Merge pull request #71 from evenh/startup-strategy

Configurable scheduler start

NOTICE

@@ -82,7 +82,9 @@ This software includes third party software subject to the following licenses:
   Spring Boot Actuator AutoConfigure under Apache License, Version 2.0
   Spring Boot Actuator Starter under Apache License, Version 2.0
   Spring Boot AOP Starter under Apache License, Version 2.0
+  Spring Boot Auto-Configure Annotation Processor under Apache License, Version 2.0
   Spring Boot AutoConfigure under Apache License, Version 2.0
+  Spring Boot Configuration Processor under Apache License, Version 2.0
   Spring Boot Data JPA Starter under Apache License, Version 2.0
   Spring Boot JDBC Starter under Apache License, Version 2.0
   Spring Boot Json Starter under Apache License, Version 2.0

README.md

@@ -180,7 +180,7 @@ For Spring Boot applications, there is a starter `db-scheduler-spring-boot-start
     <dependency>
         <groupId>com.github.kagkarlsson</groupId>
         <artifactId>db-scheduler-spring-boot-starter</artifactId>
-        <version>6.0</version>
+        <version>6.1</version>
     </dependency>
     ```
    **NOTE**: This includes the db-scheduler dependency itself.
@@ -202,6 +202,7 @@ db-scheduler.table-name=scheduled_tasks
 db-scheduler.immediate-execution-enabled=false
 db-scheduler.scheduler-name=
 db-scheduler.threads=10
+db-scheduler.delay-startup-until-context-ready=false
 ```
 
 

db-scheduler-boot-starter/pom.xml

@@ -53,6 +53,16 @@
             <artifactId>spring-boot-actuator-autoconfigure</artifactId>
             <optional>true</optional>
         </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-autoconfigure-processor</artifactId>
+            <optional>true</optional>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-configuration-processor</artifactId>
+            <optional>true</optional>
+        </dependency>
 
         <!-- Validation -->
         <dependency>
@@ -66,6 +76,13 @@
             <scope>provided</scope>
         </dependency>
 
+        <!-- Annotations -->
+        <dependency>
+            <groupId>javax.annotation</groupId>
+            <artifactId>javax.annotation-api</artifactId>
+            <scope>provided</scope>
+        </dependency>
+
         <!-- Test -->
         <dependency>
             <groupId>junit</groupId>

db-scheduler-boot-starter/src/main/java/com/github/kagkarlsson/scheduler/boot/autoconfigure/DbSchedulerAutoConfiguration.java

@@ -6,6 +6,9 @@
 import com.github.kagkarlsson.scheduler.boot.actuator.DbSchedulerHealthIndicator;
 import com.github.kagkarlsson.scheduler.boot.config.DbSchedulerCustomizer;
 import com.github.kagkarlsson.scheduler.boot.config.DbSchedulerProperties;
+import com.github.kagkarlsson.scheduler.boot.config.DbSchedulerStarter;
+import com.github.kagkarlsson.scheduler.boot.config.startup.ContextReadyStart;
+import com.github.kagkarlsson.scheduler.boot.config.startup.ImmediateStart;
 import com.github.kagkarlsson.scheduler.task.OnStartup;
 import com.github.kagkarlsson.scheduler.task.Task;
 import java.util.List;
@@ -62,7 +65,7 @@ public DbSchedulerCustomizer noopCustomizer() {
 
     @ConditionalOnBean(DataSource.class)
     @ConditionalOnMissingBean
-    @Bean(initMethod = "start", destroyMethod = "stop")
+    @Bean(destroyMethod = "stop")
     public Scheduler scheduler(DbSchedulerCustomizer customizer) {
         log.info("Creating db-scheduler using tasks from Spring context: {}", configuredTasks);
 
@@ -112,6 +115,16 @@ public HealthIndicator dbScheduler(Scheduler scheduler) {
         return new DbSchedulerHealthIndicator(scheduler);
     }
 
+    @ConditionalOnBean(Scheduler.class)
+    @Bean
+    public DbSchedulerStarter dbSchedulerStarter(Scheduler scheduler) {
+        if (config.isDelayStartupUntilContextReady()) {
+            return new ContextReadyStart(scheduler);
+        }
+
+        return new ImmediateStart(scheduler);
+    }
+
     private static DataSource configureDataSource(DataSource existingDataSource) {
         if (existingDataSource instanceof TransactionAwareDataSourceProxy) {
             log.debug("Using an already transaction aware DataSource");

