feat: init (WIP)

loki/.gitignore

@@ -0,0 +1,46 @@
+.idea
+logs
+
+
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### IntelliJ IDEA ###
+.idea/modules.xml
+.idea/jarRepositories.xml
+.idea/compiler.xml
+.idea/libraries/
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### Eclipse ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
+
+### Mac OS ###
+.DS_Store

loki/alloy/config.yaml

@@ -0,0 +1,59 @@
+version: '1'
+
+server:
+  log_level: info
+  grpc:
+    listen_address: 0.0.0.0:4317
+  http:
+    listen_address: 0.0.0.0:4318
+  prometheus:
+    listen_address: 0.0.0.0:9090
+
+pipelines:
+  logs:
+    - name: otlp_to_loki
+      receivers:
+        - otlp
+      processors:
+        - batch
+        - resourceattributes
+        - attributes
+      exporters:
+        - loki
+
+receivers:
+  otlp:
+    protocols:
+      grpc:
+        endpoint: 0.0.0.0:4317
+      http:
+        endpoint: 0.0.0.0:4318
+
+processors:
+  batch:
+    timeout: 1s
+    max_batch_size: 1000
+
+  resourceattributes:
+    actions:
+      - key: service.name
+        action: upsert
+        value: "opentelemetry-log4j2-alloy"
+
+  attributes:
+    actions:
+      - key: loki.attribute.labels
+        action: upsert
+        value: "service.name,service.version,log.level,severity"
+
+exporters:
+  loki:
+    endpoint: http://loki:3100/loki/api/v1/push
+    tenant_id: "alloy"
+    labels:
+      resource:
+        service.name: "service_name"
+        service.version: "service_version"
+      record:
+        severity: "severity"
+        log.level: "log_level"

loki/build.gradle.kts

@@ -0,0 +1,35 @@
+plugins {
+    id("java")
+}
+
+group = "com.miti99"
+version = "1.0-SNAPSHOT"
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    annotationProcessor("org.projectlombok:lombok:1.18.30")
+
+    implementation("io.opentelemetry:opentelemetry-api:1.33.0")
+    implementation("io.opentelemetry:opentelemetry-sdk:1.33.0")
+    implementation("io.opentelemetry:opentelemetry-sdk-logs:1.33.0")
+    implementation("io.opentelemetry:opentelemetry-exporter-otlp:1.33.0")
+    implementation("io.opentelemetry.instrumentation:opentelemetry-log4j-appender-2.17:1.30.0-alpha")
+    implementation("io.opentelemetry.proto:opentelemetry-proto:1.0.0-alpha")
+
+    implementation("org.projectlombok:lombok:1.18.30")
+
+    implementation("org.apache.logging.log4j:log4j-api:2.20.0")
+    implementation("org.apache.logging.log4j:log4j-core:2.20.0")
+    implementation("org.apache.logging.log4j:log4j-slf4j2-impl:2.20.0")
+
+
+    testImplementation(platform("org.junit:junit-bom:5.10.0"))
+    testImplementation("org.junit.jupiter:junit-jupiter")
+}
+
+tasks.test {
+    useJUnitPlatform()
+}

loki/docker-compose.yml

@@ -0,0 +1,49 @@
+version: '3'
+
+services:
+  # Alloy (OpenTelemetry Collector)
+  alloy:
+    image: otel/opentelemetry-collector:latest
+    container_name: alloy
+    command: [ "--config=/etc/alloy/config.yaml" ]
+    volumes:
+      - ./alloy/config.yaml:/etc/alloy/config.yaml
+    ports:
+      - "4317:4317"  # OTLP gRPC
+      - "4318:4318"  # OTLP HTTP
+      - "9090:9090"  # Prometheus metrics
+    depends_on:
+      - loki
+    networks:
+      - otel-network
+
+  # Loki (Log Storage)
+  loki:
+    image: grafana/loki:2.9.2
+    container_name: loki
+    ports:
+      - "3100:3100"
+    command: -config.file=/etc/loki/local-config.yaml
+    networks:
+      - otel-network
+
+  # Grafana (Visualization)
+  grafana:
+    image: grafana/grafana:10.1.0
+    container_name: grafana
+    ports:
+      - "3000:3000"
+    environment:
+      - GF_AUTH_ANONYMOUS_ENABLED=true
+      - GF_AUTH_ANONYMOUS_ORG_ROLE=Admin
+      - GF_AUTH_DISABLE_LOGIN_FORM=true
+    volumes:
+      - ./grafana/provisioning:/etc/grafana/provisioning
+    depends_on:
+      - loki
+    networks:
+      - otel-network
+
+networks:
+  otel-network:
+    driver: bridge

