Hi Miao,
On Thu, Apr 23, 2020 at 2:17 PM Miao-chen Chou <mcchou@xxxxxxxxxxxx> wrote:
>
> This patch proposes an Advertisement Monitoring API for an application to
> register a job of monitoring ADV reports with content filter and RSSI
> thresholds.
> ---
>
> Changes in v3:
> - Introduce SupportedFeatures to reflect the features based on
> controller's capabilities.
> - Modify SupportedMonitorTypes to list available types of monitors.
>
> Changes in v2:
> - Rename the interfaces and functions.
> - Adopt the object manager mechanism so that a client can expose
> multiple monitor objects and expect to get notified on whether the
> monitor has been activated or not.
> - Change the contract of DeviceFound so that it is called to indicate
> the starting point of monitoring on a device instead of reporting every
> ADV. In other words, the client is expected to monitor corresponding
> device events.
>
> doc/advertisement-monitor-api.txt | 134 ++++++++++++++++++++++++++++++
> 1 file changed, 134 insertions(+)
> create mode 100644 doc/advertisement-monitor-api.txt
>
> diff --git a/doc/advertisement-monitor-api.txt b/doc/advertisement-monitor-api.txt
> new file mode 100644
> index 000000000..b8b01536a
> --- /dev/null
> +++ b/doc/advertisement-monitor-api.txt
> @@ -0,0 +1,134 @@
> +BlueZ D-Bus Advertisement Monitor API Description
> +*************************************************
> +
> +This API allows an client to specify a job of monitoring advertisements by
> +registering the root of hierarchy and then exposing advertisement monitors
> +under the root with filtering conditions, thresholds of RSSI and timers
> +of RSSI thresholds.
> +
> +Once a monitoring job is activated by BlueZ, the client can expect to get
> +notified on the targeted advertisements no matter if there is an ongoing
> +discovery session (a discovery session is started/stopped with methods in
> +org.bluez.Adapter1 interface).
> +
> +Advertisement Monitor hierarchy
> +===============================
> +Service org.bluez
> +Interface org.bluez.AdvertisementMonitor1
> +Object path freely definable
> +
> +Methods void Release() [noreply]
> +
> + This gets called as a signal for a client to perform
> + clean-up when (1)a monitor cannot be activated after it
> + was exposed or (2)a monitor has been deactivated.
> +
> + void Activate() [noreply]
> +
> + After a monitor was exposed, this gets called as a
> + signal for client to get acknowledged when a monitor
> + has been activated, so the client can expect to receive
> + calls on DeviceFound() or DeviceLost().
> +
> + void DeviceFound(object device) [noreply]
> +
> + This gets called to notify the client of finding the
> + targeted device. Once receiving the call, the client
> + should start to monitor the corresponding device to
> + retrieve the changes on RSSI and advertisement content.
> +
> + void DeviceLost(object device) [noreply]
> +
> + This gets called to notify the client of losing the
> + targeted device. Once receiving this call, the client
> + should stop monitoring the corresponding device.
> +
> +Properties uint8 Type [read-only]
> +
> + The type of the monitor. See SupportedMonitorTypes in
> + org.bluez.AdvertisementMonitorManager1 for the available
> + options.
> +
> + (Int16, Uint16, Int16, Uint16) RSSIThreshholdsAndTimers [read-only, optional]
> +
> + This contains HighRSSIThreshold, HighRSSIThresholdTimer,
> + LowRSSIThreshold, LowRSSIThresholdTimer in order. The
> + unit of HighRSSIThreshold and LowRSSIThreshold is dBm.
> + The unit of HighRSSIThresholdTimer and
> + LowRSSIThresholdTimer is second.
> +
> + If these are provided, RSSI would be used as a factor to
> + notify the client of whether a device stays in range or
> + move out of range. A device is considered in-range when
> + the RSSIs of the received advertisement(s) during
> + HighRSSIThresholdTimer seconds exceed HighRSSIThreshold.
> + Likewise, a device is considered out-of-range when the
> + RSSIs of the received advertisement(s) during
> + LowRSSIThresholdTimer do not reach LowRSSIThreshold.
> +
> + array{(uint8, uint8, string)} Patterns [read-only, optional]
> +
> + If Type is set to 0x01, this must exist and has at least
> + one entry in the array.
> +
> + The structure of a pattern contains the following.
> + uint8 start_position
> + The index in an AD data field where the search
> + should start. The beginning of an AD data field
> + is index 0.
> + uint8 AD_data_type
> + See https://www.bluetooth.com/specifications/
> + assigned-numbers/generic-access-profile/ for
> + the possible allowed value.
> + string content_of_pattern
> + This is the value of the pattern.
> +
> +=======================================
> +Service org.bluez
> +Interface org.bluez.AdvertisementMonitorManager1
> +Object path /org/bluez/{hci0,hci1,...}
> +Methods void RegisterApplication(object application)
> +
> + This registers a hierarchy of advertisement monitors.
> + The application object path together with the D-Bus
> + system bus connection ID define the identification of
> + the application registering advertisement monitors.
> +
> + Possible errors: org.bluez.Error.InvalidArguments
> + org.bluez.Error.AlreadyExists
> +
> + void UnregisterApplication(object application)
> +
> + This unregisters advertisement monitors that have been
> + previously registered. The object path parameter must
> + match the same value that has been used on
> + registration.
> +
> + Possible errors: org.bluez.Error.InvalidArguments
> + org.bluez.Error.DoesNotExist
> +
> +Properties array{uint8} SupportedMonitorTypes [read-only]
> +
> + This lists the supported types of advertisement
> + monitors. An application should check this before
> + instantiate and expose an object of
> + org.bluez.AdvertisementMonitor1.
> +
> + Possible values for monitor types:
> +
> + 0x01 Patterns with logic OR applied. With this type,
> + property "Patterns" must exist and has at least
> + one pattern.
Perhaps we should also have this as string, D-Bus don't really support
enums and it makes the types easier to debug if we express in them as
strings.
> +
> + array{string} SupportedFeatures [read-only]
> +
> + This lists the features of advertisement monitoring
> + supported by BlueZ.
> +
> + Possible values for features:
> +
> + "controller-based-monitor-by-patterns"
> + If the controller is capable of performing
> + advertisement monitoring by patterns, BlueZ
> + would offload the patterns to the controller to
> + reduce power consumption.
> --
> 2.24.1
Other than that it looks good to me, the only thing Id mark this
interface as experimental for now so we still allow changes if we deem
necessary.
--
Luiz Augusto von Dentz
