README.md
# serverless-image-processor
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[](https://github.com/Mercateo/serverless-image-processor/blob/master/LICENSE)
This is a [Serverless](https://serverless.com) starter for an image processing lambda. It will create a Cloudfront Distribution, an API Gateway, a image source Bucket and a Lambda function. It's based on the phenomenal [sharp](https://github.com/lovell/sharp) image manipulation and conversion library.
Request flow is:
User -> Cloudfront -> API Gateway -> Lambda
## Demo
  
https://d1tk3y1sqx2xzp.cloudfront.net/test.png?width=200
https://d1tk3y1sqx2xzp.cloudfront.net/test.jpg?width=200
https://d1tk3y1sqx2xzp.cloudfront.net/test.gif?width=200
## Supported formats
Input: ```image/jpeg```, ```image/png```, ```image/gif```
Output: ```image/jpeg```, ```image/png```, ```image/webp```
## Query params
```typescript
export interface QueryParams {
/**
* The width/height of the output image.
* If you specify only one dimension (width or height) the image will be scaled respecting the ratio.
* If you specify both the image will be croped to the center if possible.
* If nothing is specified the width will default to 1920.
* Allowed values: 1 - 5000
*/
width?: number;
height?: number;
/**
* Do not enlarge the output image if the input image width or height are already less than the required dimensions.
* Default: true
*/
withoutEnlargement?: boolean;
/**
* Preserving aspect ratio, resize the image to the maximum width or height specified then embed on a background of the exact width and height specified.
* Default: false
*/
embed?: boolean;
/**
* Sets the background for embed mode.
* Accepts every string format which is accepted by https://www.npmjs.com/package/color.
* Default: black
*/
background?: string;
/**
* Preserving aspect ratio, resize the image to be as large as possible while ensuring its dimensions are less than or equal to the width and height specified.
* Both width and height must be provided via resize otherwise the behaviour will default to crop.
* Default: false
*/
max?: boolean;
/**
* Converts the input image to jpg.
* Default: false
*/
jpg?: boolean;
/**
* Converts the input image to webp.
* Default: false
*/
webp?: boolean;
/**
* Specifies the output quality for jpg and webp.
* Allowed values: 1 - 100
* Default: 75
*/
quality?: number;
/**
* Specifies if the output is a progressive image.
* Only for jpg and png output.
* Default: true
*/
progressive?: boolean;
/**
* Blur the image.
* Needs a value between 0.3 and 100 representing the sigma of the Gaussian mask, where sigma = 1 + radius / 2.
* Keep in mind higher values will be very slow.
*/
blur?: number;
/**
* If true the output image will be normalized to enhance
* contrast by stretching its luminance to cover the full dynamic range.
* Default: false
*/
normalize?: boolean;
}
```
## Deployment
If you want to deploy this project to AWS please have a look at this documentation https://serverless.com/framework/docs/providers/aws/guide/quick-start/
It should give you a very good starting point.
## Local development
1. ```$ yarn```
2. ```$ yarn start```
That's it! :)
The start command will spin up an offline version of an API Gateway and a local S3 server (via [serverless-offline](https://github.com/dherault/serverless-offline)). After this you can query some test images (test.gif, test.jpg and test.png) via ```http://localhost:3000```.
## Contributing
Please feel free to open issues or create PRs. :)
Just run the test suites (```yarn test``` and ```yarn test:e2e```) and create new tests for added features.
Also make sure you run ```yarn lint``` (and ```yarn lint:fix```) to check for code style issues.
Notice: the end to end tests may fail on your setup. I work on this :/
## A note on updating sharp
```sharp``` is fixed at version ```0.20.1```. If you plan to upgrade please follow [this](http://sharp.dimens.io/en/stable/install/#aws-lambda) guide and place the output in the ```compiled/``` folder.
## Credits
Example photos by Adi Constantin, Michael DePetris, Blake Connally on Unsplash