loki/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,6 @@
+#Sun Apr 13 22:06:57 ICT 2025
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.12-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

loki/gradlew

@@ -0,0 +1,234 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+APP_NAME="Gradle"
+APP_BASE_NAME=${0##*/}
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+# Collect all arguments for the java command;
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+#     shell script including quotes and variable substitutions, so put them in
+#     double quotes to make sure that they get re-expanded; and
+#   * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"

loki/gradlew.bat

@@ -0,0 +1,89 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

loki/grafana/provisioning/dashboards/dashboards.yml

@@ -0,0 +1,11 @@
+apiVersion: 1
+
+providers:
+  - name: 'Logs Dashboard'
+    orgId: 1
+    folder: ''
+    type: file
+    disableDeletion: false
+    editable: true
+    options:
+      path: /etc/grafana/provisioning/dashboards

loki/grafana/provisioning/dashboards/logs-dashboard.json

@@ -0,0 +1,486 @@
+{
+  "annotations": {
+    "list": [
+      {
+        "builtIn": 1,
+        "datasource": {
+          "type": "grafana",
+          "uid": "-- Grafana --"
+        },
+        "enable": true,
+        "hide": true,
+        "iconColor": "rgba(0, 211, 255, 1)",
+        "name": "Annotations & Alerts",
+        "type": "dashboard"
+      }
+    ]
+  },
+  "editable": true,
+  "fiscalYearStartMonth": 0,
+  "graphTooltip": 0,
+  "id": 1,
+  "links": [],
+  "liveNow": false,
+  "panels": [
+    {
+      "datasource": {
+        "type": "loki",
+        "uid": "P8E80F9AEF21F6940"
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 24,
+        "x": 0,
+        "y": 0
+      },
+      "id": 1,
+      "options": {
+        "dedupStrategy": "none",
+        "enableLogDetails": true,
+        "prettifyLogMessage": false,
+        "showCommonLabels": false,
+        "showLabels": false,
+        "showTime": true,
+        "sortOrder": "Descending",
+        "wrapLogMessage": false
+      },
+      "targets": [
+        {
+          "datasource": {
+            "type": "loki",
+            "uid": "P8E80F9AEF21F6940"
+          },
+          "editorMode": "builder",
+          "expr": "{service_name=\"opentelemetry-log4j2-alloy\"}",
+          "queryType": "range",
+          "refId": "A"
+        }
+      ],
+      "title": "All Logs",
+      "type": "logs"
+    },
+    {
+      "datasource": {
+        "type": "loki",
+        "uid": "P8E80F9AEF21F6940"
+      },
+      "description": "Log count by severity level",
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "palette-classic"
+          },
+          "custom": {
+            "axisCenteredZero": false,
+            "axisColorMode": "text",
+            "axisLabel": "",
+            "axisPlacement": "auto",
+            "barAlignment": 0,
+            "drawStyle": "line",
+            "fillOpacity": 0.5,
+            "gradientMode": "none",
+            "hideFrom": {
+              "legend": false,
+              "tooltip": false,
+              "viz": false
+            },
+            "lineInterpolation": "linear",
+            "lineWidth": 1,
+            "pointSize": 5,
+            "scaleDistribution": {
+              "type": "linear"
+            },
+            "showPoints": "auto",
+            "spanNulls": false,
+            "stacking": {
+              "group": "A",
+              "mode": "none"
+            },
+            "thresholdsStyle": {
+              "mode": "off"
+            }
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              },
+              {
+                "color": "red",
+                "value": 80
+              }
+            ]
+          }
+        },
+        "overrides": [
+          {
+            "matcher": {
+              "id": "byName",
