Serverless Computing is setting it's way up for about 2 years now. Now we have Azure Functions, AWS Lambda and Google Cloud Functions.
This post is on simple steps to create Google Cloud Function setup.
Cloud functions is a serverless provided by Google Firebase. Developers can upload their back-end code in functions to the cloud and the cloud automatically executes the corresponding logic based on event triggers and HTTP requests.
For more details you can refer https://firebase.google.com/docs/functions/get-started
We will create two functions here as,
addMessage()
makeUppercase()
1. Install Node.js. Firebase CLI requires Node.js and npm.
2. Install the Firebase CLI using Node Command Prompt in admin mode.
"npm install -g firebase-tools"
3. Authenticate the firebase tool
Run "firebase login"
4. Go to https://console.firebase.google.com/ an create your project there. Go to your Firebase project directory.
Run "firebase init functions"
5. Select the firebase project or create a new one. Install dependencies with npm if needed.
6. Select the language.
After these commands complete successfully, your project structure looks like this:
myproject
+- .firebaserc # Hidden file that helps you quickly switch between
| # projects with `firebase use`
|
+- firebase.json # Describes properties for your project
|
+- functions/ # Directory containing all your functions code
|
+- .eslintrc.json # Optional file containing rules for JavaScript linting.
|
+- package.json # npm package file describing your Cloud Functions code
|
+- index.js # main source file for your Cloud Functions code
|
+- node_modules/ # directory where your dependencies (declared in # package.json) are installed
7. Open the index.js file and add your functions
For the addMessage() function, add these lines to index.js:
// Take the text parameter passed to this HTTP endpoint and insert it into the // Realtime Database under the path /messages/:pushId/original exports.addMessage = functions.https.onRequest((req, res) => { // Grab the text parameter. const original = req.query.text; // Push the new message into the Realtime Database using the Firebase Admin SDK. return admin.database().ref('/messages').push({original: original}).then((snapshot) => { // Redirect with 303 SEE OTHER to the URL of the pushed object in the Firebase console. return res.redirect(303, snapshot.ref.toString()); }); });For the makeUppercase() function, add these lines to index.js:
// Listens for new messages added to /messages/:pushId/original and creates an // uppercase version of the message to /messages/:pushId/uppercase exports.makeUppercase = functions.database.ref('/messages/{pushId}/original') .onCreate((snapshot, context) => { // Grab the current value of what was written to the Realtime Database. const original = snapshot.val(); console.log('Uppercasing', context.params.pushId, original); const uppercase = original.toUpperCase(); // You must return a Promise when performing asynchronous tasks inside a Functions such as // writing to the Firebase Realtime Database. // Setting an "uppercase" sibling in the Realtime Database returns a Promise. return snapshot.ref.parent.child('uppercase').set(uppercase); });
8. Run this command to deploy your functions:
"firebase deploy --only functions"
9. Now go and check your https://console.firebase.google.com/ project you will see the functions available there. Use the URL provided by CLI which will be available in firebase console function as well. It will be similar to below with your project name in it.
https://us-central1-MY_PROJECT.cloudfunctions.net/addMessage?text=uppercasemetoo
10. Now use this url in a browser and you will be navigated to firebase database where you can see the funtion results.
