Synnefo

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

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# without modification, are permitted provided that the following

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#   1. Redistributions of source code must retain the above

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#      disclaimer.

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#      disclaimer in the documentation and/or other materials

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

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from urlparse import urljoin

from random import random

from datetime import datetime, timedelta

from django import forms

from django.utils.translation import ugettext as _

from django.contrib.auth.forms import (

    UserCreationForm, AuthenticationForm,

    PasswordResetForm, PasswordChangeForm,

    SetPasswordForm)

from django.core.mail import send_mail

from django.contrib.auth.tokens import default_token_generator

from django.template import Context, loader

from django.utils.http import int_to_base36

from django.core.urlresolvers import reverse

from django.utils.safestring import mark_safe

from django.utils.encoding import smart_str

from django.conf import settings

from django.forms.models import fields_for_model

from django.db import transaction

from django.utils.encoding import smart_unicode

from django.core import validators

from django.contrib.auth.models import AnonymousUser

from django.core.exceptions import PermissionDenied

from astakos.im.models import (

    AstakosUser, EmailChange, Invitation,

    Resource, PendingThirdPartyUser, get_latest_terms, RESOURCE_SEPARATOR,

    ProjectApplication, Project)

from astakos.im.settings import (

    INVITATIONS_PER_LEVEL, BASEURL, SITENAME, RECAPTCHA_PRIVATE_KEY,

    RECAPTCHA_ENABLED, DEFAULT_CONTACT_EMAIL, LOGGING_LEVEL,

    PASSWORD_RESET_EMAIL_SUBJECT, NEWPASSWD_INVALIDATE_TOKEN,

    MODERATION_ENABLED, PROJECT_MEMBER_JOIN_POLICIES,

    PROJECT_MEMBER_LEAVE_POLICIES)

from astakos.im.widgets import DummyWidget, RecaptchaWidget

from astakos.im.functions import (

    send_change_email, submit_application, do_accept_membership_checks)

from astakos.im.util import reserved_email, reserved_verified_email, \

                            get_query, model_to_dict

from astakos.im import auth_providers

import astakos.im.messages as astakos_messages

import logging

import hashlib

import recaptcha.client.captcha as captcha

import re

logger = logging.getLogger(__name__)

DOMAIN_VALUE_REGEX = re.compile(

    r'^([a-zA-Z0-9]([a-zA-Z0-9\-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]{2,6}$',

    re.IGNORECASE)

class StoreUserMixin(object):

    def store_user(self, user, request):

        """

        WARNING: this should be wrapped inside a transactional view/method.

        """

        user.save()

        self.post_store_user(user, request)

        return user

    def post_store_user(self, user, request):

        """

        Interface method for descendant backends to be able to do stuff within

        the transaction enabled by store_user.

        """

        pass

class LocalUserCreationForm(UserCreationForm, StoreUserMixin):

    """

    Extends the built in UserCreationForm in several ways:

    * Adds email, first_name, last_name, recaptcha_challenge_field,

    * recaptcha_response_field field.

    * The username field isn't visible and it is assigned a generated id.

    * User created is not active.

    """

    recaptcha_challenge_field = forms.CharField(widget=DummyWidget)

    recaptcha_response_field = forms.CharField(

        widget=RecaptchaWidget, label='')

    class Meta:

        model = AstakosUser

        fields = ("email", "first_name", "last_name",

                  "has_signed_terms", "has_signed_terms")

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

        """

        Changes the order of fields, and removes the username field.

