OpenSlides/openslides/core/views.py
FinnStutzenstein 5aef823807 Major cache rewrite:
- Removed the restricted data cache (it wasn't used since OS 3.0)
- unify functions for restricted and full data: Just one function, which
  accteps an optional user_id: If it is None, full data is returned, and
  with a user id given, the restricted data
- More atomic access to redis, especially for:
- Check for data-existance in redis and do an auto-ensure-cache.
- Speedup through hashing of scripts and redis' script cache.
- Save schema version into the redis cache and rebuild, if the version
  changed

Client changes:
- Simplified the ConstantsService
- Fixed bug, when receiving an autoupdate with all_data=True from the
  Server
2019-08-08 08:35:02 +02:00

623 lines
21 KiB
Python

import datetime
import os
from collections import defaultdict
from typing import Any, Dict
from asgiref.sync import async_to_sync
from django.conf import settings
from django.contrib.staticfiles import finders
from django.contrib.staticfiles.views import serve
from django.db.models import F
from django.http import Http404, HttpResponse
from django.utils.timezone import now
from django.views import static
from django.views.generic.base import View
from openslides.utils.utils import split_element_id
from .. import __license__ as license, __url__ as url, __version__ as version
from ..users.models import User
from ..utils import views as utils_views
from ..utils.arguments import arguments
from ..utils.auth import GROUP_ADMIN_PK, anonymous_is_enabled, has_perm, in_some_groups
from ..utils.autoupdate import inform_changed_data
from ..utils.cache import element_cache
from ..utils.plugins import (
get_plugin_description,
get_plugin_license,
get_plugin_url,
get_plugin_verbose_name,
get_plugin_version,
)
from ..utils.rest_api import (
GenericViewSet,
ListModelMixin,
ModelViewSet,
Response,
RetrieveModelMixin,
ValidationError,
detail_route,
)
from .access_permissions import (
ConfigAccessPermissions,
CountdownAccessPermissions,
ProjectionDefaultAccessPermissions,
ProjectorAccessPermissions,
ProjectorMessageAccessPermissions,
TagAccessPermissions,
)
from .config import config
from .exceptions import ConfigError, ConfigNotFound
from .models import (
ConfigStore,
Countdown,
History,
HistoryData,
ProjectionDefault,
Projector,
ProjectorMessage,
Tag,
)
from .serializers import elements_array_validator, elements_validator
# Special Django views
class IndexView(View):
"""
The primary view for the OpenSlides client. Serves static files. If a file
does not exist or a directory is requested, the index.html is delivered instead.
"""
cache: Dict[str, str] = {}
"""
Saves the path to the index.html.
May be extended later to cache every template.
"""
def __init__(self, *args: Any, **kwargs: Any) -> None:
super().__init__(*args, **kwargs)
no_caching = arguments.get("no_template_caching", False)
if "index" not in self.cache or no_caching:
self.cache["index"] = finders.find("index.html")
self.index_document_root, self.index_path = os.path.split(self.cache["index"])
def get(self, request, path, **kwargs) -> HttpResponse:
"""
Tries to serve the requested file. If it is not found or a directory is
requested, the index.html is delivered.
"""
try:
response = serve(request, path, insecure=True, **kwargs)
except Http404:
response = static.serve(
request,
self.index_path,
document_root=self.index_document_root,
**kwargs,
)
return response
# Viewsets for the REST API
class ProjectorViewSet(ModelViewSet):
"""
API endpoint for the projector slide info.
There are the following views: See strings in check_view_permissions().
"""
access_permissions = ProjectorAccessPermissions()
queryset = Projector.objects.all()
def check_view_permissions(self):
"""
Returns True if the user has required permissions.
"""
if self.action in ("list", "retrieve"):
result = self.get_access_permissions().check_permissions(self.request.user)
elif self.action == "metadata":
result = has_perm(self.request.user, "core.can_see_projector")
elif self.action in (
"create",
"update",
"partial_update",
"destroy",
"control_view",
"set_scroll",
"set_projectiondefault",
"project",
):
result = has_perm(self.request.user, "core.can_see_projector") and has_perm(
self.request.user, "core.can_manage_projector"
)
else:
result = False
return result
def perform_create(self, serializer):
projector = serializer.save()
projector.elements = [{"name": "core/clock", "stable": True}]
projector.save()
def destroy(self, *args, **kwargs):
"""
REST API operation for DELETE requests.
