fix: use os-agnositc systemd detection, remove sysv in RPM packaging (#10570)

scripts/rpm/post-install.sh

@@ -1,29 +1,5 @@
 #!/bin/bash
 
-BIN_DIR=/usr/bin
-LOG_DIR=/var/log/telegraf
-SCRIPT_DIR=/usr/lib/telegraf/scripts
-LOGROTATE_DIR=/etc/logrotate.d
-
-function install_init {
-    cp -f $SCRIPT_DIR/init.sh /etc/init.d/telegraf
-    chmod +x /etc/init.d/telegraf
-}
-
-function install_systemd {
-    cp -f $SCRIPT_DIR/telegraf.service $1
-    systemctl enable telegraf || true
-    systemctl daemon-reload || true
-}
-
-function install_update_rcd {
-    update-rc.d telegraf defaults
-}
-
-function install_chkconfig {
-    chkconfig --add telegraf
-}
-
 # Remove legacy symlink, if it exists
 if [[ -L /etc/init.d/telegraf ]]; then
     rm -f /etc/init.d/telegraf
@@ -48,41 +24,16 @@ if [[ ! -f /etc/telegraf/telegraf.conf ]] && [[ -f /etc/telegraf/telegraf.conf.s
    cp /etc/telegraf/telegraf.conf.sample /etc/telegraf/telegraf.conf
 fi
 
+# Set up log directories
+LOG_DIR=/var/log/telegraf
 test -d $LOG_DIR || mkdir -p $LOG_DIR
 chown -R -L telegraf:telegraf $LOG_DIR
 chmod 755 $LOG_DIR
 
-# Distribution-specific logic
-if [[ -f /etc/redhat-release ]] || [[ -f /etc/SuSE-release ]]; then
-    # RHEL-variant logic
-    if [[ "$(readlink /proc/1/exe)" == */systemd ]]; then
-        install_systemd /usr/lib/systemd/system/telegraf.service
-    else
-        # Assuming SysVinit
-        install_init
-        # Run update-rc.d or fallback to chkconfig if not available
-        if which update-rc.d &>/dev/null; then
-            install_update_rcd
-        else
-            install_chkconfig
-        fi
-    fi
-elif [[ -f /etc/os-release ]]; then
-    source /etc/os-release
-    if [[ "$NAME" = "Amazon Linux" ]]; then
-        # Amazon Linux 2+ logic
-        install_systemd /usr/lib/systemd/system/telegraf.service
-    elif [[ "$NAME" = "Amazon Linux AMI" ]]; then
-        # Amazon Linux logic
-        install_init
-        # Run update-rc.d or fallback to chkconfig if not available
-        if which update-rc.d &>/dev/null; then
-            install_update_rcd
-        else
-            install_chkconfig
-        fi
-    elif [[ "$NAME" = "Solus" ]]; then
-        # Solus logic
-        install_systemd /usr/lib/systemd/system/telegraf.service
-    fi
+# Set up systemd service - check if the systemd directory exists per:
+# https://www.freedesktop.org/software/systemd/man/sd_booted.html
+if [[ -d /run/systemd/system ]]; then
+    cp -f /usr/lib/telegraf/scripts/telegraf.service /usr/lib/systemd/system/telegraf.service
+    systemctl enable telegraf
+    systemctl daemon-reload
 fi

scripts/rpm/post-remove.sh

@@ -1,55 +1,19 @@
 #!/bin/bash
 
-function disable_systemd {
-    systemctl disable telegraf
-    rm -f $1
-}
+# Telegraf is no longer installed, remove from systemd
+if [[ "$1" = "0" ]]; then
+    rm -f /etc/default/telegraf
 
-function disable_update_rcd {
-    update-rc.d -f telegraf remove
-    rm -f /etc/init.d/telegraf
-}
-
-function disable_chkconfig {
-    chkconfig --del telegraf
-    rm -f /etc/init.d/telegraf
-}
-
-if [[ -f /etc/redhat-release ]] || [[ -f /etc/SuSE-release ]]; then
-    # RHEL-variant logic
-    if [[ "$1" = "0" ]]; then
-        # InfluxDB is no longer installed, remove from init system
-        rm -f /etc/default/telegraf
-
-        if [[ "$(readlink /proc/1/exe)" == */systemd ]]; then
-            disable_systemd /usr/lib/systemd/system/telegraf.service
-        else
-            # Assuming sysv
-            disable_chkconfig
-        fi
-    fi
-    if [[ $1 -ge 1 ]]; then
-        # Package upgrade, not uninstall
-
-        if [[ "$(readlink /proc/1/exe)" == */systemd ]]; then
-            systemctl try-restart telegraf.service >/dev/null 2>&1 || :
-        fi
-    fi
-elif [[ -f /etc/os-release ]]; then
-    source /etc/os-release
-    if [[ "$ID" = "amzn" ]] && [[ "$1" = "0" ]]; then
-        # InfluxDB is no longer installed, remove from init system
-        rm -f /etc/default/telegraf
-
-        if [[ "$NAME" = "Amazon Linux" ]]; then
-            # Amazon Linux 2+ logic
-            disable_systemd /usr/lib/systemd/system/telegraf.service
-        elif [[ "$NAME" = "Amazon Linux AMI" ]]; then
-            # Amazon Linux logic
-            disable_chkconfig
-        fi
-    elif [[ "$NAME" = "Solus" ]]; then
-        rm -f /etc/default/telegraf
-        disable_systemd /usr/lib/systemd/system/telegraf.service
+    if [[ -d /run/systemd/system ]]; then
+        systemctl disable telegraf
+        rm -f /usr/lib/systemd/system/telegraf.service
+        systemctl daemon-reload
+    fi
+fi
+
+# Telegraf upgrade, restart service
+if [[ $1 -ge 1 ]]; then
+    if [[ -d /run/systemd/system ]]; then
+        systemctl try-restart telegraf.service >/dev/null 2>&1 || :
     fi
 fi