@imageproc/cloud-functions

Process images on Google Cloud Storage when images are created.

How to use?

1. Prepare your Google Cloud Functions directory.

functions
  |- package.json
  |- index.js
  |- .gcloudignore
 ...

2. Install @imageproc/cloud-functions

npm install @imageproc/cloud-functions

3. Handle stroage trigger

You can use handleStorageObjectCreated(params: InitParams) to initialize trigger. The followings are the property of InitParams:

• sourceBucket?: string
  • Source bucket of images
  • This is optional property. If not set, use trigger bucket as the source bucket.
• destBucket?: string
  • Destination bucket of generated images
  • This is optional property. If not set, use trigger bucket as the source bucket.
• ignoreNamePattern?: RegExp
  • Pattern of object name to be ignored.
  • If sourceBucket and destBucket is same, this property is REQUIRED to avoid infinite loop processing.
• destNamePrefix?: string
  • Prefix of destination object name
• destNameTransform?: (sourceName: string) => void
  • Function to transfrom object name
  • If this property is set, destNamePrefix property will be ignored.
• operation: Operation
  • Type of image processing
  • name: resizeAspectFit
    • params: ResizeAspectFitParams
  • name: resizeCrop
    • params: ResizeCropParams
  • name: convertFormat
    • params: ConvertFormatParams

Examples:

• Using event target bucket for both source and destination.

const imageproc = require("@imageproc/cloud-functions");
// foo.jpg => files/foo.jpg
exports.processImage = imageproc.handleStorageObjectCreated({
    ignorePattern: /^files\//,
    destNamePrefix: "files/",
    opration: {
        name: "resizeAspectFit",
        params: {
            maxWidth: 2000,
            maxHeight: 2000,
            noScaleUp: true
        }
    }
});

• Using other buckets for source and destination.

const imageproc = require("@imageproc/cloud-functions");
exports.processImage = imageproc.handleStorageObjectCreated({
    sourceBucket: "source-image",
    destBucket: "dest-images",
    ...
});

4. Deploy

gcloud functions deploy processImage \
--runtime nodejs10 \
--trigger-resource YOUR_BUCKET \
--trigger-event google.storage.object.finalize \
--memory 2048MB \ # recommended
--project YOUR_PROJECT