Synnefo

# Copyright 2011-2012 GRNET S.A. All rights reserved.

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#      disclaimer.

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#      disclaimer in the documentation and/or other materials

#      provided with the distribution.

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# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS

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from django.db import IntegrityError, transaction

from django.core.exceptions import ObjectDoesNotExist

from functools import wraps

from smtplib import SMTPException

from astakos.im.models import (

    AstakosUser, AstakosGroup, GroupKind, Resource, Service, RESOURCE_SEPARATOR

)

from astakos.im.api.backends.base import BaseBackend, SuccessResult, FailureResult

from astakos.im.api.backends.errors import (

    ItemNotExists, ItemExists, MissingIdentifier, MultipleItemsExist

)

from astakos.im.util import reserved_email, model_to_dict

from astakos.im.endpoints.quotaholder import get_quota

import logging

logger = logging.getLogger(__name__)

DEFAULT_CONTENT_TYPE = None

def safe(func):

    """Decorator function for views that implement an API method."""

    @transaction.commit_manually

    @wraps(func)

    def wrapper(self, *args, **kwargs):

        logger.debug('%s %s %s' % (func, args, kwargs))

        try:

            data = func(self, *args, **kwargs) or ()

        except Exception, e:

            logger.exception(e)

            transaction.rollback()

            return FailureResult(getattr(e, 'message', e))

        else:

            transaction.commit()

            return SuccessResult(data)

    return wrapper

class DjangoBackend(BaseBackend):

    def _lookup_object(self, model, **kwargs):

        """

        Returns an object of the specific model matching the given lookup

        parameters.

        """

        if not kwargs:

            raise MissingIdentifier

        try:

            return model.objects.get(**kwargs)

        except model.DoesNotExist:

            raise ItemNotExists(model._meta.verbose_name, **kwargs)

        except model.MultipleObjectsReturned:

            raise MultipleItemsExist(model._meta.verbose_name, **kwargs)

    def _lookup_user(self, id):

        """

        Returns an AstakosUser having this id.

        """

        if not isinstance(id, int):

            raise TypeError('User id should be of type int')

        return self._lookup_object(AstakosUser, id=id)

    def _lookup_service(self, id):

        """

        Returns an Service having this id.

        """

        if not isinstance(id, int):

            raise TypeError('Service id should be of type int')

        return self._lookup_object(Service, id=id)

    def _list(self, model, filter=()):

        q = model.objects.all()

        if filter:

            q = q.filter(id__in=filter)

        return map(lambda o: model_to_dict(o, exclude=[]), q)

    def _create_object(self, model, **kwargs):

        o = model.objects.create(**kwargs)

        o.save()

        return o

    def _update_object(self, model, id, save=True, **kwargs):

        o = self._lookup_object(model, id=id)

        if kwargs:

            o.__dict__.update(kwargs)

        if save:

            o.save()

        return o

    @safe

    def update_user(self, user_id, renew_token=False, **kwargs):

        user = self._update_object(AstakosUser, user_id, save=False, **kwargs)

        if renew_token:

            user.renew_token()

        if kwargs or renew_token:

            user.save()

    @safe

    def create_user(self, **kwargs):

        policies = kwargs.pop('policies', ())

        permissions = kwargs.pop('permissions', ())

        groups = kwargs.pop('groups', ())

        password = kwargs.pop('password', None)

        u = self._create_object(AstakosUser, **kwargs)

        if password:

            u.set_password(password)

        u.permissions = permissions

        u.policies = policies

        u.extended_groups = groups

        return self._list(AstakosUser, filter=(u.id,))

