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Last active August 16, 2019 06:04
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Example code for the post "Parsing & Validating JSON in Flask Requests"
from flask import Flask, request, jsonify
from functools import wraps
app = Flask(__name__)
users = []
def required_params(required):
def decorator(fn):
def wrapper(*args, **kwargs):
_json = request.get_json()
missing = [r for r in required.keys()
if r not in _json]
if missing:
response = {
"status": "error",
"message": "Request JSON is missing some required params",
"missing": missing
return jsonify(response), 400
wrong_types = [r for r in required.keys()
if not isinstance(_json[r], required[r])]
if wrong_types:
response = {
"status": "error",
"message": "Data types in the request JSON doesn't match the required format",
"param_types": {k: str(v) for k, v in required.items()}
return jsonify(response), 400
return fn(*args, **kwargs)
return wrapper
return decorator
def hello_world():
return 'Hello World!'
@app.route("/user/", methods=["POST"])
@required_params({"first_name": str, "last_name": str, "age": int, "married": bool})
def add_user():
# here a simple list is used in place of a DB
return "OK", 201
if __name__ == '__main__':
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