/gv-adapter-redis

Implementation of a Redis adapter for GV ESB

Primary LanguageJava

GreenVulcano VCL Adapter for Redis (Alpha)

This is the implementation of a GreenVulcano VCL Adapter for the Redis database platform. It's meant to run as an Apache Karaf bundle.

Getting started

Installation

First, you need to have installed Java Development Kit (JDK) 11 or above.

Then, you need to have installed Apache Karaf 4.2.x. Please refer to the following links for further reference: Apache Karaf

Next, you need to install the GreenVulcano engine on the Apache Karaf container. Please refer to this link for further reference.

In order to install the bundle in Apache Karaf to use it for a GreenVulcano application project, you need to install its dependencies. Open the Apache Karaf terminal by running the Karaf executable and type the following command:

karaf@root()> bundle:install -s mvn:org.apache.commons/commons-pool2/2.6.0
karaf@root()> bundle:install -s -l 82 mvn:redis.clients/jedis/3.1.0
karaf@root()> bundle:install -s -l 92 mvn:it.greenvulcano.gvesb.adapter/gvvcl-redis/4.1.0-SNAPSHOT

Using the VCL adapter in your GreenVulcano project

In order to use the features of the Redis adapter in your GreenVulcano project, you need to define a proper System-Channel-Operation set of nodes. You can do that by manually editing the GVCore.xml file, or by using DeveloperStudio. In that case, you will have to download the dtds/ folder on this repository and replace it with the one in your current project.

Declaring the System-Channel-Operation for the Redis database

Let's assume you want to interact with your database in "localhost". By default, that's gonna be at 127.0.0.1:6379. Insert the <redis-call> XML node in the <Systems></Systems> section of file GVCore.xml. Here's an example:

<System id-system="MySystem" system-activation="on">
    <Channel enabled="true" endpoint="redis://localhost:6379" id-channel="redis-channel" type="RedisAdapter">
    	<redis-call name="aRedisCallOp" type="call">
      	 <set key="test1" value="test1value"/>
           <get key="test1"/>
      </redis-call>
	</Channel>
</System>

Some constraints apply to these XML nodes.

  • The <Channel> XML node must comply with the following syntax:

    • endpoint must contain a URI string correctly referencing the hostname and the port of an operational Redis server.

  • The <redis-call> XML node must comply with the following syntax:

    • type must be declared and set equal to "call";
    • name must be declared: it defines the name of the Operation node;
    • uri optional: if you want to specify a Redis connection different from the channel endpoint;

  • The redis-call node supports four types of operation:

    • get to retrieve data from Redis;
    • set to put into Redis the GVBuffer data as value for the specified key;
    • delete to delete the specified key;
    • keys to retrieve the keys matching the specified pattern;

When we're done defining our System node, we can now use it in a Service-Operation, such as:

<Services>
            <Description>This section contains a list of all services provided by GreenVulcano ESB</Description>
            <Service group-name="DEFAULT_GRP" id-service="testService"
                     service-activation="on" statistics="off">
                <Operation class="it.greenvulcano.gvesb.core.flow.GVFlowWF"
                           loggerLevel="ALL" name="testOperation"
                           operation-activation="on" type="operation">
                    <Flow first-node="RedisCall">
                        <GVOperationNode class="it.greenvulcano.gvesb.core.flow.GVOperationNode"
                                         id="RedisCall" id-channel="redis-channel"
                                         id-system="REDIS" input="input"
                                         next-node-id="terminated" op-type="call"
                                         operation-name="ciao" point-x="231" point-y="150"
                                         type="flow-node"/>
                        <GVEndNode class="it.greenvulcano.gvesb.core.flow.GVEndNode"
                                   id="terminated" op-type="end" output="input"
                                   point-x="435" point-y="150" type="flow-node"/>
                    </Flow>
                </Operation>
            </Service>
</Services>