firefoxuz / expression-backend-2

Supported Operators:

• Addition: +
• Subtraction: -
• Multiplication: *
• Division: /

Supported Operand Range:

• Positive integers: 0-9

Installation

Follow these steps to set up the Expression Calculator Service and Expression Agent:

Expression Calculator Service

1. Clone the Expression Calculator Service project repository:

   git clone https://github.com/firefoxuz/expression-backend-2.git

2. Navigate to the project directory:

   cd expression-backend-2

3. Copy the example environment configuration file:

   cp .env.json.example .env.json

4. Start the Docker containers using Docker Compose:

   docker-compose up -d

5. Apply database migrations:

   docker run -v ./db/migrations:/migrations --network host migrate/migrate -path=/migrations/ -database postgres://expression_user:expression_password@localhost:5444/expression_db?sslmode=disable up

Expression Agent

6. Clone the Expression Agent project repository:

   git clone https://github.com/firefoxuz/expression-agent-2.git

7. Navigate to the project directory:

   cd expression-agent-2

8. Copy the example environment configuration file:

   cp .env.json.example .env.json

9. Start the Docker containers using Docker Compose:

   docker-compose up -d

Now, both the Expression Calculator Service and Expression Agent should be up and running. You can access the Expression Calculator Service at http://127.0.0.1:8085/ and the Expression Agent at their respective API endpoints.

API Documentation

Register User

Registers a new user with the provided login credentials.

• URL

  /api/v1/register

• Method

  POST

• Request Body

  Field	Type	Description
  login	string	User's username
  password	string	User's password

  Example:

  {
      "login": "username",
      "password": "123456"
  }

• Success Response

  • Code: 200 OK

    {
        "message": "User registered successfully"
    }

• Error Response

  • Code: 400 Bad Request
  • Content:

    {
        "error": "Invalid request body"
    }

User Login

Logs in a user with the provided login credentials.

• URL

  /api/v1/login

• Method

  POST

• Request Body

  Field	Type	Description
  login	string	User's username
  password	string	User's password

  Example:

  {
      "login": "username",
      "password": "123456"
  }

• Success Response

  • Code: 200 OK
  • Content:

    {
        "token_type": "jwt",
        "token": "some_generated_token"
    }

• Error Response

  • Code: 401 Unauthorized
  • Content:

    {
        "error": "Invalid login credentials"
    }

Add Expressions

Adds expressions with a time limit.

• URL

  /api/v1/expressions

• Method

  POST

• Request Headers

  Header	Value
  Content-Type	application/json
  Authorization	Bearer <access_token>

• Request Body

  Field	Type	Description
  expression	string	Mathematical expression
  time_limit	integer	Time limit for expression (ms)

  Example:

  {
      "expression": "3+3+3",
      "time_limit": 1000
  }

• Success Response

  • Code: 200 OK
  • Content:

    {
        "message": "expression is stored and will be calculated"
    }

• Error Response

  • Code: 400 Bad Request
  • Content:

    {
        "error": "Invalid request body"
    }

  OR

  • Code: 401 Unauthorized
  • Content:

    {
        "error": "Unauthorized"
    }

Fetch All User Expressions

Retrieves all expressions stored for the authenticated user.

• URL

  /api/v1/expressions

• Method

  GET

• Request Headers

  Header	Value
  Content-Type	application/json
  Authorization	Bearer <access_token>

• Success Response

  • Code: 200 OK
    • Content:

      {
          "expressions": [
              {
                  "id": 2,
                  "user_id": 1,
                  "expression": "3+3+3",
                  "result": 9,
                  "is_processing": false,
                  "is_time_limit": null,
                  "is_valid": true,
                  "is_finished": true,
                  "time_limit": 1000,
                  "created_at": "2024-04-21T22:11:55Z",
                  "finished_at": "2024-04-21T17:11:57.92291Z"
              },
              {
                  "id": 1,
                  "user_id": 1,
                  "expression": "3+3+3",
                  "result": 9,
                  "is_processing": false,
                  "is_time_limit": null,
                  "is_valid": true,
                  "is_finished": true,
                  "time_limit": 1000,
                  "created_at": "2024-04-21T16:57:30Z",
                  "finished_at": "2024-04-21T17:10:44.748884Z"
              }
          ]
      }

Fetch Expression by ID

Retrieves a single expression by its ID.

• URL

  /api/v1/expressions/{expression_id}

• Method

  GET

• URL Parameters

  Parameter	Type	Description
  expression_id	string	ID of the expression

• Request Headers

  Header	Value
  Authorization	Bearer <access_token>

  • Success Response

    • Code: 200 OK
    • Content:

        {
            "expressions": {
                "id": 2,
                "user_id": 1,
                "expression": "3+3+3",
                "result": 9,
                "is_processing": false,
                "is_time_limit": null,
                "is_valid": true,
                "is_finished": true,
                "time_limit": 1000,
                "created_at": "2024-04-21T22:11:55Z",
                "finished_at": "2024-04-21T17:11:57.92291Z"
            }
        }

• Error Responses

  • Code: 401 Unauthorized Content:

    {
        "error": "Unauthorized"
    }

  • Code: 404 Not Found Content:

    {
        "error": "Expression not found"
    }

Microservice Architecture

Below is the architecture of our microservices: