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

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import logging

import calendar

import inflect

engine = inflect.engine()

from urllib import quote

from functools import wraps

from datetime import datetime

from synnefo.lib.ordereddict import OrderedDict

from django_tables2 import RequestConfig

from django.shortcuts import get_object_or_404

from django.contrib import messages

from django.contrib.auth.decorators import login_required

from django.core.urlresolvers import reverse

from django.db import transaction

from django.db.utils import IntegrityError

from django.http import (

    HttpResponse, HttpResponseBadRequest,

    HttpResponseForbidden, HttpResponseRedirect,

    HttpResponseBadRequest, Http404)

from django.shortcuts import redirect

from django.template import RequestContext, loader as template_loader

from django.utils.http import urlencode

from django.utils.html import escape

from django.utils.safestring import mark_safe

from django.utils.translation import ugettext as _

from django.views.generic.create_update import (

    apply_extra_context, lookup_object, delete_object, get_model_and_form_class)

from django.views.generic.list_detail import object_list, object_detail

from django.core.xheaders import populate_xheaders

from django.core.exceptions import ValidationError, PermissionDenied

from django.template.loader import render_to_string

from django.views.decorators.http import require_http_methods

from django.db.models import Q

from django.core.exceptions import PermissionDenied

from django.utils import simplejson as json

from django.contrib.auth.views import redirect_to_login

import astakos.im.messages as astakos_messages

from astakos.im import activation_backends

from astakos.im import tables

from astakos.im.models import (

    AstakosUser, ApprovalTerms,

    EmailChange, AstakosUserAuthProvider, PendingThirdPartyUser,

    ProjectApplication, ProjectMembership, Project, Service, Resource)

from astakos.im.util import (

    get_context, prepare_response, get_query, restrict_next, model_to_dict)

from astakos.im.forms import (

    LoginForm, InvitationForm,

    FeedbackForm, SignApprovalTermsForm,

    EmailChangeForm,

    ProjectApplicationForm, ProjectSortForm,

    AddProjectMembersForm, ProjectSearchForm,

    ProjectMembersSortForm)

from astakos.im.forms import ExtendedProfileForm as ProfileForm

from astakos.im.functions import (

    send_feedback,

    logout as auth_logout,

    invite as invite_func,

    qh_add_pending_app,

    accept_membership, reject_membership, remove_membership, cancel_membership,

    leave_project, join_project, enroll_member, can_join_request,

    can_leave_request,

    get_related_project_id, get_by_chain_or_404,

    approve_application, deny_application,

    cancel_application, dismiss_application)

from astakos.im.settings import (

    COOKIE_DOMAIN, LOGOUT_NEXT,

    LOGGING_LEVEL, PAGINATE_BY,

    PAGINATE_BY_ALL,

    ACTIVATION_REDIRECT_URL,

    MODERATION_ENABLED)

from astakos.im import presentation

from astakos.im import settings

from astakos.im import auth_providers as auth

from snf_django.lib.db.transaction import commit_on_success_strict

from astakos.im.ctx import ExceptionHandler

from astakos.im import quotas

logger = logging.getLogger(__name__)

def render_response(template, tab=None, status=200, context_instance=None, **kwargs):

    """

    Calls ``django.template.loader.render_to_string`` with an additional ``tab``

    keyword argument and returns an ``django.http.HttpResponse`` with the

    specified ``status``.

    """

    if tab is None:

        tab = template.partition('_')[0].partition('.html')[0]

    kwargs.setdefault('tab', tab)

    html = template_loader.render_to_string(

        template, kwargs, context_instance=context_instance)

    response = HttpResponse(html, status=status)

    return response

def requires_auth_provider(provider_id, **perms):

    """

    """

    def decorator(func, *args, **kwargs):

        @wraps(func)

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

            provider = auth.get_provider(provider_id)

            if not provider or not provider.is_active():

                raise PermissionDenied

            for pkey, value in perms.iteritems():

                attr = 'get_%s_policy' % pkey.lower()

                if getattr(provider, attr) != value:

                    #TODO: add session message

                    return HttpResponseRedirect(reverse('login'))

            return func(request, *args)

        return wrapper

    return decorator

def requires_anonymous(func):

    """

    Decorator checkes whether the request.user is not Anonymous and in that case

    redirects to `logout`.

