We modify access_stream_for_delete_or_update function to return
Subscription object also along with stream. This change will be
helpful in avoiding an extra query to get subscription object in
code for updating subscription role.
We add a new wildcard_mention_policy setting to handle wildcard
mentions in large streams, with a wide range of policies available to
organizations.
We set the default to the safe option for preventing accidental spam:
only stream administrators being able to use wildcard mentions in
large streams.
We previously used to to redirect to config error page with
a different URL. This commit renders config error in the same
URL where configuration error is encountered. This way when
conifguration error is fixed the user can refresh to continue
normally or go back to login page from the link provided to
choose any other backend auth.
Also moved those URLs to dev_urls.py so that they can be easily
accessed to work on styling etc.
In tests, removed some of the asserts checking status code to be 200
as the function `assert_in_success_response` does that check.
We raise MissingAuthenticationError now, which adds
`www_authenticate=session` header to the error response. This
stops modern web-browsers from displaying a login form everytime
a 401 response it sent to the client.
Fixes#16284.
Most of the work for this was done when we implemented correct
behavior for guest users, since they treat public streams like private
streams anyway.
The general method involves moving the messages to the new stream with
special care of UserMessage.
We delete UserMessages for subs who are losing access to the message.
For private streams with protected history, we also create UserMessage
elements for users who are not present in the old stream, since that's
important for those users to access the moved messages.
Django treats path("<name>") like re_path(r"(?P<name>[^/]+)") and
path("<path:name>") like re_path(r"(?P<name>.+)").
This is more readable and consistent than the mix of slightly
different regexes we had before, and fixes various bugs:
• The r'apps/(.*)$' regex was missing a start anchor ^, so it
incorrectly matched all URLs that included apps/ as a substring
anywhere.
• The r'accounts/login/(google)/$' regex was missing a start anchor ^,
so it incorrectly matched all URLs that ended with
accounts/login/google/.
• The type annotation of zerver.views.realm_export.delete_realm_export
takes export_id as an int, but it was previously passed as a string.
• The type annotation of zerver.views.users.avatar takes medium as a
bool, but it was previously passed as a string.
• The [0-9A-Za-z]+ pattern for uidb64 was missing the - and _
characters that can validly be part of a base64url encoded
string (although I think the id is actually a decimal integer here,
in which case only 012345ADEIMNOQTUYcgjkwxyz are present in its
base64url encoding).
Signed-off-by: Anders Kaseorg <anders@zulip.com>
There are three functional side effects:
• Correct an insignificant but mathematically offensive bias toward
repeated characters in generate_api_key introduced in commit
47b4283c4b4c70ecde4d3c8de871c90ee2506d87; its entropy is increased
from 190.52864 bits to 190.53428 bits.
• Use the base32 alphabet in confirmation.models.generate_key; its
entropy is reduced from 124.07820 bits to the documented 120 bits, but
now it uses 1 syscall instead of 24.
• Use the base32 alphabet in get_bigbluebutton_url; its entropy is
reduced from 51.69925 bits to 50 bits, but now it uses 1 syscall
instead of 10.
(The base32 alphabet is A-Z 2-7. We could probably replace all of
these with plain secrets.token_urlsafe, since I expect most callers
can handle the full urlsafe_b64 alphabet A-Z a-z 0-9 - _ without
problems.)
Signed-off-by: Anders Kaseorg <anders@zulip.com>
For web-public streams, clients can access full topic history
without being authenticated. They only need to additionally
send "streams:web-public" narrow with their request like all
the other web-public queries.
When user requests for a realm that doesn't exists, we raise
a InvalidSubdomainError.
This reduces our effort at repeatedly ensuring realm is valid
in request in web-public queries.
'user_groups' endpoints are currently under 'pending_endpoints' in
test_openapi.py (even after being documented except one), due to the
'user_group_id' and 'group_id' parameter name mismatch in the
url config and the view functions.
This commit includes 'path_only=True' for 'user_group_id' parameter in
views to avoid the failure of 'test_openapi_arguments', in
test_openapi.py, which excludes the path parameters. This is a prep
commit for renaming 'group_id' to 'user_group_id' in the documentation
and removing the 'user_groups' endpoints from 'pending_endpoints'.
The new Stream administrator role is allowed to manage a stream they
administer, including:
* Setting properties like name, description, privacy and post-policy.