    @safe

    def add_policies(self, user_id, update=False, policies=()):

        user = self._lookup_user(user_id)

        rejected = []

        append = rejected.append

        for p in policies:

            service = p.get('service')

            resource = p.get('resource')

            uplimit = p.get('uplimit')

            try:

                user.add_policy(service, resource, uplimit, update)

            except (ObjectDoesNotExist, IntegrityError), e:

                append((service, resource, e))

        return rejected

    @safe

    def remove_policies(self, user_id, policies=()):

        user = self._lookup_user(user_id)

        if not user:

            return user_id

        rejected = []

        append = rejected.append

        for p in policies:

            service = p.get('service')

            resource = p.get('resource')

            try:

                user.delete_policy(service, resource)

            except ObjectDoesNotExist, e:

                append((service, resource, e))

        return rejected

    @safe

    def add_permissions(self, user_id, permissions=()):

        user = self._lookup_user(user_id)

        rejected = []

        append = rejected.append

        for p in permissions:

            try:

                user.add_permission(p)

            except IntegrityError, e:

                append((p, e))

        return rejected

    @safe

    def remove_permissions(self, user_id, permissions=()):

        user = self._lookup_user(user_id)

        rejected = []

        append = rejected.append

        for p in permissions:

            try:

                user.remove_permission(p)

            except (ObjectDoesNotExist, IntegrityError), e:

                append((p, e))

        return rejected

    @safe

    def invite_users(self, senderid, recipients=()):

        user = self._lookup_user(senderid)

        rejected = []

        append = rejected.append

        for r in recipients:

            try:

                user.invite(r.get('email'), r.get('realname'))

            except (IntegrityError, SMTPException), e:

                append((email, e))

        return rejected

    @safe

    def list_users(self, filter=()):

        return self._list(AstakosUser, filter=filter)

    @safe

    def get_resource_usage(self, user_id):

        user = self._lookup_user(user_id)

        c, data = get_quota((user,))

        resources = []

        append = resources.append

        for t in data:

            t = (i if i else 0 for i in t)

            (entity, name, quantity, capacity, importLimit, exportLimit,

             imported, exported, returned, released, flags) = t

            service, sep, resource = name.partition(RESOURCE_SEPARATOR)

            resource = Resource.objects.select_related().get(

                service__name=service, name=resource)

            d = dict(name=name,

                     description=resource.desc,

                     unit=resource.unit or '',

                     maxValue=quantity + capacity,

                     currValue=quantity + imported - released - exported + returned)

            append(d)

        return resources

    @safe

    def list_resources(self, filter=()):

        return self._list(Resource, filter=filter)

    @safe

    def create_service(self, **kwargs):

        resources = kwargs.pop('resources', ())

        s = self._create_object(Service, **kwargs)

        s.resources = resources

        return self._list(Service, filter=(s.id,))

    @safe

    def remove_services(self, ids=()):

        # TODO return information for unknown ids

        q = Service.objects.filter(id__in=ids)

        q.delete()

    @safe

    def update_service(self, service_id, renew_token=False, **kwargs):

        s = self._update_object(Service, service_id, save=False, **kwargs)

        if renew_token:

            s.renew_token()

        if kwargs or renew_token:

            s.save()

    @safe

    def add_resources(self, service_id, update=False, resources=()):

        s = self._lookup_service(service_id)

        rejected = []

        append = rejected.append

        for r in resources:

            try:

                rr = r.copy()

                resource_id = rr.pop('id', None)

                if update:

                    if not resource_id:

                        raise MissingIdentifier

                    resource = self._update_object(Resource, resource_id, **rr)

                else:

                    resource = self._create_object(Resource, service=s, **rr)

            except Exception, e:

                append((r, e))

        return rejected

    @safe

    def remove_resources(self, service_id, ids=()):

        # TODO return information for unknown ids

        q = Resource.objects.filter(service__id=service_id,

                                id__in=ids)

        q.delete()

    @safe

    def create_group(self, **kwargs):

        policies = kwargs.pop('policies', ())

        permissions = kwargs.pop('permissions', ())

        members = kwargs.pop('members', ())

        owners = kwargs.pop('owners', ())

        kwargs['kind'] = self._lookup_object(

            GroupKind, name=kwargs.get('kind', 'course')

        )

        g = self._create_object(AstakosGroup, **kwargs)

        g.permissions = permissions

        g.policies = policies

#         g.members = members

        g.owners = owners

        return self._list(AstakosGroup, filter=(g.id,))