db-scheduler-boot-starter/src/main/java/com/github/kagkarlsson/scheduler/boot/config/DbSchedulerProperties.java

@@ -68,6 +68,12 @@ public class DbSchedulerProperties {
      */
     private Optional<Integer> pollingLimit = Optional.empty();
 
+    /**
+     * <p>Whether to start the scheduler when the application context has been loaded or as soon as
+     * possible.
+     */
+    private boolean delayStartupUntilContextReady = false;
+
     public boolean isEnabled() {
         return enabled;
     }
@@ -131,4 +137,12 @@ public Optional<Integer> getPollingLimit() {
     public void setPollingLimit(final Optional<Integer> pollingLimit) {
         this.pollingLimit = pollingLimit;
     }
+
+    public boolean isDelayStartupUntilContextReady() {
+        return delayStartupUntilContextReady;
+    }
+
+    public void setDelayStartupUntilContextReady(final boolean delayStartupUntilContextReady) {
+        this.delayStartupUntilContextReady = delayStartupUntilContextReady;
+    }
 }

db-scheduler-boot-starter/src/main/java/com/github/kagkarlsson/scheduler/boot/config/DbSchedulerStarter.java

@@ -0,0 +1,5 @@
+package com.github.kagkarlsson.scheduler.boot.config;
+
+public interface DbSchedulerStarter {
+  void doStart();
+}

db-scheduler-boot-starter/src/main/java/com/github/kagkarlsson/scheduler/boot/config/startup/AbstractSchedulerStarter.java

@@ -0,0 +1,35 @@
+package com.github.kagkarlsson.scheduler.boot.config.startup;
+
+import com.github.kagkarlsson.scheduler.Scheduler;
+import com.github.kagkarlsson.scheduler.SchedulerState;
+import com.github.kagkarlsson.scheduler.boot.config.DbSchedulerStarter;
+import java.util.Objects;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public abstract class AbstractSchedulerStarter implements DbSchedulerStarter {
+  private final Logger log = LoggerFactory.getLogger(this.getClass());
+  private final Scheduler scheduler;
+
+  protected AbstractSchedulerStarter(Scheduler scheduler) {
+    this.scheduler = Objects.requireNonNull(scheduler, "A scheduler must be provided");
+  }
+
+  @Override
+  public void doStart() {
+    SchedulerState state = scheduler.getSchedulerState();
+
+    if (state.isShuttingDown()) {
+      log.warn("Scheduler is shutting down - will not attempting to start");
+      return;
+    }
+
+    if (state.isStarted()) {
+      log.info("Scheduler already started - will not attempt to start again");
+      return;
+    }
+
+    log.info("Triggering scheduler start");
+    scheduler.start();
+  }
+}

db-scheduler-boot-starter/src/main/java/com/github/kagkarlsson/scheduler/boot/config/startup/ContextReadyStart.java

@@ -0,0 +1,16 @@
+package com.github.kagkarlsson.scheduler.boot.config.startup;
+
+import com.github.kagkarlsson.scheduler.Scheduler;
+import org.springframework.context.event.ContextRefreshedEvent;
+import org.springframework.context.event.EventListener;
+
+public class ContextReadyStart extends AbstractSchedulerStarter {
+  public ContextReadyStart(Scheduler scheduler) {
+    super(scheduler);
+  }
+
+  @EventListener(ContextRefreshedEvent.class)
+  public void whenContextIsReady() {
+    doStart();
+  }
+}

db-scheduler-boot-starter/src/main/java/com/github/kagkarlsson/scheduler/boot/config/startup/ImmediateStart.java

@@ -0,0 +1,15 @@
+package com.github.kagkarlsson.scheduler.boot.config.startup;
+
+import com.github.kagkarlsson.scheduler.Scheduler;
+import javax.annotation.PostConstruct;
+
+public class ImmediateStart extends AbstractSchedulerStarter {
+  public ImmediateStart(final Scheduler scheduler) {
+    super(scheduler);
+  }
+
+  @PostConstruct
+  void startImmediately() {
+    doStart();
+  }
+}

pom.xml

@@ -377,6 +377,10 @@
 						<configuration>
 							<failOnWarning>true</failOnWarning>
 							<ignoreNonCompile>true</ignoreNonCompile>
+							<ignoredDependencies>
+								<ignoredDependency>org.springframework.boot:spring-boot-autoconfigure-processor</ignoredDependency>
+								<ignoredDependency>org.springframework.boot:spring-boot-configuration-processor</ignoredDependency>
+							</ignoredDependencies>
 						</configuration>
 					</execution>
 				</executions>