#115 Send Spring logs to Loki

Author: vityaman

backend/gradle/libs.versions.toml

@@ -25,6 +25,7 @@ org-jetbrains-kotlinx-kotlinx-coroutines = "1.9.0"
 io-projectreactor-kotlin-reactor-kotlin-extensions = "1.2.3"
 
 io-micrometer = "1.14.3"
+com-github-loki4j = "1.6.0"
 
 io-projectreactor-reactor-test = "3.6.11"
 junit-junit = "4.13.2"
@@ -79,6 +80,7 @@ org-postgresql-postgresql = { module = "org.postgresql:postgresql", version.ref
 org-postgresql-r2dbc-postgresql = { module = "org.postgresql:r2dbc-postgresql", version.ref = "org-postgresql-r2dbc-postgresql" }
 
 io-micrometer-micrometer-registry-prometheus = { module = "io.micrometer:micrometer-registry-prometheus", version.ref = "io-micrometer" }
+com-github-loki4j-loki-logback-appender = { module = "com.github.loki4j:loki-logback-appender", version.ref = "com-github-loki4j" }
 
 junit-junit = { module = "junit:junit", version.ref = "junit-junit" }
 org-testcontainers-postgresql = { module = "org.testcontainers:postgresql", version.ref = "org-testcontainers" }

backend/starter-monitoring/build.gradle.kts

@@ -8,4 +8,6 @@ dependencies {
 
     api(libs.org.springframework.boot.spring.boot.starter.actuator)
     api(libs.io.micrometer.micrometer.registry.prometheus)
+
+    api(libs.com.github.loki4j.loki.logback.appender)
 }

backend/starter-monitoring/src/main/resources/logback-spring.xml

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <springProperty scope="context" name="SERVICE_NAME" source="spring.application.name"/>
+    <appender name="LOKI" class="com.github.loki4j.logback.Loki4jAppender">
+        <http>
+            <url>http://loki.dating.se.ifmo.ru:3100/loki/api/v1/push</url>
+        </http>
+        <format>
+            <label>
+                <pattern>
+                    service_name=${SERVICE_NAME},
+                    host=${HOSTNAME},
+                    level=%level,
+                    logger=%logger{36},
+                </pattern>
+                <readMarkers>true</readMarkers>
+            </label>
+            <message>
+                <pattern>
+                    [%level] %logger{36}: %msg%n
+                </pattern>
+            </message>
+        </format>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="LOKI" />
+    </root>
+</configuration>