Update preinstall script to update agent config from V2 to V3

internal/collector/otelcol.tmpl

@@ -1,8 +1,12 @@
 receivers:
 {{- if ne .Receivers.HostMetrics nil }}
   hostmetrics:
+    {{- if .Receivers.HostMetrics.CollectionInterval }}
     collection_interval: {{ .Receivers.HostMetrics.CollectionInterval }}
+    {{- end}}
+    {{- if .Receivers.HostMetrics.InitialDelay }}
     initial_delay: {{ .Receivers.HostMetrics.InitialDelay }}
+    {{- end}}
     scrapers:
       {{- if .Receivers.HostMetrics.Scrapers }}
       {{- if .Receivers.HostMetrics.Scrapers.CPU }}

scripts/packages/preinstall.sh

@@ -6,17 +6,15 @@ set -e
 # Description:
 # NGINX Agent install script for downloading the NGINX Agent package from the appropriate repository
 #
-################################
-###### Changeable variables
-################################
-
-LOG_LEVEL=""
-
 ################################
 ###### Default variables
 ################################
+export NGINX_ONE_HOST="${NGINX_AGENT_SERVER_HOST:-agent.connect.nginx.com}"
 export AGENT_GROUP="${AGENT_GROUP:-$(id -ng)}"
 
+RED_COLOUR='\033[0;31m'
+NO_COLOUR='\033[0m'
+
 # Determine OS platform
 # shellcheck source=/dev/null
 . /etc/os-release
@@ -45,34 +43,92 @@ ensure_sudo() {
 }
 
 update_config_file() {
-    sed_cmd="sed -i.bak "
-
-    if [ ! -f "$AGENT_CONFIG_FILE" ]; then
-        printf "NGINX Agent config file %s does not exist. Could not be updated\n" "$AGENT_CONFIG_FILE"
-        exit 0
-    fi
+    echo "Checking what version of NGINX Agent is already installed"
+    check_version="nginx-agent --version"
+    nginx_agent_version=$($check_version 2>&1) || true
+    if [ -z "${nginx_agent_version##nginx-agent version v2*}" ]; then
+        echo "Updating NGINX Agent V2 configuration to V3 configuration"
+        echo "Backing up NGINX Agent V2 configuration to /etc/nginx-agent/nginx-agent-v2-backup.conf"
+        cp $AGENT_CONFIG_FILE /etc/nginx-agent/nginx-agent-v2-backup.conf
+
+        v2_config_file=$AGENT_CONFIG_FILE
+        v3_config_file=$AGENT_CONFIG_FILE
+
+        echo "NGINX Agent server host should be ${NGINX_ONE_HOST}"
+
+        if grep -q "$NGINX_ONE_HOST" ${v2_config_file}; then
+            echo "NGINX Agent is configured to connect to NGINX One"
+        else 
+            echo "${RED_COLOUR}Previous version of NGINX Agent was not configured to connect to NGINX One. Stopping upgrade${NO_COLOUR}" 
+            exit 1
+        fi
+
+        token=`grep "token:" "${v2_config_file}"`
+        token=`echo $token | cut -d ":" -f 2 | xargs`
+
+        config_dirs=`grep "config_dirs:" "${v2_config_file}"`
+        config_dirs=`echo $config_dirs | cut -d "\"" -f 2`
+
+        allowed_directories=""
+        IFS=":"
+        for config_dir in $config_dirs; do
+          allowed_directories="${allowed_directories}\n  - ${config_dir}"
+        done
+
+        allowed_directories="${allowed_directories}\n  - /var/log/nginx"
+
+        v3_config_contents="
+#
+# /etc/nginx-agent/nginx-agent.conf
+#
+# Configuration file for NGINX Agent.
+#
 
-    if [ "${PACKAGE_HOST}" ]; then
-        printf "Updating %s ...\n" "${AGENT_CONFIG_FILE}"
+log:
+  # set log level (error, info, debug; default \"info\")
+  level: info
+  # set log path. if empty, don't log to file.
+  path: /var/log/nginx-agent/
 
-        # Replace Host
-        ${sed_cmd} "s/host:.*$/host: ${PACKAGE_HOST}/" "${AGENT_CONFIG_FILE}"
-    fi
-
-    # Check the log-level and set accordingly
-    if [ "${LOG_LEVEL}" ]; then
-        if [ "$(grep -cP '^(?=[\s]*+[^#])[^#]*(level:)' "${AGENT_CONFIG_FILE}")" -ge 1 ]; then
-            printf "Setting existing log level: %s\n" "${LOG_LEVEL}"
-            ${sed_cmd} "/^[[:space:]]*#/!s/\(level:.*\)/level: ${LOG_LEVEL}/g" "${AGENT_CONFIG_FILE}"
-        else
-            printf "Setting log level: %s\n" "${LOG_LEVEL}"
-            _log_level_replacement="s/^log:/log:\\
-  level: ${LOG_LEVEL}/"
+allowed_directories: ${allowed_directories}
 