        """

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

        if request:

            self.ip = request.META.get('REMOTE_ADDR',

                                       request.META.get('HTTP_X_REAL_IP', None))

        super(LocalUserCreationForm, self).__init__(*args, **kwargs)

        self.fields.keyOrder = ['email', 'first_name', 'last_name',

                                'password1', 'password2']

        if RECAPTCHA_ENABLED:

            self.fields.keyOrder.extend(['recaptcha_challenge_field',

                                         'recaptcha_response_field', ])

        if get_latest_terms():

            self.fields.keyOrder.append('has_signed_terms')

        if 'has_signed_terms' in self.fields:

            # Overriding field label since we need to apply a link

            # to the terms within the label

            terms_link_html = '<a href="%s" target="_blank">%s</a>' \

                % (reverse('latest_terms'), _("the terms"))

            self.fields['has_signed_terms'].label = \

                mark_safe("I agree with %s" % terms_link_html)

    def clean_email(self):

        email = self.cleaned_data['email']

        if not email:

            raise forms.ValidationError(_(astakos_messages.REQUIRED_FIELD))

        if reserved_verified_email(email):

            raise forms.ValidationError(_(astakos_messages.EMAIL_USED))

        return email

    def clean_has_signed_terms(self):

        has_signed_terms = self.cleaned_data['has_signed_terms']

        if not has_signed_terms:

            raise forms.ValidationError(_(astakos_messages.SIGN_TERMS))

        return has_signed_terms

    def clean_recaptcha_response_field(self):

        if 'recaptcha_challenge_field' in self.cleaned_data:

            self.validate_captcha()

        return self.cleaned_data['recaptcha_response_field']

    def clean_recaptcha_challenge_field(self):

        if 'recaptcha_response_field' in self.cleaned_data:

            self.validate_captcha()

        return self.cleaned_data['recaptcha_challenge_field']

    def validate_captcha(self):

        rcf = self.cleaned_data['recaptcha_challenge_field']

        rrf = self.cleaned_data['recaptcha_response_field']

        check = captcha.submit(rcf, rrf, RECAPTCHA_PRIVATE_KEY, self.ip)

        if not check.is_valid:

            raise forms.ValidationError(_(astakos_messages.CAPTCHA_VALIDATION_ERR))

    def post_store_user(self, user, request):

        """

        Interface method for descendant backends to be able to do stuff within

        the transaction enabled by store_user.

        """

        user.add_auth_provider('local', auth_backend='astakos')

        user.set_password(self.cleaned_data['password1'])

    def save(self, commit=True):

        """

        Saves the email, first_name and last_name properties, after the normal

        save behavior is complete.

        """

        user = super(LocalUserCreationForm, self).save(commit=False)

        user.renew_token()

        if commit:

            user.save()

            logger.log(LOGGING_LEVEL, 'Created user %s' % user.email)

        return user

class InvitedLocalUserCreationForm(LocalUserCreationForm):

    """

    Extends the LocalUserCreationForm: email is readonly.

    """

    class Meta:

        model = AstakosUser

        fields = ("email", "first_name", "last_name", "has_signed_terms")

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

        """

        Changes the order of fields, and removes the username field.

        """

        super(InvitedLocalUserCreationForm, self).__init__(*args, **kwargs)

        #set readonly form fields

        ro = ('email', 'username',)

        for f in ro:

            self.fields[f].widget.attrs['readonly'] = True

    def save(self, commit=True):

        user = super(InvitedLocalUserCreationForm, self).save(commit=False)

        user.set_invitations_level()

        user.email_verified = True

        if commit:

            user.save()

        return user

class ThirdPartyUserCreationForm(forms.ModelForm, StoreUserMixin):

    id = forms.CharField(

        widget=forms.HiddenInput(),

        label='',

        required=False

    )

    third_party_identifier = forms.CharField(

        widget=forms.HiddenInput(),

        label=''

    )

    class Meta:

        model = AstakosUser

        fields = ['id', 'email', 'third_party_identifier',

                  'first_name', 'last_name', 'has_signed_terms']

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

        """

        Changes the order of fields, and removes the username field.

