Building ClientCache Applications

1. Building ClientCache Applications

The first, opinionated option provided to you by Spring Boot for Apache Geode & Pivotal GemFire (SBDG) out-of-the-box is a {apache-geode-javadoc}/org/apache/geode/cache/client/ClientCache.html[ClientCache] instance, simply by declaring either Spring Boot for Apache Geode or Spring Boot for Pivotal GemFire on your application classpath.

It is assumed that most application developers using Spring Boot to build applications backed by either Apache Geode or Pivotal GemFire will be building cache client applications deployed in an Apache Geode or Pivotal GemFire {apache-geode-docs}/topologies_and_comm/cs_configuration/chapter_overview.html[Client/Server topology]. A client/server topology is the most common and traditional architecture employed by enterprise applications.

For example, you can begin building a Spring Boot, Apache Geode or Pivotal GemFire, ClientCache application with either the spring-geode-starter or spring-gemfire-starter on your application’s classpath:

Spring Boot for Apache Geode on the application classpath

<dependency>
  <groupId>org.springframework.geode</groupId>
  <artifactId>spring-geode-starter</artifactId>
</dependency>

Then, you configure and bootstrap your Spring Boot, Apache Geode ClientCache application with the following main application class:

Spring Boot, Apache Geode ClientCache Application

@SpringBootApplication
public class SpringBootApacheGeodeClientCacheApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootApacheGeodeClientCacheApplication.class, args);
    }
}

Your application now has a ClientCache instance, which is able to connect to an Apache Geode or Pivotal GemFire server running on localhost, listening on the default CacheServer port, 40404.

By default, an Apache Geode or Pivotal GemFire server (i.e. CacheServer) must be running in order to use the ClientCache instance. However, it is perfectly valid to create a ClientCache instance and perform data access operations using LOCAL Regions. This is very useful during development.

To develop with LOCAL Regions, you only need to define your cache Regions with the {apache-geode-javadoc}/org/apache/geode/cache/client/ClientRegionShortcut.html#LOCAL[ClientRegionShortcut.LOCAL] data management policy.

When you are ready to switch from your local development environment (IDE) to a client/server architecture in a managed environment, you simply change the data management policy of the client Region from LOCAL back to the default PROXY, or even a CACHING_PROXY, data management policy which will cause the data to be sent/received to and from 1 or more servers, respectively.

Compare and contrast the above configuration with Spring Data for Apache Geode/Pivotal GemFire’s {spring-data-geode-docs-html}/#bootstrap-annotation-config-geode-applications[approach].

It is uncommon to ever need a direct reference to the ClientCache instance provided by SBDG injected into your application components (e.g. @Service or @Repository beans defined in a Spring ApplicationContext) whether you are configuring additional GemFire/Geode objects (e.g. Regions, Indexes, etc) or simply using those objects indirectly in your applications. However, it is also possible to do so if and when needed.

For example, perhaps you want to perform some additional ClientCache initialization in a Spring Boot {spring-boot-javadoc}/org/springframework/boot/ApplicationRunner.html[ApplicationRunner] on startup:

Injecting a GemFireCache reference

@SpringBootApplication
public class SpringBootApacheGeodeClientCacheApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootApacheGeodeClientCacheApplication.class, args);
    }

    @Bean
    ApplicationRunner runAdditionalClientCacheInitialization(GemFireCache gemfireCache) {

        return args -> {

            ClientCache clientCache = (ClientCache) gemfireCache;

            // perform additional ClientCache initialization as needed
        };
    }
}

1.1. Building Embedded (Peer & Server) Cache Applications

What if you want to build an embedded, peer Cache application instead?

Perhaps you need an actual peer cache member, configured and bootstrapped with Spring Boot, along with the ability to join this member to a (possibly) existing cluster (of data servers) as a peer. Well, you can do that too.

Remember the 2nd goal in Spring Boot’s {spring-boot-docs-html}/#getting-started-introducing-spring-boot[documentation]:

Be opinionated out of the box but get out of the way quickly as requirements start to diverge from the defaults.

