Synnefo » Pithos

#!/usr/bin/env python

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from sqlalchemy import create_engine

from sqlalchemy import Table, Column, String, MetaData

from sqlalchemy.sql import select

from django.conf import settings

from pithos.backends.modular import ModularBackend

class Migration(object):

    def __init__(self, db):

        self.engine = create_engine(db)

        self.metadata = MetaData(self.engine)

        #self.engine.echo = True

        self.conn = self.engine.connect()

        options = getattr(settings, 'BACKEND', None)[1]

        self.backend = ModularBackend(*options)

    def execute(self):

        pass

class Cache():

    def __init__(self, db):

        self.engine = create_engine(db)

        metadata = MetaData(self.engine)

        columns=[]

        columns.append(Column('path', String(2048), primary_key=True))

        columns.append(Column('hash', String(255)))

        self.files = Table('files', metadata, *columns)

        self.conn = self.engine.connect()

        self.engine.echo = True

        metadata.create_all(self.engine)

    def put(self, path, hash):

        # Insert or replace.

        s = self.files.delete().where(self.files.c.path==path)

        r = self.conn.execute(s)

        r.close()

        s = self.files.insert()

        r = self.conn.execute(s, {'path': path, 'hash': hash})

        r.close()

    def get(self, path):

        s = select([self.files.c.hash], self.files.c.path == path)

        r = self.conn.execute(s)

        l = r.fetchone()

        r.close()

        if not l:

            return l

        return l[0]