the connector schemas are shared between authn, auth and bridges,
the difference is that authn and authz configs are unions like:
[
{mongo_type = rs,
...
}
{another backend config}
]
however the brdige types are maps like, for example:
mongodb_rs.$name {
mongo_type = rs
...
}
in which case, the mongo_type is not required.
in order to keep the schema static as much as possible,
this field is chanegd to 'required => false' with a default value.
However, for authn and authz, the union selector will still raise
exception if the there is no type provided.
This fixes https://emqx.atlassian.net/browse/EMQX-8648. The issue
described in `EMQX-8648` is that when deleting a non-existing bridge the
server gives a success response. See below:
```
curl --head -u admin:public2 -X 'DELETE' 'http://localhost:18083/api/v5/bridges/webhook:i_do_not_exist'
HTTP/1.1 204 No Content
date: Tue, 03 Jan 2023 16:59:01 GMT
server: Cowboy
```
After the fix, deleting a non existing bridge will give the following
response:
```
HTTP/1.1 404 Not Found
content-length: 49
content-type: application/json
date: Thu, 05 Jan 2023 12:40:35 GMT
server: Cowboy
```
Closes: EMQX-8648
This makes the buffer/resource workers always use `replayq` for
queuing, along with collecting multiple requests in a single call.
This is done to avoid long message queues for the buffer workers and
rely on `replayq`'s capabilities of offloading to disk and detecting
overflow.
Also, this deprecates the `enable_batch` and `enable_queue` resource
creation options, as: i) queuing is now always enables; ii) batch_size
> 1 <=> batch_enabled. The corresponding metric
`dropped.queue_not_enabled` is dropped, along with `batching`. The
batching is too ephemeral, especially considering a default batch time
of 20 ms, and is not shown in the dashboard, so it was removed.
To avoid confusion for the users as to what persistence guarantees we
offer when buffering bridges/resources, we will always enable offload
mode for `replayq`. With this, when the buffer size is above the max
segment size, it'll flush the queue to disk, but on recovery after a
restart it'll clean the existing segments rather than resuming from
them.