Fast API Project

A FastAPI application for building modern APIs with Python.

This project is build to learn FastAPI, a Python framework. It exposes several dummy APIs just for testing.

Project Structure

fast-api/
├── app/
│   ├── __init__.py
│   ├── main.py
│   ├── routes.py
│   └── services/
│       ├── __init__.py
│       └── data_modification.py
├── main.py
├── requirements.txt
└── README.md

Installation

1. Clone the repository:

git clone https://github.com/klemontea/fast-api.git
cd fast-api

2. Create a virtual environment:

python -m venv venv
source venv/bin/activate  # On Windows: venv\Scripts\activate

3. Install dependencies:

pip install -r requirements.txt

Running the Application

python main.py

The API will be available at http://localhost:8000

API Documentation

• Interactive API docs: http://localhost:8000/docs
• Alternative API docs: http://localhost:8000/redoc

API Endpoints

1. GET /

Root endpoint that returns a welcome message.

2. POST /modify-data

Modify source file data using reference file mapping. This endpoint performs data transformation by applying a reference mapping table to a target column in the source file.

Request Parameters (multipart/form-data):

• source_file (file): Excel file containing the data to be modified
  • Must have headers in the first row
• reference_file (file): Excel file with mapping rules
  • Must contain 3 columns: KEY, AS-IS, TO-BE
  • KEY: Mapping identifier (used to filter which mappings to apply)
  • AS-IS: Original value to find in the target column
  • TO-BE: New value to replace the original value with
• key (string): The mapping key to filter the reference file
• target (string): The column name in the source file to apply the mapping

Example:

POST /modify-data
- source_file: data.xlsx (contains columns like "Status", "Category", etc.)
- reference_file: mapping.xlsx (contains KEY, AS-IS, TO-BE columns)
- key: "status_mapping"
- target: "Status"

Response:

• Success: Returns the modified Excel file as a download
• Error: Returns JSON with error message and available options

Example Use Case: If your source file has a "Status" column with values like "Active", "Inactive", and your reference file has mappings for key "status_mapping" that map "Active" → "Yes" and "Inactive" → "No", this endpoint will return a modified file with the transformations applied.

Requirements

See requirements.txt for the list of dependencies.

Testing

I prefer to use Postman to test the APIs. If you want to use it, you must download Postman first. Alternatively, you can test the APIs via http://localhost:8000/docs. It is more simpler, but has limited capabilities compared to Postman.