Packaging Artifacts as C-App Archive

Carbon applications (cApp) deployer is a specific feature of WSO2 CEP, which deploys WSO2 CEP-specific deployable artifacts using a single CAR file.

cApp deployable artifacts and types

You can deploy all deployable artifacts, and also the stream definitions using Carbon apps (cApps). Given below is a list of deployable artifacts and the associated types.

Creating a cApp

Follow the steps below to create a cApp with the following structure.

├──artifacts.xml
├──WSO2EventReceiver_1.0.0
│       ├──artifact.xml
│       └──WSO2EventReceiver-1.0.0.xml
└──HighFrequentTweetsLogger_1.0.0
        ├──artifact.xml
        └──HighFrequentTweetsLogger-1.0.0.xml

1. Create the top level artifacts.xml file of the cApp which defines the set of folders included in it as shown below. 

   <?xml version="1.0" encoding="UTF-8"?><artifacts>
       <artifact name="SampleCApp" version="1.0.0" type="carbon/application">
           <dependency artifact="WSO2EventReceiver" version="1.0.0" include="true" serverRole="ComplexEventProcessor"/>
   	<dependency artifact="HighFrequentTweetsLogger" version="1.0.0" include="true" serverRole="ComplexEventProcessor"/>
       </artifact>
   </artifacts>

2. Create separate directories in the top level of the cApp for the two dependencies (WSO2EventReceiver_1.0.0 and HighFrequentTweetsLogger_1.0.0) defined in the artifacts.xml file. 

   You can have multiple dependencies as required with a directory for each of them in the same level as the artifacts.xml file in the cApp. Include the name and the version of the artifact in the name of the directory.

   Each dependency directory should contain an artifact.xml file. 

3.  Create an artifact.xml file inside all dependency directories. For example, the artifact.xml file of the WSO2EventReceiver_1.0.0 dependency directory is as follows.

   <?xml version="1.0" encoding="UTF-8"?>
   <artifact name="WSO2EventReceiver" version="1.0.0" type="event/receiver" serverRole="ComplexEventProcessor">
       <file>WSO2EventReceiver-1.0.0.xml</file>
   </artifact>

4. Create the WSO2EventReceiver-1.0.0.xml file, which is the actual event receiver file that you deploy in WSO2 CEP inside the WSO2EventReceiver_1.0.0 directory. 

5. Create the HighFrequentTweetsLogger-1.0.0.xml file, which is the actual event publisher file that you deploy in WSO2 CEP inside the HighFrequentTweetsLogger_1.0.0 directory.

Deploying a cApp

Follow the steps below to deploy a cApp.

1. Log in to WSO2 CEP management console using admin/admin credentials.
2. Click Main, and then click Add in the Carbon Applications menu.
3. Click Choose File as shown below.
   
   
4. Select the CAR file you need to upload as shown below.
   
5. Click Upload.

6. Click Main, and then click List in the Carbon Applications menu. You see the file added to the list of deployed CAR files as shown below.

   If there is a deployment failure, the faulty Carbon applications and the deployment error will be displayed in the UI.

   

Undeploying a cApp

Follow the steps below to undeploy a cApp.

1. Log in to WSO2 CEP management console using admin/admin credentials.
2. Click Main, and then click List in the Carbon Applications menu. 
3. Click the corresponding Delete link of the relevant Carbon application, which you want to delete as shown below.