[Changelog] msg-pvm-code plugin

cooli4enko85

The "msg-pvm-code" plugin type is used to add PVM code for custom parsing logic.

More information about pvm can be retrieved in our Knowledge Base and blog.

Check the step-by-step guide on how to use it:
https://flespi.com/kb/msg-pvm-code-plugin

kial

PVM plugins now have access to the device telemetry. Thus the very common task for detecting parameter value change can now be easily solved with the following PVM code:

if optional #engine.ignition.status != optional telemetry[#engine.ignition.status]:
	// param in the message is not equal to its last known value
	true ==> #engine.ignition.changed

Here is an advanced example demonstrating check for the message timestamp, required if your device can send messages from the black box/history:

if is_set #engine.ignition.status && optional telemetry[#engine.ignition.status].timestamp < #timestamp:
	// we have "engine.ignition.status" parameter in current "fresh" message (not from black box)
	if #engine.ignition.status != telemetry[#engine.ignition.status]:
		// param in the message is not equal to its last known value
		true ==> #engine.ignition.changed

And here are few more examples of the device telemetry access syntax:

telemetry["driver.message"] ==> ...         // param name can be a string
telemetry[$param_name] ==> ...              // param name can be a variable
telemetry[#driver.message, boolean] ==> ... // return value type override
telemetry[$param_name].timestamp ==> ...    // time of the last parameter value

kial

PVM plugins now have access to the device metadata.

Here are few examples of the device metadata access syntax:

metadata["field"] ==> ...                   // field name can be a string
metadata[$field_name] ==> ...               // field name can be a variable
metadata["field", boolean] ==> ...          // field value type specification
optional metadata["field"] ==> ...          // chain executes only if field are set in the device metadata

if is_set metadata["field"]:
    ... // code will be executed only if field are set
if optional metadata["field"] == 42:
    ... // code will be executed only if field are set to value 42

kial

PVM plugins now have access to the device settings (https://flespi.com/kb/commands-and-settings).

One field of the current setting value can be fetched with such syntax:

:settingname.field ==> ... // note the colon char

Usual operators like is_set or optional is also available:

optional :settingname.field ==> ...
if is_set :settingname.field:
    ... // code executed only if setting field are set

The list of setting names and its fields (as JSON Schema) available for the device can be obtained with such REST API request

kial

Some time ago, string manipulation in PVM plugins was extended with new features:

lowercase, uppercase - for converting ASCII characters case in string values
replace[<what>=<which>] - for substring replace in string values
substring[offset=X, size=Y] or substring[start=X, stop=Y] - for extracting a part of a string value

See more details on https://flespi.com/kb/pvm-basics#string-operations

kial

PVM plugins now can calculate a distance between two points (given as coordinates), in several ways:

distance[<lat1>, <lon1>, <lat2>, <lon2>] - between two points explicitly given as coordinates
distance_to[<lat>, <lon>] - between position of the message and specific point given as coordinates
distance_last - between position of the message and last device position in telemetry

See more details on https://flespi.com/kb/pvm-basics#distance