/aws-lambda-image

Automatic image resize/reduce on AWS Lambda

Primary LanguageJavaScriptMIT LicenseMIT

aws-lambda-image

Build Status Code Climate npm version

An AWS Lambda Function to resize/reduce images automatically. When an image is put on AWS S3 bucket, this package will resize/reduce it and put to S3.

Requirements

  • node.js ( AWS Lambda working version is 4.3.2 )
  • make

Installation

Clone this repository and install dependencies:

$ git clone git@github.com:ysugimoto/aws-lambda-image.git
$ cd aws-lambda-image
$ npm install .

Packaging

AWS Lambda accepts zip archived package. To create it, run make lambda task simply.

$ make lambda

It will create aws-lambda-image.zip at project root. You can upload it.

Configuration

This works with config.json put on project root. There is config.json.sample as example. You can copy to use it.

$ cp config.json.sample config.json

Configuration is simple, see below:

{
  "bucket": "your-destination-bucket",
  "reduce": {
      "directory": "reduced",
      "quality": 90
  },
  "resizes": [
    {
      "size": 300,
      "directory": "resized/small"
    },
    {
      "size": "600x600^",
      "gravity": "Center",
      "crop": "600x600",
      "directory": "resized/cropped-to-square"
    },
    {
      "size": 600,
      "directory": "resized/600-jpeg",
      "format": "jpg",
      "background": "white"
    },
    {
      "size": 900,
      "directory": "resized/large",
      "quality": 90
    }
  ]
}
  • bucket: [String] Destination bucket name at S3 to put processed image. If not supplied, it will use same bucket of event source.
  • reduce: [Object] Reduce setting.
    • directory: [String] Image directory path.
    • bucket: [Object] Destination bucket to override. If not supplied, it will use bucket setting.
    • quality: [Number] Determine reduced image quality ( enables only JPG ).
  • resizes: [Array] Resize setting.
    • background: [String] Background color to use for transparent pixels when destination image doesn't support transparency.
    • bucket: [Object] Destination bucket to override. If not supplied, it will use bucket setting.
    • crop: [String] Dimensions to crop the image. See ImageMagick crop documentation.
    • directory: [String] Image directory path.
    • format: [String] Image format override. If not supplied, it will leave the image in original format.
    • gravity: [String] Changes how size and crop. See ImageMagick gravity documentation.
    • quality: [Number] Determine reduced image quality ( enables only JPG ).
    • size: [String] Image dimensions. See ImageMagick geometry documentation.

If you want to check how this works with your configuration, you can use configtest:

$ make configtest

Complete / Failed hooks

You can handle resize/reduce process on success/error result on index.js. ImageProcessor::run will return Promise object, run your original code:

processor.run(config)
.then(function(proceedImages)) {

    // Success case:
    // proceedImages is list of ImageData instance on you configuration

    /* your code here */

    // notify lambda
    context.succeed("OK, numbers of " + proceedImages.length + " images has proceeded.");
})
.catch(function(messages) {

    // Failed case:
    // messages is list of string on error messages

    /* your code here */

    // notify lambda
    context.fail("Woops, image process failed: " + messages);
});

Image resize

  • ImageMagick (installed on AWS Lambda)

Image reduce

  • cjpeg
  • pngquant
  • pngout

License

MIT License.

Author

Yoshiaki Sugimoto

Image credits

Thanks for testing fixture images: