Box Content Preview

The Box Content Preview library allows developers to easily embed high quality and interactive previews of Box files in desktop and mobile web applications. The JavaScript library fetches information about the file and its converted representations through the Box API, chooses the appropriate viewer for the file type, dynamically loads the necessary static assets and file representations, and finally renders the file. Box Content Preview also allows previews of multiple files to be loaded in the same container and exposes arrows to navigate between those files.

This library powers Preview in the main Box web application as well as the 'Get Embed Link' Box API endpoint.

Browser Support

Desktop Chrome, Firefox, Safari, Edge, and Internet Explorer 11
Limited support for mobile web - previews will render but some controls may not work

If you are using Internet Explorer 11, which doesn't natively support promises, include a polyfill.io script (see sample code below) or a Promise library like Bluebird.

Current Version

Version: v1.62.1
Locale: en-US

https://cdn01.boxcdn.net/platform/preview/1.62.1/en-US/preview.js
https://cdn01.boxcdn.net/platform/preview/1.62.1/en-US/preview.css

Supported Locales

To use a different locale, replace en-US in the URLs above with any of the following supported locales.

en-AU, en-CA, en-GB, en-US, bn-IN, da-DK, de-DE, es-419, es-ES, fi-FI, fr-CA, fr-FR, hi-IN,it-IT, ja-JP, ko-KR, nb-NO, nl-NL, pl-PL, pt-BR, ru-RU, sv-SE, tr-TR, zh-CN, zh-TW

Supported File Types

Box Content Preview supports 100+ file types, including most document and image formats, HD video, 3D models, 360-degress images, and 360-degree videos. You can find the full list of supported file types at https://community.box.com/t5/Managing-Your-Content/What-file-types-and-fonts-are-supported-by-Box-s-Content-Preview/ta-p/327#FileTypesSupported.

Usage

Including Preview as a library

You can self-host the Box Content Preview library or reference the versions available on Box's CDN.

<!DOCTYPE html>
<html lang="en-US">
<head>
    <meta charset="utf-8" />
    <title>Box Content Preview Demo</title>

    <!-- polyfill.io only loads a Promise polyfill if your browser needs one -->
    <script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=Promise"></script>

    <!-- Latest version of Preview SDK for your locale -->
    <script src="https://cdn01.boxcdn.net/platform/preview/1.62.1/en-US/preview.js"></script>
    <link rel="stylesheet" href="https://cdn01.boxcdn.net/platform/preview/1.62.1/en-US/preview.css" />
</head>
<body>
    <div class="preview-container" style="height:400px;width:575px"></div>
    <script>
        var preview = new Box.Preview();
        preview.show('93392244621', 'EqFyi1Yq1tD9mxY8F38sxDfp73pFd7FP', {
    	    container: '.preview-container'
        });
    </script>
</body>
</html>

Self-hosting

To self-host the Box Content Preview library, follow these steps:

Either fork the repo and check out the version you want to host or download the specific version as a zip:

Check out a specific version with git checkout v1.62.1
Download a specific version as a zip from https://github.com/box/box-content-preview/releases

Install dependencies and build the library with yarn install && yarn run prod
Self-host everything except for the dev folder from the /dist folder. You must not alter the folder structure and third-party needs to be in the same folder as 1.62.1. For example, if you self-host using a box-assets directory, these URLs must be accessible:

https://cdn.YOUR_SITE.com/box-assets/1.62.1/en-US/preview.js
https://cdn.YOUR_SITE.com/box-assets/third-party/text/0.114.0/papaparse.min.js
https://cdn.YOUR_SITE.com/box-assets/third-party/model3d/1.12.0/three.min.js

Importing Preview as a React Component

Preview can also be used as a React Component with the Box Element framework. The source code for the Content Preview Element wrapper is located at https://github.com/box/box-ui-elements/tree/master/src/components/ContentPreview. Please reference https://github.com/box/box-content-preview-demo for a minimal React application using this wrapper.

CORS (Cross-Origin Resource Sharing)

For security purposes, you must whitelist your application's HTTP origin, omitting any trailing slash, in the configuration section of the Developer Console. For example, CodePen's domain is whitelisted for the demo application below.

Demo

View a demo and sample code on CodePen - http://codepen.io/box-platform/pen/rmZdjm.

