Configuration

The configuration files of your AdonisJS application are stored inside the config directory. A brand new AdonisJS application comes with a handful of pre-existing files used by the framework core and installed packages.

Feel free to create additional files your application requires inside the config directory.

Importing config files

You may import the configuration files within your application codebase using the standard JavaScript import statement. For example:

import { appKey } from '#config/app'

import databaseConfig from '#config/database'

Using the config service

The config service offers an alternate API for reading the configuration values. In the following example, we use the config service to read the appKey value stored within the config/app.ts file.

import config from '@adonisjs/core/services/config'

config.get('app.appKey')
config.get('app.http.cookie') // read nested values

The config.get method accepts a dot-separated key and parses it as follows.

• The first part is the filename from which you want to read the values. I.e., app.ts file.
• The rest of the string fragment is the key you want to access from the exported values. I.e., appKey in this case.

Config service vs. directly importing config files

Using the config service over directly importing the config files has no direct benefits. However, the config service is the only choice to read the configuration in external packages and edge templates.

Reading config inside external packages

If you are creating a third-party package, you should not directly import the config files from the user application because it will make your package tightly coupled with the folder structure of the host application.

Instead, you should use the config service to access the config values inside a service provider. For example:

import { ApplicationService } from '@adonisjs/core/types'

export default class DriveServiceProvider {
  constructor(protected app: ApplicationService) {}
  
  register() {
    this.app.container.singleton('drive', () => {
      const driveConfig = this.app.config.get('drive')
      return new DriveManager(driveConfig)
    })
  }
}

Reading config inside Edge templates

You may access configuration values inside edge templates using the config global method.

<a href="{{ config('app.appUrl') }}"> Home </a>

You can use the config.has method to check if a configuration value exists for a given key. The method returns false if the value is undefined.

@if(config.has('app.appUrl'))
  <a href="{{ config('app.appUrl') }}"> Home </a>
@else
  <a href="/"> Home </a>
@end

Changing the config location

You can update the location for the config directory by modifying the adonisrc.ts file. After the change, the config files will be imported from the new location.

directories: {
  config: './configurations'
}

Make sure to update the import alias within the package.json file.

{
  "imports": {
    "#config/*": "./configurations/*.js"
  }
}

Config files limitations

The config files stored within the config directory are imported during the boot phase of the application. As a result, the config files cannot rely on the application code.

For example, if you try to import and use the router service inside the config/app.ts file, the application will fail to start. This is because the router service is not configured until the app is in a booted state.

Fundamentally, this limitation positively impacts your codebase because the application code should rely on the config, not vice versa.

Updating config at runtime

You can mutate the config values at runtime using the config service. The config.set updates the value within the memory, and no changes are made to the files on the disk.

import env from '#start/env'
import config from '@adonisjs/core/services/config'

const HOST = env.get('HOST')
const PORT = env.get('PORT')

config.set('app.appUrl', `http://${HOST}:${PORT}`)