It is the 2nd part, "get out of the way quickly as requirements start to diverge from the defaults" that I refer to here.

If your application requirements demand you use Spring Boot to configure and bootstrap an embedded, peer Cache Apache Geode or Pivotal GemFire application, then simply declare your intentions with either SDG’s {spring-data-geode-javadoc}/org/springframework/data/gemfire/config/annotation/PeerCacheApplication.html[@PeerCacheApplication] annotation, or alternatively, if you need to enable connections from ClientCache apps as well, use the SDG {spring-data-geode-javadoc}/org/springframework/data/gemfire/config/annotation/CacheServerApplication.html[@CacheServerApplication] annotation:

Spring Boot, Apache Geode/Pivotal GemFire CacheServer Application

@SpringBootApplication
@CacheServerApplication(name = "MySpringBootApacheGeodeCacheServerApplication")
public class SpringBootApacheGeodeCacheServerApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootApacheGeodeCacheServerApplication.class, args);
    }
}

An Apache Geode/Pivotal GemFire "server" is not necessarily a “CacheServer” capable of serving cache clients. It is merely a peer member in the GemFire/Geode cluster (a.k.a. distributed system) that stores and manages data.

By explicitly declaring the @CacheServerApplication annotation, you are telling Spring Boot that you do not want the default, ClientCache instance, but rather an embedded, peer Cache instance with a CacheServer component, which enables connections from ClientCache apps.

You can also enable 2 other GemFire/Geode services, an embedded Locator, which allows clients or even other peers to "locate" servers in a cluster, as well as an embedded Manager, which allows the GemFire/Geode application process to be managed and monitored using {apache-geode-docs}/tools_modules/gfsh/chapter_overview.html[Gfsh], GemFire/Geode’s shell tool:

Spring Boot, Apache Geode/Pivotal GemFire CacheServer Application with Locator and Manager services enabled

@SpringBootApplication
@CacheServerApplication(name = "SpringBootApacheGeodeCacheServerApplication")
@EnableLocator
@EnableManager
public class SpringBootApacheGeodeCacheServerApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootApacheGeodeCacheServerApplication.class, args);
    }
}

Then, you can use Gfsh to connect to and manage this server:

$ echo $GEMFIRE
/Users/jblum/pivdev/apache-geode-1.2.1

$ gfsh
    _________________________     __
   / _____/ ______/ ______/ /____/ /
  / /  __/ /___  /_____  / _____  /
 / /__/ / ____/  _____/ / /    / /
/______/_/      /______/_/    /_/    1.2.1

Monitor and Manage Apache Geode

gfsh>connect
Connecting to Locator at [host=localhost, port=10334] ..
Connecting to Manager at [host=10.0.0.121, port=1099] ..
Successfully connected to: [host=10.0.0.121, port=1099]


gfsh>list members
                   Name                     | Id
------------------------------------------- | --------------------------------------------------------------------------
SpringBootApacheGeodeCacheServerApplication | 10.0.0.121(SpringBootApacheGeodeCacheServerApplication:29798)<ec><v0>:1024

gfsh>
gfsh>describe member --name=SpringBootApacheGeodeCacheServerApplication
Name        : SpringBootApacheGeodeCacheServerApplication
Id          : 10.0.0.121(SpringBootApacheGeodeCacheServerApplication:29798)<ec><v0>:1024
Host        : 10.0.0.121
Regions     :
PID         : 29798
Groups      :
Used Heap   : 168M
Max Heap    : 3641M
Working Dir : /Users/jblum/pivdev/spring-boot-data-geode/spring-geode-docs/build
Log file    : /Users/jblum/pivdev/spring-boot-data-geode/spring-geode-docs/build
Locators    : localhost[10334]

Cache Server Information
Server Bind              :
Server Port              : 40404
Running                  : true
Client Connections       : 0