Initialization

var preview = new Box.Preview();
preview.show(fileId, accessToken, { options });

Where fileId is a string Box_File id and accessToken is a Box API access token.

Parameters & Options

var preview = new Box.Preview();
preview.show(fileId, accessToken, {
    container: '.preview-container',
    sharedLink: 'https://app.box.com/v/foo',
    sharedLinkPassword: 'bar',
    collection: [FILE_ID, '123', '234', ...],
    header: 'light',
    logoUrl: 'http://i.imgur.com/xh8j3E2.png',
    showAnnotations: true,
    showDownload: true
});

Parameter	Description
fileId	Box file ID
accessToken	Either a string auth token or a token generator function, see below for details

Option	Default	Description
container	document.body	DOM node or selector where Preview should be placed
sharedLink		Shared link URL
sharedLinkPassword		Shared link password
collection		List of file IDs to iterate over for previewing
header	`light`	String value of `none` or `dark` or `light` that controls header visibility and theme
logoUrl		URL of logo to show in header
showAnnotations	false	Whether annotations and annotation controls are shown. This option will be overridden by viewer-specific annotation options if they are set. See Box Annotations for more details
showDownload	false	Whether download button is shown
autoFocus	true	Whether preview should focus itself when a file loads
useHotkeys	true	Whether hotkeys (keyboard shortcuts) are enabled
fixDependencies	false	Temporarily patches AMD to properly load Preview's dependencies. You may need to enable this if your project uses RequireJS
disableEventLog	false	Disables client-side `preview` event log. Previewing with this option enabled will not increment access stats (content access is still logged server-side)
fileOptions	{}	Mapping of file ID to file-level options. See the file option table below for details
previewWMPref	`any`	String value of `all`, `any`, or `none` that sets how previews of watermarked files behave. See https://community.box.com/t5/Sharing-Content-with-Box/Watermarking-Files/ta-p/30766 for more information about watermarking and https://community.box.com/t5/Collaborate-By-Inviting-Others/Understanding-Collaborator-Permission-Levels/ta-p/144 for more information about permissions and collaboration roles. `all` forces watermarked previews. If the file type supports watermarking, users with `can_preview` permissions will see a watermarked preview. If the file type cannot be watermarked, no preview is shown. `any` is the default watermarking behavior in the Box Web Application. If the file type supports watermarking, users with `can_preview` permissions will see a watermarked preview. If the file type cannot be watermarked, users that have both `can_preview` and `can_upload` permissions will see a non-watermarked preview and no preview otherwise. `none` forces non-watermarked previews. Users that have both `can_preview` and `can_upload` permissions will see a non-watermarked preview and no preview otherwise.
downloadWM	false	Whether the download of a watermarked file should be watermarked. This option does not affect non-watermarked files. If true, users will be able to download watermarked versions of supported file types as long as they have `can_preview` permissions (any collaboration role except for `Uploader`).

File Option	Description
fileVersionId	File version ID to preview. This must be a valid non-current file version ID. Use Get Versions to fetch a list of file versions
startAt	Object with unit and value properties indicating where to start the preview at. Current supported units are 'seconds' for media and 'pages' for documents.

Access Token

Box Content Preview needs an access token to make Box API calls. You can either get an access token from the token endpoint (https://developer.box.com/reference#token) or generate a developer token on your application management page (https://blog.box.com/blog/introducing-developer-tokens/).

If your application requires the end user to only be able to access a subset of the Content Preview functionality, you can use Token Exchange to appropriately downscope your App/Managed or Service Account token to a resulting token that has the desired set of permissions, and can thus, be securely passed to the end user client initializing the Content Preview.

Below are a set of new Box Element-specific scopes to go alongside Token Exchange. These allow developers to enable/disable UI controls on the Content Preview by configuring the appropriate scopes on the downscoped token. To learn more, see Special Scopes for Box Elements.

Wish to learn more about when, why and how you can use Token Exchange with the Content Preview? See our blueprint on Customizing Access for the Box Elements.

