api.py

from flask import Flask, request, jsonify
app = Flask(__name__)

def validate_data_format(data):

    valid_data = True
    messages = []
    
    # Check number of rows in each col
    length = len(data[list(data.keys())[0]])
    for i in list(data.keys())[1:]:
        if length != len(data[i]):
            message = ('Different length of row in col: {i}')
            messages.append(message)   
            valid_data = False

    # Check data types
    

    if valid_data:
        return True
    else:
        return messages



@app.route('/upload', methods = ['POST'])
def post_data():
    data = request.get_json()
    validate_data_format(data)

    return jsonify(data), 200
		
if __name__ == '__main__':
   app.run(debug = True)