# Flask-Hashids
Hashids integration for Flask applications, it is based on the [Hashid](https://github.com/davidaurelio/hashids-python) package available on [PyPi](https://pypi.org/project/hashids/). With this extension you can conveniently use integer ids for your application logic or database tables and hash them before exposing it in URLs or JSON data.
## Installation
The latest stable version [is available on PyPI](https://pypi.org/project/Flask-Hashids/). Either add `Flask-Hashids` to your `requirements.txt` file or install with pip:
```
pip install Flask-Hashids
```
## Configuration
Flask-Hashids is configured through the standard Flask config API. These are the available options:
- **HASHIDS_ALPHABET**: Read more about that in [Hashids documentation](https://github.com/davidaurelio/hashids-python#using-a-custom-alphabet)
- **HASHIDS_MIN_LENGTH**: Read more about that in [Hashids documentation](https://github.com/davidaurelio/hashids-python#controlling-hash-length)
- **SECRET_KEY**: Used as the salt, read more in [Hashids documentation](https://github.com/davidaurelio/hashids-python#using-a-custom-salt)
## Examples
You can find more detailed examples on how to use Flask-Hashids in the examples directory.
```python
from flask import Flask, jsonify, url_for
from flask_hashids import HashidMixin, Hashids
from flask_sqlalchemy import SQLAlchemy
app = Flask(__name__)
app.config['SECRET_KEY'] = 'secret!'
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite://'
db = SQLAlchemy(app)
hashids = Hashids(app)
# The HashidMixin class adds the hashid property which will compute a hashid
# based on the existing id attribute of the instance.
# NOTE: The id attribute must be an int
class User(HashidMixin, db.Model):
__tablename__ = 'users'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(64), nullable=False)
@property
def url(self):
# The HashidConverter encodes the given id to a hashid in the URL
return url_for('user', user_id=self.id)
def to_json(self):
return {'id': self.hashid, 'name': self.name, 'url': self.url}
@app.before_first_request
def database_setup():
db.create_all()
john = User(name='John')
db.session.add(john)
jane = User(name='Jane')
db.session.add(jane)
db.session.commit()
@app.route('/users')
def users():
return [user.to_json() for user in User.query.all()], 200
@app.route('/users/<hashid:user_id>')
def user(user_id: int):
# The HashidConverter decodes the given hashid to an int
user = User.query.get(user_id)
if user is None:
return jsonify('User not found'), 404
return user.to_json(), 200
def main():
# You can encode and decode hashids manually
id = 123
encoded_id = hashids.encode(id)
decoded_id = hashids.decode(encoded_id)
app.run()
if __name__ == '__main__':
main()
```
## Resources
- https://hashids.org/python/