    """

    @wraps(func)

    def wrapper(request, *args):

        if not request.user.is_anonymous():

            next = urlencode({'next': request.build_absolute_uri()})

            logout_uri = reverse(logout) + '?' + next

            return HttpResponseRedirect(logout_uri)

        return func(request, *args)

    return wrapper

def signed_terms_required(func):

    """

    Decorator checks whether the request.user is Anonymous and in that case

    redirects to `logout`.

    """

    @wraps(func)

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

        if request.user.is_authenticated() and not request.user.signed_terms:

            params = urlencode({'next': request.build_absolute_uri(),

                                'show_form': ''})

            terms_uri = reverse('latest_terms') + '?' + params

            return HttpResponseRedirect(terms_uri)

        return func(request, *args, **kwargs)

    return wrapper

def required_auth_methods_assigned(allow_access=False):

    """

    Decorator that checks whether the request.user has all required auth providers

    assigned.

    """

    def decorator(func):

        @wraps(func)

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

            if request.user.is_authenticated():

                missing = request.user.missing_required_providers()

                if missing:

                    for provider in missing:

                        messages.error(request,

                                       provider.get_required_msg)

                    if not allow_access:

                        return HttpResponseRedirect(reverse('edit_profile'))

            return func(request, *args, **kwargs)

        return wrapper

    return decorator

def valid_astakos_user_required(func):

    return signed_terms_required(required_auth_methods_assigned()(login_required(func)))

@require_http_methods(["GET", "POST"])

@signed_terms_required

def index(request, login_template_name='im/login.html', profile_template_name='im/profile.html', extra_context=None):

    """

    If there is logged on user renders the profile page otherwise renders login page.

    **Arguments**

    ``login_template_name``

        A custom login template to use. This is optional; if not specified,

        this will default to ``im/login.html``.

    ``profile_template_name``

        A custom profile template to use. This is optional; if not specified,

        this will default to ``im/profile.html``.

    ``extra_context``

        An dictionary of variables to add to the template context.

    **Template:**

    im/profile.html or im/login.html or ``template_name`` keyword argument.

    """

    extra_context = extra_context or {}

    template_name = login_template_name

    if request.user.is_authenticated():

        return HttpResponseRedirect(reverse('astakos.im.views.edit_profile'))

    third_party_token = request.GET.get('key', False)

    if third_party_token:

        messages.info(request, astakos_messages.AUTH_PROVIDER_LOGIN_TO_ADD)

    return render_response(

        template_name,

        login_form = LoginForm(request=request),

        context_instance = get_context(request, extra_context)

    )

@require_http_methods(["POST"])

@valid_astakos_user_required

def update_token(request):

    """

    Update api token view.

    """

    user = request.user

    user.renew_token()

    user.save()

    messages.success(request, astakos_messages.TOKEN_UPDATED)

    return HttpResponseRedirect(reverse('edit_profile'))

@require_http_methods(["GET", "POST"])

@valid_astakos_user_required

@transaction.commit_manually

def invite(request, template_name='im/invitations.html', extra_context=None):

    """

    Allows a user to invite somebody else.

    In case of GET request renders a form for providing the invitee information.

    In case of POST checks whether the user has not run out of invitations and then

    sends an invitation email to singup to the service.

    The view uses commit_manually decorator in order to ensure the number of the

    user invitations is going to be updated only if the email has been successfully sent.

    If the user isn't logged in, redirects to settings.LOGIN_URL.

    **Arguments**

    ``template_name``

        A custom template to use. This is optional; if not specified,

        this will default to ``im/invitations.html``.

    ``extra_context``

        An dictionary of variables to add to the template context.

    **Template:**

    im/invitations.html or ``template_name`` keyword argument.

