From f31bdfdfb34edb36bc7c1498d6fbc4f4001cde7b Mon Sep 17 00:00:00 2001
From: Alex Brown <100519+alexpbrown@users.noreply.github.com>
Date: Wed, 17 Mar 2021 22:26:24 -0400
Subject: [PATCH] Add period char replacement for prometheus

This was a problem for me when trying to get output from an SDS011 Nova
PM sensor. When parsed by the pometheus code it returns labels / metrics
like:

```# TYPE tasmota_sensors_pm2.5_ gauge
tasmota_sensors_pm2.5_{sensor="sds0x1"} 2.2```

 The error from prometheus was:
 ```"append failed" err="invalid metric type \\"5_ gauge\\"```
---
 tasmota/xsns_75_prometheus.ino | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tasmota/xsns_75_prometheus.ino b/tasmota/xsns_75_prometheus.ino
index bbdb303c5..0b0251229 100644
--- a/tasmota/xsns_75_prometheus.ino
+++ b/tasmota/xsns_75_prometheus.ino
@@ -57,6 +57,7 @@ String FormatMetricName(const char *metric) {  // cleanup spaces and uppercases
   String formatted = metric;
   formatted.toLowerCase();
   formatted.replace(" ", "_");
+  formatted.replace(".", "_");
   return formatted;
 }