In this tutorial, we will be discussing how to implement file upload in an Angular application using Firebase as the backend. We will be covering both single and multiple file uploads, as well as the ability to upload files via drag-and-drop or by selecting them through a file dialog.
We will be using the AngularFire2 library, which is the official library for Firebase in Angular, to handle the communication between the Angular application and Firebase.
How to Upload Files in Firebase Store Single or Multiple?
Step 1: Create a new Angular application
Step 2: Install the AngularFire2 library
Step 3: Configure Firebase in your Angular application
Step 4: Import the AngularFireModule and AngularFireStorageModule
Step 5: Create a file upload component
Step 6: Implement the file upload functionality
Step 7: Implement Multiple File Uploads
Prerequisites
Before we begin, make sure you have the following installed:
- Node.js
- Angular CLI
- Firebase account and project set up
- AngularFire2 library
Step 1: Create a new Angular application
To create a new Angular application, open the command prompt and run the following command:
ng new myAppThis will create a new Angular application with the name “myApp” in a new directory.
Step 2: Install the AngularFire2 library
To install the AngularFire2 library, open the command prompt and navigate to the root of your Angular application. Run the following command:
npm install firebase angularfire2 --saveThis will install the Firebase and AngularFire2 libraries in your application.
Step 3: Configure Firebase in your Angular application
To configure Firebase in your Angular application, open the “src/environments/environment.ts” file and add your Firebase configuration. The configuration can be obtained from the Firebase project settings page.
export const environment = {
production: false,
firebase: {
apiKey: '<your-api-key>',
authDomain: '<your-auth-domain>',
databaseURL: '<your-database-url>',
projectId: '<your-project-id>',
storageBucket: '<your-storage-bucket>',
messagingSenderId: '<your-sender-id>'
}
};
Step 4: Import the AngularFireModule and AngularFireStorageModule
In your “src/app/app.module.ts” file, import the AngularFireModule and AngularFireStorageModule and add them to the imports array.
import { AngularFireModule } from 'angularfire2';
import { AngularFireStorageModule } from 'angularfire2/storage';
import { environment } from '../environments/environment';
@NgModule({
imports: [
AngularFireModule.initializeApp(environment.firebase),
AngularFireStorageModule
],
...
})
export class AppModule { }
Step 5: Create a file upload component
To create a file upload component, open the command prompt and navigate to the root of your Angular application. Run the following command:
ng g component file-uploadThis will create a new file upload component in the “src/app” directory.
Step 6: Implement the file upload functionality
In the “src/app/file-upload/file-upload.component.ts” file, import the AngularFireStorage service and create a method for handling file uploads.
import { AngularFireStorage } from 'angularfire2/storage';
export class FileUploadComponent {
constructor(private storage: AngularFireStorage) { }
upload(event) {
const file = event.target.files[0];
const filePath = 'path/to/save/file';
const fileRef = this.storage.ref(filePath);
const task = fileRef.put(file);
// subscribe to the task to handle success or failure
}
}In the “src/app/file-upload/file-upload.component.html” file, you can create a file input element and a drop area for drag-and-drop file uploads, and bind them to the upload method.
<div>
<input type="file" (change)="upload($event)">
</div>
<div class="drop-area" (drop)="upload($event)" (dragover)="$event.preventDefault()">
<p>Drag and drop file here</p>
</div>You can also add some styles to the drop area to indicate when a file is being dragged over it.
.drop-area {
height: 200px;
border: 1px solid #ccc;
display: flex;
align-items: center;
justify-content: center;
}
.drop-area.drag-over {
background-color: #eee;
}In your component.ts file, you can add a variable to track whether a file is being dragged over the drop area, and toggle its value on the dragover and drop events.
export class FileUploadComponent {
isDragging = false;
constructor(private storage: AngularFireStorage) { }
upload(event) {
// file upload logic here
}
onDragOver() {
this.isDragging = true;
}
onDrop() {
this.isDragging = false;
}
}In your template, you can use this variable to add the “drag-over” class to the drop area when a file is being dragged over it.
<div class="drop-area" (drop)="upload($event); onDrop()" (dragover)="$event.preventDefault(); onDragOver()" [class.drag-over]="isDragging">
<p>Drag and drop file here</p>
</div>
Step 7: Implement Multiple File Uploads
To implement multiple file uploads, you can modify the file input element to allow multiple files to be selected, and modify the upload method to handle an array of files.
In the “src/app/file-upload/file-upload.component.html” file, you can add the “multiple” attribute to the file input element
<div>
<input type="file" (change)="upload($event)" multiple>
</div>In the “src/app/file-upload/file-upload.component.ts” file, you can modify the upload method to handle an array of files and upload each file individually.
upload(event) {
const files = event.target.files;
for (const file of files) {
const filePath = 'path/to/save/file';
const fileRef = this.storage.ref(filePath);
const task = fileRef.put(file);
// subscribe to the task to handle success or failure
}
}
Step 8: Handle Success and Failure
You can handle the success and failure of the file upload by subscribing to the task object returned by the put method. In the subscribe method, you can check the task’s snapshot to see if the upload is complete, and if so, you can get the download URL of the file.
task.snapshotChanges().subscribe(snapshot => {
if (snapshot.bytesTransferred === snapshot.totalBytes) {
fileRef.getDownloadURL().subscribe(url => {
console.log(url);
// use the download URL for further actions
});
}
});
Continue : Firebase – View Images in List/ Tile/ Fullscreen in Angular
Conclusion
In this tutorial, we have discussed how to implement file upload in an Angular application using Firebase as the backend. We have covered both single and multiple file uploads, as well as the ability to upload files via drag-and-drop or by selecting them through a file dialog. We have also discussed how to handle success and failure of file uploads using the AngularFire2 library and Firebase Storage. This feature can be useful for many applications and will improve the user experience with more functionality.
