sagifogel/cats-todo-backend

Todo-Backend implementation using cats, http4s and circe

cats-todo-backend

Todo-Backend implementation using cats, http4s and circe

A sample project of a microservice using cats, http4s, doobie and circe.

The microservice allows CRUD of todo items with a description and enables the option to mark todo as done.

Database

h2 is used as a database. This is an in memory database, so when stopping the application, the state of the microservice is lost.

The following are prerequisites to running the application:

1. Scala 2.13
2. Java 8
3. sbt

Running:

• Via sbt: sbt "project core" run
• Via IDEA:
  • Load the project
  • Refresh sbt dependencies
  • Go to "Edit Configuration"
  • Select the + sign to add a new app (or just CTRL + SHIFT + F9 on the Main file of modules.core):
    • Main class: com.github.sagifogel.todo.Main
    • Program arguments: should be the path to your data generation executable
    • Use classpath on module: core.cats-todo-backend-core
    • JRE: should be 1.8 (Java 8)

Tests:

You can test the microservice with sbt "project tests" test in the terminal

Querying the data API

After running the service, the process starts an HTTP service which by default binds to "0.0.0.0:8080". If you'd like to change the IP or port, this can be configured via the application.conf, and a restart to the service.

Endpoints exposed:

1. List all todo items:

   • URL: [IP:Port]/v1/todos/
   • Verb: GET

2. Add todo:

   • URL: [IP:Port]/v1/todos/
   • Verb: POST
   • Payload:

   {
     "$schema": "http://json-schema.org/draft-04/schema#",
     "type": "object",
     "properties": {
       "description": {
         "type": "string"
       },
       "completed": {
         "type": "boolean"
       }
     },
     "required": [
       "description",
       "completed"
     ]
   }

3. Update todo:

   • URL: [IP:Port]/v1/todos/{uuid}

   • Verb: PUT

   • Payload:

     {
       "$schema": "http://json-schema.org/draft-04/schema#",
       "type": "object",
       "properties": {
         "description": {
           "type": "string"
         },
         "completed": {
           "type": "boolean"
         }
       },
       "required": [
         "description",
         "completed"
       ]
     }

4. Mark todo as done:

   • URL: [IP:Port]/v1/todos/{uuid}/done
   • Verb: PUT

5. Delete specific todo item:

   • URL: [IP:Port]/v1/todos/{uuid}
   • Verb: DELETE

6. Delete all todo items:

• URL: [IP:Port]/v1/todos/
• Verb: DELETE