        """

        self.request = kwargs.get('request', None)

        if self.request:

            kwargs.pop('request')

        super(ThirdPartyUserCreationForm, self).__init__(*args, **kwargs)

        if 'has_signed_terms' in self.fields:

            # Overriding field label since we need to apply a link

            # to the terms within the label

            terms_link_html = '<a href="%s" target="_blank">%s</a>' \

                % (reverse('latest_terms'), _("the terms"))

            self.fields['has_signed_terms'].label = \

                    mark_safe("I agree with %s" % terms_link_html)

    def clean_email(self):

        email = self.cleaned_data['email']

        if not email:

            raise forms.ValidationError(_(astakos_messages.REQUIRED_FIELD))

        if reserved_verified_email(email):

            provider = auth_providers.get_provider(self.request.REQUEST.get('provider', 'local'))

            extra_message = _(astakos_messages.EXISTING_EMAIL_THIRD_PARTY_NOTIFICATION) % \

                    (provider.get_title_display, reverse('edit_profile'))

            raise forms.ValidationError(_(astakos_messages.EMAIL_USED) + ' ' + \

                                        extra_message)

        return email

    def clean_has_signed_terms(self):

        has_signed_terms = self.cleaned_data['has_signed_terms']

        if not has_signed_terms:

            raise forms.ValidationError(_(astakos_messages.SIGN_TERMS))

        return has_signed_terms

    def post_store_user(self, user, request):

        pending = PendingThirdPartyUser.objects.get(

                                token=request.POST.get('third_party_token'),

                                third_party_identifier= \

                            self.cleaned_data.get('third_party_identifier'))

        return user.add_pending_auth_provider(pending)

    def save(self, commit=True):

        user = super(ThirdPartyUserCreationForm, self).save(commit=False)

        user.set_unusable_password()

        user.renew_token()

        if commit:

            user.save()

            logger.log(LOGGING_LEVEL, 'Created user %s' % user.email)

        return user

class InvitedThirdPartyUserCreationForm(ThirdPartyUserCreationForm):

    """

    Extends the ThirdPartyUserCreationForm: email is readonly.

    """

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

        """

        Changes the order of fields, and removes the username field.

        """

        super(

            InvitedThirdPartyUserCreationForm, self).__init__(*args, **kwargs)

        #set readonly form fields

        ro = ('email',)

        for f in ro:

            self.fields[f].widget.attrs['readonly'] = True

    def save(self, commit=True):

        user = super(InvitedThirdPartyUserCreationForm, self).save(commit=False)

        user.set_invitation_level()

        user.email_verified = True

        if commit:

            user.save()

        return user

class ShibbolethUserCreationForm(ThirdPartyUserCreationForm):

    additional_email = forms.CharField(

        widget=forms.HiddenInput(), label='', required=False)

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

        super(ShibbolethUserCreationForm, self).__init__(*args, **kwargs)

        # copy email value to additional_mail in case user will change it

        name = 'email'

        field = self.fields[name]

        self.initial['additional_email'] = self.initial.get(name, field.initial)

        self.initial['email'] = None

class InvitedShibbolethUserCreationForm(ShibbolethUserCreationForm,

                                        InvitedThirdPartyUserCreationForm):

    pass

class LoginForm(AuthenticationForm):

    username = forms.EmailField(label=_("Email"))

    recaptcha_challenge_field = forms.CharField(widget=DummyWidget)

    recaptcha_response_field = forms.CharField(

        widget=RecaptchaWidget, label='')

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

        was_limited = kwargs.get('was_limited', False)

        request = kwargs.get('request', None)

        if request:

            self.ip = request.META.get('REMOTE_ADDR',

                                       request.META.get('HTTP_X_REAL_IP', None))

        t = ('request', 'was_limited')

        for elem in t:

            if elem in kwargs.keys():

                kwargs.pop(elem)

        super(LoginForm, self).__init__(*args, **kwargs)

        self.fields.keyOrder = ['username', 'password']

        if was_limited and RECAPTCHA_ENABLED:

            self.fields.keyOrder.extend(['recaptcha_challenge_field',

                                         'recaptcha_response_field', ])

    def clean_username(self):

        return self.cleaned_data['username'].lower()

    def clean_recaptcha_response_field(self):

        if 'recaptcha_challenge_field' in self.cleaned_data:

            self.validate_captcha()

        return self.cleaned_data['recaptcha_response_field']