You can even start additional servers in Gfsh, which will connect to your Spring Boot configured and bootstrapped Apache Geode or Pivotal GemFire CacheServer application. These additional servers started in Gfsh know about the Spring Boot, GemFire/Geode server because of the embedded Locator service, which is running on localhost, listening on the default Locator port, 10334:

gfsh>start server --name=GfshServer --log-level=config --disable-default-server
Starting a Geode Server in /Users/jblum/pivdev/lab/GfshServer...
...
Server in /Users/jblum/pivdev/lab/GfshServer on 10.0.0.121 as GfshServer is currently online.
Process ID: 30031
Uptime: 3 seconds
Geode Version: 1.2.1
Java Version: 1.8.0_152
Log File: /Users/jblum/pivdev/lab/GfshServer/GfshServer.log
JVM Arguments: -Dgemfire.default.locators=10.0.0.121:127.0.0.1[10334] -Dgemfire.use-cluster-configuration=true -Dgemfire.start-dev-rest-api=false -Dgemfire.log-level=config -XX:OnOutOfMemoryError=kill -KILL %p -Dgemfire.launcher.registerSignalHandlers=true -Djava.awt.headless=true -Dsun.rmi.dgc.server.gcInterval=9223372036854775806
Class-Path: /Users/jblum/pivdev/apache-geode-1.2.1/lib/geode-core-1.2.1.jar:/Users/jblum/pivdev/apache-geode-1.2.1/lib/geode-dependencies.jar


gfsh>list members
                   Name                     | Id
------------------------------------------- | --------------------------------------------------------------------------
SpringBootApacheGeodeCacheServerApplication | 10.0.0.121(SpringBootApacheGeodeCacheServerApplication:29798)<ec><v0>:1024
GfshServer                                  | 10.0.0.121(GfshServer:30031)<v1>:1025

Perhaps you want to start the other way around. As developer, I may need to connect my Spring Boot configured and bootstrapped GemFire/Geode server application to an existing cluster. You can start the cluster in Gfsh by executing the following commands:

gfsh>start locator --name=GfshLocator --port=11235 --log-level=config
Starting a Geode Locator in /Users/jblum/pivdev/lab/GfshLocator...
...
Locator in /Users/jblum/pivdev/lab/GfshLocator on 10.0.0.121[11235] as GfshLocator is currently online.
Process ID: 30245
Uptime: 3 seconds
Geode Version: 1.2.1
Java Version: 1.8.0_152
Log File: /Users/jblum/pivdev/lab/GfshLocator/GfshLocator.log
JVM Arguments: -Dgemfire.log-level=config -Dgemfire.enable-cluster-configuration=true -Dgemfire.load-cluster-configuration-from-dir=false -Dgemfire.launcher.registerSignalHandlers=true -Djava.awt.headless=true -Dsun.rmi.dgc.server.gcInterval=9223372036854775806
Class-Path: /Users/jblum/pivdev/apache-geode-1.2.1/lib/geode-core-1.2.1.jar:/Users/jblum/pivdev/apache-geode-1.2.1/lib/geode-dependencies.jar

Successfully connected to: JMX Manager [host=10.0.0.121, port=1099]

Cluster configuration service is up and running.


gfsh>start server --name=GfshServer --log-level=config --disable-default-server
Starting a Geode Server in /Users/jblum/pivdev/lab/GfshServer...
....
Server in /Users/jblum/pivdev/lab/GfshServer on 10.0.0.121 as GfshServer is currently online.
Process ID: 30270
Uptime: 4 seconds
Geode Version: 1.2.1
Java Version: 1.8.0_152
Log File: /Users/jblum/pivdev/lab/GfshServer/GfshServer.log
JVM Arguments: -Dgemfire.default.locators=10.0.0.121[11235] -Dgemfire.use-cluster-configuration=true -Dgemfire.start-dev-rest-api=false -Dgemfire.log-level=config -XX:OnOutOfMemoryError=kill -KILL %p -Dgemfire.launcher.registerSignalHandlers=true -Djava.awt.headless=true -Dsun.rmi.dgc.server.gcInterval=9223372036854775806
Class-Path: /Users/jblum/pivdev/apache-geode-1.2.1/lib/geode-core-1.2.1.jar:/Users/jblum/pivdev/apache-geode-1.2.1/lib/geode-dependencies.jar


gfsh>list members
   Name     | Id
----------- | --------------------------------------------------
GfshLocator | 10.0.0.121(GfshLocator:30245:locator)<ec><v0>:1024
GfshServer  | 10.0.0.121(GfshServer:30270)<v1>:1025

