replace log4j with slf4j and logback

unfortunately spring-boot hard code support for an older slf4j and logback, but this is isolated in scenario

build-logic/src/main/kotlin/clusterless.java-application-conventions.gradle.kts

@@ -1,3 +1,6 @@
+import gradle.kotlin.dsl.accessors._4c82c8048bcef42aad7cd4b7a363d7d5.implementation
+import gradle.kotlin.dsl.accessors._4c82c8048bcef42aad7cd4b7a363d7d5.runtimeOnly
+
 /*
  * Copyright (c) 2023-2025 Chris K Wensel <[email protected]>. All Rights Reserved.
  *
@@ -7,14 +10,13 @@
  */
 
 plugins {
-    // Apply the common convention plugin for shared build configuration between library and application projects.
     id("clusterless.java-common-conventions")
-
-    // Apply the application plugin to add support for building a CLI application in Java.
     application
 }
 
 dependencies {
     implementation("info.picocli:picocli")
     implementation("com.github.jknack:handlebars")
+    runtimeOnly("ch.qos.logback:logback-classic")
+    runtimeOnly("ch.qos.logback:logback-core")
 }

build-logic/src/main/kotlin/clusterless.java-common-conventions.gradle.kts

@@ -89,9 +89,8 @@ fun DependencyConstraintHandlerScope.testImplementationAndTestFixture(constraint
 }
 
 dependencies {
-    implementation("org.apache.logging.log4j:log4j-api")
-    implementation("org.apache.logging.log4j:log4j-core")
-    implementation("org.apache.logging.log4j:log4j-jul")
+    implementation("org.slf4j:slf4j-api")
+
     implementation("org.jetbrains:annotations")
 
     compileOnly("javax.annotation:javax.annotation-api")
@@ -110,6 +109,13 @@ dependencies {
         implementation("com.github.jknack:handlebars:4.4.0")
 //        implementation("com.cronutils:cron-utils:9.2.0")
 
+        val slf4j = "2.0.16"
+        implementation("org.slf4j:slf4j-api:$slf4j")
+        val logback = "1.5.16"
+        implementation("ch.qos.logback:logback-classic:$logback")
+        implementation("ch.qos.logback:logback-core:$logback")
+
+        // only used by lambdas
         // https://mvnrepository.com/artifact/org.apache.logging.log4j
         val log4j = "2.24.3"
         implementation("org.apache.logging.log4j:log4j-api:$log4j")
@@ -181,7 +187,8 @@ dependencies {
         // https://github.com/testcontainers/testcontainers-java/issues/1442#issuecomment-694342883
         testImplementationAndTestFixture("com.amazonaws:aws-java-sdk-s3:1.11.860")
 
-        testImplementationAndTestFixture("org.apache.logging.log4j:log4j-slf4j-impl:$log4j")
+        testImplementationAndTestFixture("ch.qos.logback:logback-classic:$logback")
+        testImplementationAndTestFixture("ch.qos.logback:logback-core:$logback")
     }
 }
 
@@ -203,8 +210,6 @@ testing {
                 implementation("uk.org.webcompere:system-stubs-core")
                 implementation("uk.org.webcompere:system-stubs-jupiter")
                 implementation("org.mockito:mockito-inline")
-
-                implementation("org.apache.logging.log4j:log4j-slf4j-impl") // used by inject-resources
             }
         }
 

build-logic/src/main/kotlin/clusterless.java-lambda-conventions.gradle.kts

@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2023-2025 Chris K Wensel <[email protected]>. All Rights Reserved.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+plugins {
+    id("clusterless.java-common-conventions")
+    `java-library`
+}
+
+dependencies {
+}

build-logic/src/main/kotlin/clusterless.java-library-conventions.gradle.kts

@@ -7,9 +7,9 @@
  */
 
 plugins {
-    // Apply the common convention plugin for shared build configuration between library and application projects.
     id("clusterless.java-common-conventions")
-
-    // Apply the java-library plugin for API and implementation separation.
     `java-library`
 }
+
+dependencies {
+}

clusterless-common/src/main/java/clusterless/cls/config/ConfigManager.java

@@ -18,8 +18,8 @@
 import com.fasterxml.jackson.databind.node.JsonNodeFactory;
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.fasterxml.jackson.dataformat.toml.TomlMapper;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.*;
 import java.nio.file.Files;
@@ -37,7 +37,7 @@
  *
  */
 public class ConfigManager {
-    private static final Logger LOG = LogManager.getLogger(ConfigManager.class);
+    private static final Logger LOG = LoggerFactory.getLogger(ConfigManager.class);
     public static final Path CURRENT_DIR = Paths.get(".").toAbsolutePath().normalize();
     public static final Path HOME_DIR = Paths.get(System.getProperty("user.home")).toAbsolutePath().normalize();
     public static final Path GLOBAL_CONFIG_DIR = HOME_DIR.resolve(Paths.get(".cls"));

clusterless-main-common/build.gradle.kts

@@ -14,6 +14,8 @@ dependencies {
     implementation(project(":clusterless-common"))
     implementation(project(":clusterless-model"))
 
