Triggers in Enterprise Data Quality are scripts (JavaScript or Groovy) that can be called at various trigger points in the EDQ system. There are two types of triggers: predefined triggers and custom triggers.

Knowledge of Javascript or Groovy is required to create and deploy custom triggers in EDQ.

Custom triggers must be stored in the triggers subdirectory of the EDQ config (configuration) directory. New or updated triggers are loaded automatically without requiring a system restart.

You can use the functions of the script API to create your triggers. These functions are defined in the trigger code. Although the examples in this document are JavaScript, the same API is available in Groovy.

The following are descriptions of each function in this API.

getPath()

Returns a string that defines the path that the trigger will handle. Each trigger point has a unique path. Any trigger that matches a given path is executed when the trigger point is reached. For more information about trigger points, see Understanding EDQ Trigger Points.

This function is a regular expression. For example, the path /log/com\.datanomic\..* would match any logging path where the logger name contains the string datanomic (in other words, any logger defined in EDQ, the word "datanomic" being another name for EDQ).

run(path, id, env, arg1, arg2 ...)

Executes the trigger. For more information about what is returned by the trigger API for each of these variables, see Understanding EDQ Trigger Points.

path

The path of the trigger, for example /runtime/engine/interval/end.

id

The trigger ID. The ID is set when the trigger is configured in the Director user interface. The ID is null for simple triggers.

env

The trigger environment in the form of one or more key/value pairs, for example env.project = project name. The env input is specific to the trigger point. These values are exposed as properties of the env object in the script. Most trigger points will pass in the associated EDQ project ID and project name.

arg

Extra arguments that are specific to the trigger point. For example, the Interval end trigger point returns the following: Task context object, process options, interval number (>= 1), execution statistics.

filter(path, env)

(Optional function) Filters out the trigger before it can be executed. Use this filter to avoid the overhead of executing a trigger that will not be needed. Return true to enable the trigger or false to disable it.

path

The path of the trigger.

env

The trigger environment in the form of one or more key/value pairs. The env input is specific to the trigger point. These values are exposed as properties of the env object in the script. Most trigger points will pass in the associated EDQ project ID and project name. In the following example, the trigger is enabled only if the associated project is named "My project."

function filter(path, env) {
  return env.project == 'My project';
}

getLevel()

(Optional function) Returns the maximum level the trigger will accept. For example, the following statement allows the trigger to accept all levels, regardless of other settings in the trigger system. For more information about setting levels, see Setting Trigger Levels.

function getLevel() {
  return Level.SEVERE;
}

getTriggerNames(path, env)

(Optional function) Returns an array of TriggerName objects for display in the Director user interface. For more information, see Exposing Triggers in a Job Configuration. Getting trigger names and exposing them in the Director interface is only possible with the job configuration screen.

You can specify additional configuration for script triggers in properties files. Access to these properties is by means of a predefined object named config, which is available in all triggers. The base directory in EDQ for these properties files is the subdirectory config within the triggers directory. The following are useful methods for the config object.

config.getTriggerConfigFiles(base, pattern)

Returns an array of file objects whose names match a search pattern within a specified directory in the triggers/config directory.

base

The name of a directory within the triggers/config directory.

pattern

A regular expression (regex) that defines the search pattern to match.

config.loadProps(file)

Loads a specified Java properties file and return it as a JavaScript object.

file

The name of the Java properties file.

This section describes the trigger points within EDQ at which you can call custom triggers.

Log Message

Called whenever a log message is generated in the system.

Component	Description
Path	/log/loggername
Env	null
Arguments	java.util.logging.LogRecord

Syslog Message

Called whenever a high-level syslog log message is generated. The source argument is a Java object that contains details of the event source. It can be converted to string for display.

Component	Description
Path	/syslog
Env	env.event = event_name env.source = event_source_as_string
Arguments	event_name, source, message

Process start

Called when a process starts. The arguments are Java objects that contain information on the process configuration.

Component	Description
Path	/runtime/engine/task/start
Env	env.project = project_name env.projectID = project_ID env.missionname = job_name env.processname = process_name
Arguments	Task_context_object, process_options

Note:

When specifying the path for starting a task, the trigger script must include addLibrary('runtime') to avoid the trigger script from throwing an error.

Process end

Called when a process stops. The arguments are Java objects that contain information on the process configuration.

Component	Description
Path	/runtime/engine/task/end
Env	env.project = project_name env.projectID = project_ID env.missionname = job_name env.processname = process_name
Arguments	Task_context_object, process_options

Note:

When specifying the path for ending a task, the trigger script must include addLibrary('runtime') to avoid the trigger script from throwing an error.

