NestJS-Env-Config

Getting Started

$3

``console
npm install nestjs-env-config --save
`

$3

It's easy to use NestJSConfig APIs to parse, validate and load environment config in NestJS.

The config is divided 3 sections.

* Config: The config object that you will find in your NestJS API.
* DTO: A class validator DTO to validate config.
* Default: Defines all default values here.

config.ts
`typescript
export interface APIConfig extends BaseConfig {
database: DatabaseConfig;
ssl: SSLConfig;
jwt: JWTConfig;
}

export interface JWTConfig {
secret: string;
expiresIn: string;
}

export interface SSLConfig {
enabled: boolean;
keyPath: string;
certPath: string;
}

export interface DatabaseConfig {
host: string;
port: number | null;
username: string | null;
password: string | null;
name: string | null;
}

export const getConfig = (env: Record): APIConfig => {
const config = validateConfig(ConfigEnvironmentDto, defaultConfig, env);

return {
port: config.AP_APP_PORT,
currentEnv: config.AP_APP_ENV,
verbose: config.AP_APP_VERBOSE,
whitelistedOrigins: config.AP_APP_URLS_WHITELIST,
frontendUrl: config.AP_APP_FRONTEND_URL,
database: {
host: config.AP_DB_HOST,
port: config.AP_DB_PORT,
name: config.AP_DB_NAME,
username: config.AP_DB_USER,
password: config.AP_DB_PASSWORD,
},
ssl: {
enabled: config.AP_SSL_ENABLED,
keyPath: config.AP_SSL_KEY_PATH,
certPath: config.AP_SSL_CERT_PATH,
},
jwt: {
secret: config.AP_JWT_SECRET,
expiresIn: config.AP_JWT_EXPIRE_IN,
},
};
};
`

config.environment.dto.ts

`typescript
const UseDefault = () => BaseUseDefault(defaultConfig);

export class ConfigEnvironmentDto {
//Base config
@ConfigValidators(isPortNumber)
@Expose()
@UseDefault()
@UseEnvPort()
@TransformNumber()
@Desc('Port to listen on')
AP_APP_PORT: number;

@ConfigValidator(isEnum, Environment)
@Expose()
@UseDefault()
@Desc('Environment to run in')
AP_APP_ENV: Environment;

@ConfigValidators(isBoolean)
@Expose()
@UseDefault()
@TransformBoolean()
@Desc('Enable debug mode')
AP_APP_VERBOSE: boolean;

@ConfigValidators(isUrlArray)
@Expose()
@TransformArray()
@UseDefault()
@Desc('List of urls to proxy')
AP_APP_URLS_WHITELIST: string[];

@ConfigValidators(isString)
@Expose()
@UseDefault()
@Desc('Path of the frontend')
AP_APP_FRONTEND_URL: string;

// Database
@ConfigValidators(isString)
@Expose()
@UseDefault()
@Desc('Database host')
@Secret()
AP_DB_HOST: string;

@Expose()
@UseDefault()
@Desc('Database name')
AP_DB_NAME: string | null;

@Expose()
@UseDefault()
@Desc('Database user')
@Secret()
AP_DB_USER: string | null;

@Expose()
@UseDefault()
@Desc('Database password')
@Secret()
AP_DB_PASSWORD: string | null;

@Expose()
@UseDefault()
@TransformNumber()
@Desc('Database port')
AP_DB_PORT: number | null;

// SSL
@ConfigValidators(isBoolean)
@Expose()
@TransformBoolean()
@UseDefault()
@Desc('Is database ssl enabled')
AP_SSL_ENABLED: boolean;

@ConfigValidators(isString)
@Expose()
@UseDefault()
@Desc('Database ssl key path')
AP_SSL_KEY_PATH: string;

@ConfigValidators(isString)
@Expose()
@UseDefault()
@Desc('Database ssl cert path')
AP_SSL_CERT_PATH: string;

// JWT
@ConfigValidators(isString)
@Expose()
@UseDefault()
@Desc('JWT secret')
@Secret()
AP_JWT_SECRET: string;

@ConfigValidators(isValidPeriod, isString)
@Expose()
@UseDefault()
@Desc('JWT expiration time')
AP_JWT_EXPIRE_IN: string;
}
`

config.default
`typescript
export enum Environment {
DEV = 'dev',
STAGING = 'staging',
PROD = 'prod',
TEST = 'test',
}

export const defaultConfig: ConfigEnvironmentDto = {
AP_APP_PORT: 3000,
AP_APP_ENV: Environment.DEV,
AP_APP_VERBOSE: false,
AP_APP_URLS_WHITELIST: ['http://localhost:4200'],
AP_APP_FRONTEND_URL: 'http://localhost:4200',

// Database
AP_DB_HOST: 'localhost',
AP_DB_NAME: null,
AP_DB_USER: null,
AP_DB_PASSWORD: null,
AP_DB_PORT: null,

// SSL
AP_SSL_ENABLED: false,
AP_SSL_KEY_PATH: '/ssl/cert.key',
AP_SSL_CERT_PATH: '/ssl/cert.crt',

// JWT
AP_JWT_SECRET: 'myverysecretkey',
AP_JWT_EXPIRE_IN: '1-day',
};
`

Use it in your application getConfig()
In my case I used it in a custom function, but you can use it directly in the config service loader.

`typescript
const loadAPIConfig = async (): Promise<{
config: APIConfig;
sslOptions: NestApplicationOptions;
}> => {
const config = getConfig(process.env);
return { config, sslOptions: await getSSLOptions(config.ssl) };
};
``

License

NestJSConfig is licensed under a MIT License.