Assigns all ProjectionDefault objects from this projector to the
first projector found.
"""
if len(Projector.objects.all()) <= 1:
raise ValidationError({"detail": "You can't delete the last projector."})
projector_instance = self.get_object()
new_projector_id = (
Projector.objects.exclude(pk=projector_instance.pk).first().pk
)
for projection_default in ProjectionDefault.objects.all():
if projection_default.projector.id == projector_instance.id:
projection_default.projector_id = new_projector_id
projection_default.save()
return super(ProjectorViewSet, self).destroy(*args, **kwargs)
@detail_route(methods=["post"])
def project(self, request, pk):
"""
Sets the `elements` and `elements_preview` and adds one item to the
`elements_history`.
`request.data` can have three arguments: `append_to_history`, `elements`
and `preview`. Non of them is required.
`append_to_history` adds one element to the end of the history_elements.
`elements` and `preview` preplaces the coresponding fields in the
database.
If `delete_last_history_element` is True, the last element is deleted.
Note: You cannot give `append_to_history` and `delete_last_history_element`
at the same time.
If `reset_scroll` is True, the scoll of the projector will reset.
"""
projector = self.get_object()
elements = request.data.get("elements")
preview = request.data.get("preview")
history_element = request.data.get("append_to_history")
delete_last_history_element = request.data.get(
"delete_last_history_element", False
)
reset_scroll = request.data.get("reset_scroll", False)
if elements is not None:
elements_validator(elements)
projector.elements = elements
if preview is not None:
elements_validator(preview)
projector.elements_preview = preview
elements_history = None
if history_element is not None and delete_last_history_element is False:
elements_history = projector.elements_history + [history_element]
if history_element is None and delete_last_history_element is True:
elements_history = projector.elements_history[:-1]
if elements_history is not None:
elements_array_validator(elements_history)
projector.elements_history = elements_history
if reset_scroll:
projector.scroll = 0
projector.save()
return Response()
@detail_route(methods=["post"])
def control_view(self, request, pk):
"""
REST API operation to control the projector view, i. e. scale and
scroll the projector.
It expects a POST request to
/rest/core/projector/<pk>/control_view/ with a dictionary with an
action ('scale' or 'scroll') and a direction ('up', 'down' or
'reset'). An optional 'step' can be given to control the amount
of scrolling and scaling. The default is 1.
Example:
{
"action": "scale",
"direction": "up"
}
"""
if not isinstance(request.data, dict):
raise ValidationError({"detail": "Data must be a dictionary."})
if request.data.get("action") not in ("scale", "scroll") or request.data.get(
"direction"
) not in ("up", "down", "reset"):
raise ValidationError(
{
"detail": "Data must be a dictionary with an action ('scale' or 'scroll') "
"and a direction ('up', 'down' or 'reset')."
}
)
projector_instance = self.get_object()
step = request.data.get("step", 1)
if step < 1:
step = 1
if request.data["action"] == "scale":
if request.data["direction"] == "up":
projector_instance.scale = F("scale") + step
elif request.data["direction"] == "down":
projector_instance.scale = F("scale") - step
else:
# request.data['direction'] == 'reset'
projector_instance.scale = 0
else:
# request.data['action'] == 'scroll'
if request.data["direction"] == "up":
projector_instance.scroll = F("scroll") + step
elif request.data["direction"] == "down":
projector_instance.scroll = F("scroll") - step
else:
# request.data['direction'] == 'reset'
projector_instance.scroll = 0
projector_instance.save(skip_autoupdate=True)
projector_instance.refresh_from_db()
inform_changed_data(projector_instance)
return Response()
@detail_route(methods=["post"])
def set_scroll(self, request, pk):
"""
REST API operation to scroll the projector.
It expects a POST request to
/rest/core/projector/<pk>/set_scroll/ with a new value for scroll.
"""
if not isinstance(request.data, int):
raise ValidationError({"detail": "Data must be an int."})
projector_instance = self.get_object()
projector_instance.scroll = request.data
projector_instance.save()
message = f"Setting scroll to {request.data} was successful."
return Response({"detail": message})
class ProjectionDefaultViewSet(ListModelMixin, RetrieveModelMixin, GenericViewSet):
"""
API endpoint for projection defaults.