* Removing subscribers
* Deactivating the stream
The access_stream_for_delete_or_update is modified and is used only
to get objects from database and further checks for administrative
rights is done by check_stream_access_for_delete_or_update.
We have also added a new exception class StreamAdministratorRequired.
Via API, users can now access messages which are in web-public
streams without any authentication.
If the user is not authenticated, we assume it is a web-public
query and add `streams:web-public` narrow if not already present
to the narrow. web-public streams are also directly accessible.
Any malformed narrow which is not allowed in a web-public query
results in a 400 or 401. See test_message_fetch for the allowed
queries.
These weren’t wrong since orjson.JSONDecodeError subclasses
json.JSONDecodeError which subclasses ValueError, but the more
specific ones express the intention more clearly.
(ujson raised ValueError directly, as did json in Python 2.)
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This adds 'user_id' to the simple success response for 'POST /users'
api endpoint, to make it convenient for API clients to get details
about users they just created. Appropriate changes have been made in
the docs and test_users.py.
Fixes#16072.
This redirect was never effective -- because of the
HostDomainMiddleware, all requests to invalid domains have their
actual results thrown away, and replaced by an "Invalid realm" 404.
These lines are nonetheless _covered_ by coverage, because they do
run; the redirect is simply ineffective. This can be seen by the test
that was added with them, in c8edbae21c, actually testing the contents
for the invalid realm wording, not the "find your accounts" wording.
The exception trace only goes from where the exception was thrown up
to where the `logging.exception` call is; any context as to where
_that_ was called from is lost, unless `stack_info` is passed as well.
Having the stack is particularly useful for Sentry exceptions, which
gain the full stack trace.
Add `stack_info=True` on all `logging.exception` calls with a
non-trivial stack; we omit `wsgi.py`. Adjusts tests to match.
This commit modifies the /streams endpoint so that the web-public
streams are included in the default list of streams that users
have access to.
This is part of PR #14638 that aims to allow guest users to
browse and subscribe themselves to web public streams.
Three reasons:
1. The sliding was disorienting.
2. The collapsing disallowed searching for other pages with Ctrl+F.
3. The collapsing mechanism wasn't accessible (not usable with the
keyboard / no ARIA tags).
Tweaked by tabbott to center the left sidebar on the selected page.
Part of #15948.
A few major themes here:
- We remove short_name from UserProfile
and add the appropriate migration.
- We remove short_name from various
cache-related lists of fields.
- We allow import tools to continue to
write short_name to their export files,
and then we simply ignore the field
at import time.
- We change functions like do_create_user,
create_user_profile, etc.
- We keep short_name in the /json/bots
API. (It actually gets turned into
an email.)
- We don't modify our LDAP code much
here.
When you post to /json/users, we no longer
require or look at the short_name parameter,
since we don't use it in any meaningful way.
An upcoming commit will eliminate it from the
database.
Log RealmAuditLog in do_set_realm_property and do_remove_realm_domain.
Tests for the changes are written in test_events because it will save
duplicate code for test_change_realm_property.
There is still some miscellaneous cleanup that
has to happen for things like analytics queries
and dead code in node tests, but this should
remove the main use of pointers in the backend.
(We will also still need to drop the DB field.)
This commit is first of few commita which aim to change all the
bugdown references to markdown. This commits rename the files,
file path mentions and change the imports.
Variables and other references to bugdown will be renamed in susequent
commits.
Due to authentication restrictions, a deployment may need to direct
traffic for mobile applications to an alternate uri to take advantage
alternate authentication mechansism. By default the standard realm URI
will be usedm but if overridden in the settings file, an alternate uri
can be substituted.
Now we are consistent about validating color/description.
Ideally we wouldn't need to validate the
`streams_raw` parameters multiple times per
request, but the outer function here changes
the error messages to explicitly reference
the "delete" and "add" request variables.
And for the situation where the user-supplied
parameters are correct, the performance penalty
for checking them twice is extremely negligible.
So it's probably fine for now to just make sure
we use the same validators in all the relevant
places.
There's probably some deeper refactor that we
can do to eliminate the whole `compose_views`
scheme. And it's also not entirely clear to
me that we really need to support the update
endpoint. But that's all out of the scope of
this commit.
