mapping sdr device layer

owrx/sdr.py

@@ -1,25 +1,59 @@
 from owrx.config import Config
-from owrx.property import PropertyLayer
+from owrx.property import PropertyManager, PropertyDeleted, PropertyDelegator, PropertyLayer
 from owrx.feature import FeatureDetector, UnknownFeatureException
 from owrx.source import SdrSourceState
+from functools import partial
 
 import logging
 
 logger = logging.getLogger(__name__)
 
 
-class SdrService(object):
-    sdrProps = None
-    sources = {}
-    lastPort = None
+class MappedSdrSources(PropertyDelegator):
+    def __init__(self, pm: PropertyManager):
+        self.subscriptions = {}
+        super().__init__(PropertyLayer())
+        for key, value in pm.items():
+            self._addSource(key, value)
+        pm.wire(self.handleSdrDeviceChange)
 
-    @staticmethod
-    def _loadProps():
-        if SdrService.sdrProps is None:
-            pm = Config.get()
+    def handleSdrDeviceChange(self, changes):
+        for key, value in changes.items():
+            if value is PropertyDeleted:
+                del self[key]
+            else:
+                self._addSource(key, value)
+
+    def handleDeviceUpdate(self, key, value, changes):
+        if self.isDeviceValid(value) and key not in self:
+            self._addSource(key, value)
+        elif not self.isDeviceValid(value) and key in self:
+            self._removeSource(key)
+
+    def _addSource(self, key, value):
+        if self.isDeviceValid(value):
+            self[key] = self.buildNewSource(key, value)
+        updateMethod = partial(self.handleDeviceUpdate, key, value)
+        self.subscriptions[key] = [
+            value.filter("type", "profiles").wire(updateMethod),
+            value["profiles"].wire(updateMethod)
+        ]
+
+    def _removeSource(self, key):
+        if key in self:
+            self[key].shutdown()
+        for sub in self.subscriptions[key]:
+            sub.cancel()
+        del self.subscriptions[key]
+
+    def isDeviceValid(self, device):
+        return self._hasProfiles(device) and self._sdrTypeAvailable(device)
+
+    def _hasProfiles(self, device):
+        return "profiles" in device and device["profiles"] and len(device["profiles"]) > 0
+
+    def _sdrTypeAvailable(self, value):
         featureDetector = FeatureDetector()
-
-            def sdrTypeAvailable(value):
         try:
             if not featureDetector.is_available(value["type"]):
                 logger.error(
@@ -35,15 +69,26 @@ class SdrService(object):
             )
             return False
 
-            # transform all dictionary items into PropertyManager object, filtering out unavailable ones
-            SdrService.sdrProps = {
-                name: value for (name, value) in pm["sdrs"].items() if sdrTypeAvailable(value)
-            }
-            logger.info(
-                "SDR sources loaded. Available SDRs: {0}".format(
-                    ", ".join(x["name"] for x in SdrService.sdrProps.values())
-                )
-            )
+    def buildNewSource(self, id, props):
+        sdrType = props["type"]
+        className = "".join(x for x in sdrType.title() if x.isalnum()) + "Source"
+        module = __import__("owrx.source.{0}".format(sdrType), fromlist=[className])
+        cls = getattr(module, className)
+        return cls(id, props)
+
+    def __setitem__(self, key, value):
+        if key in self:
+            self._removeSource(key)
+        super().__setitem__(key, value)
+
+    def __delitem__(self, key):
+        if key in self:
+            self._removeSource(key)
+        super().__delitem__(key)
+
+
+class SdrService(object):
+    sources = None
 
     @staticmethod
     def getFirstSource():
@@ -58,21 +103,14 @@ class SdrService(object):
         sources = SdrService.getSources()
         if not sources:
             return None
-        if not id in sources:
+        if id not in sources:
             return None
         return sources[id]
 
     @staticmethod
     def getSources():
-        SdrService._loadProps()
-        for id in SdrService.sdrProps.keys():
-            if id not in SdrService.sources:
-                props = SdrService.sdrProps[id]
-                sdrType = props["type"]
-                className = "".join(x for x in sdrType.title() if x.isalnum()) + "Source"
-                module = __import__("owrx.source.{0}".format(sdrType), fromlist=[className])
-                cls = getattr(module, className)
-                SdrService.sources[id] = cls(id, props)
+        if SdrService.sources is None:
+            SdrService.sources = MappedSdrSources(Config.get()["sdrs"])
         return {
             key: s
             for key, s in SdrService.sources.items()