Switch fetcher service to log4j2 (#441)

## Summary
I noticed we were missing the core chronon fetcher logs during feature
lookup requests. As we anyway wanted to rip out the JUL & logback, I
went ahead and dropped those for a log4j2 properties file.

Confirmed that I am seeing the relevant fetcher logs from classes like
the SawtoothOnlineAggregator etc when I hit the service with a feature
look up request.

## Checklist
- [ ] Added Unit Tests
- [ ] Covered by existing CI
- [X] Integration tested
- [ ] Documentation update



<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **Refactor**
- Consolidated service deployment paths and streamlined startup
configuration.
- Improved metrics handling by conditionally enabling reporting based on
environment settings.

- **Chores**
  - Optimized resource packaging and removed legacy dependencies.
- Upgraded logging configuration to enhance performance and log
management.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: piyush-zlai

online/src/main/scala/ai/chronon/online/Metrics.scala

@@ -19,9 +19,13 @@ package ai.chronon.online
 import ai.chronon.api.Extensions._
 import ai.chronon.api.ScalaJavaConversions._
 import ai.chronon.api._
-import com.timgroup.statsd.Event
-import com.timgroup.statsd.NonBlockingStatsDClient
-import com.timgroup.statsd.NonBlockingStatsDClientBuilder
+import com.timgroup.statsd.{
+  Event,
+  NoOpStatsDClient,
+  NonBlockingStatsDClient,
+  NonBlockingStatsDClientBuilder,
+  StatsDClient
+}
 
 object Metrics {
   object Environment extends Enumeration {
@@ -131,14 +135,21 @@ object Metrics {
     // In the unix socket case port is configured to be 0
     val statsHost: String = System.getProperty("ai.chronon.metrics.host", "localhost")
     val statsPort: Int = System.getProperty("ai.chronon.metrics.port", "8125").toInt
+    // Can disable stats collection for local / dev environments
+    val statsEnabled: Boolean = System.getProperty("ai.chronon.metrics.enabled", "true").toBoolean
     val tagCache: TTLCache[Context, String] = new TTLCache[Context, String](
       { ctx => ctx.toTags.reverse.mkString(",") },
       { ctx => ctx },
       ttlMillis = 5 * 24 * 60 * 60 * 1000 // 5 days
     )
 
-    private val statsClient: NonBlockingStatsDClient =
-      new NonBlockingStatsDClientBuilder().prefix("ai.zipline").hostname(statsHost).port(statsPort).build()
+    private val statsClient: StatsDClient = {
+      if (statsEnabled) {
+        new NonBlockingStatsDClientBuilder().prefix("ai.zipline").hostname(statsHost).port(statsPort).build()
+      } else {
+        new NoOpStatsDClient()
+      }
+    }
 
   }
 
@@ -178,7 +189,7 @@ object Metrics {
         .append(s)
         .toString
 
-    @transient private lazy val stats: NonBlockingStatsDClient = Metrics.Context.statsClient
+    @transient private lazy val stats: StatsDClient = Metrics.Context.statsClient
 
     def increment(metric: String): Unit = stats.increment(prefix(metric), tags)
 

service/BUILD.bazel

@@ -1,11 +1,11 @@
 java_library(
     name = "lib",
     srcs = glob(["src/main/**/*.java"]),
+    resources = glob(["src/main/resources/**/*"]),
     visibility = ["//visibility:public"],
     deps = _SCALA_DEPS + _VERTX_DEPS + [
         "//online:lib",
         "//service_commons:lib",
-        maven_artifact("ch.qos.logback:logback-classic"),
         maven_artifact("com.typesafe:config"),
         maven_artifact("io.netty:netty-all"),
         maven_artifact("io.micrometer:micrometer-registry-statsd"),
@@ -51,4 +51,5 @@ jvm_binary(
     name = "service_assembly",
     main_class = "ai.chronon.service.ChrononServiceLauncher",
     runtime_deps = [":lib"],
+    resources = glob(["src/main/resources/**/*"]),
 )

service/src/main/resources/log4j2.properties

@@ -0,0 +1,29 @@
+status = warn
+
+# Console appender configuration
+appender.console.type = Console
+appender.console.name = Console
+appender.console.layout.type = PatternLayout
+appender.console.layout.pattern = %d{yyyy-MM-dd HH:mm:ss.SSS} [%level] %logger{36}: %msg%n
+
+# File appender configuration
+appender.file.type = RollingFile
+appender.file.name = File
+appender.file.fileName = /srv/zipline/fetcher/logs/zipline-fs.log
+appender.file.filePattern = /srv/zipline/fetcher/logs/zipline-fs.%i.log
+appender.file.layout.type = PatternLayout
+appender.file.layout.pattern = %d{yyyy-MM-dd HH:mm:ss.SSS} [%level] %logger{36}: %msg%n
+appender.file.policies.type = Policies
+appender.file.policies.size.type = SizeBasedTriggeringPolicy
+appender.file.policies.size.size = 100MB
+appender.file.strategy.type = DefaultRolloverStrategy
+appender.file.strategy.max = 30
+
+# Root logger
+rootLogger.level = info
+rootLogger.appenderRef.console.ref = Console
+rootLogger.appenderRef.file.ref = File
+
+# dial down io.micrometer logs as it is noisy
+logger.micrometer.name = io.micrometer
+logger.micrometer.level = ERROR