Update the REQ check for profile_data in
update_user_backend by tweaking `check_profile_data`
to use `check_dict_only`.
Here is the relevant URL:
path('users/<int:user_id>', rest_dispatch,
{'GET': 'zerver.views.users.get_members_backend',
It would be nice to unify the validator
for these two views, but they are different:
update_user_backend
update_user_custom_profile_data
It's not completely clear to me why update_user_backend
seems to support a superset of the functionality
of `update_user_custom_profile_data`, but it has
this code to allow you to remove custom profile fields:
clean_profile_data = []
for entry in profile_data:
assert isinstance(entry["id"], int)
if entry["value"] is None or not entry["value"]:
field_id = entry["id"]
check_remove_custom_profile_field_value(target, field_id)
else:
clean_profile_data.append({
"id": entry["id"],
"value": entry["value"],
})
Whereas the other view is much simpler:
def update_user_custom_profile_data(
<snip>
) -> HttpResponse:
validate_user_custom_profile_data(user_profile.realm.id, data)
do_update_user_custom_profile_data_if_changed(user_profile, data)
# We need to call this explicitly otherwise constraints are not check
return json_success()
This tightens our checking of user-supplied data
for this endpoint:
path('users/me/profile_data', rest_dispatch,
{'PATCH': 'zerver.views.custom_profile_fields.update_user_custom_profile_data',
...
We now explicitly require the `value` field
to be present in the dicts being passed in
here, as part of `REQ`. There is no reason
that our current clients would be sending
extra fields here, and we would just ignore
them anyway, so we also move to using
check_dict_only.
Here is some relevant webapp code (see settings_account.js):
fields.push({id: field.id, value: user_ids});
update_user_custom_profile_fields(fields, channel.patch);
settings_ui.do_settings_change(method, "/json/users/me/profile_data",
{data: JSON.stringify([field])}, spinner_element);
The webapp code sends fields one at a time
as one-element arrays, which is strange, but
that is out of the scope of this change.
`/api/v1/fetch_api_key`'s response had a key `email` with the user's
delivery email. But its JSON counterpart `/json/fetch_api_key`, which
has a completely different implementation, did not return `email` in
its success response.
So to avoid confusion, the non-API endpoint, `/json/fetch_api_key`
response has been made identical with it's `/api` counterpart by
adding the `email` key. Also it is safe to send as the calling user
will only see their own email.
Currently, we use -1 as the Realm.message_retention_days value to retain
message forever unless specified at stream level for a particular stream,
that is, no policy set at the realm level. But this is incoherent with what
we use for Stream.message_retention_days where -1 means
> disable retention policy for this stream unconditionally
that can be confusing from an API standpoint.
So instead of trying some hack to reset the value to NULL or using some
other value like -2 for RETAIN_MESSAGE_FOREVER and use that for API. It is
much more intuitive to use a string like 'forever' that can be mapped to
RETAIN_MESSAGE_FOREVER at the backend. And this is similar to what we use
for streams settings as well.
In 5200598a31, we introduced a new
client capability that can be used to avoid unreasonable network
bandwidth consumed sending avatar URLs of long term idle users in
organizations with 10,000s members.
This commit enables this feature and adds support for it to the web
client.
With this implementation of the feature of the automatic theme
detection, we make the following changes in the backend, frontend and
documentation.
This replaces the previous night_mode boolean with an enum, with the
default value being to use the prefers-color-scheme feature of the
operating system to determine which theme to use.
Fixes: #14451.
Co-authored-by: @kPerikou <44238834+kPerikou@users.noreply.github.com>
We can now invite new users as realm owners. We restrict only
owners to invite new users as owners both for single invite
and multiuse invite link. Also, only owners can revoke or resend
owner invitations.
Old: a validator returns None on success and returns an error string
on error.
New: a validator returns the validated value on success and raises
ValidationError on error.
This allows mypy to catch mismatches between the annotated type of a
REQ parameter and the type that the validator actually validates.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Rename the validator to check_union, to conform
more to Python typing nomenclature.
And we rename one of the test helpers to the
simpler `check_types`. (The test helper
was using "variable" in the "var" sense.)
The non-search code path here was simulating the response and escaping
logic from get_search_fields by duplicating what it would do with an
empty set of highlight locations.
We can produce much more readable code by just passing an empty list
of locations in this case.
