Wait for database startup on boot

common/resources/common.properties

@@ -2,6 +2,7 @@ spring.datasource.url=${PANDAS_DB_URL:jdbc:h2:file:./data/db;AUTO_SERVER=true}
 spring.datasource.username=${PANDAS_DB_USER:pandas3}
 spring.datasource.password=${PANDAS_DB_PASSWORD:pandas3}
 spring.datasource.hikari.maximum-pool-size=15
+spring.datasource.hikari.initialization-fail-timeout=-1
 
 spring.h2.console = false
 
@@ -17,4 +18,5 @@ logging.level.org.hibernate.engine.transaction.jta.platform.internal.JtaPlatform
 logging.level.org.hibernate.jpa.internal.util.LogHelper=WARN
 logging.level.org.hibernate.orm.incubating=ERROR
 logging.level.org.springframework.data.repository.config.RepositoryConfigurationDelegate=WARN
+logging.level.org.springframework.jdbc.support.DatabaseStartupValidator=debug
 logging.level.org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean=WARN

common/src/pandas/core/DatabaseStartupConfig.java

@@ -0,0 +1,31 @@
+package pandas.core;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.autoconfigure.orm.jpa.EntityManagerFactoryDependsOnPostProcessor;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.jdbc.support.DatabaseStartupValidator;
+
+import javax.sql.DataSource;
+import java.util.concurrent.TimeUnit;
+
+@Configuration
+public class DatabaseStartupConfig {
+    @Bean
+    public DatabaseStartupValidator databaseStartupValidator(DataSource dataSource) {
+        var validator = new DatabaseStartupValidator();
+        validator.setDataSource(dataSource);
+        validator.setTimeout((int) TimeUnit.HOURS.toSeconds(4));
+        return validator;
+    }
+
+    /**
+     * This makes EntityManagerFactory depend on DatabaseStartupValidator to block startup
+     * until the database is ready.
+     */
+    @Bean
+    public static EntityManagerFactoryDependsOnPostProcessor databaseStartupDependency() {
+        return new EntityManagerFactoryDependsOnPostProcessor("databaseStartupValidator");
+    }
+}