adding node exporter, loki, and promtail

loki/rootfs/etc/services.d/loki/finish

@@ -0,0 +1,14 @@
+#!/usr/bin/env bashio
+# ==============================================================================
+# Home Assistant  Add-on: Loki
+# Take down the S6 supervision tree when Loki fails
+# ==============================================================================
+
+declare APP_EXIT_CODE=${1}
+
+if [[ "${APP_EXIT_CODE}" -ne 0 ]] && [[ "${APP_EXIT_CODE}" -ne 256 ]]; then
+  bashio::log.warning "Halt add-on with exit code ${APP_EXIT_CODE}"
+  echo "${APP_EXIT_CODE}" > /run/s6-linux-init-container-results/exitcode
+  exec /run/s6/basedir/bin/halt
+fi
+

loki/rootfs/etc/services.d/loki/run

@@ -0,0 +1,51 @@
+#!/usr/bin/with-contenv bashio
+# shellcheck shell=bash
+# ==============================================================================
+# Home Assistant Add-on: Loki
+# Runs Loki
+# ==============================================================================
+
+readonly BIND_ADDR=127.0.0.1
+readonly HTTP_PORT=8080
+declare log_level
+loki_config='/etc/loki/default-config.yaml'
+
+bashio::log.info 'Starting Loki...'
+
+if bashio::config.exists 'config_path'; then
+    loki_config=$(bashio::config 'config_path')
+    bashio::log.info "Using config at ${loki_config}"
+else
+    bashio::log.info "Using default config"
+fi
+
+retention_period="$(bashio::config 'days_to_keep' 1)d"
+bashio::log.info "Retention period set to ${retention_period}"
+export "RETENTION_PERIOD=${retention_period}"
+
+case "$(bashio::config 'log_level')" in \
+    trace)      ;& \
+    debug)      log_level='debug' ;; \
+    notice)     ;& \
+    warning)    log_level='warn' ;; \
+    error)      ;& \
+    fatal)      log_level='error' ;; \
+    *)          log_level='info' ;; \
+esac;
+bashio::log.info "Loki log level set to ${log_level}"
+
+loki_args=(
+    "-config.expand-env=true"
+    "-config.file=${loki_config}"
+    "-server.http-listen-address=${BIND_ADDR}"
+    "-server.http-listen-port=${HTTP_PORT}" 
+    "-log.level=${log_level}"
+)
+if [ "${log_level}" == "debug" ]; then
+    bashio::log.debug "Logging full config on startup for debugging..."
+    loki_args+=("-print-config-stderr=true")
+fi
+
+bashio::log.info "Handing over control to Loki..."
+exec s6-setuidgid abc \
+    /usr/bin/loki "${loki_args[@]}"

loki/rootfs/etc/services.d/nginx/finish

@@ -0,0 +1,13 @@
+#!/usr/bin/env bashio
+# ==============================================================================
+# Home Assistant Add-on: Loki
+# Take down the S6 supervision tree when Nginx fails
+# ==============================================================================
+
+declare APP_EXIT_CODE=${1}
+
+if [[ "${APP_EXIT_CODE}" -ne 0 ]] && [[ "${APP_EXIT_CODE}" -ne 256 ]]; then
+  bashio::log.warning "Halt add-on with exit code ${APP_EXIT_CODE}"
+  echo "${APP_EXIT_CODE}" > /run/s6-linux-init-container-results/exitcode
+  exec /run/s6/basedir/bin/halt
+fi

loki/rootfs/etc/services.d/nginx/run

@@ -0,0 +1,10 @@
+#!/usr/bin/with-contenv bashio
+# shellcheck shell=bash
+# ==============================================================================
+# Home Assistant Add-on: Loki
+# Runs the Nginx daemon
+# ==============================================================================
+bashio::net.wait_for 8080
+bashio::log.info "Starting NGinx..."
+
+exec /usr/sbin/nginx