imagekit-javascript
v3.0.2
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Javascript SDK for using ImageKit.io in the browser
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ImageKit.io Javascript SDK
Javascript SDK for ImageKit provides URL generation for image & video resizing and provides an interface for file upload. This SDK is lightweight and has no dependency. You can also use this as an ES module.
ImageKit is complete media storage, optimization, and transformation solution that comes with an image and video CDN. It can be integrated with your existing infrastructure - storage like AWS S3, web servers, your CDN, and custom domain names, allowing you to deliver optimized images in minutes with minimal code changes.
Changelog
SDK Version 3.0.0
Breaking changes
1. Overlay syntax update
- In version 3.0.0, we've removed the old overlay syntax parameters for transformations, such as
oi
,ot
,obg
, and more. These parameters are deprecated and will start returning errors when used in URLs. Please migrate to the new layers syntax that supports overlay nesting, provides better positional control, and allows more transformations at the layer level. You can start with examples to learn quickly. - You can migrate to the new layers syntax using the
raw
transformation parameter.
SDK Version 2.0.0
Breaking changes
1. Authentication Process Update:
- Previously, when using client side file upload, the SDK required the
publicKey
andauthenticationEndpoint
parameters during SDK initialization to fetch security parameters (signature
,token
, andexpire
). - In version 2.0.0, we've updated the authentication process for the SDK. As a user of the SDK, you are now responsible for generating the security parameters (
signature
,token
, andexpire
) yourself. This means you no longer need to provide theauthenticationEndpoint
. When using the SDK's upload method, make sure to pass these security parameters explicitly along with other upload options. For guidance on generating these security parameters, please refer to the documentation available here.
Installation
Using npm
Install imagekit-javascript
npm install imagekit-javascript --save
#or
yarn add imagekit-javascript
Now import ImageKit
import ImageKit from "imagekit-javascript"
// or
const ImageKit = require("imagekit-javascript")
Using CDN
You can download a specific version of this SDK from a global CDN.
https://unpkg.com/[email protected]/dist/imagekit.min.js
For the latest version, remove the version number i.e.
https://unpkg.com/imagekit-javascript/dist/imagekit.min.js
Now load it using a <script>
tag.
<script type="text/javascript" src="https://unpkg.com/imagekit-javascript/dist/imagekit.min.js"></script>
Initialization
urlEndpoint
is required to use the SDK. You can get URL-endpoint from your ImageKit dashboard - https://imagekit.io/dashboard#url-endpoints
var imagekit = new ImageKit({
urlEndpoint: "https://ik.imagekit.io/your_imagekit_id"
});
publicKey
parameter is required if you want to use the SDK for client-side file upload. You can get this parameter from the developer section in your ImageKit dashboard - https://imagekit.io/dashboard#developers
var imagekit = new ImageKit({
publicKey: "your_public_api_key",
urlEndpoint: "https://ik.imagekit.io/your_imagekit_id",
});
Note: Do not include your Private Key in any client-side code, including this SDK or its initialization. If you pass the privateKey
parameter while initializing this SDK, it throws an error
Demo Application
The fastest way to get started is by running the demo application in samples/sample-app folder. Follow these steps to run the application locally:
git clone https://github.com/imagekit-developer/imagekit-javascript.git
cd imagekit-javascript
Create a file .env
using sample.env
in the directory samples/sample-app
and fill in your PRIVATE_KEY
, PUBLIC_KEY
and URL_ENDPOINT
from your imageKit dashboard. SERVER_PORT
must also be included as per the sample.env
file.
Now start the sample application by running:
// Run it from the project root
yarn startSampleApp
Usage
You can use this SDK for URL generation and client-side file uploads.
