---

This framework is designed to validate request params for Flask web framework.

It has the following unique features:

• Cross Field and Cross Struct validations
• Array and Map diving, which allows any or all levels of a multidimensional field to be validated
• Customizable error response

Install

you can simply install it by PyPi:

pip install pre-request

Document

pre-request manual could be found at: https://pre-request.readthedocs.io/en/master/index.html

A Simple Example

This is very easy to use pre-request in your project

from flask import Flask

from pre_request import pre, Rule

app = Flask(__name__)

args = {
   "userId": Rule(type=int, required=True)
}

@app.route("/")
@pre.catch(args)
def hello_world(params):
   from flask import g
   return str(params == g.params)

what happened in this code ?

1. Use pre-request library to import a global object pre
2. Define request params rule, e.g. userId must be type of int and required
3. Use @pre.catch(req_params) to filter input value
4. Use ~flask.g or def hello_world(params) to get formatted input value。

Complex Example

We use a very complex example to show the powerful of this framework. Otherwise you can find amount of examples at: https://github.com/Eastwu5788/pre-request/tree/master/examples

from flask import Flask
from pre_request import pre, Rule

args = {
    "userFirst": {
        "userId": Rule(type=int, required=False),
        "socialInfo": {
            "gender": Rule(type=int, enum=[1, 2], default=1),
            "age": Rule(type=int, gte=18, lt=80),
            "country": Rule(required=True, deep=False)
        }
    },
    "userSecond": {
        "userId": Rule(type=int, required=False, neq_key="userFirst.userId"),
        "friends": Rule(type=dict, required=True, multi=True, structure={
            "userId": Rule(type=int, required=True, dest="user_id"),
            "userName": Rule(type=str, required=True, dest="user_name")
        })
    }
}


app = Flask(__name__)
app.config["TESTING"] = True
client = app.test_client()

@app.route("/structure", methods=["GET", "POST"])
@pre.catch(args)
def structure_handler(params):
    return str(params)


if __name__ == "__main__":
    resp = app.test_client().post("/structure", json={
        "userFirst": {
            "userId": "13",
            "socialInfo": {
                "age": 20,
            }
        },
        "userSecond": {
            "userId": 14,
            "friends": [
                {
                    "userId": 13,
                    "userName": "Trump"
                }
            ]
        },
        "country": "CN",
        "userFirst.socialInfo.gender": 1
    })

    print(resp.get_data(as_text=True))

Use parse

We can use function pre.parse instead of decorator @pre.catch()

args = {
    "params": Rule(email=True)
}

@app.errorhandler(ParamsValueError)
def params_value_error(e):
    return pre.fmt_resp(e)


@app.route("/index")
def example_handler():
    rst = pre.parse(args)
    return str(rst)

Contributing

How to make a contribution to Pre-request, see the contributing.

Coffee

Please give me a cup of coffee, thank you!

BTC: 1657DRJUyfMyz41pdJfpeoNpz23ghMLVM3

ETH: 0xb098600a9a4572a4894dce31471c46f1f290b087

Links

• Documentaion: https://pre-request.readthedocs.io/en/master/index.html
• Release: https://pypi.org/project/pre-request/
• Code: https://github.com/Eastwu5788/pre-request
• Issue tracker: https://github.com/Eastwu5788/pre-request/issues
• Test status: https://coveralls.io/github/Eastwu5788/pre-request