NgxFlow

The purpose of this package is to create a wrapper for Angular for fileupload using flow.js.

Demo

https://stackblitz.com/edit/ngx-flow-example

You can also find example source code in the src folder.

Roadmap

• ✅ upload single file
• ✅ upload multiple files
• ✅ queue management
• ✅ error handling
• ✅ pause / resume upload
• ✅ cancel upload, cancel all uploads
• ✅ upload progress
• ✅ file / directory restrictions
• ✅ drag & drop
• ✅ display uploaded image
• ✅ tests
• ✅ upload right after selecting file
• ✅ run tests using TravisCI
• ✅ demo using Stackblitz
• ✅ support for server side rendering

Install

npm install @flowjs/flow.js @flowjs/ngx-flow

Import in your module:

import { NgxFlowModule, FlowInjectionToken } from '@flowjs/ngx-flow';
import Flow from '@flowjs/flow.js';

@NgModule({
  imports: [NgxFlowModule],
  providers: [
    {
      provide: FlowInjectionToken,
      useValue: Flow
    }
  ]
})
export class AppModule

We use dependecy injection to provide flow.js library.

How to use

1. Start up server. There is a server example taken from flow.js here in server directory. In this repo you can run it using npm run server.

2. First you need to initialize ngx-flow directive and export it as for example flow variable:

   <ng-container #flow="flow" [flowConfig]="{target: 'http://localhost:3000/upload'}"></ng-container>

3. Now you can use either directive flowButton for select file dialog:

   <input type="file"
         flowButton
         [flow]="flow.flowJs"
         [flowAttributes]="{accept: 'image/*'}">

   Or flowDrop for drag&drop feature:

   <div class="drop-area"
       flowDrop
       [flow]="flow.flowJs">
   </div>

   For both you have to pass [flow]=flow.flowJs where flow is template variable exported in step 1.

4. You can than subscribe to observable of transfers:

   <div *ngFor="let transfer of (flow.transfers$ | async).transfers">

5. After adding files you can begin upload using upload() method:

   <button type="button" (click)="flow.upload()" [disabled]="!(flow.somethingToUpload$ | async)">Start upload</button>

How does transfers$ data look like?

Observable flow.transfers$ emits state in form:

{
  totalProgress: 0.5,
  transfers: [
    {
      name: "somefile.txt",
      flowFile: FlowFile,
      progress: number,
      error: boolean,
      paused: boolean,
      success: boolean,
      complete: boolean,
      currentSpeed: number,
      averageSpeed: number,
      size: number,
      timeRemaining: number,
    },
    {
      name: "uploading.txt",
      flowFile: FlowFile,
      progress: 0.5,
      error: false,
      paused: false,
      success: false,
      complete: false,
      currentSpeed: number,
      averageSpeed: number,
      size: number,
      timeRemaining: number,
    },
    {
      name: "failed-to-upload.txt",
      flowFile: FlowFile,
      progress: number,
      error: true,
      paused: false,
      success: false,
      complete: true,
      currentSpeed: number,
      averageSpeed: number,
      size: number,
      timeRemaining: number,
    }
    {
      name: "uploaded.txt",
      flowFile: FlowFile,
      progress: number,
      error: false,
      paused: false,
      success: true,
      complete: true,
      currentSpeed: number,
      averageSpeed: number,
      size: number,
      timeRemaining: number,
    }
  ],
  flow: { /* flow.js instance*/ }
}

FAQ

I need access to flow.js object

You can find it under flow variable.

<p>Is flowjs supported by the browser? {{flow.flowJs?.support}}</p>

I see flickering when upload is in progress

Use trackBy for ngFor:

<div *ngFor="let transfer of (flow.transfers$ | async).transfers; trackBy: trackTransfer">

export class AppComponent {
  trackTransfer(transfer: Transfer) {
    return transfer.id;
  }
}

I need just a single file

Add singleFile: true to your flow config:

<ng-container #flow="flow" [flowConfig]="{target: 'http://localhost:3000/upload', singleFile: true}"></ng-container>

I want to upload whole directory

Add flowDirectoryOnly="true" to your button:

<input type="file"
       flowButton
       [flow]="flow.flowJs"
       flowDirectoryOnly="true"
       [flowAttributes]="{accept: 'image/*'}">

I want to display image which is going to be uploaded

Use directive flowSrc:

<div *ngFor="let transfer of (flow.transfers$ | async).transfers">
  <img [flowSrc]="transfer">
</div>

How to trigger upload right after picking the file?

Subscribe to events$. NgxFlow listens for these events: filesSubmitted, fileRemoved, fileRetry, fileProgress, fileSuccess, fileError of flow.js. Event fileSubmitted is fired when user drops or selects a file.

export class AppComponent implements AfterViewInit, OnDestroy {
  @ViewChild('flow')
  flow: FlowDirective;

  autoUploadSubscription: Subscription;

  ngAfterViewInit() {
    this.autoUploadSubscription = this.flow.events$.subscribe(event => {
      if (event.type === 'filesSubmitted') {
        this.flow.upload();
      }
    });
  }

  ngOnDestroy() {
    this.autoUploadSubscription.unsubscribe();
  }
}

Development

npm run build - builds the library into dist folder

After that you can publish to npm repository from dist folder:

cd dist/ngx-flow
npm publish