URL Generation
1. Using image path and image hostname or endpoint
This method allows you to create an URL to access a file using the relative file path and the ImageKit URL endpoint (urlEndpoint
). The file can be an image, video, or any other static file supported by ImageKit.
var imageURL = imagekit.url({
path: "/default-image.jpg",
urlEndpoint: "https://ik.imagekit.io/your_imagekit_id/endpoint/",
transformation: [{
"height": "300",
"width": "400"
}]
});
This results in a URL like
https://ik.imagekit.io/your_imagekit_id/endpoint/tr:h-300,w-400/default-image.jpg
2. Using full image URL
This method allows you to add transformation parameters to an absolute URL. For example, if you have configured a custom CNAME and have absolute asset URLs in your database or CMS, you will often need this.
var imageURL = imagekit.url({
src: "https://ik.imagekit.io/your_imagekit_id/endpoint/default-image.jpg",
transformation: [{
"height": "300",
"width": "400"
}]
});
This results in a URL like
https://ik.imagekit.io/your_imagekit_id/endpoint/default-image.jpg?tr=h-300%2Cw-400
The .url()
method accepts the following parameters
| Option | Description |
| :----------------| :----------------------------- |
| urlEndpoint | Optional. The base URL to be appended before the path of the image. If not specified, the URL Endpoint specified at the time of SDK initialization is used. For example, https://ik.imagekit.io/your_imagekit_id/endpoint/ |
| path | Conditional. This is the path at which the image exists. For example, /path/to/image.jpg
. Either the path
or src
parameter needs to be specified for URL generation. |
| src | Conditional. This is the complete URL of an image already mapped to ImageKit. For example, https://ik.imagekit.io/your_imagekit_id/endpoint/path/to/image.jpg
. Either the path
or src
parameter needs to be specified for URL generation. |
| transformation | Optional. An array of objects specifying the transformation to be applied in the URL. The transformation name and the value should be specified as a key-value pair in the object. Different steps of a chained transformation can be specified as different objects of the array. The complete list of supported transformations in the SDK and some examples of using them are given later. If you use a transformation name that is not specified in the SDK, it gets applied as it is in the URL. |
| transformationPostion | Optional. The default value is path
, which places the transformation string as a path parameter in the URL. It can also be specified as query
, which adds the transformation string as the query parameter tr
in the URL. If you use the src
parameter to create the URL, then the transformation string is always added as a query parameter. |
| queryParameters | Optional. These are the other query parameters that you want to add to the final URL. These can be any query parameters and are not necessarily related to ImageKit. Especially useful if you want to add some versioning parameters to your URLs. |
Examples of generating URLs
1. Chained Transformations as a query parameter
var imageURL = imagekit.url({
path: "/default-image.jpg",
urlEndpoint: "https://ik.imagekit.io/your_imagekit_id/endpoint/",
transformation: [{
"height": "300",
"width": "400"
}, {
"rotation": 90
}],
transformationPosition: "query"
});
https://ik.imagekit.io/your_imagekit_id/endpoint/default-image.jpg?tr=h-300%2Cw-400%3Art-90
2. Sharpening and contrast transforms and a progressive JPG image
There are some transforms like Sharpening that can be added to the URL with or without any other value. To use such transforms without specifying a value, specify the value as "-" in the transformation object. Otherwise, specify the value that you want to be added to this transformation.
var imageURL = imagekit.url({
src: "https://ik.imagekit.io/your_imagekit_id/endpoint/default-image.jpg",
transformation: [{
"format": "jpg",
"progressive": "true",
"effectSharpen": "-",
"effectContrast": "1"
}]
});
//Note that because `src` parameter was used, the transformation string gets added as a query parameter `tr`
https://ik.imagekit.io/your_imagekit_id/endpoint/default-image.jpg?tr=f-jpg%2Cpr-true%2Ce-sharpen%2Ce-contrast-1
3. Adding overlays
ImageKit.io enables you to apply overlays to images and videos using the raw parameter with the concept of layers. The raw parameter facilitates incorporating transformations directly in the URL. A layer is a distinct type of transformation that allows you to define an asset to serve as an overlay, along with its positioning and additional transformations.
Text as overlays
You can add any text string over a base video or image using a text layer (l-text).