    **Settings:**

    The view expectes the following settings are defined:

    * LOGIN_URL: login uri

    """

    extra_context = extra_context or {}

    status = None

    message = None

    form = InvitationForm()

    inviter = request.user

    if request.method == 'POST':

        form = InvitationForm(request.POST)

        if inviter.invitations > 0:

            if form.is_valid():

                try:

                    email = form.cleaned_data.get('username')

                    realname = form.cleaned_data.get('realname')

                    invite_func(inviter, email, realname)

                    message = _(astakos_messages.INVITATION_SENT) % locals()

                    messages.success(request, message)

                except Exception, e:

                    transaction.rollback()

                    raise

                else:

                    transaction.commit()

        else:

            message = _(astakos_messages.MAX_INVITATION_NUMBER_REACHED)

            messages.error(request, message)

    sent = [{'email': inv.username,

             'realname': inv.realname,

             'is_consumed': inv.is_consumed}

            for inv in request.user.invitations_sent.all()]

    kwargs = {'inviter': inviter,

              'sent': sent}

    context = get_context(request, extra_context, **kwargs)

    return render_response(template_name,

                           invitation_form=form,

                           context_instance=context)

@require_http_methods(["GET", "POST"])

@required_auth_methods_assigned(allow_access=True)

@login_required

@signed_terms_required

def edit_profile(request, template_name='im/profile.html', extra_context=None):

    """

    Allows a user to edit his/her profile.

    In case of GET request renders a form for displaying the user information.

    In case of POST updates the user informantion and redirects to ``next``

    url parameter if exists.

    If the user isn't logged in, redirects to settings.LOGIN_URL.

    **Arguments**

    ``template_name``

        A custom template to use. This is optional; if not specified,

        this will default to ``im/profile.html``.

    ``extra_context``

        An dictionary of variables to add to the template context.

    **Template:**

    im/profile.html or ``template_name`` keyword argument.

    **Settings:**

    The view expectes the following settings are defined:

    * LOGIN_URL: login uri

    """

    extra_context = extra_context or {}

    form = ProfileForm(

        instance=request.user,

        session_key=request.session.session_key

    )

    extra_context['next'] = request.GET.get('next')

    if request.method == 'POST':

        form = ProfileForm(

            request.POST,

            instance=request.user,

            session_key=request.session.session_key

        )

        if form.is_valid():

            try:

                prev_token = request.user.auth_token

                user = form.save(request=request)

                next = restrict_next(

                    request.POST.get('next'),

                    domain=COOKIE_DOMAIN

                )

                msg = _(astakos_messages.PROFILE_UPDATED)

                messages.success(request, msg)

                if form.email_changed:

                    msg = _(astakos_messages.EMAIL_CHANGE_REGISTERED)

                    messages.success(request, msg)

                if form.password_changed:

                    msg = _(astakos_messages.PASSWORD_CHANGED)

                    messages.success(request, msg)

                if next:

                    return redirect(next)

                else:

                    return redirect(reverse('edit_profile'))

            except ValueError, ve:

                messages.success(request, ve)

    elif request.method == "GET":

        request.user.is_verified = True

        request.user.save()

    # existing providers

    user_providers = request.user.get_enabled_auth_providers()

    user_disabled_providers = request.user.get_disabled_auth_providers()

    # providers that user can add

    user_available_providers = request.user.get_available_auth_providers()

    extra_context['services'] = Service.catalog().values()

    return render_response(template_name,

                           profile_form=form,

                           user_providers=user_providers,

                           user_disabled_providers=user_disabled_providers,

                           user_available_providers=user_available_providers,

                           context_instance=get_context(request,

                                                          extra_context))

@transaction.commit_manually

@require_http_methods(["GET", "POST"])

def signup(request, template_name='im/signup.html', on_success='index',

           extra_context=None, activation_backend=None):

    """

    Allows a user to create a local account.

    In case of GET request renders a form for entering the user information.

    In case of POST handles the signup.

    The user activation will be delegated to the backend specified by the

    ``activation_backend`` keyword argument if present, otherwise to the

    ``astakos.im.activation_backends.InvitationBackend`` if

    settings.ASTAKOS_INVITATIONS_ENABLED is True or

    ``astakos.im.activation_backends.SimpleBackend`` if not (see

    activation_backends);

    Upon successful user creation, if ``next`` url parameter is present the

    user is redirected there otherwise renders the same page with a success

    message.

