CODEWITHSUNDEEP
javascriptnode.jsmoduletypescript
RaceBase
RaceBase

Reputation: 18848

Typescript working with Modules

I am trying to build my first simple ORM based Node JS Application.

I created Database module like this

import * as Knex from 'knex';
import * as Bookshelf from 'bookshelf';

module Database {
    class Config {
        private static _knex: Knex = Knex({
            client: 'mysql',
            connection: {
                host: '127.0.0.1',
                user: 'root',
                password: '',
                database: 'test',
                charset: 'utf8'
            }
        });

        static _bookshelf: Bookshelf = Bookshelf(Config._knex);
    }

    export function bookshelf() {
        Config._bookshelf.plugin('registry');
        Config._bookshelf.plugin(['virtuals']);
        return Config._bookshelf;
    }
}

And I am trying to use it in one of the DAO classes

/// <reference path="../models/usermodel.ts" />
/// <reference path="../network/database.ts" />
module DAO {
    export class UserDAO {
        create(user: Model.User): Model.User { //Model.User is imported nicely
            var test = Database.bookshelf(); //what's wrong with this
            return null;
        }
    }
}

which is ending up with this error dao/userdao.ts(18,24): error TS2304: Cannot find name 'Database'.

It's my first learning towards Typescript and Modules, let me know if I am doing something wrong.

Update: As soon as I add import statements in database.ts, It's not working/can't find name. What I am doing wrong by using import * as something from some

Upvotes: 1

Views: 600

Answers (1)

Relu Mesaros
Relu Mesaros

Reputation: 5038

// database.ts
/// <reference path="<pathToKnexDefinetelyTypedFile>" />
// if you don't already have knex.d.ts
// https://raw.githubusercontent.com/DefinitelyTyped/DefinitelyTyped/master/knex/knex.d.ts
/// <reference path="<pathToBookshelfDefinetelyTypedFile>" />
// if you don't already have bookshelf.d.ts
// https://raw.githubusercontent.com/DefinitelyTyped/DefinitelyTyped/master/bookshelf/bookshelf.d.ts

// normally these references are unnecessary, but you have 
// to download all the ts for third libraries 
// you normally place them in a 'typings' folder 
// or choose another name for the folder, irrelevant,
// then the IDE should recognize them (ts files) easily.

import * as Knex from 'knex';
import * as Bookshelf from 'bookshelf';

module Database {
    class Config {
        private static _knex: Knex = Knex({
            client: 'mysql',
            connection: {
                host: '127.0.0.1',
                user: 'root',
                password: '',
                database: 'test',
                charset: 'utf8'
            }
        });

        static _bookshelf: Bookshelf = Bookshelf(Config._knex);
    }

    export function bookshelf() {
        Config._bookshelf.plugin('registry');
        Config._bookshelf.plugin(['virtuals']);
        return Config._bookshelf;
    }
}

// Don't forget the export, that why you are getting that error
export { Database }

// dao.ts
/// <reference path="../models/usermodel.ts" />
/// <reference path="../network/database.ts" />
import { Database } from './database';
module DAO {
    export class UserDAO {
        create(user: Model.User): Model.User { //Model.User is imported nicely
            var test = Database.bookshelf(); 
            // what's wrong with this ? 
            // Maybe the export and the import you forgot to add 
            return null;
        }
    }
}

The reference comment is used only by typescript, they don't get transpiled, you won't see them in the generated js. The reference comment is unnecessary if your IDE recognizes all the ts files in the project.

You have to import/export namespaces/modules that you use in current files, that's because imports/exports are transpiled, they will be compiled in js, you will see them in the generated js

Upvotes: 2

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