For example:
var imageURL = imagekit.url({
src: "https://ik.imagekit.io/your_imagekit_id/default-image.jpg",
transformation: [{
"width": 400,
"height": 300
"raw": "l-text,i-Imagekit,fs-50,l-end"
}]
});
Sample Result URL
https://ik.imagekit.io/your_imagekit_id/tr:h-300,w-400,l-text,i-Imagekit,fs-50,l-end/default-image.jpg
Image as overlays
You can add an image over a base video or image using an image layer (l-image).
For example:
var imageURL = imagekit.url({
src: "https://ik.imagekit.io/your_imagekit_id/default-image.jpg",
transformation: [{
"width": 400,
"height": 300
"raw": "l-image,i-default-image.jpg,w-100,b-10_CDDC39,l-end"
}]
});
Sample Result URL
https://ik.imagekit.io/your_imagekit_id/tr:h-300,w-400,l-image,i-default-image.jpg,w-100,b-10_CDDC39,l-end/default-image.jpg
Solid color blocks as overlays
You can add solid color blocks over a base video or image using an image layer (l-image).
For example:
var imageURL = imagekit.url({
src: "https://ik.imagekit.io/your_imagekit_id/img/sample-video.mp4",
transformation: [{
"width": 400,
"height": 300
"raw": "l-image,i-ik_canvas,bg-FF0000,w-300,h-100,l-end"
}]
});
Sample Result URL
https://ik.imagekit.io/your_imagekit_id/tr:h-300,w-400,l-image,i-ik_canvas,bg-FF0000,w-300,h-100,l-end/img/sample-video.mp4
4. Arithmetic expressions in transformations
ImageKit allows use of arithmetic expressions in certain dimension and position-related parameters, making media transformations more flexible and dynamic.
For example:
var imageURL = imagekit.url({
src: "https://ik.imagekit.io/your_imagekit_id/default-image.jpg",
transformation: [{
"width": "iw_div_4",
"height": "ih_div_2",
"border": "cw_mul_0.05_yellow"
}]
});
Sample Result URL
https://ik.imagekit.io/your_imagekit_id/default-image.jpg?tr=w-iw_div_4,h-ih_div_2,b-cw_mul_0.05_yellow
List of supported transformations
See the complete list of transformations supported in ImageKit here. The SDK gives a name to each transformation parameter e.g. height
for h
and width
for w
parameter. It makes your code more readable. If the property does not match any of the following supported options, it is added as it is.
If you want to generate transformations in your application and add them to the URL as it is, use the raw
parameter.
| Supported Transformation Name | Translates to parameter | |-------------------------------|-------------------------| | height | h | | width | w | | aspectRatio | ar | | quality | q | | crop | c | | cropMode | cm | | x | x | | y | y | | focus | fo | | format | f | | radius | r | | background | bg | | border | b | | rotation | rt | | blur | bl | | named | n | | progressive | pr | | lossless | lo | | trim | t | | metadata | md | | colorProfile | cp | | defaultImage | di | | dpr | dpr | | effectSharpen | e-sharpen | | effectUSM | e-usm | | effectContrast | e-contrast | | effectGray | e-grayscale | | effectShadow | e-shadow | | effectGradient | e-gradient | | original | orig | | raw | The string provided in raw will be added in the URL as it is. |
File Upload
The SDK provides a simple interface using the .upload()
method to upload files to the ImageKit Media Library.
The upload()
method requires mandatory file
and the fileName
parameter. In addition, it accepts all the parameters supported by the ImageKit Upload API.
Also, before making an upload request, please ensure you have generated mandatory security parameters: signature
, token
, and expire
. To generate these security parameters, refer to the documentation here. Obtain the parameters using a secure method and pass them, along with the mandatory file
and fileName
parameters, to the upload()
method.
You can pass other parameters supported by the ImageKit upload API using the same parameter name as specified in the upload API documentation. For example, to specify tags for a file at the time of upload, use the tags
parameter as specified in the documentation here.