    On unsuccessful creation, renders ``template_name`` with an error message.

    **Arguments**

    ``template_name``

        A custom template to render. This is optional;

        if not specified, this will default to ``im/signup.html``.

    ``extra_context``

        An dictionary of variables to add to the template context.

    ``on_success``

        Resolvable view name to redirect on registration success.

    **Template:**

    im/signup.html or ``template_name`` keyword argument.

    """

    extra_context = extra_context or {}

    if request.user.is_authenticated():

        logger.info("%s already signed in, redirect to index",

                    request.user.log_display)

        return HttpResponseRedirect(reverse('index'))

    provider = get_query(request).get('provider', 'local')

    if not auth.get_provider(provider).get_create_policy:

        logger.error("%s provider not available for signup", provider)

        raise PermissionDenied

    instance = None

    # user registered using third party provider

    third_party_token = request.REQUEST.get('third_party_token', None)

    unverified = None

    if third_party_token:

        # retreive third party entry. This was created right after the initial

        # third party provider handshake.

        pending = get_object_or_404(PendingThirdPartyUser,

                                    token=third_party_token)

        provider = pending.provider

        # clone third party instance into the corresponding AstakosUser

        instance = pending.get_user_instance()

        get_unverified = AstakosUserAuthProvider.objects.unverified

        # check existing unverified entries

        unverified = get_unverified(pending.provider,

                                    identifier=pending.third_party_identifier)

        if unverified and request.method == 'GET':

            messages.warning(request, unverified.get_pending_registration_msg)

            if unverified.user.moderated:

                messages.warning(request,

                                 unverified.get_pending_resend_activation_msg)

            else:

                messages.warning(request,

                                 unverified.get_pending_moderation_msg)

    # prepare activation backend based on current request

    if not activation_backend:

        activation_backend = activation_backends.get_backend()

    form_kwargs = {'instance': instance}

    if third_party_token:

        form_kwargs['third_party_token'] = third_party_token

    form = activation_backend.get_signup_form(

        provider, None, **form_kwargs)

    if request.method == 'POST':

        form = activation_backend.get_signup_form(

            provider,

            request.POST,

            **form_kwargs)

        if form.is_valid():

            commited = False

            try:

                user = form.save(commit=False)

                # delete previously unverified accounts

                if AstakosUser.objects.user_exists(user.email):

                    AstakosUser.objects.get_by_identifier(user.email).delete()

                # store_user so that user auth providers get initialized

                form.store_user(user, request)

                result = activation_backend.handle_registration(user)

                if result.status == \

                        activation_backend.Result.PENDING_MODERATION:

                    # user should be warned that his account is not active yet

                    status = messages.WARNING

                else:

                    status = messages.SUCCESS

                message = result.message

                activation_backend.send_result_notifications(result, user)

                # commit user entry

                transaction.commit()

                # commited flag

                # in case an exception get raised from this point

                commited = True

                if user and user.is_active:

                    # activation backend directly activated the user

                    # log him in

                    next = request.POST.get('next', '')

                    response = prepare_response(request, user, next=next)

                    return response

                messages.add_message(request, status, message)

                return HttpResponseRedirect(reverse(on_success))

            except Exception, e:

                if not commited:

                    transaction.rollback()

                raise

    return render_response(template_name,

                           signup_form=form,

                           third_party_token=third_party_token,

                           provider=provider,

                           context_instance=get_context(request, extra_context))

@require_http_methods(["GET", "POST"])

@required_auth_methods_assigned(allow_access=True)

@login_required

@signed_terms_required

def feedback(request, template_name='im/feedback.html', email_template_name='im/feedback_mail.txt', extra_context=None):

    """

    Allows a user to send feedback.

    In case of GET request renders a form for providing the feedback information.

    In case of POST sends an email to support team.

    If the user isn't logged in, redirects to settings.LOGIN_URL.

    **Arguments**

    ``template_name``

        A custom template to use. This is optional; if not specified,

        this will default to ``im/feedback.html``.

