Metadata-Version: 2.1
Name: Flask-Parameter-Validation
Version: 2.0.4
Summary: Get and validate all Flask input parameters with ease.
Home-page: https://github.com/Ge0rg3/flask-parameter-validation
Author: George Omnet
Author-email: flaskparametervalidation@georgeom.net
License: MIT
Platform: any
Classifier: Environment :: Web Environment
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: MIT License
Classifier: Operating System :: OS Independent
Classifier: Programming Language :: Python
Classifier: Topic :: Internet :: WWW/HTTP :: Dynamic Content
Classifier: Topic :: Software Development :: Libraries :: Python Modules
Description-Content-Type: text/markdown

# Flask Parameter Validation
### Get and validate all Flask input parameters with ease.

## Install
* Pip: Install with `pip install flask_parameter_validation`.
* Manually:
  - `git clone https://github.com/Ge0rg3/flask-parameter-validation.git`
  - `python setup.py install`


## Simple Usage
```py
from flask import Flask
from typing import List, Optional
from flask_parameter_validation import ValidateParameters, Route, Json, Query

app = Flask(__name__)


@app.route("/update/<int:id>", methods=["POST"])
@ValidateParameters()
def hello(
        id: int = Route(),
        username: str = Json(min_str_length=5, blacklist="<>"),
        age: int = Json(min_int=18, max_int=99),
        nicknames: List[str] = Json(),
        password_expiry: Optional[int] = Json(5),
        is_admin: bool = Query(False)
     ):
    return "Hello World!"


if __name__ == "__main__":
    app.run()
```

## Detailed Usage
1. We use the ValidateParameters decorator on all functions that this modules should be used in.
2. The format for arguments is as follows:
`parameter_name: parameter_type = Class()`
In this example, `parameter_name` would be the field name itself, such as "username". `parameter_type` would be the expected python data type, such as str, int, List, Union etc. Finally, `Class()` is one of the class inputs, as detailed below:

### Classes
1. Route()  
This is the data passed through the URL, such as `/users/<int:id>`
2. Form()  
This is the data passed by a normal HTML form, often with x-www-form-urlencoded content-type.
3. Json()  
This is any JSON body sent -- request must have application/json content type for flask to read this.
4. Query()  
This covers query parameters (aka GET parameters), such as `/news/article?id=55`
5. File()  
The validation on files are different to the others, but file input can still be obtained here as their Flask FileStorage objects.

### Validation
All parameters can have default values, and automatic validation.  
`Route`, `Form`, `Json` and `Query` have the following options:
* default: any, Specifies the default value for the field.
* min_str_length: int, Specifies the minimum character length for a string input
* max_str_length: int, Specifies the maximum character length for a string input
* min_list_length: int, Specifies the minimum number of elements in a list
* max_list_length: int, Specifies the maximum number of elements in a list
* min_int: int, Specifies the minimum number for an int input
* max_int: int, Specifies the maximum number for an int input
* whitelist: str, A string containing allowed characters for the value
* blacklist: str, A string containing forbidden characters for the value
* pattern: str, A regex pattern to test for string matches

`File` has the following options:
* content_types: array of strings, an array of allowed content types.
* min_length: Minimum content-length for a file
* max_length: Maximum content-length for a file

These validators are passed into the classes in the route function, such as:
* `username: str = Json("defaultusername", min_length=5)`
* `profile_picture: Any = File(content_types=["image/png", "image/jpeg"])`
* `filter: str = Query()`

### Overwriting default errors
By default, the error messages are returned as a JSON response, with the detailed error in the "error" field. However, this can be edited by passing a custom error function into the ValidateParameters decorator. For example:
```py
def error_handler(err):
    error_name = type(err)
    error_parameters = err.args
    error_message = str(err)
    return {
        "error_name": type(err).__name__,
        "error_parameters": err.args,
        "error_message": str(err)
    }, 400

@ValidateParameters(error_handler)
def api(...)
```