Sample usage
<form action="#" onsubmit="upload()">
<input type="file" id="file1" />
<input type="submit" />
</form>
<script type="text/javascript" src="../dist/imagekit.js"></script>
<script>
/*
SDK initialization
*/
var imagekit = new ImageKit({
publicKey: "your_public_api_key",
urlEndpoint: "https://ik.imagekit.io/your_imagekit_id",
});
// Upload function internally uses the ImageKit.io javascript SDK
function upload(data) {
var file = document.getElementById("file1");
// Using Callback Function
imagekit.upload({
file: file.files[0],
fileName: "abc1.jpg",
tags: ["tag1"],
token: 'generated_token',
signature: 'generated_signature',
expire: 'generated_expire',
extensions: [
{
name: "aws-auto-tagging",
minConfidence: 80,
maxTags: 10
}
],
transformation: {
pre: 'l-text,i-Imagekit,fs-50,l-end',
post: [
{
type: 'transformation',
value: 'w-100'
}
]
}
}, function(err, result) {
console.log(result);
})
// Using Promises
imagekit.upload({
file: file.files[0],
fileName: "abc1.jpg",
tags: ["tag1"],
token: 'generated_token',
signature: 'generated_signature',
expire: 'generated_expire',
extensions: [
{
name: "aws-auto-tagging",
minConfidence: 80,
maxTags: 10
}
],
transformation: {
pre: 'l-text,i-Imagekit,fs-50,l-end',
post: [
{
type: 'transformation',
value: 'w-100'
}
]
}
}).then(result => {
console.log(result);
}).then(error => {
console.log(error);
})
}
</script>
If the upload succeeds, err
will be null
, and the result
will be the same as what is received from ImageKit's servers.
If the upload fails, err
will be the same as what is received from ImageKit's servers, and the result
will be null.
Tracking upload progress using custom XMLHttpRequest
You can use a custom XMLHttpRequest object as the following to bind progress
or any other events for a customized implementation.
var fileSize = file.files[0].size;
var customXHR = new XMLHttpRequest();
customXHR.upload.addEventListener('progress', function (e) {
if (e.loaded <= fileSize) {
var percent = Math.round(e.loaded / fileSize * 100);
console.log(`Uploaded ${percent}%`);
}
if(e.loaded == e.total){
console.log("Upload done");
}
});
imagekit.upload({
xhr: customXHR,
file: file.files[0],
fileName: "abc1.jpg",
tags: ["tag1"],
token: 'generated_token',
signature: 'generated_signature',
expire: 'generated_expire',
extensions: [
{
name: "aws-auto-tagging",
minConfidence: 80,
maxTags: 10
}
]
}).then(result => {
console.log(result);
}).then(error => {
console.log(error);
})
Access request-id, other response headers, and HTTP status code
You can access $ResponseMetadata
on success or error object to access the HTTP status code and response headers.
// Success
var response = await imagekit.upload({
file: file.files[0],
fileName: "abc1.jpg",
tags: ["tag1"],
token: 'generated_token',
signature: 'generated_signature',
expire: 'generated_expire',
extensions: [
{
name: "aws-auto-tagging",
minConfidence: 80,
maxTags: 10
}
]
});
console.log(response.$ResponseMetadata.statusCode); // 200
// { 'content-length': "300", 'content-type': 'application/json', 'x-request-id': 'ee560df4-d44f-455e-a48e-29dfda49aec5'}
console.log(response.$ResponseMetadata.headers);
// Error
try {
await imagekit.upload({
file: file.files[0],
fileName: "abc1.jpg",
tags: ["tag1"],
token: 'generated_token',
signature: 'generated_signature',
expire: 'generated_expire',
extensions: [
{
name: "aws-auto-tagging",
minConfidence: 80,
maxTags: 10
}
]
});
} catch (ex) {
console.log(response.$ResponseMetadata.statusCode); // 400
// {'content-type': 'application/json', 'x-request-id': 'ee560df4-d44f-455e-a48e-29dfda49aec5'}
console.log(response.$ResponseMetadata.headers);
}