    ``extra_context``

        An dictionary of variables to add to the template context.

    **Template:**

    im/signup.html or ``template_name`` keyword argument.

    **Settings:**

    * LOGIN_URL: login uri

    """

    extra_context = extra_context or {}

    if request.method == 'GET':

        form = FeedbackForm()

    if request.method == 'POST':

        if not request.user:

            return HttpResponse('Unauthorized', status=401)

        form = FeedbackForm(request.POST)

        if form.is_valid():

            msg = form.cleaned_data['feedback_msg']

            data = form.cleaned_data['feedback_data']

            send_feedback(msg, data, request.user, email_template_name)

            message = _(astakos_messages.FEEDBACK_SENT)

            messages.success(request, message)

            return HttpResponseRedirect(reverse('feedback'))

    return render_response(template_name,

                           feedback_form=form,

                           context_instance=get_context(request,

                                                        extra_context))

@require_http_methods(["GET"])

def logout(request, template='registration/logged_out.html',

           extra_context=None):

    """

    Wraps `django.contrib.auth.logout`.

    """

    extra_context = extra_context or {}

    response = HttpResponse()

    if request.user.is_authenticated():

        email = request.user.email

        auth_logout(request)

    else:

        response['Location'] = reverse('index')

        response.status_code = 301

        return response

    next = restrict_next(

        request.GET.get('next'),

        domain=COOKIE_DOMAIN

    )

    if next:

        response['Location'] = next

        response.status_code = 302

    elif LOGOUT_NEXT:

        response['Location'] = LOGOUT_NEXT

        response.status_code = 301

    else:

        last_provider = request.COOKIES.get('astakos_last_login_method', 'local')

        provider = auth.get_provider(last_provider)

        message = provider.get_logout_success_msg

        extra = provider.get_logout_success_extra_msg

        if extra:

            message += "<br />"  + extra

        messages.success(request, message)

        response['Location'] = reverse('index')

        response.status_code = 301

    return response

@require_http_methods(["GET", "POST"])

@transaction.commit_manually

def activate(request, greeting_email_template_name='im/welcome_email.txt',

             helpdesk_email_template_name='im/helpdesk_notification.txt'):

    """

    Activates the user identified by the ``auth`` request parameter, sends a

    welcome email and renews the user token.

    The view uses commit_manually decorator in order to ensure the user state

    will be updated only if the email will be send successfully.

    """

    token = request.GET.get('auth')

    next = request.GET.get('next')

    if request.user.is_authenticated():

        message = _(astakos_messages.LOGGED_IN_WARNING)

        messages.error(request, message)

        return HttpResponseRedirect(reverse('index'))

    try:

        user = AstakosUser.objects.get(verification_code=token)

    except AstakosUser.DoesNotExist:

        raise Http404

    if user.email_verified:

        message = _(astakos_messages.ACCOUNT_ALREADY_VERIFIED)

        messages.error(request, message)

        return HttpResponseRedirect(reverse('index'))

    try:

        backend = activation_backends.get_backend()

        result = backend.handle_verification(user, token)

        backend.send_result_notifications(result, user)

        next = ACTIVATION_REDIRECT_URL or next

        response = HttpResponseRedirect(reverse('index'))

        if user.is_active:

            response = prepare_response(request, user, next, renew=True)

            messages.success(request, _(result.message))

        else:

            messages.warning(request, _(result.message))

    except Exception:

        transaction.rollback()

        raise

    else:

        transaction.commit()

        return response

@require_http_methods(["GET", "POST"])

def approval_terms(request, term_id=None,

                   template_name='im/approval_terms.html', extra_context=None):

    extra_context = extra_context or {}

    term = None

    terms = None

    if not term_id:

        try:

            term = ApprovalTerms.objects.order_by('-id')[0]

        except IndexError:

            pass

    else:

        try:

            term = ApprovalTerms.objects.get(id=term_id)

        except ApprovalTerms.DoesNotExist, e:

            pass

    if not term:

        messages.error(request, _(astakos_messages.NO_APPROVAL_TERMS))