+    compileOnly("ch.qos.logback:logback-classic")
+
     implementation("io.heretical:mini-parsers-temporal")
     implementation("info.picocli:picocli")
     implementation("com.github.jknack:handlebars")

clusterless-main-common/src/main/java/clusterless/cls/process/ProcessExec.java

@@ -16,16 +16,15 @@
 import io.github.resilience4j.retry.MaxRetriesExceededException;
 import io.github.resilience4j.retry.Retry;
 import io.github.resilience4j.retry.RetryConfig;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 import java.time.Duration;
 import java.util.*;
 import java.util.function.Supplier;
 
 public abstract class ProcessExec {
-    private static final Logger LOG = LogManager.getLogger(ProcessExec.class);
+    private static final org.slf4j.Logger LOG = LoggerFactory.getLogger(ProcessExec.class);
     protected Supplier<Boolean> dryRun = () -> false;
     protected Supplier<Boolean> retry = () -> false;
     protected Supplier<Integer> verbosity = () -> 0;

clusterless-main-common/src/main/java/clusterless/cls/startup/Verbosity.java

@@ -8,10 +8,13 @@
 
 package clusterless.cls.startup;
 
-import org.apache.logging.log4j.Level;
-import org.apache.logging.log4j.core.config.Configurator;
+import ch.qos.logback.classic.Level;
+import ch.qos.logback.classic.LoggerContext;
+import org.slf4j.LoggerFactory;
 import picocli.CommandLine;
 
+import static org.slf4j.Logger.ROOT_LOGGER_NAME;
+
 /**
  * https://picocli.info/#_use_case_configure_log_level_with_a_global_option
  */
@@ -23,7 +26,8 @@ public class Verbosity {
     private int level = 0;
 
     public static void setLoggingLevel(Level level) {
-        Configurator.setRootLevel(level);
+        LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
+        context.getLogger(ROOT_LOGGER_NAME).setLevel(level);
     }
 
     public static void disable() {

clusterless-main/src/main/java/clusterless/cls/Main.java

@@ -30,9 +30,8 @@
 import clusterless.cls.util.ExitCodeExceptionMapper;
 import clusterless.cls.util.ParameterExceptionHandler;
 import clusterless.cls.util.VersionProvider;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.jetbrains.annotations.NotNull;
+import org.slf4j.LoggerFactory;
 import picocli.CommandLine;
 
 import java.io.IOException;
@@ -64,7 +63,7 @@
         }
 )
 public class Main extends Startup implements Callable<Integer> {
-    private static final Logger LOG = LogManager.getLogger(Main.class);
+    private static final org.slf4j.Logger LOG = LoggerFactory.getLogger(Main.class);
 
     /**
      * This provides a global --providers predicate, but when calling a provider, we need to sort out a way

clusterless-main/src/main/resources/logback.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE configuration>
+
+<configuration>
+
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <!-- encoders are assigned the type
+             ch.qos.logback.classic.encoder.PatternLayoutEncoder by default -->
+        <encoder>
+            <pattern>%yellow(%d{HH:mm:ss.SSS}) %highlight(%-5level){FATAL=bg_red, ERROR=red, WARN=yellow, INFO=green}
+                %msg%n
+            </pattern>
+        </encoder>
+    </appender>
+
+    <root level="info">
+        <appender-ref ref="STDOUT"/>
+    </root>
+</configuration>

clusterless-model/src/main/java/clusterless/cls/managed/component/ComponentServices.java

@@ -14,16 +14,15 @@
 import clusterless.cls.model.deploy.Deployable;
 import clusterless.cls.model.deploy.Extensible;
 import clusterless.cls.util.Annotations;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.util.*;
 
 /**
  *
  */
 public class ComponentServices {
-    private static final Logger LOG = LogManager.getLogger(ComponentServices.class);
+    private static final org.slf4j.Logger LOG = LoggerFactory.getLogger(ComponentServices.class);
 
     public static final ComponentServices INSTANCE = new ComponentServices();
 

clusterless-model/src/main/java/clusterless/cls/managed/dataset/DatasetResolver.java

