Golang Calculator Server

This server is a simple calculator that can evaluate mathematical expressions. It has 1 endpoint, /api/v1/calculate. It gets the expression from POST requests, containing the expression in JSON and returns the result or error in JSON.

Features

• Supports basic arithmetic operations (+, -, *, /, ^) and decimal points
• Handles real numbers and supports parenthesis
• Provides comprehensive error handling

Setup

You must have Golang installed.

1. Clone the Repository: Open your terminal and run the following command to clone the repository:

git clone https://github.com/Barsenick/calculator.git

2. Navigate to the Command Directory:

cd ./cmd

3. Run the Server: Start the calculator server by executing:

go run main.go

Usage

To send requests, open PowerShell and run the command:

 Invoke-RestMethod -Method Post -Uri http://localhost:8080/api/v1/calculate -ContentType 'application/json' -Body '{"expression": "5*(22.5+2.5")-2^3}'

Returns: {"result":"117"}.

Error 422

If the expression is not valid, the server will return error 422.

 Invoke-RestMethod -Method Post -Uri http://localhost:8080/api/v1/calculate -ContentType 'application/json' -Body '{"expression": "2+++2"}'

Returns: {"error":"invalid expression"}.

Error 500

If an internal error occurs during the calculation, the server will return error 500.

 Invoke-RestMethod -Method Post -Uri http://localhost:8080/api/v1/calculate -ContentType 'application/json' -Body '{"expression": "1+9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999"}'

Returns: {"error":"internal server error"} (the number is too big for float64).