From c67b3e3cbdf944786b53001f98e82e217dc8cc89 Mon Sep 17 00:00:00 2001
From: Thomas Basler <thomas@familie-basler.net>
Date: Fri, 24 Feb 2023 19:10:35 +0100
Subject: [PATCH] Prometheus API: Set correct metrics type

---
 include/WebApi_prometheus.h | 25 +++++++++++++++++++++++++
 src/WebApi_prometheus.cpp   |  2 +-
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/include/WebApi_prometheus.h b/include/WebApi_prometheus.h
index ac2478a..5eb894e 100644
--- a/include/WebApi_prometheus.h
+++ b/include/WebApi_prometheus.h
@@ -3,6 +3,7 @@
 
 #include <ESPAsyncWebServer.h>
 #include <Hoymiles.h>
+#include <map>
 
 class WebApiPrometheusClass {
 public:
@@ -15,4 +16,28 @@ private:
     void addField(AsyncResponseStream* stream, String& serial, uint8_t idx, std::shared_ptr<InverterAbstract> inv, ChannelType_t type, ChannelNum_t channel, FieldId_t fieldId, const char* channelName = NULL);
 
     AsyncWebServer* _server;
+
+    enum {
+        METRIC_TYPE_NONE = 0,
+        METRIC_TYPE_GAUGE,
+        METRIC_TYPE_COUNTER,
+    };
+    const char* _metricTypes[3] = { 0, "gauge", "counter" };
+
+    std::map<FieldId_t, uint8_t> _fieldMetricAssignment {
+        { FLD_UDC, METRIC_TYPE_GAUGE },
+        { FLD_IDC, METRIC_TYPE_GAUGE },
+        { FLD_PDC, METRIC_TYPE_GAUGE },
+        { FLD_YD, METRIC_TYPE_COUNTER },
+        { FLD_YT, METRIC_TYPE_COUNTER },
+        { FLD_UAC, METRIC_TYPE_GAUGE },
+        { FLD_IAC, METRIC_TYPE_GAUGE },
+        { FLD_PAC, METRIC_TYPE_GAUGE },
+        { FLD_F, METRIC_TYPE_GAUGE },
+        { FLD_T, METRIC_TYPE_GAUGE },
+        { FLD_PF, METRIC_TYPE_GAUGE },
+        { FLD_EFF, METRIC_TYPE_GAUGE },
+        { FLD_IRR, METRIC_TYPE_GAUGE },
+        { FLD_PRA, METRIC_TYPE_GAUGE }
+    };
 };
\ No newline at end of file
diff --git a/src/WebApi_prometheus.cpp b/src/WebApi_prometheus.cpp
index a805ee8..28f0b94 100644
--- a/src/WebApi_prometheus.cpp
+++ b/src/WebApi_prometheus.cpp
@@ -105,7 +105,7 @@ void WebApiPrometheusClass::addField(AsyncResponseStream* stream, String& serial
         const char* chanName = (channelName == NULL) ? inv->Statistics()->getChannelFieldName(type, channel, fieldId) : channelName;
         if (idx == 0 && type == TYPE_AC && channel == 0) {
             stream->printf("# HELP opendtu_%s in %s\n", chanName, inv->Statistics()->getChannelFieldUnit(type, channel, fieldId));
-            stream->printf("# TYPE opendtu_%s gauge\n", chanName);
+            stream->printf("# TYPE opendtu_%s %s\n", chanName, _metricTypes[_fieldMetricAssignment[fieldId]]);
         }
         stream->printf("opendtu_%s{serial=\"%s\",unit=\"%d\",name=\"%s\",type=\"%s\",channel=\"%d\"} %f\n",
             chanName,