There are the following views: list, and retrieve. Assigning projection defaults
to projectors can be done by updating the projector.
"""
access_permissions = ProjectionDefaultAccessPermissions()
queryset = ProjectionDefault.objects.all()
def check_view_permissions(self):
"""
Returns True if the user has required permissions.
"""
if self.action in ("list", "retrieve"):
result = self.get_access_permissions().check_permissions(self.request.user)
else:
result = False
return result
class TagViewSet(ModelViewSet):
"""
API endpoint for tags.
There are the following views: metadata, list, retrieve, create,
partial_update, update and destroy.
"""
access_permissions = TagAccessPermissions()
queryset = Tag.objects.all()
def check_view_permissions(self):
"""
Returns True if the user has required permissions.
"""
if self.action in ("list", "retrieve"):
result = self.get_access_permissions().check_permissions(self.request.user)
elif self.action == "metadata":
# Every authenticated user can see the metadata.
# Anonymous users can do so if they are enabled.
result = self.request.user.is_authenticated or anonymous_is_enabled()
elif self.action in ("create", "partial_update", "update", "destroy"):
result = has_perm(self.request.user, "core.can_manage_tags")
else:
result = False
return result
class ConfigViewSet(ModelViewSet):
"""
API endpoint for the config.
There are the following views: metadata, list, retrieve, update and
partial_update.
"""
access_permissions = ConfigAccessPermissions()
queryset = ConfigStore.objects.all()
def check_view_permissions(self):
"""
Returns True if the user has required permissions.
"""
if self.action in ("list", "retrieve"):
result = self.get_access_permissions().check_permissions(self.request.user)
elif self.action == "metadata":
# Every authenticated user can see the metadata and list or
# retrieve the config. Anonymous users can do so if they are
# enabled.
result = self.request.user.is_authenticated or anonymous_is_enabled()
elif self.action in ("partial_update", "update"):
# The user needs 'core.can_manage_logos_and_fonts' for all config values
# starting with 'logo' and 'font'. For all other config values th euser needs
# the default permissions 'core.can_manage_config'.
pk = self.kwargs["pk"]
if pk.startswith("logo") or pk.startswith("font"):
result = has_perm(self.request.user, "core.can_manage_logos_and_fonts")
else:
result = has_perm(self.request.user, "core.can_manage_config")
else:
result = False
return result
def update(self, request, *args, **kwargs):
"""
Updates a config variable. Only managers can do this.
Example: {"value": 42}
"""
key = kwargs["pk"]
value = request.data.get("value")
if value is None:
raise ValidationError({"detail": "Invalid input. Config value is missing."})
# Validate and change value.
try:
config[key] = value
except ConfigNotFound:
raise Http404
except ConfigError as err:
raise ValidationError({"detail": str(err)})
# Return response.
return Response({"key": key, "value": value})
class ProjectorMessageViewSet(ModelViewSet):
"""
API endpoint for messages.
There are the following views: list, retrieve, create, update,
partial_update and destroy.
"""
access_permissions = ProjectorMessageAccessPermissions()
queryset = ProjectorMessage.objects.all()
def check_view_permissions(self):
"""
Returns True if the user has required permissions.
"""
if self.action in ("list", "retrieve"):
result = self.get_access_permissions().check_permissions(self.request.user)
elif self.action in ("create", "partial_update", "update", "destroy"):
result = has_perm(self.request.user, "core.can_manage_projector")
else:
result = False
return result
class CountdownViewSet(ModelViewSet):
"""
API endpoint for Countdown.
There are the following views: list, retrieve, create, update,
partial_update and destroy.
"""
access_permissions = CountdownAccessPermissions()
queryset = Countdown.objects.all()
def check_view_permissions(self):
"""
Returns True if the user has required permissions.
"""
if self.action in ("list", "retrieve"):
result = self.get_access_permissions().check_permissions(self.request.user)
elif self.action in ("create", "partial_update", "update", "destroy"):
result = has_perm(self.request.user, "core.can_manage_projector")
else:
result = False
return result
# Special API views
class ServerTime(utils_views.APIView):
"""
Returns the server time as UNIX timestamp.