    def clean_recaptcha_challenge_field(self):

        if 'recaptcha_response_field' in self.cleaned_data:

            self.validate_captcha()

        return self.cleaned_data['recaptcha_challenge_field']

    def validate_captcha(self):

        rcf = self.cleaned_data['recaptcha_challenge_field']

        rrf = self.cleaned_data['recaptcha_response_field']

        check = captcha.submit(rcf, rrf, RECAPTCHA_PRIVATE_KEY, self.ip)

        if not check.is_valid:

            raise forms.ValidationError(_(astakos_messages.CAPTCHA_VALIDATION_ERR))

    def clean(self):

        """

        Override default behavior in order to check user's activation later

        """

        username = self.cleaned_data.get('username')

        if username:

            try:

                user = AstakosUser.objects.get_by_identifier(username)

                if not user.has_auth_provider('local'):

                    provider = auth_providers.get_provider('local')

                    raise forms.ValidationError(

                        _(provider.get_message('NOT_ACTIVE_FOR_USER')))

            except AstakosUser.DoesNotExist:

                pass

        try:

            super(LoginForm, self).clean()

        except forms.ValidationError, e:

            if self.user_cache is None:

                raise

            if not self.user_cache.is_active:

                raise forms.ValidationError(self.user_cache.get_inactive_message())

            if self.request:

                if not self.request.session.test_cookie_worked():

                    raise

        return self.cleaned_data

class ProfileForm(forms.ModelForm):

    """

    Subclass of ``ModelForm`` for permiting user to edit his/her profile.

    Most of the fields are readonly since the user is not allowed to change

    them.

    The class defines a save method which sets ``is_verified`` to True so as the

    user during the next login will not to be redirected to profile page.

    """

    renew = forms.BooleanField(label='Renew token', required=False)

    class Meta:

        model = AstakosUser

        fields = ('email', 'first_name', 'last_name', 'auth_token',

                  'auth_token_expires')

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

        self.session_key = kwargs.pop('session_key', None)

        super(ProfileForm, self).__init__(*args, **kwargs)

        instance = getattr(self, 'instance', None)

        ro_fields = ('email', 'auth_token', 'auth_token_expires')

        if instance and instance.id:

            for field in ro_fields:

                self.fields[field].widget.attrs['readonly'] = True

    def save(self, commit=True):

        user = super(ProfileForm, self).save(commit=False)

        user.is_verified = True

        if self.cleaned_data.get('renew'):

            user.renew_token(

                flush_sessions=True,

                current_key=self.session_key

            )

        if commit:

            user.save()

        return user

class FeedbackForm(forms.Form):

    """

    Form for writing feedback.

    """

    feedback_msg = forms.CharField(widget=forms.Textarea, label=u'Message')

    feedback_data = forms.CharField(widget=forms.HiddenInput(), label='',

                                    required=False)

class SendInvitationForm(forms.Form):

    """

    Form for sending an invitations

    """

    email = forms.EmailField(required=True, label='Email address')

    first_name = forms.EmailField(label='First name')

    last_name = forms.EmailField(label='Last name')

class ExtendedPasswordResetForm(PasswordResetForm):

    """

    Extends PasswordResetForm by overriding

    save method: to pass a custom from_email in send_mail.

    clean_email: to handle local auth provider checks

    """

    def clean_email(self):

        email = super(ExtendedPasswordResetForm, self).clean_email()

        try:

            user = AstakosUser.objects.get_by_identifier(email)

            if not user.is_active:

                raise forms.ValidationError(_(astakos_messages.ACCOUNT_INACTIVE))

            if not user.has_usable_password():

                raise forms.ValidationError(_(astakos_messages.UNUSABLE_PASSWORD))

            if not user.can_change_password():

                raise forms.ValidationError(_(astakos_messages.AUTH_PROVIDER_CANNOT_CHANGE_PASSWORD))

        except AstakosUser.DoesNotExist, e:

            raise forms.ValidationError(_(astakos_messages.EMAIL_UNKNOWN))

        return email

    def save(

        self, domain_override=None, email_template_name='registration/password_reset_email.html',

            use_https=False, token_generator=default_token_generator, request=None):

        """

        Generates a one-use only link for resetting password and sends to the user.