        return HttpResponseRedirect(reverse('index'))

    try:

        f = open(term.location, 'r')

    except IOError:

        messages.error(request, _(astakos_messages.GENERIC_ERROR))

        return render_response(

            template_name, context_instance=get_context(request,

                                                        extra_context))

    terms = f.read()

    if request.method == 'POST':

        next = restrict_next(

            request.POST.get('next'),

            domain=COOKIE_DOMAIN

        )

        if not next:

            next = reverse('index')

        form = SignApprovalTermsForm(request.POST, instance=request.user)

        if not form.is_valid():

            return render_response(template_name,

                                   terms=terms,

                                   approval_terms_form=form,

                                   context_instance=get_context(request,

                                                                extra_context))

        user = form.save()

        return HttpResponseRedirect(next)

    else:

        form = None

        if request.user.is_authenticated() and not request.user.signed_terms:

            form = SignApprovalTermsForm(instance=request.user)

        return render_response(template_name,

                               terms=terms,

                               approval_terms_form=form,

                               context_instance=get_context(request,

                                                            extra_context))

@require_http_methods(["GET", "POST"])

@transaction.commit_manually

def change_email(request, activation_key=None,

                 email_template_name='registration/email_change_email.txt',

                 form_template_name='registration/email_change_form.html',

                 confirm_template_name='registration/email_change_done.html',

                 extra_context=None):

    extra_context = extra_context or {}

    if not settings.EMAILCHANGE_ENABLED:

        raise PermissionDenied

    if activation_key:

        try:

            user = EmailChange.objects.change_email(activation_key)

            if request.user.is_authenticated() and \

                request.user == user or not \

                    request.user.is_authenticated():

                msg = _(astakos_messages.EMAIL_CHANGED)

                messages.success(request, msg)

                transaction.commit()

                return HttpResponseRedirect(reverse('edit_profile'))

        except ValueError, e:

            messages.error(request, e)

            transaction.rollback()

            return HttpResponseRedirect(reverse('index'))

        return render_response(confirm_template_name,

                               modified_user=user if 'user' in locals()

                               else None, context_instance=get_context(request,

                               extra_context))

    if not request.user.is_authenticated():

        path = quote(request.get_full_path())

        url = request.build_absolute_uri(reverse('index'))

        return HttpResponseRedirect(url + '?next=' + path)

    # clean up expired email changes

    if request.user.email_change_is_pending():

        change = request.user.emailchanges.get()

        if change.activation_key_expired():

            change.delete()

            transaction.commit()

            return HttpResponseRedirect(reverse('email_change'))

    form = EmailChangeForm(request.POST or None)

    if request.method == 'POST' and form.is_valid():

        try:

            ec = form.save(request, email_template_name, request)

        except Exception, e:

            transaction.rollback()

            raise

        else:

            msg = _(astakos_messages.EMAIL_CHANGE_REGISTERED)

            messages.success(request, msg)

            transaction.commit()

            return HttpResponseRedirect(reverse('edit_profile'))

    if request.user.email_change_is_pending():

        messages.warning(request, astakos_messages.PENDING_EMAIL_CHANGE_REQUEST)

    return render_response(

        form_template_name,

        form=form,

        context_instance=get_context(request, extra_context)

    )

def send_activation(request, user_id, template_name='im/login.html',

                    extra_context=None):

    if request.user.is_authenticated():

        return HttpResponseRedirect(reverse('index'))

    extra_context = extra_context or {}

    try:

        u = AstakosUser.objects.get(id=user_id)

    except AstakosUser.DoesNotExist:

        messages.error(request, _(astakos_messages.ACCOUNT_UNKNOWN))

    else:

        if u.email_verified:

            logger.warning("[resend activation] Account already verified: %s",

                           u.log_display)

            messages.error(request,

                           _(astakos_messages.ACCOUNT_ALREADY_VERIFIED))

        else:

            activation_backend = activation_backends.get_backend()

            activation_backend.send_user_verification_email(u)

            messages.success(request, astakos_messages.ACTIVATION_SENT)

    return HttpResponseRedirect(reverse('index'))