This adds a new client_capability that clients such as the mobile apps
can use to avoid unreasonable network bandwidth consumed sending
avatar URLs in organizations with 10,000s of users.
Clients don't strictly need this data, as they can always use the
/avatar/{user_id} endpoint to fetch the avatar if desired.
This will be more efficient especially for realms with
10,000+ users because the avatar URLs would increase the
payload size significantly and cost us more bandwidth.
Fixes#15287.
This commit adds backend support for setting message_retention_days
while creating streams and updating it for an existing stream. We only
allow organization owners to set/update it for a stream.
'message_retention_days' field for a stream existed previously also, but
there was no way to set it while creating streams or update it for an
exisiting streams using any endpoint.
The most import change here is the one in maybe_send_to_registration
codepath, as the insufficient validation there could lead to fetching
an expired PreregistrationUser that was invited as an administrator
admin even years ago, leading to this registration ending up in the
new user being a realm administrator.
Combined with the buggy migration in
0198_preregistrationuser_invited_as.py, this led to users incorrectly
joining as organizations administrators by accident. But even without
that bug, this issue could have allowed a user who was invited as an
administrator but then had that invitation expire and then joined via
social authentication incorrectly join as an organization administrator.
The second change is in ConfirmationEmailWorker, where this wasn't a
security problem, but if the server was stopped for long enough, with
some invites to send out email for in the queue, then after starting it
up again, the queue worker would send out emails for invites that
had already expired.
Google has removed the Google Hangouts brand, thus we are removing
them as video chat provider option.
This commit removes Google Hangouts integration and make a migration
that sets all realms that are using Hangouts as their video chat
provider to the default, jitsi.
With changes by tabbott to improve the overall video call documentation.
Fixes: #15298.
Fixes#14828.
Giving the /subdomain/<token>/ url there could feel buggy if the user
ended up using the token in the desktop app, and then tried clicking the
"continue in browser" link - which had the same token that would now be
expired. It's sufficient to simply link to /login/ instead.
Fixes#15285
This event will be used more now for guest users when moving
topic between streams (See #15277). So, instead of deleting
messages in the topic as part of different events which is
very slow and a bad UX, we now handle the messages to delete in
bulk which is a much better UX.
This is designed to have no user-facing change unless the client
declares bulk_message_deletion in its client_capabilities.
Clients that do so will receive a single bulk event for bulk deletions
of messages within a single conversation (topic or PM thread).
Backend implementation of #15285.
This commits adds restriction on admins to set message retention policy.
We now only allow only organization owners to set message retention
policy.
Dropdown for changing retention policy is disabled in UI for admins also.
Use read-only types (List ↦ Sequence, Dict ↦ Mapping, Set ↦
AbstractSet) to guard against accidental mutation of the default
value.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
There seems to have been a confusion between two different uses of the
word “optional”:
• An optional parameter may be omitted and replaced with a default
value.
• An Optional type has None as a possible value.
Sometimes an optional parameter has a default value of None, or None
is otherwise a meaningful value to provide, in which case it makes
sense for the optional parameter to have an Optional type. But in
other cases, optional parameters should not have Optional type. Fix
them.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Fixes#2665.
Regenerated by tabbott with `lint --fix` after a rebase and change in
parameters.
Note from tabbott: In a few cases, this converts technical debt in the
form of unsorted imports into different technical debt in the form of
our largest files having very long, ugly import sequences at the
start. I expect this change will increase pressure for us to split
those files, which isn't a bad thing.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Automatically generated by the following script, based on the output
of lint with flake8-comma:
import re
import sys
last_filename = None
last_row = None
lines = []
for msg in sys.stdin:
m = re.match(
r"\x1b\[35mflake8 \|\x1b\[0m \x1b\[1;31m(.+):(\d+):(\d+): (\w+)", msg
)
if m:
filename, row_str, col_str, err = m.groups()
row, col = int(row_str), int(col_str)
if filename == last_filename:
assert last_row != row
else:
if last_filename is not None:
with open(last_filename, "w") as f:
f.writelines(lines)
with open(filename) as f:
lines = f.readlines()
last_filename = filename
last_row = row
line = lines[row - 1]
if err in ["C812", "C815"]:
lines[row - 1] = line[: col - 1] + "," + line[col - 1 :]
elif err in ["C819"]:
assert line[col - 2] == ","
lines[row - 1] = line[: col - 2] + line[col - 1 :].lstrip(" ")
if last_filename is not None:
with open(last_filename, "w") as f:
f.writelines(lines)
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
This commit adds three `.pysa` model files: `false_positives.pysa`
for ruling out false positive flows with `Sanitize` annotations,
`req_lib.pysa` for educating pysa about Zulip's `REQ()` pattern for
extracting user input, and `redirects.pysa` for capturing the risk
of open redirects within Zulip code. Additionally, this commit
introduces `mark_sanitized`, an identity function which can be used
to selectively clear taint in cases where `Sanitize` models will not
work. This commit also puts `mark_sanitized` to work removing known
false postive flows.
