Hazelcast OSGi R7+ Distribution and Discovery Provider

ECF OSGi R7 Remote Services Distribution and Discovery Providers based upon Hazelcast.

ECF is an Eclipse Foundation open source project that implements the OSGi R7 version of the Remote Services and Remote Service Admin specifications.

This repo holds both a Distribution and Discovery provider that can be plugged in underneath ECF's Remote Services implementation. The following links provide access to resources about the Remote Services and Remote Service Admin (RSA) implementations themselves, along with linkt to other available Distribution and Discovery providers.

ECF Home page
ECF Wiki
ECF Download page
ECF Distribution Providers
ECF Discovery Providers

Installing and Running an Example Remote Service in Apache Karaf

Apache Karaf is an OSGi-based server. The following shows how to use the Hazelcast Discovery and Distribution providers to export and use an example remote service. The source for the example remote service projects is located:

TimeService API Project - depended upon by both the Host and the Consumer projects.

TimeService Host Project - exports an implementation or 'host' of the TimeService API.

TimeService Consumer Project - discovers and imports and then calls the remote services.

TimeService Host

To install the ECF Remote Services implementation, and the Hazelcast Discovery and Distribution providers:

In one instance of Karaf, add these two repos at the console

karaf@root()> feature:repo-add https://download.eclipse.org/rt/ecf/latest/karaf-features.xml
Adding feature url https://download.eclipse.org/rt/ecf/latest/karaf-features.xml
karaf@root()> feature:repo-add https://raw.githubusercontent.com/ECF/HazelcastProvider/master/build/karaf-features.xml
Adding feature url https://raw.githubusercontent.com/ECF/HazelcastProvider/master/build/karaf-features.xml

Then type this command to install ECF Remote Services, and the Hazelcast providers

karaf@root()> feature:install ecf-rs-hazelcast

Type this command to configure the Timeservice Host to use the Hazelcast manager distribution provider

karaf@root()> system:property -p service.exported.configs ecf.jms.hazelcast.manager

To install, start, export the TimeService host

karaf@root()> feature:install ecf-rs-examples-timeservice-host
19:41:09.134;EXPORT_REGISTRATION;exportedSR=[com.mycorp.examples.timeservice.ITimeService];cID=JMSID[hazelcast://localhost/defaultRemoteServicesTopic];rsId=1
--Endpoint Description---
<endpoint-descriptions xmlns="http://www.osgi.org/xmlns/rsa/v1.0.0">
  <endpoint-description>
    <property name="ecf.endpoint.id" value-type="String" value="hazelcast://localhost/defaultRemoteServicesTopic"/>
    <property name="ecf.endpoint.id.ns" value-type="String" value="ecf.namespace.jmsid"/>
    <property name="ecf.endpoint.ts" value-type="Long" value="1569811269048"/>
    <property name="ecf.exported.async.interfaces" value-type="String" value="*"/>
    <property name="ecf.rsvc.id" value-type="Long" value="1"/>
    <property name="endpoint.framework.uuid" value-type="String" value="1c5bf449-700a-4322-bf2b-850724f3a65c"/>
    <property name="endpoint.id" value-type="String" value="eb4fb828-5dd7-4e22-85aa-906f3dad1d5e"/>
    <property name="endpoint.package.version.com.mycorp.examples.timeservice" value-type="String" value="2.0.0"/>
    <property name="endpoint.service.id" value-type="Long" value="136"/>
    <property name="objectClass" value-type="String">
      <array>
        <value>com.mycorp.examples.timeservice.ITimeService</value>
      </array>
    </property>
    <property name="remote.configs.supported" value-type="String">
      <array>
        <value>ecf.jms.hazelcast.manager</value>
      </array>
    </property>
    <property name="remote.intents.supported" value-type="String">
      <array>
        <value>osgi.basic</value>
        <value>passByValue</value>
        <value>exactlyOnce</value>
        <value>ordered</value>
        <value>osgi.async</value>
        <value>hazelcast</value>
      </array>
    </property>
    <property name="service.imported" value-type="String" value="true"/>
    <property name="service.imported.configs" value-type="String">
      <array>
        <value>ecf.jms.hazelcast.manager</value>
      </array>
    </property>
  </endpoint-description>
</endpoint-descriptions>
---End Endpoint Description
TimeService host registered with registration=org.apache.felix.framework.ServiceRegistrationImpl@19fe5be4
karaf@root()>     

The above output indicates that the TimeService has been exported. Also the Hazelcast discovery has advertised this remote service via a multicast group on the current LAN.

