TypeORM: Generate migrations without dedicated ormconfig file

Question

Of the several ways of connecting to a database offered by TypeORM (json, env, yml...) I choose to set my Connection Options programatically within my project's code using a regular TypeScript file as follows:

// src/database/createConnection.ts

import { createConnection } from 'typeorm';

    const connectionOptions = {
        type: 'postgres',
        host: POSTGRES_HOST_PROD,
        port: Number(POSTGRES_PORT),
        username: POSTGRES_USER,
        password: POSTGRES_PASSWORD,
        database: POSTGRES_DB,
        entities: ['build/entities/**/typeDef.js'],
        migrations: ['build/database/migrations/*.js'],
        cli: {
            migrationsDir: 'src/database/migrations/'
        }
    };

await createConnection(connectionOptions);

With the values fed by a regular .env file.

My problem is that when trying to create migration files through npx typeorm migration:generate -n initial I get an error as the command expects a specific orm configuration file to be present (ormconfig.env, ormconfig.json, etc).

As I already have my connection options set, this is not only redundant, it would also be processed instead of the configuration I have already set in the .ts file, and the only solution I see would be to rename the variables in my (non-typeorm-specific) .env file to match the specific TypeORM variable names, which I'd prefer not to do.

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TL:DR Is there a way of generating TypeORM migrations without creating a dedicated orm config file?

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Answer 1

Oh, turns out TypeORM already has a built-in option for this which does not require an extra ormconfig file, one can just add the property migrationsRun: true to the Connection Options (making sure synchronize is set to false).

For instance:

import { createConnection } from 'typeorm';

const connectionOptions = {
    type: 'postgres',
    host: POSTGRES_HOST_PROD,
    port: Number(POSTGRES_PORT),
    username: POSTGRES_USER,
    password: POSTGRES_PASSWORD,
    database: POSTGRES_DB,
    migrationsRun: true,
    entities: ['build/entities/**/typeDef.js'],
    migrations: ['build/database/migrations/*.js'],
    cli: {
        migrationsDir: 'src/database/migrations/'
    }
};

await createConnection(connectionOptions);