        """

        for user in self.users_cache:

            url = user.astakosuser.get_password_reset_url(token_generator)

            url = urljoin(BASEURL, url)

            t = loader.get_template(email_template_name)

            c = {

                'email': user.email,

                'url': url,

                'site_name': SITENAME,

                'user': user,

                'baseurl': BASEURL,

                'support': DEFAULT_CONTACT_EMAIL

            }

            from_email = settings.SERVER_EMAIL

            send_mail(_(PASSWORD_RESET_EMAIL_SUBJECT),

                      t.render(Context(c)), from_email, [user.email])

class EmailChangeForm(forms.ModelForm):

    class Meta:

        model = EmailChange

        fields = ('new_email_address',)

    def clean_new_email_address(self):

        addr = self.cleaned_data['new_email_address']

        if reserved_verified_email(addr):

            raise forms.ValidationError(_(astakos_messages.EMAIL_USED))

        return addr

    def save(self, email_template_name, request, commit=True):

        ec = super(EmailChangeForm, self).save(commit=False)

        ec.user = request.user

        activation_key = hashlib.sha1(

            str(random()) + smart_str(ec.new_email_address))

        ec.activation_key = activation_key.hexdigest()

        if commit:

            ec.save()

        send_change_email(ec, request, email_template_name=email_template_name)

class SignApprovalTermsForm(forms.ModelForm):

    class Meta:

        model = AstakosUser

        fields = ("has_signed_terms",)

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

        super(SignApprovalTermsForm, self).__init__(*args, **kwargs)

    def clean_has_signed_terms(self):

        has_signed_terms = self.cleaned_data['has_signed_terms']

        if not has_signed_terms:

            raise forms.ValidationError(_(astakos_messages.SIGN_TERMS))

        return has_signed_terms

class InvitationForm(forms.ModelForm):

    username = forms.EmailField(label=_("Email"))

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

        super(InvitationForm, self).__init__(*args, **kwargs)

    class Meta:

        model = Invitation

        fields = ('username', 'realname')

    def clean_username(self):

        username = self.cleaned_data['username']

        try:

            Invitation.objects.get(username=username)

            raise forms.ValidationError(_(astakos_messages.INVITATION_EMAIL_EXISTS))

        except Invitation.DoesNotExist:

            pass

        return username

class ExtendedPasswordChangeForm(PasswordChangeForm):

    """

    Extends PasswordChangeForm by enabling user

    to optionally renew also the token.

    """

    if not NEWPASSWD_INVALIDATE_TOKEN:

        renew = forms.BooleanField(label='Renew token', required=False,

                                   initial=True,

                                   help_text='Unsetting this may result in security risk.')

    def __init__(self, user, *args, **kwargs):

        self.session_key = kwargs.pop('session_key', None)

        super(ExtendedPasswordChangeForm, self).__init__(user, *args, **kwargs)

    def save(self, commit=True):

        try:

            if NEWPASSWD_INVALIDATE_TOKEN or self.cleaned_data.get('renew'):

                self.user.renew_token()

            self.user.flush_sessions(current_key=self.session_key)

        except AttributeError:

            # if user model does has not such methods

            pass

        return super(ExtendedPasswordChangeForm, self).save(commit=commit)

class ExtendedSetPasswordForm(SetPasswordForm):

    """

    Extends SetPasswordForm by enabling user

    to optionally renew also the token.

