Merge pull request #49 from openenergymonitor/emonhub_buffer

Emonhub buffer interim fix

src/emonhub.py

@@ -16,63 +16,23 @@
 import signal
 import argparse
 import pprint
-
-try:
-      import pymodbus
-      pymodbus_found = True
-except ImportError:
-      pymodbus_found = False
-
-try:
-      import bluetooth
-      bluetooth_found = True
-except ImportError:
-      bluetooth_found = False
-
+import glob, os
 
 import emonhub_setup as ehs
-import interfacers.emonhub_interfacer as ehi
 import emonhub_coder as ehc
+import emonhub_interfacer as ehi
+from interfacers import *
+
+# this namespace and path
+namespace = sys.modules[__name__]
+path = os.path.dirname(__file__)
 
-import interfacers.EmonHubSerialInterfacer
-import interfacers.EmonHubJeeInterfacer
-import interfacers.EmonHubSocketInterfacer
-import interfacers.EmonHubPacketGenInterfacer
-import interfacers.EmonHubMqttInterfacer
-import interfacers.EmonHubTesterInterfacer
-import interfacers.EmonHubEmoncmsHTTPInterfacer
-import interfacers.EmonHubSmilicsInterfacer
-import interfacers.EmonHubVEDirectInterfacer
-import interfacers.EmonHubGraphiteInterfacer
-import interfacers.EmonHubBMWInterfacer
-import interfacers.EmonHubTx3eInterfacer
-
-if bluetooth_found:
-    import interfacers.EmonHubSMASolarInterfacer
-
-if pymodbus_found:
-    import interfacers.EmonModbusTcpInterfacer
-    import interfacers.EmonFroniusModbusTcpInterfacer
-
-ehi.EmonHubSerialInterfacer = interfacers.EmonHubSerialInterfacer.EmonHubSerialInterfacer
-ehi.EmonHubJeeInterfacer = interfacers.EmonHubJeeInterfacer.EmonHubJeeInterfacer
-ehi.EmonHubSocketInterfacer = interfacers.EmonHubSocketInterfacer.EmonHubSocketInterfacer
-ehi.EmonHubPacketGenInterfacer = interfacers.EmonHubPacketGenInterfacer.EmonHubPacketGenInterfacer
-ehi.EmonHubMqttInterfacer = interfacers.EmonHubMqttInterfacer.EmonHubMqttInterfacer
-ehi.EmonHubTesterInterfacer = interfacers.EmonHubTesterInterfacer.EmonHubTesterInterfacer
-ehi.EmonHubEmoncmsHTTPInterfacer = interfacers.EmonHubEmoncmsHTTPInterfacer.EmonHubEmoncmsHTTPInterfacer
-ehi.EmonHubSmilicsInterfacer = interfacers.EmonHubSmilicsInterfacer.EmonHubSmilicsInterfacer
-ehi.EmonHubVEDirectInterfacer = interfacers.EmonHubVEDirectInterfacer.EmonHubVEDirectInterfacer
-ehi.EmonHubGraphiteInterfacer = interfacers.EmonHubGraphiteInterfacer.EmonHubGraphiteInterfacer
-ehi.EmonHubBMWInterfacer = interfacers.EmonHubBMWInterfacer.EmonHubBMWInterfacer
-ehi.EmonHubTx3eInterfacer = interfacers.EmonHubTx3eInterfacer.EmonHubTx3eInterfacer
-
-if bluetooth_found:
-    ehi.EmonHubSMASolarInterfacer = interfacers.EmonHubSMASolarInterfacer.EmonHubSMASolarInterfacer
-
-if pymodbus_found:
-    ehi.EmonModbusTcpInterfacer = interfacers.EmonModbusTcpInterfacer.EmonModbusTcpInterfacer
-    ehi.EmonFroniusModbusTcpInterfacer = interfacers.EmonFroniusModbusTcpInterfacer.EmonFroniusModbusTcpInterfacer
+# scan interfacers directory and import all interfacers
+for f in glob.glob(path+"/interfacers/*.py"):
+    name = f.replace(".py","").replace(path+"/interfacers/","")
+    if name!="__init__":
+        # print "Loading: "+name
+        setattr(ehi,name,getattr(getattr(namespace,name),name))
 
 """class EmonHub
 
@@ -86,7 +46,7 @@
 
 class EmonHub(object):
 
-    __version__ = "emonHub emon-pi variant v2.0.0"
+    __version__ = "emonHub emon-pi variant v2.1.0"
 
     def __init__(self, setup):
         """Setup an OpenEnergyMonitor emonHub.

src/emonhub_buffer.py

@@ -0,0 +1,115 @@
+"""
+
+  This code is released under the GNU Affero General Public License.
+  
+  OpenEnergyMonitor project:
+  http://openenergymonitor.org
+
+"""
+
+import logging
+
+"""class AbstractBuffer
+
+Represents the actual buffer being used.
+"""
+
+
+class AbstractBuffer():
+
+    def storeItem(self, data):
+        raise NotImplementedError
+
+    def retrieveItems(self, number):
+        raise NotImplementedError
+
+    def retrieveItem(self): 
+        raise NotImplementedError
+
+    def discardLastRetrievedItem(self):
+        raise NotImplementedError
+
+    def discardLastRetrievedItems(self, number):
+        raise NotImplementedError
+
+    def hasItems(self): 
+        raise NotImplementedError
+
+"""
+This implementation of the AbstractBuffer just uses an in-memory data structure.
+It's basically identical to the previous (inline) buffer.
+"""
+
+
+class InMemoryBuffer(AbstractBuffer):
+
+    def __init__(self, bufferName, buffer_size):
+        self._bufferName = str(bufferName)
+        self._buffer_type = "memory"
+        self._maximumEntriesInBuffer = int(buffer_size)
+        self._data_buffer = []
+        self._log = logging.getLogger("EmonHub")
+
+    def hasItems(self):
+        return self.size() > 0
+
+    def isFull(self):
+        return self.size() >= self._maximumEntriesInBuffer
+
+    def getMaxEntrySliceIndex(self):
+        return max(0,
+                   self.size() - self._maximumEntriesInBuffer - 1)
+
+    def discardOldestItems(self):
+        self._data_buffer = self._data_buffer[self.getMaxEntrySliceIndex():]
+
+    def discardOldestItemsIfFull(self):
+        if self.isFull():
+            self._log.warning(
+                "In-memory buffer (%s) reached limit of %d items, deleting oldest"
+                % (self._bufferName, self._maximumEntriesInBuffer))
+        self.discardOldestItems()
+
+    def storeItem(self, data):
+        self.discardOldestItemsIfFull()
+        self._data_buffer.append(data)
+
+    def retrieveItem(self):
+        return self._data_buffer[0]
+
+    def retrieveItems(self, number):
+        blen = len(self._data_buffer)
+        if number > blen:
+            number = blen
+        return self._data_buffer[:number]
+
+    def discardLastRetrievedItem(self):
+        del self._data_buffer[0]
+
+    def discardLastRetrievedItems(self, number):
+        blen = len(self._data_buffer)
+        if number > blen:
+            number = blen
+        self._data_buffer = self._data_buffer[number:]
+
+    def size(self):
+        return len(self._data_buffer)
+
+
+"""
+The getBuffer function returns the buffer class corresponding to a 
+buffering method passed as argument.
+"""
+bufferMethodMap = {
+                   'memory': InMemoryBuffer
+                  }
+
+
+def getBuffer(method):
+    """Returns the buffer class corresponding to the method
+
+    method (string): buffering method
+
+    """
+    return bufferMethodMap[method]
+