From ac90840d29355f4857732980afb116a6c920cfd4 Mon Sep 17 00:00:00 2001
From: Max <max@xolus.net>
Date: Tue, 26 Mar 2024 09:56:54 +0100
Subject: [PATCH] Protect against zero reads in counter

---
 solaredge_modbus.py |  3 ++-
 sunspec.py          | 20 ++++++++++++++++++--
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/solaredge_modbus.py b/solaredge_modbus.py
index 24acafb..01edc00 100644
--- a/solaredge_modbus.py
+++ b/solaredge_modbus.py
@@ -79,7 +79,8 @@ def main():
 
         yield (date, 'firmware_version', {'version': common.version}, 1)
         for (m,a,v) in export(inv, meters):
-            yield (date,m,a,v)
+            if v is not None:
+                yield (date,m,a,v)
             
         
     prom.run(collect, metric_data, 'SolarEdge Modbus/TCP Exporter\n', 
diff --git a/sunspec.py b/sunspec.py
index cf8eed3..994cfca 100644
--- a/sunspec.py
+++ b/sunspec.py
@@ -45,6 +45,16 @@ class Registers:
     def read_scale(self, address):
         return 10 ** self.read_int16(address)
 
+class Header:
+    def __init__(self, regs, base):
+        self.did = regs.read_uint16(0)
+        self.len = regs.read_uint16(1)
+        self.base = base
+        self.end = base + self.len
+
+    def __str__(self):
+        return f"SunSpec(DID={self.did}, [{self.base}:{self.end}]"
+
 class CommonBlock:
     def __init__(self, regs):
         self.did = regs.read_uint16(0)
@@ -98,7 +108,8 @@ class Meter:
             data = {}
             scale = regs.read_scale(offset + len(labels)*2)
             for (i, key) in enumerate(labels):
-                data[key] = regs.read_uint32(offset + 2*i) * scale / 10
+                value = regs.read_uint32(offset + 2*i) * scale / 10
+                data[key] = value if value > 1 else None
             self.__dict__[metric] = data
 
         self.frequency = regs.read_int16(14, scale=15)
@@ -130,7 +141,6 @@ class InverterBlock:
         self.ac_reactive_power = regs.read_int16(20, scale=21)
 
         self.power_factor = regs.read_int16(22, scale=23)
-        self.ac_energy = regs.read_uint32(24, scale=26)
         self.dc_current = regs.read_uint16(27, scale=28)
         self.dc_voltage = regs.read_uint16(29, scale=30)
         self.dc_power = regs.read_int16(31, scale=32)
@@ -139,6 +149,9 @@ class InverterBlock:
         self.status = status_codes[self.status_code]
         self.status_vendor = regs.read_uint16(39)
 
+        ac_energy = regs.read_uint32(24, scale=26)
+        self.ac_energy = ac_energy if ac_energy > 1 else None
+
 class Inverter:
     def __init__(self, host, port=1502, device=1):
         self._conn = ModbusTcpClient(host, port)
@@ -155,6 +168,9 @@ class Inverter:
         rs = self._conn.read_holding_registers(addr, length, slave=device)
         return Registers(rs, length)
 
+    def header(self, base):
+        return Header(self.registers(base, 2), base)
+
     def common_block(self):
         return CommonBlock(self.registers(40002, 67))