Then, modify the SpringBootApacheGeodeCacheServerApplication class to connect to the existing cluster, like so:

Spring Boot, Apache Geode/Pivotal GemFire CacheServer Application with Locator and Manager services enabled

@SpringBootApplication
@CacheServerApplication(name = "MySpringBootApacheGeodeCacheServerApplication", locators = "localhost[11235]")
public class SpringBootApacheGeodeCacheServerApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootApacheGeodeClientCacheApplication.class, args);
    }
}

Notice I configured the SpringBootApacheGeodeCacheServerApplication class, @CacheServerApplication annotation, locators property with the host and port (i.e. "localhost[11235]") on which I started my Locator using Gfsh.

After running your Spring Boot, Apache Geode CacheServer application again, and then running list members in Gfsh, you should see:

gfsh>list members
                   Name                     | Id
------------------------------------------- | ----------------------------------------------------------------------
GfshLocator                                 | 10.0.0.121(GfshLocator:30245:locator)<ec><v0>:1024
GfshServer                                  | 10.0.0.121(GfshServer:30270)<v1>:1025
SpringBootApacheGeodeCacheServerApplication | 10.0.0.121(SpringBootApacheGeodeCacheServerApplication:30279)<v2>:1026


gfsh>describe member --name=SpringBootApacheGeodeCacheServerApplication
Name        : SpringBootApacheGeodeCacheServerApplication
Id          : 10.0.0.121(SpringBootApacheGeodeCacheServerApplication:30279)<v2>:1026
Host        : 10.0.0.121
Regions     :
PID         : 30279
Groups      :
Used Heap   : 165M
Max Heap    : 3641M
Working Dir : /Users/jblum/pivdev/spring-boot-data-geode/spring-geode-docs/build
Log file    : /Users/jblum/pivdev/spring-boot-data-geode/spring-geode-docs/build
Locators    : localhost[11235]

Cache Server Information
Server Bind              :
Server Port              : 40404
Running                  : true
Client Connections       : 0

In both scenarios, the Spring Boot configured and bootstrapped Apache Geode (or Pivotal GemFire) server and the Gfsh Locator and Server formed a cluster.

While you can use either approach and Spring does not care, it is far more convenient to use Spring Boot and your IDE to form a small cluster while developing. By leveraging Spring profiles, it is far simpler and much faster to configure and start a small cluster.

Plus, this is useful for rapidly prototyping, testing and debugging your entire, end-to-end application and system architecture, all right from the comfort and familiarity of your IDE of choice. No additional tooling (e.g. Gfsh) or knowledge is required to get started quickly and easily.

Just build and run it!

Be careful to vary your port numbers for the embedded services, like the CacheServer, Locators and Manager, especially if you start multiple instances, otherwise you will run into a java.net.BindException due to port conflicts.

See the Appendix, [geode-cluster-configuration-bootstrapping] for more details.

1.2. Building Locator Applications

In addition to ClientCache, CacheServer and peer Cache applications, SDG, and by extension SBDG, now supports Locator-based, Spring Boot applications.

An Apache Geode or Pivotal GemFire Locator is a location-based service, or alternatively and more typically, a standalone process enabling clients to "locate" a cluster of Apache Geode/Pivotal GemFire servers to manage data. Many cache clients can connect to the same cluster in order to share data. Running multiple clients is common in a Microservices architecture where you need to scale-up the number of app instances to satisfy the demand.

A Locator is also used by joining members of an existing cluster to scale-out and increase capacity of the logically pooled system resources (i.e. Memory, CPU and Disk). A Locator maintains metadata that is sent to the clients to enable capabilities like single-hop data access, routing data access operations to the data node in the cluster maintaining the data of interests. A Locator also maintains load information for servers in the cluster, which enables the load to be uniformly distributed across the cluster while also providing fail-over services to a redundant member if the primary fails. A Locator provides many more benefit and you are encouraged to read the {apache-geode-docs}/configuring/running/running_the_locator.html[documentation] for more details.

