15.4.1. Example Email Notification Workflow

This example uses the Activiti Eclipse BPMN 2.0 Designer to set up an email notification business process. The example relies on an SMTP server listening on localhost, port 25.

The example sets up a workflow that can accept parameters used to specify the sender and recipient of the mail.

${fromSender}

Used to specify the sender

${toEmail}

Used to specify the recipient

Once you have defined the workflow, drag and drop components to create the workflow. This simple example uses only a StartEvent, MailTask, and EndEvent.

Email notification process

[D]

After creating the workflow, adjust the generated XML source code to use the variables inside the <serviceTask> tag shown in the following listing. 

<?xml version="1.0" encoding="UTF-8"?>
<definitions
 xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns:activiti="http://activiti.org/bpmn"
 xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI"
 xmlns:omgdc="http://www.omg.org/spec/DD/20100524/DC"
 xmlns:omgdi="http://www.omg.org/spec/DD/20100524/DI"
 typeLanguage="http://www.w3.org/2001/XMLSchema"
 expressionLanguage="http://www.w3.org/1999/XPath"
 targetNamespace="http://www.activiti.org/test">
 <process id="EmailNotification" name="emailNotification">
   <documentation>Simple Email Notification Task</documentation>
   <startEvent id="startevent1" name="Start"></startEvent>
   <sequenceFlow id="flow1" name="" sourceRef="startevent1"
     targetRef="mailtask1"></sequenceFlow>
   <endEvent id="endevent1" name="End"></endEvent>
   <sequenceFlow id="flow2" name="" sourceRef="mailtask1"
     targetRef="endevent1"></sequenceFlow>
   <serviceTask id="mailtask1" name="Email Notification"
     activiti:type="mail">
     <extensionElements>
       <activiti:field name="to" expression="${toEmail}"
       ></activiti:field>
       <activiti:field name="from" expression="${fromSender}"
       ></activiti:field>
       <activiti:field name="subject" expression="Simple Email Notification"
       ></activiti:field>
       <activiti:field name="text">
         <activiti:expression><![CDATA[Here is a simple Email Notification
         from ${fromSender}.]]></activiti:expression>
       </activiti:field>
     </extensionElements>
   </serviceTask>
 </process>
 <bpmndi:BPMNDiagram id="BPMNDiagram_EmailNotification">
   <bpmndi:BPMNPlane bpmnElement="EmailNotification"
     id="BPMNPlane_EmailNotification">
     <bpmndi:BPMNShape bpmnElement="startevent1" id="BPMNShape_startevent1">
       <omgdc:Bounds height="35" width="35" x="170" y="250"></omgdc:Bounds>
     </bpmndi:BPMNShape>
     <bpmndi:BPMNShape bpmnElement="endevent1" id="BPMNShape_endevent1">
       <omgdc:Bounds height="35" width="35" x="410" y="250"></omgdc:Bounds>
     </bpmndi:BPMNShape>
     <bpmndi:BPMNShape bpmnElement="mailtask1" id="BPMNShape_mailtask1">
       <omgdc:Bounds height="55" width="105" x="250" y="240"></omgdc:Bounds>
     </bpmndi:BPMNShape>
     <bpmndi:BPMNEdge bpmnElement="flow1" id="BPMNEdge_flow1">
       <omgdi:waypoint x="205" y="267"></omgdi:waypoint>
       <omgdi:waypoint x="250" y="267"></omgdi:waypoint>
     </bpmndi:BPMNEdge>
     <bpmndi:BPMNEdge bpmnElement="flow2" id="BPMNEdge_flow2">
       <omgdi:waypoint x="355" y="267"></omgdi:waypoint>
       <omgdi:waypoint x="410" y="267"></omgdi:waypoint>
     </bpmndi:BPMNEdge>
   </bpmndi:BPMNPlane>
 </bpmndi:BPMNDiagram>
</definitions>

In Eclipse, select the project, then right click and select Create deployment artifacts to generate the components and package them in a .bar file for deployment in the openidm/workflow directory.

After you deploy the .bar, create a script named openidm/script/triggerEmailNotification.js. The script invokes the workflow. 

/*
 * Calling 'EmailNotification' workflow
 */

var params = {
 "_key" : "EmailNotification",
 "fromSender" : "noreply@openidm",
 "toEmail" : "jdoe@example.com"
};

openidm.action('workflow/processinstance', {"_action" : "createProcessInstance"}, params);

You can also invoke the workflow over the REST interface with the following REST command: 

$ curl
 --header "X-OpenIDM-Username: openidm-admin" 
 --header "X-OpenIDM-Password: openidm-admin"
 --data '{"_key":"EmailNotification", "fromSender":"noreply@openidm", "toEmail":"jdoe@example.com"}'
 --request POST 
 "http://localhost:8080/openidm/workflow/processinstance?_action=createProcessInstance"

To schedule the workflow to be invoked regularly, create a schedule configuration object named openidm/conf/schedule-EmailNotification.json. The following schedule invokes the workflow once per minute. 

{
   "enabled" : true,
   "type" : "cron",
   "schedule" : "0 0/1 * * * ?",
   "invokeService" : "script",
   "invokeContext" : {
       "script" : {
           "type" : "text/javascript",
           "file" : "script/triggerEmailNotification.js"
       },
   }
}