forked-synapse/docs/modules/presence_router_callbacks.md

Ignoring revisions in .git-blame-ignore-revs. Click here to bypass and see the normal blame view.

91 lines
3.2 KiB
Markdown
Raw Normal View History

# Presence router callbacks
Presence router callbacks allow module developers to specify additional users (local or remote)
to receive certain presence updates from local users. Presence router callbacks can be
registered using the module API's `register_presence_router_callbacks` method.
## Callbacks
The available presence router callbacks are:
### `get_users_for_states`
```python
async def get_users_for_states(
state_updates: Iterable["synapse.api.UserPresenceState"],
) -> Dict[str, Set["synapse.api.UserPresenceState"]]
```
**Requires** `get_interested_users` to also be registered
Called when processing updates to the presence state of one or more users. This callback can
be used to instruct the server to forward that presence state to specific users. The module
must return a dictionary that maps from Matrix user IDs (which can be local or remote) to the
`UserPresenceState` changes that they should be forwarded.
Synapse will then attempt to send the specified presence updates to each user when possible.
### `get_interested_users`
```python
async def get_interested_users(
user_id: str
) -> Union[Set[str], "synapse.module_api.PRESENCE_ALL_USERS"]
```
**Requires** `get_users_for_states` to also be registered
Called when determining which users someone should be able to see the presence state of. This
callback should return complementary results to `get_users_for_state` or the presence information
may not be properly forwarded.
The callback is given the Matrix user ID for a local user that is requesting presence data and
should return the Matrix user IDs of the users whose presence state they are allowed to
query. The returned users can be local or remote.
Alternatively the callback can return `synapse.module_api.PRESENCE_ALL_USERS`
to indicate that the user should receive updates from all known users.
## Example
The example below is a module that implements both presence router callbacks, and ensures
that `@alice:example.org` receives all presence updates from `@bob:example.com` and
`@charlie:somewhere.org`, regardless of whether Alice shares a room with any of them.
```python
from typing import Dict, Iterable, Set, Union
from synapse.module_api import ModuleApi
class CustomPresenceRouter:
def __init__(self, config: dict, api: ModuleApi):
self.api = api
self.api.register_presence_router_callbacks(
get_users_for_states=self.get_users_for_states,
get_interested_users=self.get_interested_users,
)
async def get_users_for_states(
self,
state_updates: Iterable["synapse.api.UserPresenceState"],
) -> Dict[str, Set["synapse.api.UserPresenceState"]]:
res = {}
for update in state_updates:
if (
update.user_id == "@bob:example.com"
or update.user_id == "@charlie:somewhere.org"
):
res.setdefault("@alice:example.com", set()).add(update)
return res
async def get_interested_users(
self,
user_id: str,
) -> Union[Set[str], "synapse.module_api.PRESENCE_ALL_USERS"]:
if user_id == "@alice:example.com":
return {"@bob:example.com", "@charlie:somewhere.org"}
return set()
```