Use Fabric.js to serialize the canvas with canvas.toJSON(), send that JSON to your application’s API for storage, and fetch it by document ID when reopening. Then pass the retrieved JSON to canvas.loadFromJSON() and wait for its Promise to resolve before rendering. Fabric.js handles the canvas serialization and restoration; your application defines the API, IDs, storage, and access rules.
Save the canvas as JSON
Fabric.js’s toJSON() method returns a JSON-compatible representation of the canvas. You can pass that object to JSON.stringify() for an HTTP request body. Fabric.js also defines toJSON() so that JSON.stringify(canvas) works, but calling toJSON() makes it clear that the value being sent is the serialized document. See the current Canvas API and the core concepts guide.
As an Amazon Associate I earn from qualifying purchases.
const documentJson = canvas.toJSON();The API contract below is an application-level example, not a route or payload format prescribed by Fabric.js. This example posts the canvas JSON directly and assumes that the server responds with an object containing an id:
Recommended Free Tools
const response = await fetch('/api/documents', {
method: 'POST',
headers: { 'Content-Type': 'application/json' },
body: JSON.stringify(documentJson),
});
if (!response.ok) {
throw new Error(`Save failed: ${response.status}`);
}
const { id } = await response.json();Your application can choose a different endpoint, payload envelope, ID format, and database. Validate incoming documents and enforce authentication and ownership checks on the server; a client-supplied document ID or JSON body is not an authorization decision.
#1 Best Overall
- USB-C 2-in-1 storage OTG: The Lexar JumpDrive Dual Drive D40E features USB Type-A and Type-C connectors in a slim, portable form factor for easy device compatibility
- Transfer speeds up to 100MB/s: Based on internal testing, performance may vary depending upon the host device, interface, and usage conditions. 1MB=1,000,000 bytes
- Plug and Play: Widely compatible with USB Type-C smartphones, tablets, laptops, Macs, and traditional Type-A devices, no software installation required. The 360° swivel design allows for easy switching between connectors without the hassle of losing a cap
- Durable & Compact: The Lexar D40E USB memory stick features a metal enclosure, withstands temperatures from 0° to 50° C (32°F to 122°F), and is lightweight at 26g with dimensions of 70.4 x 16.9 x 11.7mm
- Security & Warranty: Securely protects files using an advanced security software solution with 256-bit AES encryption. Backed by a Lexar 3-year limited warranty
Open a saved canvas by document ID
First retrieve the document from your API, then load the returned JSON into the Fabric canvas. The example assumes that GET /api/documents/:id returns the canvas JSON itself. Encoding the ID for use in a URL path avoids treating special characters as path syntax.
const response = await fetch(
`/api/documents/${encodeURIComponent(id)}`
);
if (!response.ok) {
throw new Error(`Could not load document: ${response.status}`);
}
const json = await response.json();
await canvas.loadFromJSON(json);
canvas.requestRenderAll();In the current Fabric.js API, loadFromJSON() accepts a JSON string or an object and returns a Promise. Await it before rendering or letting the rest of your application act on the restored objects. The API’s restoration example also requests a render after loading completes; consult the StaticCanvas API.
Rank #2
- High-speed USB 3.0 performance of up to 150MB/s(1) [(1) Write to drive up to 15x faster than standard USB 2.0 drives (4MB/s); varies by drive capacity. Up to 150MB/s read speed. USB 3.0 port required. Based on internal testing; performance may be lower depending on host device, usage conditions, and other factors; 1MB=1,000,000 bytes]
- Transfer a full-length movie in less than 30 seconds(2) [(2) Based on 1.2GB MPEG-4 video transfer with USB 3.0 host device. Results may vary based on host device, file attributes and other factors]
- Transfer to drive up to 15 times faster than standard USB 2.0 drives(1)
- Sleek, durable metal casing
- Easy-to-use password protection for your private files(3) [(3)Password protection uses 128-bit AES encryption and is supported by Windows 7, Windows 8, Windows 10, and Mac OS X v10.9 plus; Software download required for Mac, visit the SanDisk SecureAccess support page]
Coordinate rapid document switches
If a user selects another document while an earlier fetch or canvas load is still underway, the older operation can finish last and replace the newer selection. The StaticCanvas API recommends aborting loading tasks before beginning another load. Also coordinate your fetches so that a stale response does not initiate a load after a newer selection.