As shown above, a Locator service can be embedded in either a peer Cache or CacheServer, Spring Boot application using the SDG @EnableLocator annotation:

Embedded Locator Service

@EnableLocator
@CacheServerApplication
@SpringBootApplication
class SpringBootCacheServerWithEmbeddedLocatorApplication { /* ... */ }

However, it is more common to start standalone Locator JVM processes. This is useful when you want to increase the resiliency of your cluster in face of network and process failures, which are bound to happen. If a Locator JVM process crashes or gets severed from the cluster due to a network failure, then having multiple Locators provides a higher degree of availability (HA) through redundancy.

Not to worry though, if all Locators in the cluster go down, then the cluster will still remain intact. You simply won’t be able to add more peer members (i.e. scale-up the number of data nodes in the cluster) or connect additional clients. If all the Locators in the cluster go down, then it is safe to simply restart them after a thorough diagnosis.

Once a client receives metadata about the cluster of servers, then all data access operations are sent directly to servers in the cluster, not a Locator. Therefore, existing, connected clients will remain connected and operable.

To configure and bootstrap Locator-based, Spring Boot applications as standalone JVM processes, use the following configuration:

Standalone Locator Process

@LocatorApplication
@SpringBootApplication
class SpringBootApacheGeodeLocatorApplication { /* ... */ }

Instead of using the @EnableLocator annotation, you now use the @LocatorApplication annotation.

The @LocatorApplication annotation works in the same way as the @PeerCacheApplication and @CacheServerApplication annotations, bootstrapping a Apache Geode or Pivotal GemFire process and overriding the default ClientCache instance provided by SBDG out-of-the-box.

If your @SpringBootApplication class is annotated with @LocatorApplication, then it can only be a Locator and not a ClientCache, CacheServer or peer Cache application.

With our Spring Boot, Apache Geode Locator application, we can connect both Spring Boot configured and bootstrapped peer members (peer Cache, CacheServer and Locator applications) as well as Gfsh started Locators and Servers.

First, let’s startup 2 Locators using our Apache Geode Locator, Spring Boot application class.

SpringBootApacheGeodeLocatorApplication class

@UseLocators
@SpringBootApplication
@LocatorApplication(name = "SpringBootApacheGeodeLocatorApplication")
public class SpringBootApacheGeodeLocatorApplication {

	public static void main(String[] args) {

		new SpringApplicationBuilder(SpringBootApacheGeodeLocatorApplication.class)
			.web(WebApplicationType.NONE)
			.build()
			.run(args);

		System.err.println("Press <enter> to exit!");

		new Scanner(System.in).nextLine();
	}

	@Configuration
	@EnableManager(start = true)
	@Profile("manager")
	@SuppressWarnings("unused")
	static class ManagerConfiguration { }

}

We also need to vary the configuration for each Locator app instance.

Apache Geode and Pivotal GemFire requires each peer member in the cluster to be uniquely named. We can set the name of the Locator by using the spring.data.gemfire.locator.name SDG property set as a JVM System Property in your IDE’s Run Configuration Profile for the application main class like so: --Dspring.data.gemfire.locator.name=SpringLocatorOne. We name the second Locator app instance, "SpringLocatorTwo".

Additionally, we must vary the port numbers that the Locators use to listen for connections. By default, an Apache Geode or Pivotal GemFire Locator listens on port 10334. We can set the Locator port using the spring.data.gemfire.locator.port SDG property.

For our first Locator app instance (i.e. "SpringLocatorOne"), we also enable the "manager" Profile so that we can connect to the Locator using Gfsh.