Interval end

Called at the end of a normal process or at the end of each interval of a process that is run in interval mode. Returns statistics on the number of records executed, etc.

Component	Description
Path	/runtime/engine/interval/end
Env	env.project = project_name env.projectID = project_ID env.missionname = job_name env.processname = process_name
Arguments	Task_context_object, process_options, interval_number (>= 1), execution_statistics

Before job phase

Called in a job configuration for 'pre phase' execution.

Component	Description
Path	/missions/phase/pre
Env	env.project = project_name env.projectID = project_ID env.missionname = job_name env.processname = process_name
Arguments	None

After job phase

Called in a job configuration for 'post phase' execution.

Component	Description
Path	/missions/phase/post
Env	env.project = project_name env.projectID = project_ID env.missionname = job_name env.processname = process_name
Arguments	None

On match decision

Called when EDQ must make a decision about a potential match. This is known as a relationship decision trigger. Relationship triggers can include methods that return the relationship and decision data needed to perform matching. This trigger point is specific to Match Review.

Component	Description
Path	/matchreview/relationship/decision/
Env	env.project = project_name
Arguments	A list of TriggerInfo methods. Each contains data for one relationship. See Understanding TriggerInfo Methods for descriptions of these methods.

When a case is created

Called when a case is created where the case belongs to the respective case source.

Component	Description
Path	/casemanagement/create/<case source name>
Env	env.sourceName = case source name env.caseType = the type of the case or alert env.currentState = the current state of the created case
Arguments	com.datanomic.director.casemanagement.beans.CaseBean

When a case or alert has transitioned

Called after a case or alert has transitioned into the next logical state corresponding to the respective workflow.

Component	Description
Path	/casemanagement/transition/<workflow name>/<transition>
Env	env.sourceName = case source name env.caseType = the type of the case, 'case' or 'alert' env.currentState = the current state of the created case
Arguments	com.datanomic.director.casemanagement.beans.CaseBean,java.util.List<com.datanomic.director.casemanagement.beans.CaseHistoryBean>,comment,restrictingPermission Where comment is entered by the user and restrictingPermission is the permission required to access the comment.

When a case or alert has been updated

Called when a case or alert is updated by a user. This includes assignment, state change, priority change, or performing any other edit.

Component	Description
Path	/casemanagement/update/<case source name>
Env	env.sourceName = case source name env.caseType = the type of the case, 'case' or 'alert' env.currentState = the current state of the created case
Arguments	com.datanomic.director.casemanagement.beans.CaseBean,java.util.List<com.datanomic.director.casemanagement.beans.CaseHistoryBean>,comment,restrictingPermission Where comment is entered by the user and restrictingPermission is the permission required to access the comment

When a comment is added for a case or alert

Called when a comment is added for a case or alert.

Component	Description
Path	/casemanagement/commented/<case source name>
env.sourceName = case source name Env	env.caseType = the type of the case, 'case' or 'alert' env.currentState = the current state of the created case
Arguments	com.datanomic.director.casemanagement.beans.CaseBean,java.util.List<com.datanomic.director.casemanagement.beans.CaseHistoryBean>,comment,restrictingPermission Where comment is the user entered comment and restrictingPermission is the permission required to access the comment.

After a system update occurs

Called after a case or alert is updated as part of an escalation or bulk update.

Component	Description
Path	/casemanagement/systemupdate/<case source name>
Env	env.sourceName = case source name env.caseType = the type of the case, 'case' or 'alert' env.currentState = the current state of the created case
Arguments	com.datanomic.director.casemanagement.beans.CaseBean,java.util.List<com.datanomic.director.casemanagement.beans.CaseHistoryBean>,comment,restrictingPermission Where comment is the user entered comment and restrictingPermission is the permission required to access the comment.

This section explains each of the methods that are associated with the TriggerInfo trigger point. These methods are specific to the TriggerInfo trigger point for use in Match Review.

Every trigger point has an associated level, which is a java.util.logging.Level value. By default trigger calls with a level lower than INFO are ignored.

One way to modify the level is to create a file named levels.properties in the triggers subdirectory of the config directory. This file can contain both a default level and one or more override levels for individual paths. Example 6-1 sets the default level to FINE and sets the level for the path /runtime/engine/.* to FINER. You can define your own prefix for the pattern and level properties.