One approach is to abort the previous request and use a monotonically increasing selection token to ignore responses that are already too far along to cancel:
Rank #3
- What You Get - 2 pack 64GB genuine USB 2.0 flash drives, 12-month warranty and lifetime friendly customer service
- Great for All Ages and Purposes – the thumb drives are suitable for storing digital data for school, business or daily usage. Apply to data storage of music, photos, movies and other files
- Easy to Use - Plug and play USB memory stick, no need to install any software. Support Windows 7 / 8 / 10 / Vista / XP / Unix / 2000 / ME / NT Linux and Mac OS, compatible with USB 2.0 and 1.1 ports
- Convenient Design - 360°metal swivel cap with matt surface and ring designed zip drive can protect USB connector, avoid to leave your fingerprint and easily attach to your key chain to avoid from losing and for easy carrying
- Brand Yourself - Brand the flash drive with your company's name and provide company's overview, policies, etc. to the newly joined employees or your customers
let activeController;
let selection = 0;
async function openDocument(id) {
const currentSelection = ++selection;
activeController?.abort();
activeController = new AbortController();
// Cancel an outstanding Fabric.js loading task when supported by
// the installed version and the task is available to your app.
canvas.cancelRequestedRender?.();
try {
const response = await fetch(
`/api/documents/${encodeURIComponent(id)}`,
{ signal: activeController.signal }
);
if (!response.ok) throw new Error(`Load failed: ${response.status}`);
const json = await response.json();
if (currentSelection !== selection) return;
await canvas.loadFromJSON(json);
if (currentSelection === selection) canvas.requestRenderAll();
} catch (error) {
if (error.name !== 'AbortError') throw error;
}
}The cancellation call in this illustrative snippet must match the cancellation API in your installed Fabric.js version; do not assume an optional method exists merely because the version offers task cancellation. The selection check protects against an old fetch completing after a newer choice. For loads already in progress, follow the installed version’s documented cancellation mechanism or otherwise serialize and coordinate the operations.
What the JSON does—and does not—restore
Fabric.js JSON is for restoring canvas visual state. It does not save your application’s controls, event handlers, or behavior. Reattach those after loading, and keep application-specific state such as permissions or workflow rules in the appropriate application layer. The official serialization guide describes JSON export and restoration.
Rank #4
- GOOD VALUE PACKAGE - 1 Pack 32GB Memory Stick USB 2.0 Flash Drives with great cost performance and high quality.
- BIG CAPACITY - The available capacity: 29.10GB-29.8GB, You can save the data of movies, music, photos, designs, programs, manuals, handouts in a high speed.Good performance in digital data storing, transferring and sharing with families, friends, workmates, clients and machines.
- EASY TO USE & PLUG AND WORK - Support windows 7 / 8 / 10 / Vista / XP / 2000 / ME / NT Linux and Mac OS, Compatible with USB2.0 and below.
- TWISTTURN DESIGN & EASY CARRY - The metal clip rotates 360° round the ABS plastic body which with rubber oil skin feeling finish. The capless design can avoid lossing of cap, and providing efficient protection to the USB port.
- WARRANTY & SUPPORT - SIMMAX logo is laser printed on the USB connector surface, our products are of good quality and we promise that any problem about the product within one year since you buy.
Match the code to your Fabric.js version
Use documentation for the major version installed in your project. Current Fabric.js documentation uses a Promise-based loadFromJSON(), so await it as shown above. The Fabric.js v5 API reference includes callback-based examples; do not mix that signature with current Promise-based code. Check your package version and its matching API reference before adapting a snippet.
Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Scan for outdated or missing drivers - takes under a minute3Clear out junk files and repair common Windows errorsKeep the API contract separate from Fabric.js
Fabric.js does not prescribe document routes, a request envelope, database choice, authentication scheme, or ID format. Decide those based on your application. In particular, plan for:
Quick Recap
Best Value
- 【16GB Flash Drive】USB flash drives with 16GB capacity, meet your needs of daily use on work, school, home and travelling for photos, music, videos, files storage and transfer. IMEASON thumb drives can be used to store different files, easy to data backup.
- 【Metal Swivel Cap Design】USB thumb drive is metal swivel cover provides extra protection for the usb thumbdrive connector, no usb drive cap to lose; keychain design makes it easier to carry without worrying lose it.
- 【Wide Compatibility】USB drive supports Windows 7/8/10/11 / Vista / XP / Unix / 2000 / ME / NT Linux and Mac OS, also Supports USB 2.0 and 1.1 ports. USB Stick support TV, desktop, notebook computer, car, audio and other device. The USB Memory Stick is your great data storage and transfer companion with traveling and working.
- 【Easy to use】usb memory stick is plug and play without any software installation. Just simply plug the Flashdrive into the port of your USB-compatible devices such as computer, laptop to start data storage or transmission.
- 【What You Get】16 GB USB Flash Drive Thumb Drive, The default format of the usb storage flash drive is FAT32.
- Validation and limits: Check the JSON structure and enforce request and stored-document size limits appropriate to your service.
- Access control: Authenticate the caller and authorize access to the requested document on every read and write.
- Concurrency and versions: Decide how simultaneous edits or saves are handled, such as with revisions or conflict checks.
- Failure handling: Handle non-success HTTP responses and malformed or unavailable documents without treating them as successfully loaded.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