Our IDE Run Configuration Profile for our first Locator app instance appears as:

-server -ea -Dspring.profiles.active=manager -Dspring.data.gemfire.locator.name=SpringLocatorOne -Dlogback.log.level=INFO

And our IDE Run Configuration Profile for our second Locator app instance appears as:

-server -ea -Dspring.profiles.active= -Dspring.data.gemfire.locator.name=SpringLocatorTwo -Dspring.data.gemfire.locator.port=11235 -Dlogback.log.level=INFO

You should see log output similar to the following when you start a Locator app instance:

Spring Boot, Apache Geode Locator log output

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::  (v2.2.0.BUILD-SNAPSHOT)

2019-09-01 11:02:48,707  INFO .SpringBootApacheGeodeLocatorApplication:  55 - Starting SpringBootApacheGeodeLocatorApplication on jblum-mbpro-2.local with PID 30077 (/Users/jblum/pivdev/spring-boot-data-geode/spring-geode-docs/out/production/classes started by jblum in /Users/jblum/pivdev/spring-boot-data-geode/spring-geode-docs/build)
2019-09-01 11:02:48,711  INFO .SpringBootApacheGeodeLocatorApplication: 651 - No active profile set, falling back to default profiles: default
2019-09-01 11:02:49,374  INFO xt.annotation.ConfigurationClassEnhancer: 355 - @Bean method LocatorApplicationConfiguration.exclusiveLocatorApplicationBeanFactoryPostProcessor is non-static and returns an object assignable to Spring's BeanFactoryPostProcessor interface. This will result in a failure to process annotations such as @Autowired, @Resource and @PostConstruct within the method's declaring @Configuration class. Add the 'static' modifier to this method to avoid these container lifecycle issues; see @Bean javadoc for complete details.
2019-09-01 11:02:49,919  INFO ode.distributed.internal.InternalLocator: 530 - Starting peer location for Distribution Locator on 10.99.199.24[11235]
2019-09-01 11:02:49,925  INFO ode.distributed.internal.InternalLocator: 498 - Starting Distribution Locator on 10.99.199.24[11235]
2019-09-01 11:02:49,926  INFO distributed.internal.tcpserver.TcpServer: 242 - Locator was created at Sun Sep 01 11:02:49 PDT 2019
2019-09-01 11:02:49,927  INFO distributed.internal.tcpserver.TcpServer: 243 - Listening on port 11235 bound on address 0.0.0.0/0.0.0.0
2019-09-01 11:02:49,928  INFO ternal.membership.gms.locator.GMSLocator: 162 - GemFire peer location service starting.  Other locators: localhost[10334]  Locators preferred as coordinators: true  Network partition detection enabled: true  View persistence file: /Users/jblum/pivdev/spring-boot-data-geode/spring-geode-docs/build/locator11235view.dat
2019-09-01 11:02:49,928  INFO ternal.membership.gms.locator.GMSLocator: 416 - Peer locator attempting to recover from localhost/127.0.0.1:10334
2019-09-01 11:02:49,963  INFO ternal.membership.gms.locator.GMSLocator: 422 - Peer locator recovered initial membership of View[10.99.199.24(SpringLocatorOne:30043:locator)<ec><v0>:41000|0] members: [10.99.199.24(SpringLocatorOne:30043:locator)<ec><v0>:41000]
2019-09-01 11:02:49,963  INFO ternal.membership.gms.locator.GMSLocator: 407 - Peer locator recovered state from LocatorAddress [socketInetAddress=localhost/127.0.0.1:10334, hostname=localhost, isIpString=false]
2019-09-01 11:02:49,965  INFO ode.distributed.internal.InternalLocator: 644 - Starting distributed system
2019-09-01 11:02:50,007  INFO he.geode.internal.logging.LoggingSession:  82 -
---------------------------------------------------------------------------

  Licensed to the Apache Software Foundation (ASF) under one or more
  contributor license agreements.  See the NOTICE file distributed with this
  work for additional information regarding copyright ownership.

  The ASF licenses this file to You under the Apache License, Version 2.0
  (the "License"); you may not use this file except in compliance with the
  License.  You may obtain a copy of the License at

  https://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
  License for the specific language governing permissions and limitations
  under the License.