@require_http_methods(["GET"])

@valid_astakos_user_required

def resource_usage(request):

    resources_meta = presentation.RESOURCES

    current_usage = quotas.get_user_quotas(request.user)

    current_usage = json.dumps(current_usage['system'])

    resource_catalog, resource_groups = _resources_catalog(for_usage=True)

    if resource_catalog is False:

        # on fail resource_groups contains the result object

        result = resource_groups

        messages.error(request, 'Unable to retrieve system resources: %s' %

                       result.reason)

    resource_catalog = json.dumps(resource_catalog)

    resource_groups = json.dumps(resource_groups)

    resources_order = json.dumps(resources_meta.get('resources_order'))

    return render_response('im/resource_usage.html',

                           context_instance=get_context(request),

                           resource_catalog=resource_catalog,

                           resource_groups=resource_groups,

                           resources_order=resources_order,

                           current_usage=current_usage,

                           token_cookie_name=settings.COOKIE_NAME,

                           usage_update_interval=

                           settings.USAGE_UPDATE_INTERVAL)

# TODO: action only on POST and user should confirm the removal

@require_http_methods(["GET", "POST"])

@valid_astakos_user_required

def remove_auth_provider(request, pk):

    try:

        provider = request.user.auth_providers.get(pk=int(pk)).settings

    except AstakosUserAuthProvider.DoesNotExist:

        raise Http404

    if provider.get_remove_policy:

        messages.success(request, provider.get_removed_msg)

        provider.remove_from_user()

        return HttpResponseRedirect(reverse('edit_profile'))

    else:

        raise PermissionDenied

def how_it_works(request):

    return render_response(

        'im/how_it_works.html',

        context_instance=get_context(request))

@commit_on_success_strict()

def _create_object(request, model=None, template_name=None,

        template_loader=template_loader, extra_context=None, post_save_redirect=None,

        login_required=False, context_processors=None, form_class=None,

        msg=None):

    """

    Based of django.views.generic.create_update.create_object which displays a

    summary page before creating the object.

    """

    response = None

    if extra_context is None: extra_context = {}

    if login_required and not request.user.is_authenticated():

        return redirect_to_login(request.path)

    try:

        model, form_class = get_model_and_form_class(model, form_class)

        extra_context['edit'] = 0

        if request.method == 'POST':

            form = form_class(request.POST, request.FILES)

            if form.is_valid():

                verify = request.GET.get('verify')

                edit = request.GET.get('edit')

                if verify == '1':

                    extra_context['show_form'] = False

                    extra_context['form_data'] = form.cleaned_data

                elif edit == '1':

                    extra_context['show_form'] = True

                else:

                    new_object = form.save()

                    if not msg:

                        msg = _("The %(verbose_name)s was created successfully.")

                    msg = msg % model._meta.__dict__

                    messages.success(request, msg, fail_silently=True)

                    response = redirect(post_save_redirect, new_object)

        else:

            form = form_class()

    except (IOError, PermissionDenied), e:

        messages.error(request, e)

        return None

    else:

        if response == None:

            # Create the template, context, response

            if not template_name:

                template_name = "%s/%s_form.html" %\

                     (model._meta.app_label, model._meta.object_name.lower())

            t = template_loader.get_template(template_name)

            c = RequestContext(request, {

                'form': form

            }, context_processors)

            apply_extra_context(extra_context, c)

            response = HttpResponse(t.render(c))

        return response

@commit_on_success_strict()

def _update_object(request, model=None, object_id=None, slug=None,

        slug_field='slug', template_name=None, template_loader=template_loader,

        extra_context=None, post_save_redirect=None, login_required=False,

        context_processors=None, template_object_name='object',

        form_class=None, msg=None):

    """

    Based of django.views.generic.create_update.update_object which displays a

    summary page before updating the object.

