vue-transmit

Vue-Transmit

A Vue.js drag & drop uploader based on Dropzone.js (~22KB, ~6.5KB gzipped). Many thanks to Matias Meno for paving the way with the original Dropzone.js! Check it out for any of your non-vue projects. 🙌

Features

Vue-Transmit is a fork of Dropzone.js that has been completely rewritten in TypeScript/ES6 for Vue.js. Instead of creating a Vue wrapper component that duplicates and proxies all of the methods and event logic between Dropzone and the component, Vue-Transmit implements them directly from the component. This cuts down on library size and offers a much tighter integration.

Vue-Transmit takes an event-based approach to the upload cycle. Instead of passing callbacks to the component via an options object, use the template event binding syntax (<vue-transmit @event="callback" />). All events strictly conform to kebab-casing, including events proxied off native events (e.g. dragover => @drag-over). This is for uniformity and so events can be easily distinguished.

Vue-Transmit also has a modular upload transport. The default transport implementation uses XMLHttpRequest to upload client-side files using multi-part form data, but this could be swapped for a custom implementation for something like Firebase.

In order to integrate with Vue.js reactivity, an object's properties must be defined initially, be enumerable, and be configurable. A special File class has been written (VTransmitFile) to register native browser file objects from uploads reactively, since the native object properties are read-only. This class also adds useful information not present in the native File object (dimensions, upload stats, etc.).

• HTML 5 file uploads
• Emits upload lifecycle events (accepted, sending, progress, success, etc.)
• Image thumbnail previews
• Support for concurrent uploads
• Modular upload transport layer
• Completely written in Vue.js—no wrapper components
• Scoped slots allow for fully customizable styling
• Written in modern TypeScript/ES6 with modules

* Note: this library uses some built-ins (Array.from, Promise) that require a polyfill. All other ESNext language features (arrow fns, for of, etc.) are transpiled with TypeScript.

Installation

npm install vue-transmit

Builds

The default build for ESM loaders like webpack is indicated in the module field of the package, while non-esm will resolve from the main field. By default, the unminified versions are specified. For most setups, importing the lib would like either of the following:

// ESM
import VueTransmit from "vue-transmit";
// Common.js
const VueTransmit = require("vue-transmit");
// Browser
window.VueTransmit;

// Installation
Vue.use(VueTransmit);

Target	Path	Minified
ESM	vue-transmit/dist/vue-transmit.esm.js	false
ESM	vue-transmit/dist/vue-transmit.esm.min.js	true
UMD	vue-transmit/dist/vue-transmit.js	false
UMD	vue-transmit/dist/vue-transmit.min.js	true

Props: <vue-transmit>

Property	Type	Default
tag	String	"div"
uploadAreaClasses	Array, Object, String	null
uploadAreaAttrs	Object	{}
uploadAreaListeners	Object	{}
url	String	undefined
method	String	"post"
withCredentials	Boolean	false
timeout	Number	0
maxConcurrentUploads	Number	2
uploadMultiple	Boolean	false
maxFileSize	Number	256 (in MiB)
paramName	String	"file"
createImageThumbnails	Boolean	true
maxThumbnailFileSize	Number	10
thumbnailWidth	Number	120
thumbnailHeight	Number	120
fileSizeBase	Number	1000
maxFiles	Number	null
params	Object	default
headers	Object	default
responseType	String	""
clickable	Boolean	true
ignoreHiddenFiles	Boolean	true
acceptedFileTypes	Array	default
autoProcessQueue	Boolean	true
autoQueue	Boolean	true
capture	String	null
renameFile	Function	identity
dictFileTooBig	String	"File is too big ({{ fileSize }}MiB). Max file size: {{ maxFileSize }}MiB."
dictInvalidFileType	String	"You can't upload files of this type."
dictResponseError	String	"Server responded with {{ statusCode }} code."
dictMaxFilesExceeded	String	"You can not upload any more files."
accept	Function	default
resize	Function	default

