Loopback-next: Cannot migrate database schema Error: The connector has not been initialized.

[praneshvrp1396]

Have created a datasource and all my db operations are working fine. But I am unable to run migrate script. I am getting the error as Cannot migrate database schema Error: The connector has not been initialized.
I attach my config.json for the datasource below.

{
  "name": "postgres",
  "connector": "postgresql",
  "url": "postgres://postgres:postgres@localhost:5433/doc_patient_link",
  "host": "localhost",
  "port": 5433,
  "user": "postgres",
  "password": "postgres",
  "database": "doc_patient_link",
  "debug":true
}

[achrinza]

Hi @praneshvrp1396, as per-bug report template, could you please provide a reproduction sandbox on GitHub so that we can better spot the issue?

[praneshvrp1396]

Steps to reproduce

Discover a model from a created Datasource.

Edit the existing migrate.ts as:

import { SampleDataSource } from './datasources'
export async function migrate(args: string[]) {
  const ds =  new SampleDataSource();
  await ds.autoupdate('Coupon')
  process.exit(0);
}

Run npm run migrate

Current Behavior

D:\FoxSense\pranesh-ba\birth-assist-server>npm run migrate

> [email protected] migrate D:\FoxSense\pranesh-ba\birth-assist-server
> node ./dist/migrate

Cannot migrate database schema Error: Cannot migrate models not attached to this
 datasource: Coupon
    at D:\FoxSense\pranesh-ba\birth-assist-server\node_modules\loopback-datasour
ce-juggler\lib\datasource.js:1146:12
    at processTicksAndRejections (internal/process/task_queues.js:76:11)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] migrate: `node ./dist/migrate`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] migrate script.
npm ERR! This is probably not a problem with npm. There is likely additional log
ging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\siva1\AppData\Roaming\npm-cache\_logs\2020-02-20T12_54_45_
112Z-debug.log

Expected Behavior

Schema Migration sucessfull

[achrinza]

@praneshvrp1396 Thanks for the extra info;

Taken from the Todo example, migrate.ts should look similar to this (using Application instead of juggler.Datasource directly):

// Copyright IBM Corp. 2018,2019. All Rights Reserved.
// Node module: @loopback/example-todo
// This file is licensed under the MIT License.
// License text available at https://opensource.org/licenses/MIT

import {TodoListApplication} from './application';

export async function migrate(args: string[]) {
  const existingSchema = args.includes('--rebuild') ? 'drop' : 'alter';
  console.log('Migrating schemas (%s existing schema)', existingSchema);

  const app = new TodoListApplication();
  await app.boot();
  await app.migrateSchema({existingSchema});

  // Connectors usually keep a pool of opened connections,
  // this keeps the process running even after all work is done.
  // We need to exit explicitly.
  process.exit(0);
}

migrate(process.argv).catch(err => {
  console.error('Cannot migrate database schema', err);
  process.exit(1);
});

[praneshvrp1396]

Thanks for the response. I replicated the same and I am getting the below error when I run npm run migrate

> [email protected] migrate D:\FoxSense\pranesh-ba\birth-assist-server
> node ./dist/migrate

Cannot migrate database schema error: syntax error at or near "null"
    at Connection.parseE (D:\FoxSense\pranesh-ba\birth-assist-server\node_module
s\pg\lib\connection.js:614:13)
    at Connection.parseMessage (D:\FoxSense\pranesh-ba\birth-assist-server\node_
modules\pg\lib\connection.js:413:19)
    at Socket.<anonymous> (D:\FoxSense\pranesh-ba\birth-assist-server\node_modul
es\pg\lib\connection.js:129:22)
    at Socket.emit (events.js:223:5)
    at addChunk (_stream_readable.js:309:12)
    at readableAddChunk (_stream_readable.js:290:11)
    at Socket.Readable.push (_stream_readable.js:224:10)
    at TCP.onStreamRead (internal/stream_base_commons.js:181:23) {
  name: 'error',
  length: 93,
  severity: 'ERROR',
  code: '42601',
  detail: undefined,
  hint: undefined,
  position: '81',
  internalPosition: undefined,
  internalQuery: undefined,
  where: undefined,
  schema: undefined,
  table: undefined,
  column: undefined,
  dataType: undefined,
  constraint: undefined,
  file: 'scan.l',
  line: '1150',
  routine: 'scanner_yyerror'
}
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] migrate: `node ./dist/migrate`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] migrate script.
npm ERR! This is probably not a problem with npm. There is likely additional log
ging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\siva1\AppData\Roaming\npm-cache\_logs\2020-02-20T15_15_14_
618Z-debug.log

[achrinza]

This might be related: https://github.com/strongloop/loopback-connector-postgresql/issues/34

[praneshvrp1396]

Got this fixed.
I tried migrating from a existing db which I created via pgadminwhere I did not fill the length property of the character varying type. This lead to all confusions.