+              "options": "ERROR"
+            },
+            "properties": [
+              {
+                "id": "color",
+                "value": {
+                  "fixedColor": "red",
+                  "mode": "fixed"
+                }
+              }
+            ]
+          },
+          {
+            "matcher": {
+              "id": "byName",
+              "options": "WARN"
+            },
+            "properties": [
+              {
+                "id": "color",
+                "value": {
+                  "fixedColor": "orange",
+                  "mode": "fixed"
+                }
+              }
+            ]
+          },
+          {
+            "matcher": {
+              "id": "byName",
+              "options": "INFO"
+            },
+            "properties": [
+              {
+                "id": "color",
+                "value": {
+                  "fixedColor": "blue",
+                  "mode": "fixed"
+                }
+              }
+            ]
+          },
+          {
+            "matcher": {
+              "id": "byName",
+              "options": "DEBUG"
+            },
+            "properties": [
+              {
+                "id": "color",
+                "value": {
+                  "fixedColor": "green",
+                  "mode": "fixed"
+                }
+              }
+            ]
+          }
+        ]
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 0,
+        "y": 8
+      },
+      "id": 2,
+      "options": {
+        "legend": {
+          "calcs": [],
+          "displayMode": "list",
+          "placement": "bottom",
+          "showLegend": true
+        },
+        "tooltip": {
+          "mode": "single",
+          "sort": "none"
+        }
+      },
+      "targets": [
+        {
+          "datasource": {
+            "type": "loki",
+            "uid": "P8E80F9AEF21F6940"
+          },
+          "editorMode": "builder",
+          "expr": "sum by(severity) (count_over_time({service_name=\"opentelemetry-log4j2-alloy\"} | unwrap severity [$__interval]))",
+          "legendFormat": "{{severity}}",
+          "queryType": "range",
+          "refId": "A"
+        }
+      ],
+      "title": "Log Count by Severity",
+      "type": "timeseries"
+    },
+    {
+      "datasource": {
+        "type": "loki",
+        "uid": "P8E80F9AEF21F6940"
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 12,
+        "y": 8
+      },
+      "id": 3,
+      "options": {
+        "dedupStrategy": "none",
+        "enableLogDetails": true,
+        "prettifyLogMessage": false,
+        "showCommonLabels": false,
+        "showLabels": false,
+        "showTime": true,
+        "sortOrder": "Descending",
+        "wrapLogMessage": false
+      },
+      "targets": [
+        {
+          "datasource": {
+            "type": "loki",
+            "uid": "P8E80F9AEF21F6940"
+          },
+          "editorMode": "builder",
+          "expr": "{service_name=\"opentelemetry-log4j2-alloy\"} |= `error` or |= `exception`",
+          "queryType": "range",
+          "refId": "A"
+        }
+      ],
+      "title": "Errors and Exceptions",
+      "type": "logs"
+    },
+    {
+      "datasource": {
+        "type": "loki",
+        "uid": "P8E80F9AEF21F6940"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "thresholds"
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              },
+              {
+                "color": "yellow",
+                "value": 5
+              },
+              {
+                "color": "red",
+                "value": 10
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 8,
+        "x": 0,
+        "y": 16
+      },
+      "id": 4,
+      "options": {
+        "colorMode": "value",
+        "graphMode": "area",
+        "justifyMode": "auto",
+        "orientation": "auto",
+        "reduceOptions": {
+          "calcs": [
+            "sum"
+          ],
+          "fields": "",