Another way to modify the level is to define a getLevel function in the trigger. See Configuring Triggers Using the Script Trigger API for a description.

default = fine
runtime.pattern = /runtime/engine/.*
runtime.level   = finer

1. Load the internal JavaScript JMS library.

   addLibrary("jms");
   

2. Load properties that define the JMS configuration. These properties are augmented with the JMS settings from the standard realtime.properties file that is shipped in the EDQ configuration directory. The default version of this file defines properties for the open-source ActiveMQ message broker that is bundled with EDQ. At minimum, the trigger should supply a value for the destination property, which names the JMS topic or queue to use.
3. Create a JMS object.

   var jms = JMS.open(props);
   

4. Send a text message.

   jms.send(str)
   

5. Send a JMS map message built from a script object.

   jms.sendMap(jsobj)
   

6. Create a text message. Properties and header values can be set on the message before transmission.

   var msg = jms.createTextMessage(str)
   

7. Create a map message. Properties and header values can be set on the message before transmission.

   var msg = jms.createMapMessage(jsobj)
   

8. Send a message that was created by one of the two preceding methods.

   jms.sendMessage(msg)

Triggers are selected for use in a job when configuring a job phase in Director. They can be set to run before or after a job phase. To make triggers available for selection on the configuration screen, each trigger must be able to return a list of names. This allows one trigger to perform multiple tasks as needed.

A trigger name has the following components:

• an internal ID that is passed to the trigger run function. See Configuring Triggers Using the Script Trigger API for a description of this function.

• a visible label

• a group name

Trigger names with the same group are shown as a single node in the job configuration screen.

To create a new trigger name:

var n1 = new TriggerName(id, label)
n1.group = "My group";

To return trigger names from a trigger:

To return trigger names, use the getTriggerNames function as shown in this example.

function getTriggerNames(path, env) {
  var n1 = new TriggerName(id1, label1);
  var n2 = new TriggerName(id2, label2);
  ...
  n1.group = "My group";
  n2.group = "My group";
  ...
  return [n1, n2 ...]
}

See Configuring Triggers Using the Script Trigger API for more information about getTriggerNames.

The following are examples of how you can use custom triggers.

Example 1   Use a Trigger to Send Log Messages Via JMS

In this example, the logging library imports a logging object that can be used to format and output the message. The JMS properties file is loaded from triggers/config/jms/jms.properties in the EDQ configuration directory.

// Test trigger for task running with JMS
addLibrary("logging");
addLibrary("jms");
 
function getPath() {
  return "/log/com\.datanomic\..*";
}
function run(path, id, env, logrecord) {
 
  var pfiles = config.getTriggerConfigFiles("jms", 
                           "jms\\.properties");
 
  if (pfiles.length > 0) {
    var props = config.loadProps(pfiles[0]);
 
    var jms = JMS.open(props);
    var msg = logging.format(logrecord);
    var len = msg.length;

// Remove trailing newlines
 
    while (len > 0) {
      var c = msg.charAt(len - 1);
 
      if (c != '\n' && c != '\r') {
        break;
      }
 
      len--;
    }

    jms.send(msg.substring(0, len));
    jms.close();
  }
}

Example 2   Use a Trigger to Send Syslog Messages Via JMS

In this example, the special id directive on the first line (#! id : syslog) defines the internal ID of the trigger. If there is more than one trigger definition with the same ID, the later one replaces the former one. In a standard EDQ install, there is a predefined syslog trigger that logs messages through the standard logging API. Adding the id directive in this example causes the JMS syslog trigger to replace the predefined trigger.

#! id : syslog
 
// Test trigger for task running with JMS
 
addLibrary("logging");
addLibrary("jms");
 
function getPath() {
  return "/syslog";
}
 
function getLevel() {
  return Level.SEVERE;
}

function run(path, id, env, level, event, source, message) {
 
  var pfiles = config.getTriggerConfigFiles("jms", 
                "jms\\.properties");
  var props  = null;
 
  if (pfiles.length == 0) {
    logger.log(Level.WARNING, "syslogger called but no properties");
  } else {
 
    props = config.loadProps(pfiles[0]);
 
    var jms    = JMS.open(props);
    var xml    = <syslog level={level}><source>{source}</source><message>{message}</message></syslog>
 
    logger.log(Level.INFO, "xml = {0}", xml.toXMLString());
    jms.send(xml.toXMLString());
    jms.close();
  }
}

Example 3   Use a Trigger for Mission Phase Notification

In this example, a couple of trigger names are defined and are exposed to the job configuration screen. The trigger writes a log message in this example, but it could also be configured to send JMS notifications.

// Test trigger for misssion phase notification
 
addLibrary("logging");
 
function getPath() {
  return "/missions/phase/.*";
}
 
function run(path, id, env) {
 logger.log(Level.INFO, "phase called with path {0} and id {1}", path, id);
}

function getTriggerNames(path, env) {
  var n1 = new TriggerName("logme", "logme2");
  n1.group = "logmegroup";
 
  var n2 = new TriggerName("n2", "n2");
  n2.group = "logmegroup";
  return [n1, n2];
}