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Question

I am creating an app with typescript express node typeorm. I am having this issue where when I make a call through a service class to the database using typeorm, I get connection default was not found. Here are my code snippets:

//dataservice class
import { Connection, getConnection, EntityManager, Repository, 
getManager } from "typeorm";

export class LeaveDataService {
private _db: Repository<Leave>;

constructor() {
    this._db = getManager().getRepository(Leave);
}

/**
 * applyForLeave
 */
public applyForLeave(leave: Leave): void {
    if(leave !== null) {
        let entity: Leave  = this._db.create(leave);
        this._db.save(entity);
    }
}

/**
 * getAllLeaves
 */
public async getAllLeaves(): Promise<Array<Leave>> {
    let leaves: Promise<Array<Leave>> = this._db.find({
        select: ["leaveDays","casualLeaveDays","id","staff","leaveType","endorsedBy","approvedBy"],
        relations: ["staff", "leaveType"],
        skip: 5,
        take: 15
    });

    return leaves;
}

this is my ormconfig.json

{
    "type":"sqlite",
    "entities": ["./models/*.js"],
    "database": "./leaveappdb.sql"
}

and this is the "controller" that responds to requests by calling the service class which is the first snippet:

import { Request, Response } from "express";
import { LeaveDataService } from "../services/leaveDataService";
import { LeaveIndexApiModel } from '../ApiModels/leaveIndexApiModel';



const dataService: LeaveDataService = new LeaveDataService();

export let index = async (req: Request, res: Response) => {
let result = await dataService.getAllLeaves();
let viewresult = new Array<LeaveIndexApiModel>();

result.forEach(leave => {
    let apmodel = 
    new LeaveIndexApiModel(leave.leaveType.name, 
`${leave.staff.firstname} ${leave.staff.lastname}`, leave.id);
    viewresult.push(apmodel);
});


return res.status(200).send(viewresult);
}

then this is where I bootstrap my app.

import express = require('express');
import bodyParser = require('body-parser');
import path = require('path');
import * as home from './controllers/home';
import { createConnection } from 'typeorm';
import * as leavectrl from "./controllers/leaveController";
//create express server


//create app db connection.
createConnection().then(async connection => {
const app = express();
console.log("DB online!");
const approot = './';
const appport = process.env.Port || 8001;
//setup express for json parsing even with urlencoding
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(express.static(path.join(approot,'dist')));

//serve and respond to routes by api
app.get('/home', home.home);
app.get('/login',home.login);

//routes for leave
app.get('/api/leaves', leavectrl.index);
//default fall through
// app.get('*', (req: Request, res: Response)=>{
//     res.sendFile(approot,'dist/index.html');
// });

app.listen(appport, ()=> console.log(`api is alive on port 
${appport}`));

}).catch(error => console.log("Data Access Error : ", error));

Answer 1

Your configuration is seems to be good but you didn't called or used your ormconfig.json file to createConnection.

for Eg:

createConnection(./ormconfig.json).then(async connection => {
}).catch(error => console.log("Data Access Error : ", error));

Try with or i will give you a way to configure with class object to establish a DB connection

In config file:

import "reflect-metadata";
import { ConnectionOptions } from "typeorm";
import { abc } from "../DatabaseEntities/abc";
import { def } from '../DatabaseEntities/def';

export let dbOptions: ConnectionOptions = {
            type: "sqlite",
            name: app,
            database: "./leaveappdb.sqlite3", 
            entities: [abc, def],
            synchronize: true,
} 

In server.ts

import { createConnection, createConnections } from 'typeorm';
import * as appConfig from './Config/config';
createConnection(appConfig.dbOptions).then(async connection => {
    console.log("Connected to DB");
}).catch(error => console.log("TypeORM connection error: ", error));

I think this may help you..

Also, i have found that for connecting sqlite DB you are trying to connect a sql file. Kindly confirm that once too.

Thank you