+          "values": false
+        },
+        "textMode": "auto"
+      },
+      "pluginVersion": "10.1.0",
+      "targets": [
+        {
+          "datasource": {
+            "type": "loki",
+            "uid": "P8E80F9AEF21F6940"
+          },
+          "editorMode": "builder",
+          "expr": "sum(count_over_time({service_name=\"opentelemetry-log4j2-alloy\", severity=\"ERROR\"} [$__range]))",
+          "queryType": "instant",
+          "refId": "A"
+        }
+      ],
+      "title": "Total Errors",
+      "type": "stat"
+    },
+    {
+      "datasource": {
+        "type": "loki",
+        "uid": "P8E80F9AEF21F6940"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "thresholds"
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "blue",
+                "value": null
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 8,
+        "x": 8,
+        "y": 16
+      },
+      "id": 5,
+      "options": {
+        "colorMode": "value",
+        "graphMode": "area",
+        "justifyMode": "auto",
+        "orientation": "auto",
+        "reduceOptions": {
+          "calcs": [
+            "sum"
+          ],
+          "fields": "",
+          "values": false
+        },
+        "textMode": "auto"
+      },
+      "pluginVersion": "10.1.0",
+      "targets": [
+        {
+          "datasource": {
+            "type": "loki",
+            "uid": "P8E80F9AEF21F6940"
+          },
+          "editorMode": "builder",
+          "expr": "sum(count_over_time({service_name=\"opentelemetry-log4j2-alloy\"} [$__range]))",
+          "queryType": "instant",
+          "refId": "A"
+        }
+      ],
+      "title": "Total Logs",
+      "type": "stat"
+    },
+    {
+      "datasource": {
+        "type": "loki",
+        "uid": "P8E80F9AEF21F6940"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "palette-classic"
+          },
+          "custom": {
+            "axisCenteredZero": false,
+            "axisColorMode": "text",
+            "axisLabel": "",
+            "axisPlacement": "auto",
+            "fillOpacity": 80,
+            "gradientMode": "none",
+            "hideFrom": {
+              "legend": false,
+              "tooltip": false,
+              "viz": false
+            },
+            "lineWidth": 1,
+            "scaleDistribution": {
+              "type": "linear"
+            },
+            "thresholdsStyle": {
+              "mode": "off"
+            }
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 8,
+        "x": 16,
+        "y": 16
+      },
+      "id": 6,
+      "options": {
+        "barRadius": 0,
+        "barWidth": 0.97,
+        "groupWidth": 0.7,
+        "legend": {
+          "calcs": [],
+          "displayMode": "list",
+          "placement": "bottom",
+          "showLegend": true
+        },
+        "orientation": "auto",
+        "showValue": "auto",
+        "stacking": "none",
+        "tooltip": {
+          "mode": "single",
+          "sort": "none"
+        },
+        "xTickLabelRotation": 0,
+        "xTickLabelSpacing": 0
+      },
+      "pluginVersion": "10.1.0",
+      "targets": [
+        {
+          "datasource": {
+            "type": "loki",
+            "uid": "P8E80F9AEF21F6940"
+          },
+          "editorMode": "builder",
+          "expr": "sum by(severity) (count_over_time({service_name=\"opentelemetry-log4j2-alloy\"} | unwrap severity [$__range]))",
+          "legendFormat": "{{severity}}",
+          "queryType": "range",
+          "refId": "A"
+        }
+      ],
+      "title": "Log Distribution",
+      "type": "barchart"
+    }
+  ],
+  "refresh": "",
+  "schemaVersion": 38,
+  "style": "dark",
+  "tags": [],
+  "templating": {
+    "list": []
+  },
+  "time": {
+    "from": "now-6h",
+    "to": "now"
+  },
+  "timepicker": {},
+  "timezone": "",
+  "title": "OpenTelemetry Log4j2 Dashboard",
+  "uid": "otel-log4j2-dashboard",
+  "version": 1,
+  "weekStart": ""
+}

