This article shows how you can set up different configuration files for different servers like a production server or development server.
For example, we can have different database configuration settings for development server and production server. If we write the database config settings (hostname, username, password) in the single file then we have to manually change them in development and production server separately.
To make this more systematic, there can be different solutions. Here, I will discuss two Node.js modules that can be used to store the configuration settings. Hence, easing up the app deployment process.
I have created a folder named “nodejs” inside my Documents folder. And, then created a simple Node.js app over there.
mukesh:nodejs chapagain$ pwd
/Users/mukeshchapagain/Documents/nodejs
Using dotenv module
Dotenv is a Node.js module that loads environment variables from a .env file into process.env.
Using this module, you can have different content in the .env file present in your development and production server.
We will install the dotenv module to access the .env file contents.
npm install dotenv --save
My application files,
– the main application file is
app.js
– the environment variables are stored in.envfile
Note:
Remember to ignore the .env file in your git repository by creating a .gitignore file and adding the .env line over there. Otherwise, your private information stored in the .env file might get exposed.
dotenv module is used to include the .env file in our main app js file.
.env
DB_HOST=localhost
DB_USER=yourDbUsername
DB_PASS=yourDbPassword
app.js
require('dotenv').config(); // include .env file
let db = {
host: process.env.DB_HOST,
username: process.env.DB_USER,
password: process.env.DB_PASS
};
console.log(db);
Run the application:
node app.js
Output
mukesh:nodejs chapagain$ node app.js
{ host: 'localhost',
username: 'yourDbUsername',
password: 'yourDbPassword' }
Using config module
Config is a Node.js module that lets you define a set of default parameters in a configuration file. That configuration file can then be extended for different deployment environments (development, qa, staging, production, etc.).
Install the config module
npm install config --save
Create a config folder
mkdir config
Create default.json file inside the config folder
touch config/default.json
Add the following code to config/default.json file
config/default.json
{
"Settings": {
"dbConfig": {
"host": "localhost",
"port": 5984,
"dbName": "yourDatabaseName"
},
"site": {
"url": "http://localhost.com",
"myVar": 10
}
}
}
In the above code, we can also set the values in environment variables and use them in the above JSON file.
config/default.json
{
"Settings": {
"dbConfig": {
"host": process.env.DB_HOST || "localhost",
"port": parseInt(process.env.APP_PORT) || 5984,
"dbName": process.env.DB_NAME || "yourDatabaseName"
},
"site": {
"url": process.env.SITE_URL || "http://localhost.com",
"myVar": 10
}
}
}
app.js
var config = require('config');
var settings = config.get('Settings');
var dbConfig = config.get('Settings.dbConfig');
var site = config.get('Settings.site');
var siteUrl = config.get('Settings.site.url');
console.log('\n SETTINGS \n');
console.log(settings);
console.log('\n DBCONFIG \n');
console.log(dbConfig);
console.log('\n SITE \n');
console.log(site);
console.log('\n SITEURL \n');
console.log(siteUrl);
Run the application:
node app.js
Output
mukesh:nodejs chapagain$ node app.js
WARNING: NODE_ENV value of 'default' is ambiguous.
WARNING: See https://github.com/lorenwest/node-config/wiki/Strict-Mode
SETTINGS
{ dbConfig: { host: 'localhost', port: 5984, dbName: 'yourDatabaseName' },
site: { url: 'http://localhost.com', myVar: 10 } }
DBCONFIG
{ host: 'localhost', port: 5984, dbName: 'yourDatabaseName' }
SITE
{ url: 'http://localhost.com', myVar: 10 }
SITEURL
http://localhost.com
DIFFERENT CONFIGURATION FOR PRODUCTION SERVER
The above code fetches the configuration settings from the config/default.json file. You can have different configuration settings for the production server.
In that case, you need to create a new file named “production.json” inside the “config” folder.
- The production.json file can override the default.json.
- So, you need not have to write everything there.
- You can just write the things that are different in production than the default one.
Create production.json file inside the config folder
touch config/production.json
Add the following code to config/production.json file
Here, we are only overriding the dbName and site URL of the default.json file.
config/production.json
{
"Settings": {
"dbConfig": {
"dbName": "productionDb"
},
"site": {
"url": "http://example.com"
}
}
}
JSON file with the environment variables.
config/production.json
{
"Settings": {
"dbConfig": {
"dbName": process.env.DB_NAME || "productionDb"
},
"site": {
"url": process.env.SITE_URL || "http://example.com"
}
}
}
app.js
app.js file will be the same.
var config = require('config');
var settings = config.get('Settings');
var dbConfig = config.get('Settings.dbConfig');
var site = config.get('Settings.site');
var siteUrl = config.get('Settings.site.url');
console.log('\n SETTINGS \n');
console.log(settings);
console.log('\n DBCONFIG \n');
console.log(dbConfig);
console.log('\n SITE \n');
console.log(site);
console.log('\n SITEURL \n');
console.log(siteUrl);
Set environment variable NODE_ENV as production.
export NODE_ENV=production
Run the application
node app.js
Output
mukesh:nodejs chapagain$ node app.js
SETTINGS
{ dbConfig: { host: 'localhost', port: 5984, dbName: 'productionDb' },
site: { url: 'http://example.com', myVar: 10 } }
DBCONFIG
{ host: 'localhost', port: 5984, dbName: 'productionDb' }
SITE
{ url: 'http://example.com', myVar: 10 }
SITEURL
http://example.com
In the output, you can see that the dbName has been changed in the dbConfig. Also, the Site url has changed. Those values are taken from config/production.json file. Rest of all the values are taken from config/default.json file.
You can also specify the environment variable NODE_ENV in your app.js file. If you define it in the app.js file then it will override the value you have set while exporting the environment variable.
process.env.NODE_ENV = “production”;
app.js
process.env.NODE_ENV = "production";
var config = require('config');
var settings = config.get('Settings');
var dbConfig = config.get('Settings.dbConfig');
var site = config.get('Settings.site');
var siteUrl = config.get('Settings.site.url');
console.log('\n SETTINGS \n');
console.log(settings);
console.log('\n DBCONFIG \n');
console.log(dbConfig);
console.log('\n SITE \n');
console.log(site);
console.log('\n SITEURL \n');
console.log(siteUrl);
Hope this helps. Thanks.