From e6ab839098d87332af7ea7980bb1fe8fd439e58d Mon Sep 17 00:00:00 2001
From: Brian Candler <b.candler@pobox.com>
Date: Thu, 16 Dec 2021 17:23:02 +0000
Subject: [PATCH] Add node_os_info.sh collector

Signed-off-by: Brian Candler <b.candler@pobox.com>
---
 node_os_info.sh | 58 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)
 create mode 100755 node_os_info.sh

diff --git a/node_os_info.sh b/node_os_info.sh
new file mode 100755
index 0000000..ecb2e6b
--- /dev/null
+++ b/node_os_info.sh
@@ -0,0 +1,58 @@
+#!/bin/sh -e
+
+# Generate node_os_info and node_os_version metrics on legacy systems
+# which are not handled by node_exporter's own collector
+# (e.g. CentOS 6)
+
+[ -f /etc/os-release ] && exit 0
+[ -f /usr/lib/os-release ] && exit 0
+
+ID=""
+ID_LIKE=""
+NAME=""
+PRETTY_NAME=""
+VERSION=""
+VERSION_CODENAME=""
+VERSION_ID=""
+VERSION_METRIC=""
+
+if [ -f /etc/redhat-release ]; then
+  # CentOS release 6.10 (Final)
+  PRETTY_NAME="$(cat /etc/redhat-release)"
+  if [ -f /etc/centos-release ]; then
+    ID="centos"
+  elif [ -f /etc/oracle-release ]; then
+    ID="ol"
+  fi
+  ID_LIKE="rhel fedora"
+  NAME="$(expr "$PRETTY_NAME" : '\([^ ]*\)')" || true
+  VERSION="$(expr "$PRETTY_NAME" : '.* \([0-9].*\)')" || true
+  VERSION_ID="$(expr "$PRETTY_NAME" : '.* \([0-9][0-9.]*\)')" || true
+  # metric cannot distinguish 6.1 from 6.10, so only keep the integer part
+  VERSION_METRIC="$(expr "$VERSION_ID" : '\([0-9]*\)')" || true
+elif [ -f /etc/lsb-release ]; then
+  # DISTRIB_ID=Ubuntu
+  # DISTRIB_RELEASE=12.04
+  # DISTRIB_CODENAME=precise
+  # DISTRIB_DESCRIPTION="Ubuntu 12.04 LTS"
+  # Beware, old versions of CentOS with package "redhat-lsb-core" look like this instead:
+  # LSB_VERSION=base-4.0-amd64:base-4.0-noarch:core-4.0-amd64:core-4.0-noarch
+
+  # shellcheck disable=SC1091
+  . /etc/lsb-release
+  ID="$(echo "${DISTRIB_ID}" | tr '[:upper:]' '[:lower:]')"
+  NAME="${DISTRIB_ID}"
+  PRETTY_NAME="${DISTRIB_DESCRIPTION}"
+  VERSION="${DISTRIB_RELEASE} (${DISTRIB_CODENAME})"
+  VERSION_CODENAME="${DISTRIB_CODENAME}"
+  VERSION_ID="${DISTRIB_RELEASE}"
+  # 12.04.1 -> 12.04
+  VERSION_METRIC="$(expr "$VERSION_ID" : '\([0-9]*\|[0-9]*\.[0-9]*\)')" || true
+fi
+
+[ "$VERSION_METRIC" = "" ] && VERSION_METRIC="0"
+
+cat <<EOS
+node_os_info{id="$ID",id_like="$ID_LIKE",name="$NAME",pretty_name="$PRETTY_NAME",version="$VERSION",version_codename="$VERSION_CODENAME",version_id="$VERSION_ID"} 1
+node_os_version{id="$ID",id_like="$ID_LIKE",name="$NAME"} $VERSION_METRIC
+EOS