loki/grafana/provisioning/datasources/datasource.yml

@@ -0,0 +1,12 @@
+apiVersion: 1
+
+datasources:
+  - name: Loki
+    type: loki
+    access: proxy
+    url: http://loki:3100
+    version: 1
+    editable: true
+    isDefault: true
+    jsonData:
+      maxLines: 1000

loki/settings.gradle.kts

@@ -0,0 +1,2 @@
+rootProject.name = "try-loki"
+

loki/src/main/java/com/miti99/loki/LoggingExample.java

@@ -0,0 +1,104 @@
+package com.miti99.loki;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.ThreadContext;
+
+import java.util.Random;
+
+public class LoggingExample {
+    private static final Logger logger = LogManager.getLogger(LoggingExample.class);
+    private final Random random = new Random();
+
+    public void performLogging() {
+        logger.info("Starting logging example");
+
+        // Using MDC (Mapped Diagnostic Context) with ThreadContext
+        ThreadContext.put("requestId", generateRequestId());
+        ThreadContext.put("userId", "user-" + random.nextInt(1000));
+
+        try {
+            // Simulate a series of operations with logging
+            simulateUserAuthentication();
+            simulateDataProcessing();
+            simulateApiCall();
+        } finally {
+            // Clean up ThreadContext
+            ThreadContext.clearAll();
+        }
+
+        logger.info("Completed logging example");
+    }
+
+    private void simulateUserAuthentication() {
+        logger.info("User authentication started");
+
+        // Simulate processing time
+        sleep(200);
+
+        if (random.nextBoolean()) {
+            logger.info("User authentication successful");
+        } else {
+            logger.warn("User authentication required additional verification");
+            sleep(300);
+            logger.info("Secondary authentication successful");
+        }
+    }
+
+    private void simulateDataProcessing() {
+        logger.info("Data processing started");
+
+        // Simulate processing time
+        sleep(500);
+
+        // Log processing metrics
+        int recordsProcessed = random.nextInt(1000) + 100;
+        double processingTime = random.nextDouble() * 400;
+
+        logger.info("Processed {} records in {} ms", recordsProcessed, String.format("%.2f", processingTime));
+
+        // Occasionally log an error
+        if (random.nextInt(10) < 2) {
+            logger.error("Failed to process some records due to data corruption");
+        }
+    }
+
+    private void simulateApiCall() {
+        logger.info("External API call initiated");
+
+        // Simulate API call latency
+        int latency = random.nextInt(1000) + 100;
+        sleep(latency);
+
+        // Log response status
+        int statusCode = random.nextInt(10) < 8 ? 200 : 500;
+
+        if (statusCode == 200) {
+            logger.info("API call successful with latency {} ms", latency);
+        } else {
+            logger.error("API call failed with status code {}", statusCode);
+            sleep(300);
+            logger.info("Retrying API call");
+            statusCode = random.nextInt(10) < 9 ? 200 : 500;
+
+            if (statusCode == 200) {
+                logger.info("Retry successful");
+            } else {
+                logger.error("Retry also failed with status code {}", statusCode);
+            }
+        }
+    }
+
+    private String generateRequestId() {
+        return "req-" + Integer.toHexString(random.nextInt(0x1000000));
+    }
+
+    private void sleep(long millis) {
+        try {
+            Thread.sleep(millis);
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+            logger.warn("Sleep interrupted", e);
+        }
+    }
+}

