72H Media Library Image Processor #2

CHALLENGE OBJECTIVES

• We are building an image processing (micro) service and in this iteration we want to focus on cropping, rotation, transparency and file format transformation of images.
• The micro service provides a REST API where we can send the multipart/form-data of file and several input parameters. As a response we want to receive the transformed image.

 
TECHNOLOGY STACK

• Node.js
• Typescript
• REST

 
PROJECT MIGRATION

• The attached project package contains two directories: image-processor and lerna-project.
• Image-processor must be migrated into lerna-project/packages/server. Replace all logging with the @enchanted/logger and use @enchanted/tslint for linting.

 
API ENDPOINTS
After this project migration has happened, we need the following API endpoints to be implemented.
 
Cropping- /api/images/crop
Available parameters

• topLeftX: integer. Defines the top left X coordinate of the rectangle cropping area
• topLeftY: integer. Defines the top left Y coordinate of the rectangle cropping area
• bottomRightX: integer. Defines the bottom right X coordinate of the rectangle cropping area
• bottomRightY: integer. Defines the bottom right Y coordinate of the rectangle cropping area

The cropping area rectangle is the part of the image, that shall be returned after transformation.
 
Rotation - /api/images/rotate
Available parameters

• rotation: integer. Defines the angle of rotation of the image. Positive numbers are clockwise, negative are counter-clockwise.

 
Transparency - /api/images/transparency
Available parameters

• opacity: integer. Value between 0 and 100. Defines the opacity of the image. Images must be transformed and return in a file format that supports transparency (preferred is PNG)

 
Cropping - /api/images/convert
Available parameters

• fileType: string. Target filetype, one of the defined Image Types below

 
IMAGE TYPES
At least these image types must be supported: JPG, PNG, TIFF, GIF, WebP, HEIF The endpoint should make sure file with invalid file formats are rejected.
 

TECH REQUIREMENTS

• Programming language used must be node.js written in typescript.
• The provided project skeleton must be used for implementation
• Code must be properly documented
• The provided linting configuration must be used
• Every implemented functionality must be tested by unit-tests
• All packages used for this implementation must be MIT, BSD or Apache 2.0
• Every defined port, host etc. should be put in central variables / configurations for easy re-configuration (if applicable).
• The express based components of this implementation must be based on https://tsed.io/
• tslint must show no errors inside IDE (VSCode) and on Command Line
• Please see the below list of preferred node_modules and stick to it. Exceptions from this list must be provided with a reason.
• Do not use unmaintained or deprecated node_modules
• The existing API documentation needs to be expanded with the new features.
• The existing project must be expanded with the REST APIs required

 
PREFERRED NODE MODULES

• HTTP Requests: Axios
• Logging: @enchanted/logger
• Linting: @enchanted/tslint

 
EXPECTED RESULT

• The service needs to provides API endpoints which accept multipart/form-data as input
• The service accepts a file and the parameters described above
• The service respond to a correct request with the transformed image
• The service provide proper HTTP status codes on error
• All technical requirements mentioned are covered.

Final Submission Guidelines

• Full code that covers all the requirements.
• A detailed README file including information on how to setup and run your application.