typeorm config with .env variables - node.js

Question

i have this ormconfig.json:
{
"type": "postgres",
"host": "db-pg",
"port": 5432,
"username": "spirit",
"password": "api",
"database": "emasa_ci",
"synchronize": true,
"logging": false,
"entities": ["dist/src/entity/**/*.js"],
"migrations": ["dist/src/migration/**/*.js"],
"subscribers": ["dist/src/subscriber/**/*.js"],
"cli": {
"entitiesDir": "dist/src/entity",
"migrationsDir": "dist/src/migration",
"subscribersDir": "dist/src/subscriber"
}
}
and have this env:
SERVER_PORT=4000
DB_HOST=db-pg
DB_PORT=5432
DB_USER=spirit
DB_PASS=api
DB_NAME=emasa_ci
but .env doesn't work in .json and so I don't know how I'm going to use my enviroment variables in my config orm

Answer 1

There is a good documentation.
If you want to dig into the source code - there is a class ConnectionOptionReader, which is looking for file ormconfig (with extensions env, js, cjs, ts, json, yml, yaml, xml) or for file .env. See the load function for more details.
1 So the easiest way is to add a line in your .env file, like this:
TYPEORM_URL=postgres://user:pass#host:port/dbname
Or use this sample. TypeORM will parse .env file using dotenv.
Here you can find all available env varibales.
2 If you read your .env file before TypeORM initialization, you can already use your env variables. For example in a Javascript file, instead ormconfig.json. Just export object like this from the file ormconfig.js:
module.exports = {
"type": "postgres",
"host": process.env.DB_HOST,
"port": process.env.DB_PORT,
"username": process.env.DB_USER,
"password": process.env.DB_PASS,
"database": process.env.DB_NAME,
"synchronize": true,
"logging": false,
"entities": ["dist/src/entity/**/*.js"],
"migrations": ["dist/src/migration/**/*.js"],
"subscribers": ["dist/src/subscriber/**/*.js"],
"cli": {
"entitiesDir": "dist/src/entity",
"migrationsDir": "dist/src/migration",
"subscribersDir": "dist/src/subscriber"
}
};
Another example

Answer 2

Since ormconfig is deprecated, I suggest another approach using TypeORM DataSource.
I'm using Heroku to deploy my server, so I created an environment file containing the same variable as created in Heroku Dynos, named .development.env:
DATABASE_URL="postgres://user:password#localhost:5432/main"
Note that you can place this file anywhere in your project tree.
Then I created a datasource file:
import dotenv from 'dotenv';
import { DataSource } from 'typeorm';
// Load env file
dotenv.config({ path: '../api/.development.env' });
DataSource definition
const AppDataSource = new DataSource({
type: 'postgres',
url: process.env.DATABASE_URL,
logging: true,
entities: ['../api/dist/**/*.entity.js'],
migrations: ['./migrations/*.js'],
subscribers: [],
});
export default AppDataSource;
This way, you can store in your environment your database connection settings.

Answer 3

You could hide ormconfig.json and put your secrets directly in there, or viceversa, load TypeORM's configuration from your .env file. Is there a precise reason why you need them to be separated? If yes, then we can work out a solution.