loki/src/main/java/com/miti99/loki/Main.java

@@ -0,0 +1,93 @@
+package com.miti99.loki;
+
+import io.opentelemetry.api.OpenTelemetry;
+import io.opentelemetry.api.common.Attributes;
+import io.opentelemetry.exporter.otlp.logs.OtlpGrpcLogRecordExporter;
+import io.opentelemetry.sdk.OpenTelemetrySdk;
+import io.opentelemetry.sdk.logs.SdkLoggerProvider;
+import io.opentelemetry.sdk.logs.export.BatchLogRecordProcessor;
+import io.opentelemetry.sdk.resources.Resource;
+import io.opentelemetry.semconv.ResourceAttributes;
+import java.util.concurrent.TimeUnit;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+public class Main {
+    private static final Logger logger = LogManager.getLogger(Main.class);
+
+    public static void main(String[] args) {
+        // Configure OpenTelemetry
+        OpenTelemetry openTelemetry = configureOpenTelemetry();
+
+        // Start logging
+        logger.info("Application started");
+
+        // Run logging example
+        LoggingExample loggingExample = new LoggingExample();
+        loggingExample.performLogging();
+
+
+        // Generate some additional logs
+        generateSampleLogs();
+
+        logger.info("Application stopping");
+    }
+
+    private static OpenTelemetry configureOpenTelemetry() {
+        // Define service resource
+        Resource resource = Resource.getDefault()
+                .merge(Resource.create(Attributes.of(
+                        ResourceAttributes.SERVICE_NAME, "opentelemetry-log4j2-alloy",
+                        ResourceAttributes.SERVICE_VERSION, "1.0.0"
+                )));
+
+        // Configure OtlpGrpcLogRecordExporter - this will send logs to Alloy
+        OtlpGrpcLogRecordExporter logExporter = OtlpGrpcLogRecordExporter.builder()
+                .setEndpoint("http://localhost:4317") // Alloy OTLP endpoint
+                .build();
+
+        // Create SDK LoggerProvider
+        SdkLoggerProvider loggerProvider = SdkLoggerProvider.builder()
+                .setResource(resource)
+                .addLogRecordProcessor(BatchLogRecordProcessor.builder(logExporter)
+                        .setScheduleDelay(100, TimeUnit.MILLISECONDS)
+                        .build())
+                .build();
+
+        // Build OpenTelemetry SDK
+        OpenTelemetrySdk openTelemetrySdk = OpenTelemetrySdk.builder()
+                .setLoggerProvider(loggerProvider)
+                .build();
+
+        // Register a shutdown hook to close the SDK when the application exits
+        Runtime.getRuntime().addShutdownHook(new Thread(loggerProvider::close));
+
+        return openTelemetrySdk;
+    }
+
+    private static void generateSampleLogs() {
+        // Generate various log levels
+        logger.debug("This is a debug message");
+        logger.info("This is an info message");
+        logger.warn("This is a warning message");
+        logger.error("This is an error message");
+
+        // Generate a log with an exception
+        try {
+            throw new RuntimeException("Simulated exception");
+        } catch (Exception e) {
+            logger.error("Exception occurred during processing", e);
+        }
+
+        // Generate logs with different contexts
+        logger.info("User login successful", () -> "userId: 12345");
+        logger.info("Payment processed", () -> "amount: $199.99, orderId: ORD-98765");
+
+        // Add a slight delay to make logs more readable in the UI
+        try {
+            Thread.sleep(1000);
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+        }
+    }
+}

loki/src/main/resources/log4j2.xml

@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="WARN">
+  <Properties>
+    <Property name="service.name">opentelemetry-log4j2-alloy</Property>
+    <Property name="service.version">1.0.0</Property>
+  </Properties>
+
+  <Appenders>
+    <!-- Console Appender -->
+    <Console name="Console" target="SYSTEM_OUT">
+      <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
+    </Console>
+
+    <!-- OpenTelemetry Appender -->
+    <OpenTelemetry name="OpenTelemetryAppender">
+      <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
+    </OpenTelemetry>
+  </Appenders>
+
+  <Loggers>
+    <!-- Application Logger -->
+    <Logger name="com.miti99" level="debug" additivity="false">
+      <AppenderRef ref="Console"/>
+      <AppenderRef ref="OpenTelemetryAppender"/>
+    </Logger>
+
+    <!-- Root Logger -->
+    <Root level="info">
+      <AppenderRef ref="Console"/>
+      <AppenderRef ref="OpenTelemetryAppender"/>
+    </Root>
+  </Loggers>
+</Configuration>

loki/src/main/resources/otel-collector-config.yaml

@@ -0,0 +1,44 @@
+receivers:
+  otlp:
+    protocols:
+      grpc:
+        endpoint: 0.0.0.0:4317
+      http:
+        endpoint: 0.0.0.0:4318
+
+processors:
+  batch:
+    send_batch_size: 1000
+    timeout: 10s
+
+  resourcedetection:
+    detectors: [ env, system ]
+    timeout: 2s
+
+  attributes:
+    actions:
+      - key: service.name
+        action: upsert
+        value: "opentelemetry-log4j2-alloy"
+
+exporters:
+  logging:
+    loglevel: debug
+
+  loki:
+    endpoint: http://loki:3100/loki/api/v1/push
+    tenant_id: "alloy"
+    labels:
+      resource:
+        service.name: "service_name"
+        service.version: "service_version"
+      attributes:
+        severity: "severity"
+        log.level: "log_level"
+
+service:
+  pipelines:
+    logs:
+      receivers: [ otlp ]
+      processors: [ batch, resourcedetection, attributes ]
+      exporters: [ logging, loki ]