---------------------------------------------------------------------------
Build-Date: 2019-04-19 11:49:13 -0700
Build-Id: onichols 0
Build-Java-Version: 1.8.0_192
Build-Platform: Mac OS X 10.14.4 x86_64
Product-Name: Apache Geode
Product-Version: 1.9.0
Source-Date: 2019-04-19 11:11:31 -0700
Source-Repository: release/1.9.0
Source-Revision: c0a73d1cb84986d432003bd12e70175520e63597
Native version: native code unavailable
Running on: 10.99.199.24/10.99.199.24, 8 cpu(s), x86_64 Mac OS X 10.13.6
Communications version: 100
Process ID: 30077
User: jblum
Current dir: /Users/jblum/pivdev/spring-boot-data-geode/spring-geode-docs/build
Home dir: /Users/jblum
Command Line Parameters:
  -ea
  -Dspring.profiles.active=
  -Dspring.data.gemfire.locator.name=SpringLocatorTwo
  -Dspring.data.gemfire.locator.port=11235
  -Dlogback.log.level=INFO
  -javaagent:/Applications/IntelliJ IDEA 19 CE.app/Contents/lib/idea_rt.jar=51961:/Applications/IntelliJ IDEA 19 CE.app/Contents/bin
  -Dfile.encoding=UTF-8
Class Path:
...
..
.
2019-09-01 11:02:54,112  INFO ode.distributed.internal.InternalLocator: 661 - Locator started on 10.99.199.24[11235]
2019-09-01 11:02:54,113  INFO ode.distributed.internal.InternalLocator: 769 - Starting server location for Distribution Locator on 10.99.199.24[11235]
2019-09-01 11:02:54,134  INFO nt.internal.locator.wan.LocatorDiscovery: 138 - Locator discovery task exchanged locator information 10.99.199.24[11235] with localhost[10334]: {-1=[10.99.199.24[10334]]}.
2019-09-01 11:02:54,242  INFO .SpringBootApacheGeodeLocatorApplication:  61 - Started SpringBootApacheGeodeLocatorApplication in 6.137470354 seconds (JVM running for 6.667)
Press <enter> to exit!

Next, start up the second Locator app instance (you should see log output similar to above). Then, connect to the cluster of Locators using Gfsh:

Cluster of Locators

$ echo $GEMFIRE
/Users/jblum/pivdev/apache-geode-1.9.0

$ gfsh
    _________________________     __
   / _____/ ______/ ______/ /____/ /
  / /  __/ /___  /_____  / _____  /
 / /__/ / ____/  _____/ / /    / /
/______/_/      /______/_/    /_/    1.9.0

Monitor and Manage Apache Geode

gfsh>connect
Connecting to Locator at [host=localhost, port=10334] ..
Connecting to Manager at [host=10.99.199.24, port=1099] ..
Successfully connected to: [host=10.99.199.24, port=1099]

gfsh>list members
      Name       | Id
---------------- | ------------------------------------------------------------------------
SpringLocatorOne | 10.99.199.24(SpringLocatorOne:30043:locator)<ec><v0>:41000 [Coordinator]
SpringLocatorTwo | 10.99.199.24(SpringLocatorTwo:30077:locator)<ec><v1>:41001

Using our SpringBootApacheGeodeCacheServerApplication main class from the previous section, we can configure and bootstrap an Apache Geode CacheServer application with Spring Boot and connect it to our cluster of Locators.

SpringBootApacheGeodeCacheServerApplication class

@SpringBootApplication
@CacheServerApplication(name = "SpringBootApacheGeodeCacheServerApplication")
@SuppressWarnings("unused")
public class SpringBootApacheGeodeCacheServerApplication {

	public static void main(String[] args) {

		new SpringApplicationBuilder(SpringBootApacheGeodeCacheServerApplication.class)
			.web(WebApplicationType.NONE)
			.build()
			.run(args);
	}

	@Configuration
	@UseLocators
	@Profile("clustered")
	static class ClusteredConfiguration { }

	@Configuration
	@EnableLocator
	@EnableManager(start = true)
	@Profile("!clustered")
	static class LonerConfiguration { }

}

Simply enable the "clustered" Profile by using a IDE Run Configuration similar to:

