@brightspace-ui-labs/file-uploader
v4.0.0
Published
Polymer-based web component for D2L file uploader
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@brightspace-ui-labs/file-uploader
Note: this is a "labs" component. While functional, these tasks are prerequisites to promotion to BrightspaceUI "official" status:
- [ ] Design organization buy-in
- [ ] design.d2l entry
- [ ] Architectural sign-off
- [x] Continuous integration
- [x] Cross-browser testing
- [x] Unit tests (if applicable)
- [ ] Accessibility tests
- [ ] Visual diff tests
- [ ] Localization with Serge (if applicable)
- [x] Demo page
- [x] README documentation
Polymer component for uploading files with drag and drop capability. This component does not perform the actual uploading work, it simply provides visual cues and exposes an event when files have been uploaded.
Installation
To install from NPM:
npm install @brightspace-ui-labs/file-uploader
Usage
<head>
<script type="module" src="@brightspace-ui-labs/file-uploader/d2l-file-uploader.js"></script>
</head>
Basic Usage with Accessible Label
It's important to always provide an accessible label which describes the purpose of the uploader using the label
attribute. The label will be hidden visually but associated with the upload input for those using assistive technologies such as a screen reader.
<d2l-labs-file-uploader label="profile picture"></d2l-labs-file-uploader>
Multi-file Uploads
To allow for multiple files to be uploaded, add the multiple
attribute:
<d2l-labs-file-uploader multiple ...></d2l-labs-file-uploader>
Localization
The file uploader will automatically render using the language found on the HTML element -- i.e. <html lang="fr">
. If the language attribute is not present or isn't supported, the uploader will render in English.
Feedback Messages
If you encounter a scenario where you'd like to display feedback about the uploaded file(s) -- like a warning or an error -- use the feedback
and feedback-type
attributes.
The feedback-type
defaults to "warning":
<d2l-labs-file-uploader
feedback="Sorry, we cannot upload files larger than 1GB.">
</d2l-labs-file-uploader>
But feedback-type
can also be set to "error":
<d2l-labs-file-uploader
feedback="An error occurred occurred processing the upload."
feedback-type="error"></d2l-labs-file-uploader>
Feedback Changed Event
To listen for when feedback changes within the uploader, register for the feedback-changed
event.
Vanilla JavaScript:
<d2l-labs-file-uploader id="my-uploader" ...></d2l-labs-file-uploader>
<script>
document.getElementById('my-uploader')
.addEventListener('feedback-changed', function(evt) {
var feedbackMessage = evt.detail.value;
console.log(feedbackMessage);
});
</script>
From within another Polymer element you can use Polymer's annotated event listeners:
<dom-module id="my-element">
<template>
<d2l-labs-file-uploader on-feedback-changed="handleFeedback"></d2l-labs-file-uploader>
</template>
</dom-module>
Handling Uploaded Files
When the user uploads one or more files, a d2l-file-uploader-files-added
event is fired. To listen for this event, wire up an event listener to the <d2l-labs-file-uploader>
element. The listener will be passed an event with an array of File objects from the File API.
Vanilla JavaScript:
<d2l-labs-file-uploader id="my-uploader" ...></d2l-labs-file-uploader>
<script>
document.getElementById('my-uploader')
.addEventListener('d2l-file-uploader-files-added', function(evt) {
var files = evt.detail.files;
console.log(files);
});
</script>
From within another Polymer element you can use Polymer's annotated event listeners:
<dom-module id="my-element">
<template>
<d2l-labs-file-uploader on-d2l-file-uploader-files-added="handleFileAdded"></d2l-labs-file-uploader>
</template>
</dom-module>
Developing, Testing and Contributing
After cloning the repo, run npm install
to install dependencies.
Linting
# eslint
npm run lint
Testing
# lint & run headless unit tests
npm test
# unit tests only
npm run test:headless
Running the demos
To start a @web/dev-server that hosts the demo page and tests:
npm start
Versioning and Releasing
This repo is configured to use semantic-release
. Commits prefixed with fix:
and feat:
will trigger patch and minor releases when merged to main
.
To learn how to create major releases and release from maintenance branches, refer to the semantic-release GitHub Action documentation.