Base Scope

Scope Name	What permissions does it grant?
base_preview	Allows preview access to a file or files in a folder based on user/file/token permissions

Feature Scopes

Scope Name	What permissions does it grant?
item_download	Allows files/folders contents to be downloaded
annotation_view_self	Allows user to view their own annotations
annotation_view_all	Allows user to view all annotations on the file
annotation_edit	Allows user to edit their own annotations (includes annotation_view_self)

Sample Scenarios

Scenario	Scope Combinations
User wants basic preview functionality + download	base_preview + item_download
User wants basic preview functionality + ability to edit own annotations	base_preview + annotation_edit
User wants basic preview functionality + ability to view all annotations + ability to edit own annotations	base_preview + annotation_view_all + annotation_edit

Token Generator Function

The Preview library optionally takes a token generator function instead of a string token. Using a token generator function allows you to dynamically determine what tokens Preview should use. For example, you can pass in different access tokens for each file or make sure your token is refreshed and valid before showing a preview. The token generator function should return a promise that resolves in either a single string token that applies to all of the files being previewed or a map of typed file IDs to access token for those files.

// Example token generator function that resolves to a single access token
var singleTokenGenerator = function() {
    return someApi.getToken().then(function(data) {
        return data.token;
    });
};

// Example token generator function that resolves to a map of tokens
var mapTokenGenerator = function() {
    return Promise.resolve({
        file_1234: 'some_token_abcd',
        file_2345: 'some_token_bcde'
    });
};

Viewers

The name of a viewer can be one of the following Document, Presentation, MP3, MP4, Dash, Image, Text, SWF, Image360, Video360, Model3d, CSV, Markdown. Call preview.getViewers() to get the list of possible viewers.

Additional Methods

preview.hide() hides the preview.

preview.updateCollection(/* Array[file ids] */ collection) updates the collection to navigate through. Assumes the currently visible file is part of this new collection.

preview.getCurrentCollection() returns the current collection if any.

preview.navigateLeft() shows previous file in the collection.

preview.navigateRight() shows next file in the collection.

preview.navigateToIndex(index) shows the specified index in the current collection.

preview.getCurrentFile() returns the current file being previewed if any. The file object structure is the same as returned by the Box API.

preview.getCurrentViewer() returns the current viewer instance. May be undefined if the viewer isn't ready yet and waiting on conversion to happen.

preview.enableViewers(/* String|Array[String] */ viewers) enables one or more viewers based on VIEWERNAME.

preview.disableViewers(/* String|Array[String] */ viewers) disables one or more viewers based on VIEWERNAME. Viewers can also be disabled by setting disabled: true on the specific viewer option inside options.

preview.enableHotkeys() enables hotkeys (keyboard shortcuts).

preview.disableHotkeys() disables hotkeys (keyboard shortcuts).

preview.print() prints the file if printable.

preview.download() downloads the file if downloadable.

preview.resize() resizes the current preview if applicable. This function only needs to be called when preview's viewport has changed while the window object has not. If the window is resizing, then preview will automatically resize itself.

preview.getViewers() lists all the available viewers.

preview.prefetchViewers(/* Array[String] */) prefetches static assets for the specified viewers that the browser can cache for performance benefits.

Events

The preview object exposes addListener and removeListener for binding to events. Event listeners should be bound before show() is called, otherwise events can be missed.

var preview = new Box.Preview();
var listener = (value) => {
    // Do something with value
};

// Attach listener before calling show otherwise events can be missed
preview.addListener(EVENTNAME, listener);

// Show a preview
preview.show(...);

// Remove listener when appropriate
preview.removeListener(EVENTNAME, listener);

EVENTNAME can be one of the following

viewer event will be fired when we have the viewer instance first available. This will be the same object that is also a property included in the load event. Preview fires this event before load so that clients can attach their listeners before the load event is fired.
load event will be fired on every preview load when show() is called or if inter-preview navigation occurs. The event data will contain:

  {
      error: 'message', // Error message if any error occurred while loading
      viewer: {...},    // Instance of the current viewer object if no error occurred
      metrics: {...},   // Performance metrics
      file: {...}       // Box file object with properties defined in file.js
  }

navigate event will be fired when navigation happens. The event includes the file ID of the file being navigated to, and this event will fire before load.
notification event will be fired when either the preview wrapper or one of the viewers wants to notify something like a warning or non-fatal error. The event data will contain:

  {
      message: 'message', // Message to show
      type: 'warning'    // 'warning', 'notice', or 'error'
  }

viewerevent Each viewer will fire its own sets of events. For example, the Image viewer will fire rotate or resize, etc. while other viewers may fire another set of events. The preview wrapper will also re-emit events at the preview level, with event data containing:

  {
      event: EVENTNAME,         // Event name
      data: DATA,               // Event data object
      viewerName: VIEWERNAME,   // Name of the viewer. See VIEWERNAME above
      fileId: fileId            // The file id
  }

Example event usage

preview.addListener('viewer', (viewer) => {
    viewer.addListener('rotate', () => {
        // Do something when a viewer rotates a preview
    });
});

preview.addListener('load', (data) => {
    var viewer = data.viewer;
    viewer.addListener('rotate', () => {
        // Do something when a viewer rotates a preview
    });
});

preview.addListener('viewerevent', (data) => {
    if (data.viewerName === 'Image') {
        if (data.event === 'rotate') {
            // Do something when an image preview is rotated
        }
    } else if (data.viewerName === 'Image360') {
        if (data.event === 'rotate') {
            // Do something different when a 360-degree image is rotated
        }
    } else {}
});

preview.addListener('rotate', (data) => {
    if (data.viewerName === 'Image') {
        // Do something when an image preview is rotated
    } else if (data.viewerName === 'Image360') {
        // Do something different when a 360-degree image is rotated
    } else {}
});

Development Setup

Install latest LTS version of Node v8.9.4 or higher.
Install yarn package manager https://yarnpkg.com/en/docs/install. Alternatively, you can replace any yarn command with npm.
Fork the upstream repo https://github.com/box/box-content-preview.
Clone your fork locally git clone git@github.com:[YOUR GITHUB USERNAME]/box-content-preview.git.
Navigate to the cloned folder cd box-content-preview
Add the upstream repo to your remotes git remote add upstream git@github.com:box/box-content-preview.git.
Verify your remotes are properly set up git remote -v. You should pull updates from the Box repo upstream and push changes to your fork origin.
Install dependencies yarn install
Test your first build! yarn run build
To automatically rsync files after a Webpack build, add a build/rsync.json file with a location field. This file should look like:

{
    "location": "YOUR_DESIRED_RSYNC_LOCATION_HERE"
}

While Developing

Install the following plugins in your preferred editor

Editor Config (standardizes basic editor configuration)
ESLint (Javascript linting)
Prettier & Prettier - ESLint (Automatic Javascript formatting following ESLint config)
Stylelint (CSS linting)

Yarn commands

yarn run build to generate resource bundles and JS webpack bundles.
yarn run start to only generate JS webpack bundles on file changes.
yarn run start:dev to launch a webpack-dev-server instance for local development.
yarn run test launches karma tests with PhantomJS.
yarn run test -- --src=PATH/TO/SRC/FILENAME launches test only for src/lib/PATH/TO/SRC/__tests__/FILENAME-test.js instead of all tests. For example, yarn run test -- --src=viewers/media/MediaBase launches tests for src/lib/viewers/media/__tests__/MediaBase-test.js. This also works for directories, e.g. yarn run test -- --src=viewers/doc/.
yarn run debug launches karma tests with PhantomJS for debugging. Open the URL mentioned in the console.
yarn run debug -- --src=path/to/src/FILENAME launches debugging for src/lib/path/to/src/__tests__/FILENAME-test.js instead of all tests. Open the URL mentioned in the console.

For more script commands see package.json. Test coverage reports are available under reports/coverage.

Config files

.babelrc - https://babeljs.io/docs/usage/babelrc/
.editorconfig - http://editorconfig.org/
.eslintignore - http://eslint.org/docs/user-guide/configuring#ignoring-files-and-directories
.eslintrc - http://eslint.org/docs/user-guide/configuring
.gitignore - https://git-scm.com/docs/gitignore
.stylelintrc - https://stylelint.io/user-guide/configuration/
.travis.yml - https://docs.travis-ci.com/user/customizing-the-build
browserslist - https://github.com/ai/browserslist
commitlint.config.js - https://github.com/marionebl/commitlint
postcss.config.js - https://github.com/postcss/postcss-loader

Support

If you have any questions, please search our issues list to see if they have been previously answered. Report new issues here.

For general Box Platform, API, and Box Element questions, please visit our developer forum or contact us via one of our available support channels.

Copyright and License

Licensed under the Box Software License Agreement v.20170516. You may not use this file except in compliance with the License. You may obtain a copy of the License at

https://developer.box.com/docs/box-sdk-license

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

pramodsum/box-content-preview