A progressive Node.js framework for building efficient and scalable server-side applications.

Description

PostgreSQL module for Nest framework (node.js) 😻

Installation

First install the module via yarn or npm or pnpm and do not forget to install the driver package as well:

    $ npm i --save nest-postgres pg

or

    $ yarn add nest-postgres pg

or

    $ pnpm add nest-postgres pg

Table of Contents

• Description
• Table of Contents
• Usage
  • PostgresModule
  • MultiConnectionsDatabase
  • ExampleOfUse

Usage

PostgresModule

PostgresModule is the primary entry point for this package and can be used synchronously

@Module({
  imports: [
    PostgresModule.forRoot({
        connectionString: 'postgresql://[user]:[password]@[host]/[nameDb]',
        // or 
        // host: 'localhost',
        // database: [:databaseName],
        // password: [:passwordDb],
        // user: [:userDb],
        // port: 5432,
    }),
  ],
})

or asynchronously

@Module({
  imports: [
    PostgresModule.forRootAsync({
      useFactory: () => ({
        connectionString: 'postgresql://[user]:[password]@[host]/[nameDb]',
        // or 
        // host: 'localhost',
        // database: [:databaseName],
        // password: [:passwordDb],
        // user: [:userDb],
        // port: 5432,
      }),
    }),
  ],
})

Example of use

UsersService:

import { Client } from 'pg';
import { InjectClient } from 'nest-postgres';

@Injectable()
export class UsersService {
  constructor(@InjectClient() private readonly pg: Client) {}

  public async findAll(): Promise<User[]> {
    const users = await this.pg.query('SELECT * FROM users');
    return users.rows;
  }
}

UsersController:

import { Controller, Get } from '@nestjs/common';
import { UsersService } from './users.service';

@Controller()
export class UsersController {
  constructor(private readonly usersService: UsersService) {}

  @Get()
  async getAllUsers(): Promise<User[]> {
    return await this.usersService.findAll();
  }
}

Multi Connections Database

@Module({
  imports: [
    PostgresModule.forRoot(
      {
        connectionString: 'postgresql://postgres:pass123@localhost:5432/nest1',
        // or 
        // host: 'localhost',
        // database: [:databaseName],
        // password: [:passwordDb],
        // user: [:userDb],
        // port: 5432,
      },
      'db1Connection',
    ),
    PostgresModule.forRoot(
      {
        connectionString: 'postgresql://postgres:pass123@localhost:5434/nest2',
      },
      'db2Connection',
    ),
  ],
  controllers: [],
  providers: [],
})
export class AppModule {}

Usage example with Multi Connection

PostService:

import { Client } from 'pg';
import { InjectConnection } from 'nest-postgres';
import { CreatePostDto } from './dto/create-post.dto';
import { Post } from './interfaces/post.interface';

@Injectable()
export class PostService {
  constructor(
    @InjectConnection('db2Connection')
    private dbConnection: Client,
  ) {}

  public async findAll(): Promise<Post[]> {
    const users = await this.dbConnection.query('SELECT * FROM posts');
    return users.rows;
  }

  public async create(createPostDto: CreatePostDto): Promise<Post[]> {
    try {
      const user = await this.dbConnection.query(
        'INSERT INTO posts (title, description)  VALUES ($1, $2) RETURNING *',
        [createPostDto.title, createPostDto.description],
      );
      return user.rows;
    } catch (err) {
      throw new HttpException(err, HttpStatus.BAD_REQUEST);
    }
  }
}

UsersService:

import { Client } from 'pg';
import { InjectConnection } from 'nest-postgres';
import { CreateUserDto } from './dto/create-user.dto';
import { User } from './interfaces/user.interface';

@Injectable()
export class UsersService {
  constructor(
    @InjectConnection('db1Connection')
    private dbConnection: Client,
  ) {}

  public async findAll(): Promise<User[]> {
    const users = await this.dbConnection.query('SELECT * FROM users');
    return users.rows;
  }

  public async create(createUserDto: CreateUserDto): Promise<User[]> {
    try {
      const user = await this.dbConnection.query(
        'INSERT INTO users (firstName, lastName)  VALUES ($1, $2) RETURNING *',
        [createUserDto.firstName, createUserDto.lastName],
      );
      return user.rows;
    } catch (err) {
      throw new HttpException(err, HttpStatus.BAD_REQUEST);
    }
  }
}

For more information on node-postgres for Nodejs see here

Contribute

Feel free to help this library, I'm quite busy with also another Nestjs packages, but the community will appreciate the effort of improving this library. Make sure you follow the guidelines

Stay in touch

• Author - Tony133
• Framework - https://nestjs.com

License

MIT licensed