Six Ways to Parameterize API Test Data in Python

1. Hard‑code parameters directly in the test script, which is simple but inflexible and hard to maintain.

def test_api_request():
    response = requests.get("http://example.com/api?param=value")
    assert response.status_code == 200

2. Store parameters in a variable or list and iterate over them, suitable for multiple similar requests.

params_list = [{"param": "value1"}, {"param": "value2"}]
for params in params_list:
    response = requests.get("http://example.com/api", params=params)
    assert response.status_code == 200

3. Keep test data in Excel or CSV files and read them with pandas or the csv module, ideal for large or complex datasets.

import pandas as pd
# Read Excel file
dataframe = pd.read_excel("test_data.xlsx")
for index, row in dataframe.iterrows():
    response = requests.get(f"http://example.com/api?param={row['param']}")
    assert response.status_code == 200

4. Use YAML or JSON configuration files to manage test data, which are easy to read, edit, and support nested structures.

import json
with open("test_data.json") as file:
    data = json.load(file)
    for item in data["params"]:
        response = requests.get(f"http://example.com/api?param={item['param']}")
        assert response.status_code == 200

5. Employ the built‑in parameterization features of testing frameworks such as pytest or unittest.

import pytest
@pytest.mark.parametrize("param", ["value1", "value2"])
def test_api_with_param(param):
    response = requests.get(f"http://example.com/api?param={param}")
    assert response.status_code == 200

6. Query a database directly from the test script to obtain parameters in real time.

import sqlite3
connection = sqlite3.connect("test.db")
cursor = connection.cursor()
cursor.execute("SELECT param FROM test_data")
for row in cursor.fetchall():
    response = requests.get(f"http://example.com/api?param={row[0]}")
    assert response.status_code == 200