Events

Event	Arguments	Description
drop	DragEvent	The drop event is fired when an data transfer is dropped on the drop target.
drag-start	DragEvent	The drag-start event is fired when the user starts dragging an element or text selection.
drag-end	DragEvent	The drag-end event is fired when a drag operation is being ended (by releasing a mouse button or hitting the escape key).
drag-enter	DragEvent	The drag-enter event is fired when a dragged element or text selection enters a valid drop target.
drag-over	DragEvent	The drag-over event is fired when an element or text selection is being dragged over a valid drop target (every few hundred milliseconds).
drag-leave	DragEvent	The drag-leave event is fired when a dragged element or text selection leaves a valid drop target.
added-file	VTransmitFile	Fired on change from the hidden file input after the Native File has been copied to VTransmitFile and added to the component data. (status: 'added')
added-files	VTransmitFile[]	Fired on change from the hidden file input after the Native Files have been copied to VTransmitFiles and added to the component data. (status: 'added')
accepted-file	VTransmitFile	Fired if the user-supplied accept function returns without error. (status: 'added', accepted: true)
rejected-file	VTransmitFile	Fired if the user-supplied accept function returns an error. Fired AFTER the error event to ensure correct file status. (status: 'error', accepted: false)
accept-complete	VTransmitFile	Fired after the user-supplied accept function has returned regardless of success/failure. Fired after accepted-file & rejected-file. (status: ?, accepted: ?)
removed-file	VTransmitFile	Fired on the removal of a file.
thumbnail	VTransmitFile, Blob|URL	Fires on creation of a thumbnail.
error	VTransmitFile, message: String, XmlHttpRequest	Fired on an ajax upload error. (status: 'error')
error-multiple	VTransmitFile[], message: String, XmlHttpRequest	Fired on an ajax upload error. (status: 'error')
processing	VTransmitFile	Fired after the status is changed to 'uploading', right before the ajax request.
processing-multiple	VTransmitFile[]	Fired after the status is changed to 'uploading', right before the ajax request.
upload-progress	VTransmitFile, progress: Number, bytesSent: Number	Fired on progress of the XHR.
total-upload-progress	VTransmitFile, totalUploadProgress: Number	Fired directly after upload-progress.
sending	VTransmitFile, XmlHttpRequest, FormData	Fired right before the XHR is sent.
sending-multiple	VTransmitFile[], XmlHttpRequest, FormData	Fired right before the XHR is sent.
success	VTransmitFile, response: String, ProgressEvent	Fired on load of the XHR.
success-multiple	VTransmitFile[], response: String, ProgressEvent	Fired on load of the XHR.
timeout	VTransmitFile, TimeoutEvent, XmlHttpRequest	Fired on timeout of the XHR.
timeout-multiple	VTransmitFile[], TimeoutEvent, XmlHttpRequest	Fired on timeout of the XHR.
canceled	VTransmitFile	Fired upon cancellation of the XHR. (status: 'canceled')
canceled-multiple	VTransmitFile[]	Fired upon cancellation of the XHR. (status: 'canceled')
complete	VTransmitFile	Fired upon completion of the XHR. (success or failure)
complete-multiple	VTransmitFile[]	Fired upon completion of the XHR. (success or failure)
reset	n/a	Fired when all files have been removed.
max-files-exceeded	VTransmitFile	Fired if a file is added that exceeds the max files prop.
max-files-reached	VTransmitFile[]	Fired when the total accepted files on the instance exceeds the max files prop.
queue-complete	VTransmitFile	Fired once all added files have uploaded and the queue has been flushed.

Slots

Default ($slots.default)

The default slot should contain your markup for getting an upload started. This could be a file uploader button and/or a dropzone.

