NestJS typed configuration with full TypeScript support.
Install additional peer dependencies:
- Create enum with names for all the required environment variable names, interface with type for every environment variable and validation schema using joi.
export enum EnvironmentVariablesEnum {
POSTGRES_USERNAME = 'POSTGRES_USERNAME',
POSTGRES_PASSWORD = 'POSTGRES_PASSWORD',
POSTGRES_HOST = 'POSTGRES_HOST',
}
export interface EnvironmentVariablesInterface {
[EnvironmentVariablesEnum.POSTGRES_USERNAME]: string;
[EnvironmentVariablesEnum.POSTGRES_PASSWORD]: string;
[EnvironmentVariablesEnum.POSTGRES_HOST]: string;
}
import Joi from 'joi';
export const environmentVariablesValidationSchema = Joi.object({
[EnvironmentVariablesEnum.POSTGRES_USERNAME]: Joi.string().required(),
[EnvironmentVariablesEnum.POSTGRES_PASSWORD]: Joi.string().required(),
[EnvironmentVariablesEnum.POSTGRES_HOST]: Joi.string().required(),
});- Create config module and service for NestJS DI, this module and service should be used in the project:
import { Inject, Injectable } from '@nestjs/common';
import { NestJSTypedConfigModule } from '@rnw-community/nestjs-typed-config';
const [BaseConfigModule, BaseConfigService] = NestJSTypedConfigModule.create<
EnvironmentVariablesEnum,
EnvironmentVariablesInterface
>(environmentVariablesValidationSchema);
@Injectable()
export class ConfigService extends BaseConfigService {}
@Module({
imports: [BaseConfigModule],
providers: [ConfigService],
exports: [ConfigService],
})
export class ConfigModule {}import { ConfigService } from './config.module.ts';
@Injectable()
class DomainService {
private readonly postgresPassword: string;
constructor(private readonly config: ConfigService) {
this.postgresPassword = config.get(EnvironmentVariablesEnum.POSTGRES_PASSWORD);
}
// ...
}To read an environment variable from file, the environment variable name should end with _FILE:
export enum EnvironmentVariablesEnum {
POSTGRES_PASSWORD_FILE = 'POSTGRES_PASSWORD_FILE',
}Value of that environment variable should be a path to the file:
echo $POSTGRES_PASSWORD_FILE
/secrets/postgres_pwdThis library is licensed under The MIT License.