This commit adds 'add_query_to_redirect_url' to one additional
function which had not yet been written when
'add_query_to_redirect_url' was introduced. This helper centralizes
URL manipulation for redirects, making it easier to add Pysa
sanitization in subsequent commits.
This new endpoint returns a 'user' dictionary which, as of now,
contains a single key 'is_subscribed' with a boolean value that
represents whether the user with the given 'user_id' is subscribed
to the stream with the given 'stream_id'.
Fixes#14966.
The only clients that should use the typing
indicators endpoint are our internal clients,
and they should send a JSON-formatted list
of user_ids.
We now enforce this, which removes some
complexity surrounding legacy ways of sending
users, such as emails and comma-delimited
strings of user_ids.
There may be a very tiny number of mobile
clients that still use the old emails API.
This won't have any user-facing effect on
the mobile users themselves, but if you type
a message to your friend on an old mobile
app, the friend will no longer see typing
indicators.
Also, the mobile team may see some errors
in their Sentry logs from the server rejecting
posts from the old mobile clients.
The error messages we report here are a bit
more generic, since we now just use REQ
to do validation with this code:
validator=check_list(check_int)
This also allows us to remove a test hack
related to the API documentation. (We changed
the docs to reflect the modern API in an
earlier commit, but the tests couldn't be
fixed while we still had the more complex
semantics for the "to" parameter.)
This commit adds some basic checks while adding or removing
realm owner status of a user and adds code to change owner
status of a user using update_user_backend.
This also adds restriction on removing owner status of the
last owner of realm. This restriction was previously on
revoking admin status, but as we have added a more privileged
role of realm owner, we now have this restriction on owner
instead of admin.
We need to apply that restriction both in the role change code path
and the deactivate code path.
set(redirect_host) is a set of characters, so the only non-relative
redirects being allowed were to certain one-character hostnames, which
certainly isn’t what was intended.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This implementation overrides some of PSA's internal backend
functions to handle `state` value with redis as the standard
way doesn't work because of apple sending required details
in the form of POST request.
Includes a mixin test class that'll be useful for testing
Native auth flow.
Thanks to Mateusz Mandera for the idea of using redis and
other important work on this.
Documentation rewritten by tabbott.
Co-authored-by: Mateusz Mandera <mateusz.mandera@zulip.com>
This was implemented in 2012 to avoid showing a loading indicator for
fetching messages for users with no message history. However, the
Zulip onboarding UI always creates some message history, and fetching
history is fast, so this is likely clutter more than a useful
optimization.
We're migrating to using the cleaner zulip.com domain, which involves
changing all of our links from ReadTheDocs and other places to point
to the cleaner URL.
Since owners have the highest privilege level, it made little sense to
sandwich them between administrators and guests.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This commit removes short_name and client_id fields from the user
objects returned by get_profile_backend because neither of them
had a purpose.
* short_name hasn't been present anywhere else in the Zulip API for
several years, and isn't set through any coherent algorithm.
* client_id was a forgotten 2013-era predecessor to the queue_id field
returned by the register_event_queue process.
The combination of these changes gets us close to having `get_profile`
have the exact same format as other endpoints fetching a user object.
This commit changes get_profile_backend to be based on format_user_row
such that it's a superset of the fields for our other endpoints for
getting data on a user.
To be clear, this does not removes any of the exisiting fields, that
were returned by this endpoint.
This change adds some fields to the User object returned by the
endpoint. API docs are updated accordingly for the added fields.
