Synnefo

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from dbworker import DBWorker

from sqlalchemy import Table, Column, String, Integer, Boolean, MetaData

from sqlalchemy.sql import and_, select

from sqlalchemy.schema import Index

from sqlalchemy.exc import NoSuchTableError

from pithos.backends.random_word import get_random_word

from dbworker import ESCAPE_CHAR

import logging

logger = logging.getLogger(__name__)

def create_tables(engine):

    metadata = MetaData()

    columns = []

    columns.append(Column('public_id', Integer, primary_key=True))

    columns.append(Column('path', String(2048), nullable=False))

    columns.append(Column('active', Boolean, nullable=False, default=True))

    columns.append(Column('url', String(2048), nullable=True))

    public = Table('public', metadata, *columns, mysql_engine='InnoDB',

                   sqlite_autoincrement=True)

    # place an index on path

    Index('idx_public_path', public.c.path, unique=True)

    # place an index on url

    Index('idx_public_url', public.c.url, unique=True)

    metadata.create_all(engine)

    return metadata.sorted_tables

class Public(DBWorker):

    """Paths can be marked as public."""

    def __init__(self, **params):

        DBWorker.__init__(self, **params)

        try:

            metadata = MetaData(self.engine)

            self.public = Table('public', metadata, autoload=True)

        except NoSuchTableError:

            tables = create_tables(self.engine)

            map(lambda t: self.__setattr__(t.name, t), tables)

    def get_unique_url(self, public_security, public_url_alphabet):

        l = public_security

        while 1:

            candidate = get_random_word(length=l, alphabet=public_url_alphabet)

            if self.public_path(candidate) is None:

                return candidate

            l +=1

    def public_set(self, path, public_security, public_url_alphabet):

        s = select([self.public.c.public_id])

        s = s.where(self.public.c.path == path)

        r = self.conn.execute(s)

        row = r.fetchone()

        r.close()

        if not row:

            url = self.get_unique_url(

                public_security, public_url_alphabet

            )

            s = self.public.insert()

            s = s.values(path=path, active=True, url=url)

            r = self.conn.execute(s)

            r.close()

            logger.info('Public url: %s set for path: %s' % (url, path))

    def public_unset(self, path):

        s = self.public.delete()

        s = s.where(self.public.c.path == path)

        self.conn.execute(s).close()

        logger.info('Public url unset for path: %s' % (path))

    def public_unset_bulk(self, paths):

        if not paths:

            return

        s = self.public.delete()

        s = s.where(self.public.c.path.in_(paths))

        self.conn.execute(s).close()

    def public_get(self, path):

        s = select([self.public.c.url])

        s = s.where(and_(self.public.c.path == path,

                         self.public.c.active == True))

        r = self.conn.execute(s)

        row = r.fetchone()

        r.close()

        if row:

            return row[0]

        return None

    def public_list(self, prefix):

        s = select([self.public.c.path, self.public.c.url])

        s = s.where(self.public.c.path.like(

            self.escape_like(prefix) + '%', escape=ESCAPE_CHAR))

        s = s.where(self.public.c.active == True)

        r = self.conn.execute(s)

        rows = r.fetchall()

        r.close()

        return rows

    def public_path(self, public):

        s = select([self.public.c.path])

        s = s.where(and_(self.public.c.url == public,

                         self.public.c.active == True))

        r = self.conn.execute(s)

        row = r.fetchone()

        r.close()

        if row:

            return row[0]

        return None