Simple thumbnail generator service haing below features:

• Upload image (specially PNG)
• Provides the thumbnail for uploaded file

It provides the rest api for uploading images and fetching the associative thumbnails based on python, golang, redis and rabbitmq. Service has 4 main components:

• api
• queue (rabbitmq)
• redis as main data store
• worker (thumbnail generator)

with the help of rest api, user can upload the file using api which then stores the image related data into redis and sends the thumbnail generator task to rabbitmq based queue ImageConverter and our worker which has subscribed to the queue, listens to the messages and proceeds with the thumbnail generator.

Thumbnail
├── README.md
├── api
│   ├── Dockerfile
│   ├── Dockerfile.test
│   ├── gazo
│   │   ├── __init__.py
│   │   ├── api.py
│   │   ├── commands.py
│   │   ├── exceptions.py
│   │   ├── extensions.py
│   │   ├── image
│   │   │   ├── __init__.py
│   │   │   └── index.py
│   │   ├── settings.py
│   │   └── utils.py
│   ├── requirements
│   │   ├── dev.txt
│   │   └── prod.txt
│   ├── requirements.txt
│   ├── run.py
│   └── tests
│       ├── __init__.py
│       ├── __pycache__
│       ├── conftest.py
│       ├── test_get_thumbmail.py
│       ├── test_image_upload.py
│       └── test_utils.py
├── docker-compose.dev.yml
├── docker-compose.test.yml
├── docker-compose.yml
├── rabbitmq
│   ├── Dockerfile
│   ├── definitions.json
│   └── rabbitmq.config
├── run-tests.sh
├── sampledata
│   ├── cologne.png
│   ├── tokyo.jpg
│   ├── tokyo.png
│   ├── wrong.png
│   └── zero_byte.png
└── worker
    ├── Dockerfile
    ├── config
    │   ├── config.go
    │   ├── dev.json
    │   ├── prod.json
    │   └── test.json
    ├── consumer.go
    ├── go.mod
    ├── go.sum
    ├── main.go
    ├── redisdb.go
    └── resizer.go

File uploader endpoint specific to png format

• file (required): type(Content-Type: image/png)> validation cases:
  • PNG with size > 0B or size < 10MB

{
    "request_id" : "XXXXXXXXX"
}

{
    "message" : "XXXXXXXXX"
}

Here are the response codes and messages descriptions

Thumbnail endpoint providing status of thumbnail generation and thumnnail

• request_id (required): type(string)

• thumbnail generation successful

  {
     "request_id": "ba009385-27d2-4e6e-9005-64c45066a23f",
     "thumbnail_status": "COMPLETED",
     "result": {
        "thumbnail_100x100": "http://localhost:5000/image/ba009385-27d2-4e6e-9005-64c45066a23f_100x100.png",
        "original_image": "http://localhost:5000/image/ba009385-27d2-4e6e-9005-64c45066a23f.png"
     }
  }

• thumbnail generation processing request has been submitted to service but still thumbnail generation is not yes finished by worker process

  {
      "request_id": "4a6f11ec-855b-4671-9b69-70ab57685bc9",
      "thumbnail_status": "PROCESSING",
  }

• thumbnail generation failed request has been submitted to service but thumbnail generation is failed by worker process

  {
      "request_id": "97d715cc-16e3-420a-af63-6c0a30c12f44",
      "thumbnail_status": "FAILED",
  }

• 404

  {
      "message" : "No such request registered in system"
  }

• 503

  {
      "message" : "Internal Server Error, Try again later"
  }

Here are the response codes and messages

Provide Thumbnail image

• request_id (required): type(string)

• 200 or 304 (cached) thumbnail image

• 404

  {
      "message" : "File not found"
  }

• 503 service error

Here are the response codes and messages

Development and testing is done on below docker environment

feel free to upgrade your personal computer to work service properly.

Note: make sure your don't have any service running on your local machine with ports 5000,5672,15672,6379 otherwise kill that process for time being

cd Thumbnail
docker-compose up
# wait for all containers to build and start as this is first time exection

• Thumbnail generation successful

  # already some sample data for png,jpg, 0B png are added into sampledata 
  # Open New terminal
  curl -F 'file=@./sampledata/tokyo.png' 127.0.0.1:5000/image
  export reqId=${request_id}
  curl "http://127.0.0.1:5000/image/$reqId/thumbnail"

• Thumbnailgeneration inprogress

   # already some sample data for png,jpg, 0B png are added into sampledata 
   # Open New terminal and go to our project directory `Thumbnail`
   docker-compose stop worker
   curl -F 'file=@./sampledata/cologne.png' 127.0.0.1:5000/image
   export reqId=${request_id}
   curl "http://127.0.0.1:5000/image/$reqId/thumbnail" # this one will have "PROCESSING" thumbnail_status
   docker-compose start worker
   curl "http://127.0.0.1:5000/image/$reqId/thumbnail" # this one will have "COMPLETED" thumbnail_status

• Thumbnailgeneration failed

   # already some sample data for png,jpg, 0B png are added into sampledata 
   # Open New terminal and go to our project directory `Thumbnail` or you can change any files extension to png and make request 
   curl -F 'file=@./sampledata/wrong.png' 127.0.0.1:5000/image
   export reqId=${request_id}
   curl "http://127.0.0.1:5000/image/$reqId/thumbnail" #this one will have "PROCESSING" thumbnail_status

• Bad request_id

   curl "http://127.0.0.1:5000/image/45794930453080-fhdjsf-y54i/thumbnail"

• Internal server error

   # already some sample data for png,jpg, 0B png are added into sampledata 
   # Open New terminal and go to our project directory `Thumbnail`
   curl -F 'file=@./sampledata/cologne.png' 127.0.0.1:5000/image
   export reqId=${request_id}
   docker-compose stop redis
   curl "http://127.0.0.1:5000/image/$reqId/thumbnail" # this gives internal server error
   docker-compose start redis

Remove your container once testing is done executing below command from Thumbnail directory

docker-compose down

Execute test cases using Thumbnail/run-tests.sh script Nore: Make sure your previous docker-compose up should be terminated and executed docker-compose down then execute below commands

cd Thumbnail
chmod +x run-tests.sh
./run-tests.sh