Calling jwt.decode without an algorithms list raises a
DeprecationWarning. This is for protecting against
symmetric/asymmetric key confusion attacks.
This is a backwards-incompatible configuration change.
Fixes#15207.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Generated by pyupgrade --py36-plus --keep-percent-format, but with the
NamedTuple changes reverted (see commit
ba7906a3c6, #15132).
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This commit extracts removing_someone_else logic to the function
'check_if_removing_someone_else' for better readability.
This is a follow up to 2187c84.
Option to disable breadcrumb messages were given in both message edit
form and topic edit stream popover.
User now has the option to select which stream to send the notification
of stream edit of a topic via checkboxes in the UI.
This reimplements our Zoom video call integration to use an OAuth
application. In addition to providing a cleaner setup experience,
especially on zulipchat.com where the server administrators can have
done the app registration already, it also fixes the limitation of the
previous integration that it could only have one call active at a time
when set up with typical Zoom API keys.
Fixes#11672.
Co-authored-by: Marco Burstein <marco@marco.how>
Co-authored-by: Tim Abbott <tabbott@zulipchat.com>
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
We change do_create_user and create_user to accept
role as a parameter instead of 'is_realm_admin' and 'is_guest'.
These changes are done to minimize data conversions between
role and boolean fields.
This commit modifies the backend to accept user ids when subscribing
users to streams.
It also migrates all existing tests to use this API, aside from a
small set of tests for the legacy API.
This commit changes the update user API endpoint to accept role
as parameter instead of the bool parameters is_guest and is_admin.
User role dropdown in user info modal is also modified to use
"dropdown_options_widget".
Modified by tabbott to document the API change.
If the key paramenter on POST isn't correct we won't be
able to find the confirmation object, which will lead to
an exception. To deal with it more gracefully, we are
catching the exception and redirecting to the
confirmation_link_expired_error page.
If a user receives more than one invite to join a
realm, after that user registers, all the remaining
invitations should be revoked, preventing them to be
listed in active invitations on admin panel.
To do this, we added a new prereg_user status,
STATUS_REVOKED.
We also added a confirmation_link_expired_error page
in case the user tries click on a revoked invitaion.
This page has a link to login page.
Fixes: #12629
Co-authored-by: Arunika <arunikayadav42@gmail.com>
On invitations panel, invites were being removed when
the user clicked on invitation's link. Now we only remove
it when the user completes registration.
Fixes: #12281
mock is just a backport of the standard library’s unittest.mock now.
The SAMLAuthBackendTest change is needed because
MagicMock.call_args.args wasn’t introduced until Python
3.8 (https://bugs.python.org/issue21269).
The PROVISION_VERSION bump is skipped because mock is still an
indirect dev requirement via moto.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This commit merges do_change_is_admin and do_change_is_guest to a
single function do_change_user_role which will be used for changing
role of users.
do_change_is_api_super_user is added as a separate function for
changing is_api_super_user field of UserProfile.
The query to fetch the latest user activity was missing an
`.order_by('last_visit')`. This meant that the results were being
ordered by the `id`, which resulted in us getting `update_message_flags`
action performed on the client that the user installed last, instead of
being client agnostic and fetching the "global" last
`update_message_flags` action performed by the user.
These changes should be included in bd9b74436c,
as it makes sure that Zulip limited plan realm won't be able to change the
`message_retention_days` setting.
The pointer doesn't get updated when a user is only reading messages in
narrowed views. But, we use the pointer position to determine the
furthest read time, which causes the bankruptcy banner to show up even
for users who have been actively reading and sending messages.
This commit switches to using the time of the last update_message_flags
activity by a user to determine the time of last activity.
Since production testing of `message_retention_days` is finished, we can
enable this feature in the organization settings page. We already had this
setting in frontend but it was bit rotten and not rendered in templates.
Here we replaced our past text-input based setting with a
dropdown-with-text-input setting approach which is more consistent with our
existing UI.
Along with frontend changes, we also incorporated a backend change to
handle making retention period forever. This change introduces a new
convertor `to_positive_or_allowed_int` which only allows positive integers
and an allowed value for settings like `message_retention_days` which can
be a positive integer or has the value `Realm.RETAIN_MESSAGE_FOREVER` when
we change the setting to retain message forever.
This change made `to_not_negative_int_or_none` redundant so removed it as
well.
Fixes: #14854