Files (Scoped, $slots.files)

This slot receives a number of props:

interface FilesSlotProps {
  files: VTransmitFile[];
  acceptedFiles: VTransmitFile[];
  rejectedFiles: VTransmitFile[];
  addedFiles: VTransmitFile[];
  queuedFiles: VTransmitFile[];
  uploadingFiles: VTransmitFile[];
  activeFiles: VTransmitFile[];
  isUploading: Boolean;
}

VTransmitFile

{
  "_nativeFile": {},
  "id": "v-transmit-file-1",
  "accepted": true,
  "lastModified": 1478117443000,
  "lastModifiedDate": "2016-11-02T20:10:43.000Z",
  "name": "cosmo.jpg",
  "processing": true,
  "size": 142776,
  "status": "success",
  "type": "image/jpeg",
  "upload": {
    "bytesSent": 142776,
    "progress": 100,
    "speed": {
      "kbps": 10.06,
      "mbps": 0.01
    },
    "start": 1503273157993,
    "end": 1503273158029,
    "time": 0.036,
    "total": 142776
  },
  "webkitRelativePath": "",
  "width": 700,
  "height": 700,
  "xhr": {},
  "dataUrl":
    "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAHgAAAB4CAYAAAA5ZDbSAAAgAElEQVR4XlS9B7RmZ3UluG/="
}

Usage

If you have PHP installed on your machine, you can clone this repo and open up a working test app by running:

npm test

Now navigate to http://localhost:3030/.

<template>
  <main id="root" class="mt-5">
    <div class="container">
      <div class="row">
        <header class="col-12 text-center">
          <h1 class="mb-5"><code>&lt;vue-transmit&gt;</code></h1>
        </header>
        <vue-transmit class="col-12"
                      tag="section"
                      v-bind="options"
                      upload-area-classes="bg-faded"
                      ref="uploader">
          <div class="d-flex align-items-center justify-content-center w-100"
                style="height:50vh; border-radius: 1rem;">
            <button class="btn btn-primary"
                    @click="triggerBrowse">Upload Files</button>
          </div>
          <!-- Scoped slot -->
          <template slot="files" slot-scope="props">
            <div v-for="(file, i) in props.files" :key="file.id" :class="{'mt-5': i === 0}">
              <div class="media">
                <img :src="file.dataUrl" class="img-fluid d-flex mr-3">
                <div class="media-body">
                  <h3>{{ file.name }}</h3>
                  <div class="progress" style="width: 50vw;">
                    <div class="progress-bar bg-success"
                        :style="{width: file.upload.progress + '%'}"></div>
                  </div>
                  <pre>{{ file | json }} </pre>
                </div>
              </div>
            </div>
          </template>
        </vue-transmit>
      </div>
    </div>
  </main>
</template>

<script>
  Vue.use(VueTransmit)
  window.app = new Vue({
    el: '#root',
    data: {
      options: {
        acceptedFileTypes: ['image/*'],
        clickable: false,
        adapterOptions: {
          url: './upload.php',
        },
      }
    },
    methods: {
      triggerBrowse() {
        this.$refs.uploader.triggerBrowseFiles()
      },
    },
    filters: {
      json(value) {
        return JSON.stringify(value, null, 2)
      }
    }
  })
</script>

Lifecycle

The upload process has many stages, each with different possible outcomes. Here is an overview of the lifecycle of an upload with Vue Transmit:

• Trigger event
  • input on change: value of input.files is read and passed to vm.addFile
  • target on drop: value of event.dataTransfer["files" || "items"] is read/traversed and passed to vm.addFile
• Add File
  • instantiate VTransmitFile from native file object (for reactivity & extra info)
  • status added
  • pushed onto vm.files
  • thumbnail is enqueued
• Accept File
  • check size, type, upload limit
  • invoke accept function for consumer validation
  • accept or reject complete
  • if autoQueue, enqueue file
• Enqueue file
  • check that file status is added & has been accepted
  • status = queued
  • if autoProcessQueue, invoke processQueue async (like node setImmediate)
• Process queue
  • check number of uploading files against upload limit
  • invoke processFiles with max amount of queued files options allow
• Process files
  • do upload
• Progress updates
• Complete upload
  • status = success || error
  • process queue to handle buffered files

Changelog

9.0.0-alpha.2 (2018-02-09)

Features

• abstract upload transport into adapter (#27) (6cf71cf)

<a name="9.0.0-alpha.1"></a>