Flagsmith - Setup - Feature Flagging Solution

Flagsmith makes it easy to create and manage features flags across web, mobile, and server side applications. Just wrap a section of code with a flag, and then use Flagsmith to toggle that feature on or off for different Environments, Users or user Segments 

 

*For Windows 11 with WSL enabled.

Install Docker

Download link 

Keep in mind to enable WSL when installing Docker

Setup Flagsmith Server

git clone https://github.com/Flagsmith/flagsmith

cd flagsmith

docker compose up -d

Open Flagsmith UI Console in the browser to log in for the first time: http://localhost:8000/singup

 

Install NodeJS

sudo apt install curl

curl https://raw.githubusercontent.com/creationix/nvm/master/install.sh | bash 

source ~/.bashrc

nvm ls-remote

nvm install 18.18.2 (put the version you need)

npm install flagsmith

npm install xhr2

Set your environmentID

 

Find your apikey

 

Create NodeJS small app index.js

const flagsmith = require("flagsmith"); //Add this line if you're using flagsmith via npm

global.XMLHttpRequest = require('xhr2');

//const featureFlagAPI = "https://api.flagsmith.com/api/v1/flags/";

const featureFlagAPI = "http://localhost:8000/api/v1/flags/";

const apiKey = "*******************************";

function print_state(){

if (flagsmith.default.hasFeature("awesome")) {

console.log('awesome feature is enabled')

}

else

console.log('awesome - is disabled')

}

// Start function

const start = async function() {

console.log('Calling init ...')

await flagsmith.default.init({

environmentID:"*****************",

api:"http://localhost:8000/api/v1/"

});

;

await updateFeatureFlag('awesome', false);

flagsmith.default.startListening(1000)

while (true) {

await new Promise(resolve => setTimeout(resolve, 1000));

print_state()

}

}

async function updateFeatureFlag(flagId, isEnabled) {

try {

console.log('Updated has started')

const response = await fetch(`${featureFlagAPI}${flagId}/`, {

method: 'PATCH',

headers: {

'Content-Type': 'application/json',

'Authorization': `Bearer ${apiKey}`

},

body: JSON.stringify({

enabled: isEnabled

})

});

const data = await response.text();

console.log(data);

} catch (error) {

console.error('An error occurred:', error);

}

}

// Usage

start()

 

Testing Feature Flagging

start your app:

 

node index.js 

  you'll in the terminal running:

awesome - is disabled
awesome - is disabled
awesome - is disabled
awesome - is disabled

 

 

 

 Go to Flagsmith UI Console and enable you awesome flag

   you'll see that in the terminal it will change the message to:

awesome feature is enabled
awesome feature is enabled
awesome feature is enabled
awesome feature is enabled