Error when using docker-compose to generate a full-stack application - node.js

Question

The API does not find the DB when using docker compose.
I already configured the DATABA_URL and it doesn't work.
.env file:
JWT_SECRET="palavrasecreta"
NODE_ENV=production
DATABASE_URL=postgres://postgres:1234#db:5432/postgres
docker-compose file:
version: "3"
services:
app-front-end:
build: charllenger-front/.
container_name: front-end-ui
expose:
- 3000
ports:
- 3000:3000
links:
- api
api:
container_name: charllenger-back-end-Api
build: Full-Stack-charlenger-API/.
volumes:
- ./src:/app/src
expose:
- 3001
ports:
- 3001:3001
depends_on:
- db
command: bash -c 'yarn migration:run && yarn dev'
links:
- db
db:
container_name: charllenger-Api-postgres
image: "postgres"
env_file:
- Full-Stack-charlenger-API/.env
expose:
- 5432
ports:
- 5432:5432
DATA SOURCE
import { DataSource } from "typeorm";
require("dotenv").config();
export const AppDataSource = new DataSource({
type: "postgres",
host: "database",
url: process.env.DATABASE_URL,
ssl:
process.env.NODE_ENV === "production"
? { rejectUnauthorized: false }
: false,
synchronize: false,
logging: true,
entities:
process.env.NODE_ENV === "production"
? ["src/entities/*.js"]
: ["src/entities/*.ts"],
migrations:
process.env.NODE_ENV === "production"
? ["src/migrations/*.js"]
: ["src/migrations/*.ts"],
});
AppDataSource.initialize()
.then(() => {
console.log("Data Source Initialized");
})
.catch((err) => {
console.error("Error during data source Initialization", err);
}
);
Migration
import { MigrationInterface, QueryRunner } from "typeorm";
export class initialMigration1673714934213 implements MigrationInterface {
name = 'initialMigration1673714934213'
public async up(queryRunner: QueryRunner): Promise<void> {
await queryRunner.query(`CREATE TABLE "transaction" ("transaction_id" uuid NOT NULL, "value" numeric NOT NULL, "createdAt" TIMESTAMP NOT NULL DEFAULT now(), "debitedAccountAccountId" uuid, "creditedAccountAccountId" uuid, CONSTRAINT "PK_6e02e5a0a6a7400e1c944d1e946" PRIMARY KEY ("transaction_id"))`);
await queryRunner.query(`CREATE TABLE "user" ("user_id" uuid NOT NULL, "username" character varying NOT NULL, "password" character varying NOT NULL, "account" uuid, CONSTRAINT "REL_4ab2df0a57a74fdf904e0e2708" UNIQUE ("account"), CONSTRAINT "PK_758b8ce7c18b9d347461b30228d" PRIMARY KEY ("user_id"))`);
await queryRunner.query(`CREATE TABLE "account" ("account_id" uuid NOT NULL, "balance" double precision NOT NULL, CONSTRAINT "PK_ea08b54a9d7322975ffc57fc612" PRIMARY KEY ("account_id"))`);
await queryRunner.query(`ALTER TABLE "transaction" ADD CONSTRAINT "FK_bbbfcdb3330cc4e5846f2d23200" FOREIGN KEY ("debitedAccountAccountId") REFERENCES "account"("account_id") ON DELETE NO ACTION ON UPDATE NO ACTION`);
await queryRunner.query(`ALTER TABLE "transaction" ADD CONSTRAINT "FK_4ece0117a7c2689832bab37209b" FOREIGN KEY ("creditedAccountAccountId") REFERENCES "account"("account_id") ON DELETE NO ACTION ON UPDATE NO ACTION`);
await queryRunner.query(`ALTER TABLE "user" ADD CONSTRAINT "FK_4ab2df0a57a74fdf904e0e27086" FOREIGN KEY ("account") REFERENCES "account"("account_id") ON DELETE NO ACTION ON UPDATE NO ACTION`);
}
public async down(queryRunner: QueryRunner): Promise<void> {
await queryRunner.query(`ALTER TABLE "user" DROP CONSTRAINT "FK_4ab2df0a57a74fdf904e0e27086"`);
await queryRunner.query(`ALTER TABLE "transaction" DROP CONSTRAINT "FK_4ece0117a7c2689832bab37209b"`);
await queryRunner.query(`ALTER TABLE "transaction" DROP CONSTRAINT "FK_bbbfcdb3330cc4e5846f2d23200"`);
await queryRunner.query(`DROP TABLE "account"`);
await queryRunner.query(`DROP TABLE "user"`);
await queryRunner.query(`DROP TABLE "transaction"`);
}
}
Error:
enter image description here
t's working on another computer, I've already changed localhost to db, I've tried other ports and it doesn't work.

Answer 1

In the docker-compose you define your database container as db.
db:
container_name: charllenger-Api-postgres
image: "postgres"
db: is the servicename.
If you want to connect from your api to the database container, inside your docker network, you need to use this servicename as db_host.
the section:
ports:
- 5432:5432
means: map the port 5432 inside the container to my host (your Pc where you installed docker).
So you can access the container on his port 5432, from your PC with localhost:5432 and this works fine if you execute your code localy even if postgres is running inside a container.
If your code runs in a container localhost refers to that container.
Lets say each container has it own localhost. So you can access the other containers only by its servicename. There are a few other possibilities, but lets remain to use the servicename.
In side your Typeorm configuration ensure that the connection to the database use the servicename when you run the code inside the conatiner, or localhost if you run it directly on your pc without docker.
When you deploy it to Production, again you must look where the db_host is. That depends on your deployment. If you use an external DB from a provvider it should be a full qualified domain name. If you deploy your db by yourself it depends if you use docker Kubernetes or what else.