From 2625cc09a5215c2f1f165197154a4c22f4ba6a3a Mon Sep 17 00:00:00 2001
From: Christian Hesse <mail@eworm.de>
Date: Sat, 13 Nov 2021 21:29:33 +0100
Subject: [PATCH] check-health: support hard lower limit for voltage

... to detect slow decrease of voltage, for example with UPS.
---
 check-health          | 12 ++++++++++++
 doc/check-health.md   |  3 ++-
 global-config         |  3 ++-
 global-config-overlay |  2 +-
 global-config.changes |  1 +
 global-functions      |  2 +-
 6 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/check-health b/check-health
index 9fef8bc..56413c1 100644
--- a/check-health
+++ b/check-health
@@ -14,6 +14,7 @@
 :global CheckHealthTemperature;
 :global CheckHealthTemperatureDeviation;
 :global CheckHealthTemperatureNotified;
+:global CheckHealthVoltageLow;
 :global CheckHealthVoltagePercent;
 :global Identity;
 
@@ -52,6 +53,17 @@ $ScriptLock $0;
         message=("The " . $Name . " on " . $Identity . " jumped more than " . $CheckHealthVoltagePercent . "%.\n\n" . \
           "old value: " . [ $FormatVoltage ($CheckHealthLast->$Name) ] . "\n" . \
           "new value: " . [ $FormatVoltage $Voltage ]) });
+    } else={ 
+      :if ($Voltage <= $CheckHealthVoltageLow && $CheckHealthLast->$Name > $CheckHealthVoltageLow) do={ 
+        $SendNotification2 ({ origin=$0; \ 
+          subject=([ $SymbolForNotification "high-voltage-sign,chart-decreasing" ] . "Health warning: Low " . $Name); \ 
+          message=("The " . $Name . " on " . $Identity . " dropped to " . [ $FormatVoltage $Voltage ] . " below hard limit.") }); 
+      } 
+      :if ($Voltage > $CheckHealthVoltageLow && $CheckHealthLast->$Name <= $CheckHealthVoltageLow) do={ 
+        $SendNotification2 ({ origin=$0; \ 
+          subject=([ $SymbolForNotification "high-voltage-sign,chart-increasing" ] . "Health recovery: Low " . $Name); \ 
+          message=("The " . $Name . " on " . $Identity . " recovered to " . [ $FormatVoltage $Voltage ] . " above hard limit.") }); 
+      }
     }
   }
 }
diff --git a/doc/check-health.md b/doc/check-health.md
index 9e9e501..8e271d6 100644
--- a/doc/check-health.md
+++ b/doc/check-health.md
@@ -12,7 +12,7 @@ Description
 This script is run from scheduler periodically, sending notification on
 health related events:
 
-* voltage jumps up or down more than configured threshold
+* voltage jumps up or down more than configured threshold or drops below limit
 * power supply failed or recovered
 * temperature is above or below threshold
 
@@ -53,6 +53,7 @@ Configuration
 The configuration goes to `global-config-overlay`, these are the parameters:
 
 * `CheckHealthTemperature`: an array specifying temperature thresholds for sensors
+* `CheckHealthVoltageLow`: value (in volt*10) giving a hard lower limit
 * `CheckHealthVoltagePercent`: percentage value to trigger voltage jumps
 
 Also notification settings are required for e-mail, matrix and/or telegram.
diff --git a/global-config b/global-config
index 5f533b4..26e1a76 100644
--- a/global-config
+++ b/global-config
@@ -8,7 +8,7 @@
 
 # Make sure all configuration properties are up to date and this
 # value is in sync with value in script 'global-functions'!
-:global GlobalConfigVersion 68;
+:global GlobalConfigVersion 69;
 
 # This is used for DNS and backup file.
 :global Domain "example.com";
@@ -105,6 +105,7 @@
 }
 # This is deviation on recovery threshold against notification flooding.
 :global CheckHealthTemperatureDeviation 2;
+:global CheckHealthVoltageLow 115;
 :global CheckHealthVoltagePercent 10;
 
 # Access-list entries matching this comment are updated
diff --git a/global-config-overlay b/global-config-overlay
index 4f8eee5..87abb87 100644
--- a/global-config-overlay
+++ b/global-config-overlay
@@ -8,7 +8,7 @@
 # Make sure all configuration properties are up to date and this
 # value is in sync with value in script 'global-functions'!
 # Comment or remove to disable news and change notifications.
-:global GlobalConfigVersion 68;
+:global GlobalConfigVersion 69;
 
 # Copy configuration from global-config here and modify it.
 
diff --git a/global-config.changes b/global-config.changes
index 2914ea9..a8198db 100644
--- a/global-config.changes
+++ b/global-config.changes
@@ -72,6 +72,7 @@
   66="Moved script 'bridge-port-to-default' to new module.";
   67="Moved modules to directory with shorter name.";
   68="Reintroduced 'global-wait' for functions in scheduler.";
+  69="Support hard lower limit for voltage in 'check-health'.";
 };
 
 # Migration steps to be applied on script updates
diff --git a/global-functions b/global-functions
index 19f5777..3ec3e3e 100644
--- a/global-functions
+++ b/global-functions
@@ -8,7 +8,7 @@
 # https://git.eworm.de/cgit/routeros-scripts/about/
 
 # expected configuration version
-:global ExpectedConfigVersion 68;
+:global ExpectedConfigVersion 69;
 
 # global variables not to be changed by user
 :global GlobalFunctionsReady false;