"""
http_method_names = ["get"]
def get_context_data(self, **context):
return now().timestamp()
class VersionView(utils_views.APIView):
"""
Returns a dictionary with the OpenSlides version and the version of all
plugins.
"""
http_method_names = ["get"]
def get_context_data(self, **context):
result: Dict[str, Any] = {
"openslides_version": version,
"openslides_license": license,
"openslides_url": url,
"plugins": [],
"no_name_yet_users": User.objects.filter(last_login__isnull=False).count(),
}
# Versions of plugins.
for plugin in settings.INSTALLED_PLUGINS:
result["plugins"].append(
{
"verbose_name": get_plugin_verbose_name(plugin),
"description": get_plugin_description(plugin),
"version": get_plugin_version(plugin),
"license": get_plugin_license(plugin),
"url": get_plugin_url(plugin),
}
)
return result
class HistoryInformationView(utils_views.APIView):
"""
View to retrieve information about OpenSlides history.
Use GET to search history information. The query parameter 'type' determines
the type of your search:
Examples:
/?type=element&value=motions%2Fmotion%3A42 if your search for motion 42
Use DELETE to clear the history.
"""
http_method_names = ["get", "delete"]
def get_context_data(self, **context):
"""
Checks permission and parses query parameters.
"""
if not has_perm(self.request.user, "core.can_see_history"):
self.permission_denied(self.request)
type = self.request.query_params.get("type")
value = self.request.query_params.get("value")
if type not in ("element"):
raise ValidationError(
{"detail": "Invalid input. Type should be 'element' or 'text'."}
)
# We currently just support searching by element id.
data = self.get_data_element_search(value)
return data
def get_data_element_search(self, value):
"""
Retrieves history information for element search.
"""
data = []
for instance in History.objects.filter(element_id=value).order_by("-now"):
if instance.information:
data.append(
{
"element_id": instance.element_id,
"timestamp": instance.now.timestamp(),
"information": instance.information,
"user_id": instance.user.pk if instance.user else None,
}
)
return data
def delete(self, request, *args, **kwargs):
"""
Deletes and rebuilds the history.
"""
# Check permission
if not in_some_groups(request.user.pk or 0, [GROUP_ADMIN_PK]):
self.permission_denied(request)
# Delete history data and history (via CASCADE)
HistoryData.objects.all().delete()
# Rebuild history.
History.objects.build_history()
return Response({"detail": "History was deleted and rebuild successfully."})
class HistoryDataView(utils_views.APIView):
"""
View to retrieve the history data of OpenSlides.
Use query paramter timestamp (UNIX timestamp) to get all elements from begin
until (including) this timestamp.
"""
http_method_names = ["get"]
def get_context_data(self, **context):
"""
Checks if user is in admin group. If yes, all history data until
(including) timestamp are collected to build a valid dataset for the client.
"""
if not in_some_groups(self.request.user.pk or 0, [GROUP_ADMIN_PK]):
self.permission_denied(self.request)
try:
timestamp = int(self.request.query_params.get("timestamp", 0))
except ValueError:
raise ValidationError(
{"detail": "Invalid input. Timestamp should be an integer."}
)
queryset = History.objects.select_related("full_data")
if timestamp:
queryset = queryset.filter(
now__lte=datetime.datetime.fromtimestamp(timestamp)
)
# collection <--> id <--> full_data
dataset: Dict[str, Dict[int, Any]] = defaultdict(dict)
for instance in queryset:
collection, id = split_element_id(instance.element_id)
full_data = instance.full_data.full_data
if full_data:
dataset[collection][id] = full_data
elif id in dataset[collection]:
del dataset[collection][id]
# Ensure, that newer configs than the requested timepoint are also
# included, so the client is happy and doesn't miss any config variables.
all_current_config_keys = set(config.config_variables.keys())
all_old_config_keys = set(
map(lambda config: config["key"], dataset["core/config"].values())
)
missing_keys = all_current_config_keys - all_old_config_keys
if missing_keys:
config_full_data = async_to_sync(element_cache.get_collection_data)(
"core/config"
)
key_to_id = config.get_key_to_id()
for key in missing_keys:
id = key_to_id[key]
dataset["core/config"][id] = config_full_data[id]
return {
collection: list(dataset[collection].values())
for collection in dataset.keys()
}