    """

    if not NEWPASSWD_INVALIDATE_TOKEN:

        renew = forms.BooleanField(

            label='Renew token',

            required=False,

            initial=True,

            help_text='Unsetting this may result in security risk.')

    def __init__(self, user, *args, **kwargs):

        super(ExtendedSetPasswordForm, self).__init__(user, *args, **kwargs)

    @transaction.commit_on_success()

    def save(self, commit=True):

        try:

            self.user = AstakosUser.objects.get(id=self.user.id)

            if NEWPASSWD_INVALIDATE_TOKEN or self.cleaned_data.get('renew'):

                self.user.renew_token()

            #self.user.flush_sessions()

            if not self.user.has_auth_provider('local'):

                self.user.add_auth_provider('local', auth_backend='astakos')

        except BaseException, e:

            logger.exception(e)

        return super(ExtendedSetPasswordForm, self).save(commit=commit)

app_name_label       =  "Project name"

app_name_placeholder = _("myproject.mylab.ntua.gr")

app_name_validator   =  validators.RegexValidator(

                            DOMAIN_VALUE_REGEX,

                            _(astakos_messages.DOMAIN_VALUE_ERR),

                            'invalid')

app_name_help        =  _("""

        The Project's name should be in a domain format.

        The domain shouldn't neccessarily exist in the real

        world but is helpful to imply a structure.

        e.g.: myproject.mylab.ntua.gr or

        myservice.myteam.myorganization""")

app_name_widget      =  forms.TextInput(

                            attrs={'placeholder': app_name_placeholder})

app_home_label       =  "Homepage URL"

app_home_placeholder =  'myinstitution.org/myproject/'

app_home_help        =  _("""

        URL pointing at your project's site.

        e.g.: myinstitution.org/myproject/.

        Leave blank if there is no website.""")

app_home_widget      =  forms.TextInput(

                            attrs={'placeholder': app_home_placeholder})

app_desc_label       =  _("Description")

app_desc_help        =  _("""

        Please provide a short but descriptive abstract of your Project,

        so that anyone searching can quickly understand

        what this Project is about.""")

app_comment_label    =  _("Comments for review (private)")

app_comment_help     =  _("""

        Write down any comments you may have for the reviewer

        of this application (e.g. background and rationale to

        support your request).

        The comments are strictly for the review process

        and will not be published.""")

app_start_date_label =  _("Start date")

app_start_date_help  =  _("""

        Provide a date when your need your project to be created,

        and members to be able to join and get resources.

        This date is only a hint to help prioritize reviews.""")

app_end_date_label   =  _("Termination date")

app_end_date_help    =  _("""

        At this date, the project will be automatically terminated

        and its resource grants revoked from all members.

        Unless you know otherwise,

        it is best to start with a conservative estimation.

        You can always re-apply for an extension, if you need.""")

join_policy_label    =  _("Joining policy")

leave_policy_label   =  _("Leaving policy")

max_members_label    =  _("Maximum member count")

max_members_help     =  _("""

        Specify the maximum number of members this project may have,

        including the owner. Beyond this number, no new members

        may join the project and be granted the project resources.

        Unless you certainly for otherwise,

        it is best to start with a conservative limit.

        You can always request a raise when you need it.""")

join_policies = PROJECT_MEMBER_JOIN_POLICIES.iteritems()

leave_policies = PROJECT_MEMBER_LEAVE_POLICIES.iteritems()

class ProjectApplicationForm(forms.ModelForm):

    name = forms.CharField(

        label     = app_name_label,

        help_text = app_name_help,

        widget    = app_name_widget,

        validators = [app_name_validator])

    homepage = forms.URLField(

        label     = app_home_label,

        help_text = app_home_help,

        widget    = app_home_widget,

        required  = False)

    description = forms.CharField(

        label     = app_desc_label,

        help_text = app_desc_help,

        widget    = forms.Textarea,

        required  = False)

    comments = forms.CharField(

        label     = app_comment_label,

        help_text = app_comment_help,

        widget    = forms.Textarea,

        required  = False)

    start_date = forms.DateTimeField(

        label     = app_start_date_label,

        help_text = app_start_date_help,

        required  = False)

    end_date = forms.DateTimeField(

        label     = app_end_date_label,

        help_text = app_end_date_help)

    member_join_policy  = forms.TypedChoiceField(

        label     = join_policy_label,

        initial   = 2,

        coerce    = int,

        choices   = join_policies)