aws-lambda-image

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 0.10.26 )
• 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"
  },
  "resizes": [
    {
      "size": 300,
      "directory": "resized/small"
    },
    {
      "size": 600,
      "directory": "resized/middle"
    },
    {
      "size": 900,
      "directory": "resized/large"
    }
  ]
}

• 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.
• resizes: [Array] Resize setting.
  • size: [Number] Image width.
  • directory: [String] Image directory path.
  • bucket: [Object] Destination bucket to override. If not supplied, it will use bucket setting.

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:

• http://pngimg.com/
• https://www.pakutaso.com/