org.qbroker.flow

Class MonitorAgent

java.lang.Object

org.qbroker.flow.MonitorAgent

All Implemented Interfaces:

java.lang.Runnable, Service

public class MonitorAgent
extends java.lang.Object
implements Service, java.lang.Runnable

MonitorAgent is a Java container hosting multiple MonitorGroups and MessageFlows. The MonitorGroup contains various monitors that periodically check if something have happened. Whereas the MessageFlow is to process messages for on-demand services.

MonitorAgent periodically runs the registered monitors. Registered monitors are grouped according to their dependencies. The monitors in a same group are guaranteed to be checked in the same order as they are in the group. However, the order of different groups is not honored by MonitorAgent due to MT implementation.

Each registered monitore contains three components, a MonitorReport to generate the latest report on the monitored object, a MonitorAction to handle the monitor report, and a set of time windows in which the monitor is expected to be active. It first calls MonitorReport.generateReport(currentTime) that returns a report in a Map object. If there is no any exceptions, it checks the latest monitor time with the predefined configuration of the time windows, defined in ActiveTime, to see if the monitor is late or in time. The result is passed through in status. No matter what status is, the MonitorAction.performAction(status, currentTime, report) will always be called.

If an exception is thrown by MonitorReport.generateReport(currentTime), the content of the report is invalid. It does not make sense to check on the invalid report. Therefore MonitorAgent always catches the exception and skips both the checking process and the action if any exception is caught.

It is up to developers to implement both interfaces of MonitorReport and MonitorAction. The return object of MonitorReport.generateReport(currentTime) is a Map. It is an opaque container for developers to put anything about the monitor report in it. It may be the status code indicating the latest status or anything, or the timestamp of a file, or a ResultSet of a database query, etc, as long as the associated action knows how to retrieve them.

MonitorAgent also supports shared information. Some of the reports can have their test results shared with others as the dependencies or merged into a new report. The shared information is called the internal report that is a Map, too. The other objects can access them via ReportQuery report.

You can disable all the monitor groups via some monitor jobs. To do that, you have to define the report and specify the correct ReportMode.

MonitorAgent also can be configured to pick up its configuration changes automatically from the configuration repository. The object needs to be defined in the default group. Its name must be specified within ConfigRepository tag.

MonitorAgent can also host multiple message flows. A message flow is a message driven application for message broker service. With the message flow, you can have MonitorAgent to pick up and deliver JMS messages via various transports. In order to configure a message flow, you need to define Receivers, Nodes and Persisters under MessageFlow list. For detailed information, please reference the docs for QFlow.

The default MessageFlow is the flow with the name of default. It is the dedicated MessageFlow for event escalations. It shoule be always the first message flow if it is defined. In this case, URL should not be defined in the master configuration file since all the events will be escalated by the default MessageFlow.

Author:

yannanlu@yahoo.com

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	FILE_SEPARATOR
protected static java.lang.String[]	reportStatusText

Fields inherited from interface org.qbroker.common.Service

DEBUG_CTRL, DEBUG_DIFF, DEBUG_INIT, DEBUG_LOAD, DEBUG_LOOP, DEBUG_NONE, DEBUG_REPT, DEBUG_TRAN, DEBUG_UPDT, SERVICE_CLOSED, SERVICE_DISABLED, SERVICE_PAUSE, SERVICE_READY, SERVICE_RETRYING, SERVICE_RUNNING, SERVICE_STANDBY, SERVICE_STOPPED, statusText

Constructor Summary

Constructors

Constructor and Description
MonitorAgent(java.util.Map props)
MonitorAgent(java.util.Map props, int debugForReload, java.lang.String configFile)

Method Summary

Modifier and Type	Method and Description
void	close() closes all opened resources
int	doRequest(Event req, int timeout) It processes the request according to the preconfigured rulesets.
int	getDebugMode() returns the debug mode of the service
java.lang.String	getName() returns the name of the service
java.lang.String	getOperation() returns the string of the operation
static java.util.Map	getPrivateReport() returns the report map stored in the privateReport
static java.util.Map<java.lang.String,java.lang.Object>	getReport(java.lang.String rptName) returns a copy of the shared report
static java.lang.String[]	getReportNames() returns all the names of the shared reports
int	getStatus() returns the status of the service
static void	initReport(java.lang.String rptName, long currentTime, int status, int skippingStatus) initializes the static shared report without keyList
static void	initReport(java.lang.String rptName, java.lang.String[] keyList, java.util.Map latest, int reportMode) initializes the static shared report with keyList
boolean	keepRunning(XQueue xq)
static int	loadIncludedProperties(java.util.List group, java.lang.String cfgDir, int show, java.util.Map props, java.util.Map policy) It checks the loaded primay include on its ClassName for each string item of the given group.
static int	loadListProperties(java.util.List list, java.lang.String configDir, int show, java.util.Map props) It loads the property map from configDir for each string item of the given list and adds the property map to the given props.
static void	main(java.lang.String[] args) The configuration parameters are stored in the property file, Agent.json, that lists all monitorGroups, etc.
static java.lang.String	query(MessagePersister pstr, javax.jms.Message msg) sends a query message via the given persister and waits for response.
void	run()
void	setDebugMode(int debug) sets the debug mode of the service
void	start() starts the main workflow and controls all groups of jobs and msg flows.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

