo build with appolo-context and async_hooks.

new context will be created for every request

Installation#

npm i @appolo/context

Options#

key	Description	Type	Default
`id`	id of context injector	`string`	`context`

in config/modules/all.ts

import {ContextModule} from '@appolo/context';

export = async function (app: App) {
   app.module.user(ContextModule);
}

Usage#

first define your context using the @context decorator

import {context} from '@appolo/context';
import {inject} from '@appolo/inject';

@context()
export class MyContext {

    @inject() env: any;

    constructor(req, res) {

    }

    private _user: string;

    public set user(value: string) {

        this._user = value
    }

    public get user(): string {
        return this._user
    }
}

For the example we will define a middleware to set the context data

@define()
@singleton()
export class UserMiddleware extends Middleware {
    @inject() context: MyContext;

    async run(req, res, next) {
        this.context.user = req.query.userName;
        next()
    }
}

Now we can access the context from any class using @inject context

note that the context is uniq for every request and cannot share data between requests

@define()
@singleton()
export class SomeManager {

    @inject() context: MyContext ;

    public async getName():Promise<string>{
        return this.context.user;
    }
}

In the controller we will put the middleware and access the manager to get the context name

@controller()
export class ContextController extends Controller {

    @inject() someManager: Manager;

    @get("/test/context/")
    @middleware(UserMiddleware)
    async test(req: IRequest, res: IResponse) {

        let userName = await this.someManager.getName()

        return {userName}
    }
}

You can also access the current context from getContext function

import {getContext} from '@appolo/context';

@define()
@singleton()
export class SomeManager {

    public async getName():Promise<string>{
        return getContext().user;
    }
}