-server -ea -Dspring.profiles.active=clustered -Dspring.data.gemfire.name=SpringServer -Dspring.data.gemfire.cache.server.port=41414 -Dlogback.log.level=INFO

After the server starts up, you should see the new peer member in the cluster:

Cluster with Spring Boot configured and bootstrapped Apache Geode CacheServer

gfsh>list members
      Name       | Id
---------------- | ------------------------------------------------------------------------
SpringLocatorOne | 10.99.199.24(SpringLocatorOne:30043:locator)<ec><v0>:41000 [Coordinator]
SpringLocatorTwo | 10.99.199.24(SpringLocatorTwo:30077:locator)<ec><v1>:41001
SpringServer     | 10.99.199.24(SpringServer:30216)<v2>:41002

Finally, we can even start additional Locators and Servers connected to this cluster using Gfsh:

Gfsh started Locators and Servers

gfsh>start locator --name=GfshLocator --port=12345 --log-level=config
Starting a Geode Locator in /Users/jblum/pivdev/lab/GfshLocator...
......
Locator in /Users/jblum/pivdev/lab/GfshLocator on 10.99.199.24[12345] as GfshLocator is currently online.
Process ID: 30259
Uptime: 5 seconds
Geode Version: 1.9.0
Java Version: 1.8.0_192
Log File: /Users/jblum/pivdev/lab/GfshLocator/GfshLocator.log
JVM Arguments: -Dgemfire.default.locators=10.99.199.24[11235],10.99.199.24[10334] -Dgemfire.enable-cluster-configuration=true -Dgemfire.load-cluster-configuration-from-dir=false -Dgemfire.log-level=config -Dgemfire.launcher.registerSignalHandlers=true -Djava.awt.headless=true -Dsun.rmi.dgc.server.gcInterval=9223372036854775806
Class-Path: /Users/jblum/pivdev/apache-geode-1.9.0/lib/geode-core-1.9.0.jar:/Users/jblum/pivdev/apache-geode-1.9.0/lib/geode-dependencies.jar

gfsh>start server --name=GfshServer --server-port=45454 --log-level=config
Starting a Geode Server in /Users/jblum/pivdev/lab/GfshServer...
...
Server in /Users/jblum/pivdev/lab/GfshServer on 10.99.199.24[45454] as GfshServer is currently online.
Process ID: 30295
Uptime: 2 seconds
Geode Version: 1.9.0
Java Version: 1.8.0_192
Log File: /Users/jblum/pivdev/lab/GfshServer/GfshServer.log
JVM Arguments: -Dgemfire.default.locators=10.99.199.24[11235],10.99.199.24[12345],10.99.199.24[10334] -Dgemfire.start-dev-rest-api=false -Dgemfire.use-cluster-configuration=true -Dgemfire.log-level=config -XX:OnOutOfMemoryError=kill -KILL %p -Dgemfire.launcher.registerSignalHandlers=true -Djava.awt.headless=true -Dsun.rmi.dgc.server.gcInterval=9223372036854775806
Class-Path: /Users/jblum/pivdev/apache-geode-1.9.0/lib/geode-core-1.9.0.jar:/Users/jblum/pivdev/apache-geode-1.9.0/lib/geode-dependencies.jar

gfsh>list members
      Name       | Id
---------------- | ------------------------------------------------------------------------
SpringLocatorOne | 10.99.199.24(SpringLocatorOne:30043:locator)<ec><v0>:41000 [Coordinator]
SpringLocatorTwo | 10.99.199.24(SpringLocatorTwo:30077:locator)<ec><v1>:41001
SpringServer     | 10.99.199.24(SpringServer:30216)<v2>:41002
GfshLocator      | 10.99.199.24(GfshLocator:30259:locator)<ec><v3>:41003
GfshServer       | 10.99.199.24(GfshServer:30295)<v4>:41004

You simply must be careful to vary the ports is all and name your peer members appropriately. With Spring, and Spring Boot for Apache Geode or Pivotal GemFire (SBDG) in particular, it really is that easy!