    """

    response = None

    if extra_context is None: extra_context = {}

    if login_required and not request.user.is_authenticated():

        return redirect_to_login(request.path)

    try:

        model, form_class = get_model_and_form_class(model, form_class)

        obj = lookup_object(model, object_id, slug, slug_field)

        if request.method == 'POST':

            form = form_class(request.POST, request.FILES, instance=obj)

            if form.is_valid():

                verify = request.GET.get('verify')

                edit = request.GET.get('edit')

                if verify == '1':

                    extra_context['show_form'] = False

                    extra_context['form_data'] = form.cleaned_data

                elif edit == '1':

                    extra_context['show_form'] = True

                else:

                    obj = form.save()

                    if not msg:

                        msg = _("The %(verbose_name)s was created successfully.")

                    msg = msg % model._meta.__dict__

                    messages.success(request, msg, fail_silently=True)

                    response = redirect(post_save_redirect, obj)

        else:

            form = form_class(instance=obj)

    except (IOError, PermissionDenied), e:

        messages.error(request, e)

        return None

    else:

        if response == None:

            if not template_name:

                template_name = "%s/%s_form.html" %\

                    (model._meta.app_label, model._meta.object_name.lower())

            t = template_loader.get_template(template_name)

            c = RequestContext(request, {

                'form': form,

                template_object_name: obj,

            }, context_processors)

            apply_extra_context(extra_context, c)

            response = HttpResponse(t.render(c))

            populate_xheaders(request, response, model, getattr(obj, obj._meta.pk.attname))

        return response

def _resources_catalog(for_project=False, for_usage=False):

    """

    `resource_catalog` contains a list of tuples. Each tuple contains the group

    key the resource is assigned to and resources list of dicts that contain

    resource information.

    `resource_groups` contains information about the groups

    """

    # presentation data

    resources_meta = presentation.RESOURCES

    resource_groups = resources_meta.get('groups', {})

    resource_catalog = ()

    resource_keys = []

    # resources in database

    resource_details = map(lambda obj: model_to_dict(obj, exclude=[]),

                           Resource.objects.all())

    # initialize resource_catalog to contain all group/resource information

    for r in resource_details:

        if not r.get('group') in resource_groups:

            resource_groups[r.get('group')] = {'icon': 'unknown'}

    resource_keys = [r.get('str_repr') for r in resource_details]

    resource_catalog = [[g, filter(lambda r: r.get('group', '') == g,

                                   resource_details)] for g in resource_groups]

    # order groups, also include unknown groups

    groups_order = resources_meta.get('groups_order')

    for g in resource_groups.keys():

        if not g in groups_order:

            groups_order.append(g)

    # order resources, also include unknown resources

    resources_order = resources_meta.get('resources_order')

    for r in resource_keys:

        if not r in resources_order:

            resources_order.append(r)

    # sort catalog groups

    resource_catalog = sorted(resource_catalog,

                              key=lambda g: groups_order.index(g[0]))

    # sort groups

    def groupindex(g):

        return groups_order.index(g[0])

    resource_groups_list = sorted([(k, v) for k, v in resource_groups.items()],

                                  key=groupindex)

    resource_groups = OrderedDict(resource_groups_list)

    # sort resources

    def resourceindex(r):

        return resources_order.index(r['str_repr'])

    for index, group in enumerate(resource_catalog):

        resource_catalog[index][1] = sorted(resource_catalog[index][1],

                                            key=resourceindex)

        if len(resource_catalog[index][1]) == 0:

            resource_catalog.pop(index)

            for gindex, g in enumerate(resource_groups):

                if g[0] == group[0]:

                    resource_groups.pop(gindex)

    # filter out resources which user cannot request in a project application

    exclude = resources_meta.get('exclude_from_usage', [])

    for group_index, group_resources in enumerate(list(resource_catalog)):

        group, resources = group_resources

        for index, resource in list(enumerate(resources)):

            if for_project and not resource.get('allow_in_projects'):

                resources.remove(resource)

            if resource.get('str_repr') in exclude and for_usage:

                resources.remove(resource)

    # cleanup empty groups

    for group_index, group_resources in enumerate(list(resource_catalog)):

        group, resources = group_resources

        if len(resources) == 0:

            resource_catalog.pop(group_index)

            resource_groups.pop(group)

    return resource_catalog, resource_groups

@require_http_methods(["GET", "POST"])