FILE_SEPARATOR

public static final java.lang.String FILE_SEPARATOR

reportStatusText

protected static final java.lang.String[] reportStatusText

Constructor Detail

MonitorAgent

public MonitorAgent(java.util.Map props)

MonitorAgent

public MonitorAgent(java.util.Map props,
                    int debugForReload,
                    java.lang.String configFile)

Method Detail

run

public void run()

Specified by:

run in interface java.lang.Runnable

initReport

public static void initReport(java.lang.String rptName,
                              long currentTime,
                              int status,
                              int skippingStatus)

initializes the static shared report without keyList

initReport

public static void initReport(java.lang.String rptName,
                              java.lang.String[] keyList,
                              java.util.Map latest,
                              int reportMode)

initializes the static shared report with keyList

getReport

public static java.util.Map<java.lang.String,java.lang.Object> getReport(java.lang.String rptName)

returns a copy of the shared report

getReportNames

public static java.lang.String[] getReportNames()

returns all the names of the shared reports

getPrivateReport

public static java.util.Map getPrivateReport()

returns the report map stored in the privateReport

start

public void start()

starts the main workflow and controls all groups of jobs and msg flows. It dispatches the job groups according to their schedules while listening on the escalation queue for escalations.

close

public void close()

Description copied from interface: Service

closes all opened resources

Specified by:

close in interface Service

doRequest

public int doRequest(Event req,
                     int timeout)

It processes the request according to the preconfigured rulesets. If timeout is less than zero, there is no wait. If timeout is larger than zero, it will wait for the processed event until timeout. If timeout is zero, it blocks until the processed event is done. It returns 1 for success, 0 for timeout and -1 for failure. All the requests will be routed to adminServer via the outlink of escalation. The method is MT-Safe.

N.B., The input request will be modified for the response.

Specified by:

doRequest in interface Service

keepRunning

public boolean keepRunning(XQueue xq)

getName

public java.lang.String getName()

Description copied from interface: Service

returns the name of the service

Specified by:

getName in interface Service

getOperation

public java.lang.String getOperation()

Description copied from interface: Service

returns the string of the operation

Specified by:

getOperation in interface Service

getStatus

public int getStatus()

Description copied from interface: Service

returns the status of the service

Specified by:

getStatus in interface Service

getDebugMode

public int getDebugMode()

Description copied from interface: Service

returns the debug mode of the service

Specified by:

getDebugMode in interface Service

setDebugMode

public void setDebugMode(int debug)

Description copied from interface: Service

sets the debug mode of the service

Specified by:

setDebugMode in interface Service

loadListProperties

public static int loadListProperties(java.util.List list,
                                     java.lang.String configDir,
                                     int show,
                                     java.util.Map props)

It loads the property map from configDir for each string item of the given list and adds the property map to the given props. It only supports the config files with the extension of ".json". It returns the number of included configs upon success or -1 otherwise.

loadIncludedProperties

public static int loadIncludedProperties(java.util.List group,
                                         java.lang.String cfgDir,
                                         int show,
                                         java.util.Map props,
                                         java.util.Map policy)

It checks the loaded primay include on its ClassName for each string item of the given group. If its classname is defined as a key in the given policy map for 2nd includes, the value will be the name of the list that may contain items to be included secondarily. For each item to be included, the method will load its property map from cfgDir and merges it to its primary include loaded already to props. It only supports the config files with the extension of ".json". It returns the number of merged configs upon success or -1 otherwise.

query

public static java.lang.String query(MessagePersister pstr,
                                     javax.jms.Message msg)

sends a query message via the given persister and waits for response. It returns null if sucessful. Otherwise, error message is returned. This method is not efficient at all. It is supposed to be used for ad hoc request. The persister has to be fully initialized. The most of the persisters only support TextMessage or BytesMessage.

main

public static void main(java.lang.String[] args)

The configuration parameters are stored in the property file, Agent.json, that lists all monitorGroups, etc.

Usage: java org.qbroker.flow.MonitorAgent [-?|-l|-I ConfigFile|...]

Parameters:

args - the command line arguments