TimeService Consumer

In a second Karaf instance (not the same process as the TimeService host) give the following Karaf commands:

karaf@root()> feature:repo-add https://download.eclipse.org/rt/ecf/latest/karaf-features.xml
Adding feature url https://download.eclipse.org/rt/ecf/latest/karaf-features.xml
karaf@root()> feature:repo-add https://raw.githubusercontent.com/ECF/HazelcastProvider/master/build/karaf-features.xml
Adding feature url https://raw.githubusercontent.com/ECF/HazelcastProvider/master/build/karaf-features.xml
karaf@root()> feature:install ecf-rs-examples-timeservice-consumer-async
karaf@root()> feature:install ecf-rs-hazelcast

After a few seconds to download, install and start bundles, and a few more seconds to discover the exported TimeService in the Hazelcast group, you should see output like this on the consumer, indicating that the remote service was discovered, imported, injected into the example consumer code, which calls the remote service and prints out a result along with the IMPORT_REGISTRATION and imported endpoint-description.

Adding feature url https://raw.githubusercontent.com/ECF/HazelcastProvider/master/build/karaf-features.xml
karaf@root()> feature:install ecf-rs-examples-timeservice-consumer
karaf@root()> feature:install ecf-rs-hazelcast
karaf@root()> Current time on remote is: 1569811897139
19:51:37.153;IMPORT_REGISTRATION;importedSR=[com.mycorp.examples.timeservice.ITimeService, com.mycorp.examples.timeservice.ITimeServiceAsync];cID=JMSID[hazelcast://localhost/defaultRemoteServicesTopic];rsId=1
--Endpoint Description---
<endpoint-descriptions xmlns="http://www.osgi.org/xmlns/rsa/v1.0.0">
  <endpoint-description>
    <property name="ecf.endpoint.id" value-type="String" value="hazelcast://localhost/defaultRemoteServicesTopic"/>
    <property name="ecf.endpoint.id.ns" value-type="String" value="ecf.namespace.jmsid"/>
    <property name="ecf.endpoint.ts" value-type="Long" value="1569811269048"/>
    <property name="ecf.exported.async.interfaces" value-type="String" value="*"/>
    <property name="ecf.rsvc.id" value-type="Long" value="1"/>
    <property name="endpoint.framework.uuid" value-type="String" value="1c5bf449-700a-4322-bf2b-850724f3a65c"/>
    <property name="endpoint.id" value-type="String" value="eb4fb828-5dd7-4e22-85aa-906f3dad1d5e"/>
    <property name="endpoint.package.version.com.mycorp.examples.timeservice" value-type="String" value="2.0.0"/>
    <property name="endpoint.service.id" value-type="Long" value="136"/>
    <property name="objectClass" value-type="String">
      <array>
        <value>com.mycorp.examples.timeservice.ITimeService</value>
      </array>
    </property>
    <property name="remote.configs.supported" value-type="String">
      <array>
        <value>ecf.jms.hazelcast.manager</value>
      </array>
    </property>
    <property name="remote.intents.supported" value-type="String">
      <array>
        <value>osgi.basic</value>
        <value>passByValue</value>
        <value>exactlyOnce</value>
        <value>ordered</value>
        <value>osgi.async</value>
        <value>hazelcast</value>
      </array>
    </property>
    <property name="service.imported.configs" value-type="String">
      <array>
        <value>ecf.jms.hazelcast.member</value>
      </array>
    </property>
  </endpoint-description>
</endpoint-descriptions>
---End Endpoint Description

Notice the line

karaf@root()> Current time on remote is: 1569811897139

This indicated that the consumer called the remote TimeService and received a result of the current time. The code for the consumer class is here

On the host console, you should see output like this:

karaf@root()> TimeServiceImpl:  Received call to getCurrentTime()

The code for the TimeServiceImpl class is here