Source code for flask_store.sqla

# -*- coding: utf-8 -*-


Custom SQLAlchemy types for handling Flask-Store instances in SQLAlchemy.

    import sqlalchemy
except ImportError:

from flask_store import Provider
from flask_store.exceptions import NotConfiguredError
from werkzeug.datastructures import FileStorage

[docs]class FlaskStoreType(sqlalchemy.types.TypeDecorator): """ A SQL Alchemy custom type which will save a file using the Flask Application Configured Store Provider and saves the relative path the the database. Also creates a fresh provider instance when accessing the data attribute from an instance. Example ------- .. sourcecode:: python from flask import Flask from flask_sqlalchemy import SQLAlchemy from flask_store import Store from flask_store.sqla import FlaskStoreType app = Flask(__name__) db = SQLAlchemy(app) store = Store(app) class MyModel(db.Model): field = db.Column(FlaskStoreType(location='/some/place')) """ #: Implements a standard unicode type impl = sqlalchemy.Unicode(256) def __init__(self, max_length=256, location=None, *args, **kwargs): """ Contructor, sets the location of the file relative from the base path. """ if not SQLALCHEMY_INSTALLED: raise NotConfiguredError( 'You need to install sqlalchemy to use the FlaskStoreType') self.location = location super(FlaskStoreType, self).__init__(*args, **kwargs) self.impl = sqlalchemy.types.Unicode(max_length)
[docs] def process_bind_param(self, value, dialect): """ Called when setting the value be stored in the database field, this will be the files relative file path. Arguments --------- value : werkzeug.datastructures.FileStorage The uploaded file to save dialect : sqlalchemy.engine.interfaces.Dialect The dialect Returns ------- str The files realtive path on what ever storage backend defined in the Flask Application configuration """ if not isinstance(value, FileStorage) or not value.filename: return None provider = Provider(value, location=self.location) return provider.relative_path
[docs] def process_result_value(self, value, dialect): """ Called when accessing the value from the database and returning the appropriate provider file wrapper. Arguments --------- value : str The stored relative path in the database dialect : sqlalchemy.engine.interfaces.Dialect The dialect Returns ------- obj An instance of the Store Provider class """ if not value: return None provider = Provider(value, location=self.location) return provider