@@ -11,9 +11,8 @@
 import clusterless.cls.model.deploy.*;
 import com.google.common.collect.ArrayListMultimap;
 import com.google.common.collect.Multimap;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.jetbrains.annotations.NotNull;
+import org.slf4j.LoggerFactory;
 
 import java.util.*;
 import java.util.stream.Collectors;
@@ -26,7 +25,7 @@
  * to declare read permissions against datasets they do not own.
  */
 public class DatasetResolver {
-    private static final Logger LOG = LogManager.getLogger(DatasetResolver.class);
+    private static final org.slf4j.Logger LOG = LoggerFactory.getLogger(DatasetResolver.class);
     private final List<Deployable> deployables;
     private final Map<Placement, Map<ReferencedDataset, OwnedDataset>> resolved = new HashMap<>();
     private final RemoteDatasetOwnerLookup remoteLookup;

clusterless-scenario/build.gradle.kts

@@ -64,7 +64,7 @@ dependencies {
 
     implementation("javax.validation:validation-api:2.0.1.Final")
 
-    val springBoot = "2.7.3"
+    val springBoot = "2.7.18"
     implementation("org.springframework.boot:spring-boot-starter:$springBoot") {
         exclude("org.springframework.boot", "spring-boot-starter-logging")
     }
@@ -73,13 +73,25 @@ dependencies {
     implementation("org.springframework.boot:spring-boot-starter-actuator:$springBoot")
     implementation("org.springframework.retry:spring-retry:1.3.3") // 2.0.1 is on jdk 17
 
-    implementation("org.apache.logging.log4j:log4j-web")
-
     runtimeOnly("org.glassfish.jaxb:jaxb-runtime:2.3.3")
 
     implementation("com.google.guava:guava")
 }
 
+// the current version of spring boot, used by conductor, hard codes a dependency on
+// org.slf4j.impl.StaticLoggerBinder in the LogbackLoggingSystem class.
+// this was removed in recent slf4j/logback releases so we must pin the scenario project
+// to older versions of slf4j/logback
+configurations.all {
+    resolutionStrategy {
+        force(
+            "org.slf4j:slf4j-api:1.7.28",
+            "ch.qos.logback:logback-classic:1.2.11",
+            "ch.qos.logback:logback-core:1.2.11"
+        )
+    }
+}
+
 application {
     applicationName = "cls-scenario"
     mainClass.set("clusterless.scenario.Main")

clusterless-scenario/src/main/java/clusterless/scenario/Main.java

@@ -17,9 +17,9 @@
 import clusterless.scenario.model.Scenario;
 import com.netflix.conductor.common.metadata.tasks.Task;
 import com.netflix.conductor.common.run.Workflow;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.jetbrains.annotations.NotNull;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.springframework.context.ConfigurableApplicationContext;
 import picocli.CommandLine;
 
@@ -43,7 +43,7 @@
         }
 )
 public class Main implements Callable<Integer> {
-    private static final Logger LOG = LogManager.getLogger(Main.class);
+    private static final Logger LOG = LoggerFactory.getLogger(Main.class);
 
     private ConfigurableApplicationContext server;
 

clusterless-scenario/src/main/java/clusterless/scenario/conductor/ConductorApp.java

@@ -8,8 +8,8 @@
 
 package clusterless.scenario.conductor;
 
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
@@ -19,7 +19,7 @@
 @SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
 @ComponentScan(basePackages = {"com.netflix.conductor", "io.orkes.conductor"})
 public class ConductorApp {
-    private static final Logger LOG = LogManager.getLogger(ConductorApp.class);
+    private static final Logger LOG = LoggerFactory.getLogger(ConductorApp.class);
 
     public static ConfigurableApplicationContext run(String... args) {
         LOG.info("Starting Conductor");

clusterless-scenario/src/main/java/clusterless/scenario/conductor/runner/BootstrapRunner.java

@@ -15,17 +15,17 @@
 import com.netflix.conductor.common.metadata.workflow.StartWorkflowRequest;
 import com.netflix.conductor.common.metadata.workflow.WorkflowDef;
 import com.netflix.conductor.common.metadata.workflow.WorkflowTask;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.jetbrains.annotations.NotNull;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.nio.file.Path;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 
 public class BootstrapRunner {
-    private static final Logger LOG = LogManager.getLogger(BootstrapRunner.class);
+    private static final Logger LOG = LoggerFactory.getLogger(BootstrapRunner.class);
     private final Options options;
     private final WorkflowManager workflowManager;
     private final Map<String, String> placement;

clusterless-scenario/src/main/java/clusterless/scenario/conductor/runner/ScenarioRunner.java

@@ -24,17 +24,17 @@
 import com.netflix.conductor.common.metadata.workflow.WorkflowDef;
 import com.netflix.conductor.common.metadata.workflow.WorkflowTask;
 import com.netflix.conductor.sdk.workflow.def.tasks.*;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.jetbrains.annotations.NotNull;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.time.Duration;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 
 public class ScenarioRunner {
-    private static final Logger LOG = LogManager.getLogger(ScenarioRunner.class);
+    private static final Logger LOG = LoggerFactory.getLogger(ScenarioRunner.class);
     private final Options options;
     private final WorkflowManager workflowManager;
     private final Scenario scenario;