-            ${sed_cmd} "${_log_level_replacement}" "${AGENT_CONFIG_FILE}"
-            printf "Successfully updated %s\n" "${AGENT_CONFIG_FILE}"
-        fi
-        printf "Successfully updated %s\n" "${AGENT_CONFIG_FILE}"
+command:
+    server:
+        host: ${NGINX_ONE_HOST}
+        port: 443
+    auth:
+        token: ${token}
+    tls:
+        skip_verify: false
+
+collector:
+  receivers:
+    host_metrics:
+      scrapers:
+        cpu: {}
+        memory: {}
+        disk: {}
+        network: {}
+        filesystem: {}
+  processors:
+    batch: {}
+  exporters:
+    otlp_exporters:
+      - server:
+          host: ${NGINX_ONE_HOST}
+          port: 443
+        authenticator: headers_setter
+        tls:
+          skip_verify: false
+  extensions:
+    headers_setter:
+      headers:
+        - action: insert
+          key: \"authorization\"
+          value: ${token}
+        "
+
+        echo "${v3_config_contents}" > $v3_config_file
     fi
 }
 

scripts/packages/upgrade-agent-config.sh

@@ -0,0 +1,109 @@
+#!/bin/sh
+set -e
+
+# Copyright (C) Nginx, Inc. 2022.
+#
+# Description:
+# NGINX Agent script for converting NGINX AGENT V2 config format to V3 config format
+
+export NGINX_ONE_HOST="${NGINX_AGENT_SERVER_HOST:-agent.connect.nginx.com}"
+
+RED_COLOUR='\033[0;31m'
+NO_COLOUR='\033[0m'
+
+for i in "$@"; do
+  case $i in
+    --v2-config-file=*)
+      v2_config_file="${i#*=}"
+      shift
+      ;;
+    --v3-config-file=*)
+      v3_config_file="${i#*=}"
+      shift
+      ;;
+    -*|--*)
+      echo "Unknown option $i"
+      exit 1
+      ;;
+    *)
+      ;;
+  esac
+done
+
+echo "NGINX Agent server host should be ${NGINX_ONE_HOST}"
+
+if grep -q "$NGINX_ONE_HOST" ${v2_config_file}; then
+    echo "NGINX Agent is configured to connect to NGINX One"
+else 
+    echo "${RED_COLOUR}Previous version of NGINX Agent was not configured to connect to NGINX One. Stopping upgrade${NO_COLOUR}" 
+    exit 1
+fi
+
+token=`grep "token:" "${v2_config_file}"`
+token=`echo $token | cut -d ":" -f 2 | xargs`
+
+config_dirs=`grep "config_dirs:" "${v2_config_file}"`
+config_dirs=`echo $config_dirs | cut -d "\"" -f 2`
+
+allowed_directories=""
+IFS=":"
+for config_dir in $config_dirs; do
+  allowed_directories="${allowed_directories}\n  - ${config_dir}"
+done
+
+allowed_directories="${allowed_directories}\n  - /var/log/nginx"
+
+v3_config_contents="
+#
+# /etc/nginx-agent/nginx-agent.conf
+#
+# Configuration file for NGINX Agent.
+#
+
+log:
+  # set log level (error, info, debug; default \"info\")
+  level: info
+  # set log path. if empty, don't log to file.
+  path: /var/log/nginx-agent/
+
+allowed_directories: ${allowed_directories}
+
+command:
+    server:
+        host: ${NGINX_ONE_HOST}
+        port: 443
+    auth:
+        token: ${token}
+    tls:
+        skip_verify: false
+
+collector:
+  receivers:
+    host_metrics:
+      scrapers:
+        cpu: {}
+        memory: {}
+        disk: {}
+        network: {}
+        filesystem: {}
+  processors:
+    batch: {}
+  exporters:
+    otlp_exporters:
+      - server:
+          host: ${NGINX_ONE_HOST}
+          port: 443
+        authenticator: headers_setter
+        tls:
+          skip_verify: false
+  extensions:
+    headers_setter:
+      headers:
+        - action: insert
+          key: \"authorization\"
+          value: ${token}
+"
+
+echo "${v3_config_contents}" > $v3_config_file
+
+echo "NGINX Agent configuration successfully upgraded"

test/docker/nginx-official-image/apk/Dockerfile

@@ -12,6 +12,7 @@ WORKDIR /agent
 COPY ./build/${PACKAGE_NAME}.apk /agent/build/${PACKAGE_NAME}.apk
 COPY ./ /agent
 
+RUN apk del nginx-agent
 RUN apk add --allow-untrusted /agent/build/${PACKAGE_NAME}.apk
 
 RUN unlink /var/log/nginx/access.log

test/docker/nginx-official-image/deb/Dockerfile

@@ -13,7 +13,8 @@ WORKDIR /agent
 COPY ./build/${PACKAGE_NAME}.deb /agent/build/${PACKAGE_NAME}.deb
 COPY ./ /agent
 
-RUN  apt-get update \ 
+RUN  apt-get update \
+    && apt purge -y nginx-agent \
     && apt install --no-install-recommends --no-install-suggests -y /agent/build/${PACKAGE_NAME}.deb \ 
     &&  rm /agent/build/${PACKAGE_NAME}.deb