QCG-Notification Installation

QCG-Notification requires the  QCG-Core library to be installed (generally it is enough to use the QCG-Core library compilled and installed in a default fashion, but in specific scenarios, additional parameters to the QCG-Core's ./configure script may be needed). If this prerequisite is fulfilled the QCG-Notification may be installed from  sources in a few simple steps:

tar xf qcg-ntf-latest.tar
cd qcg-ntf-2.0.0
./configure --prefix=/opt/qcg --with-qcg-core=/opt/qcg
make
sudo make install

In order to verify later the installation, it is recommended to provide an additional option to ./configure: --with-consumer

Configuration

Before you start you need to create a new system user (e.g. qcg-ntf) that will be used to start the service:

useradd -d  /opt/qcg/var/log/qcg-ntf/ -M  qcg-ntf

Give the qcg-ntf user ownership of the log directory:

chown qcg-ntf /opt/qcg/var/log/qcg-ntf/

Service configuration

Minimal configuration requires only the host and port to be apropriately changed in the main service configuration file: PREFIX/etc/qcg-ntfd.xml. In such a basic configuration you should also set <smn:DatabaseEnabled> to false.

Although it is optional, the database may be enabled and configured to realize more advanced notification scenarios as well as support recovery of the notification objects (such as subscriptions) after the service restart.

Database configuration

The easiest way to setup QCG-Notification database is use of provided script located in PREFIX/share/qcg-ntf/tools/ direcotory:

/opt/qcg/share/qcg-ntf/tools/qcg-ntf-install.sh
Welcome to qcg-ntf installation script!

This script will guide you through process of configuring proper environment
for running the QCG-Notification service. You have to answer few questions regarding
parameters of your database. If you are not sure just press Enter and use the
default values.
  
Use local PostgreSQL server? (y/n) [y]: y
Database [qcg-ntf]: 
User [qcg-ntf]: 
Password [qcg-ntf]: MojeTajneHaslo
Create database? (y/n) [y]: y
Create user? (y/n) [y]: y
  
Checking for system user qcg-ntf...OK
Checking whether PostgreSQL server is installed...OK
Checking whether PostgreSQL server is running...OK
  
Performing installation
* Creating user qcg-ntf...OK
* Creating database qcg-ntf...OK
* Creating database schema...OK
* Checking for ODBC data source qcg-ntf...
* Installing ODBC data source...OK
    
Remember to add appropriate entry to /var/lib/pgsql/data/pg_hba.conf (as the first rule!) to allow user qcg-ntf to
access database qcg-ntf. For instance:
  
host    qcg-ntf       qcg-ntf       127.0.0.1/32    md5
  
and reload Postgres server.

The complete configuration guide can be found in the PREFIX/share/qcg-ntf/doc/ directory.

Starting the service

As the qcg-ntf user type:

/opt/qcg/sbin/qcg-ntfd

or if you want the service not to daemonize and print all logs to console type:

/opt/qcg/sbin/qcg-ntfd -d

otherwise the logs can be found in /opt/qcg/var/log/qcg-ntf/qcg-ntfd.log.

Stopping the service

The service is stopped by sending SIGTERM signal, e.g.:

pkill qcg-ntfd

Verifying the installation

If the service was configured with the option --with-consumer attached to ./configure, the basic verification scenario may be proceeded in a following way:

1. Set the Host and Port parameters in the configuration files of the QCG-Notification service and sample consumer, respectivetly in /opt/qcg/etc/qcg-ntfd.xml and /opt/qcg/etc/qcg-ntf-consumer.xml. For example, the key part of the qcg-ntfd.xml file may looks as foolows:

   <sm:Module xsi:type="sm:ecm_gsoap.service">
       <sm:Host>127.0.0.1</sm:Host>
       <sm:Port>2211</sm:Port>
       ...
   </sm:Module>
   

   Similarly, the part of qcg-ntf-consumer.xml may have a following form:

   <sm:Module xsi:type="sm:ecm_gsoap.service">
       <sm:Host>127.0.0.1</sm:Host>
       <sm:Port>2212</sm:Port>
       ...
   </sm:Module>
   

2. Start the qcg-ntfd in a debug mode:

   /opt/qcg/sbin/qcg-ntfd -d
   

3. Start the qcg-ntf-consumer in a debug mode:

   /opt/qcg/sbin/qcg-ntf-consumer -d
   

4. Using the sample client program create a subscription in the QCG-Notification service:

   ./qcg-ntf-client -d -u http://127.0.0.1:2211 -S "cons=http://127.0.0.1:2212 top=http://schemas.qoscosgrid.org/comp/2011/04/notification/topic;//*;Full"
   ...
   INF May 17 14:15:51 1128       0xa0262720 [qcg-client-gsoa] Subscribed, subRef: '810917963'
   ...
   

   Note: The created subscription assigns a service running on http://127.0.0.1:2212 to be a consumer of notifications sent on topics from a namespace http://schemas.qoscosgrid.org/comp/2011/04/notification/topic. The subscription id is 810917963

5. Send a sample notification on a some topic from the namespace http://schemas.qoscosgrid.org/comp/2011/04/notification/topic to the QCG-Notification service:

   ./qcg-ntf-client -d -u http://127.0.0.1:2211 -N "top=http://schemas.qoscosgrid.org/comp/2011/04/notification/topic;ActivityState/Queued;Full msg=<SampleNotification/>"
   ...
   INF May 17 14:19:32 1134       0xa0262720 [qcg-client-gsoa] Notification sent successfully
   ...
   

6. Check the output of qcg-ntfd and output of qcg-ntf-consumer. The outputs' scripts, in order, should be simillar to the following ones:

   ...
   INF May 17 14:19:32 1113       0xb0185000 [......ecm_gsoap] Serving Notify routine
   INF May 17 14:19:32 1113       0xb0185000 [...............] Sending message to: 'http://localhost:2212'
   INF May 17 14:19:32 1113       0xb0185000 [...............] Notification forwarded to '1' consumers
   INF May 17 14:19:32 1113       0xb0185000 [...............] Forwarded Notification on topic: 'http://schemas.qoscosgrid.org/comp/2011/04/notification/topic/ActivityState/Queued'
   ...
   

   ...
   INF May 17 14:19:32 1120       0xb0491000 [qcg-consumer-gs] Receive notify message:
   INF May 17 14:19:32 1120       0xb0491000 [qcg-consumer-gs] From:  127.0.0.1
   INF May 17 14:19:32 1120       0xb0491000 [qcg-consumer-gs] Topic: <wsnt:Topic xmlns:tns="http://schemas.qoscosgrid.org/comp/2011/04/notification/topic" xmlns:wsnt="http://docs.oasis-open.org/wsn/b-2" Dialect="http://docs.oasis-open.org/wsn/t-1/TopicExpression/Full">tns:ActivityState/Queued</wsnt:Topic>
   ...
   

7. Finally remove the created subscription:

   ./qcg-ntf-client -d -u http://localhost:2211 -U "id=810917963"
   ...
   INF May 17 14:41:48 3318       0xa0262720 [qcg-client-gsoa] Unsubscribed: '810917963'
   ...
   

Deployment in QosCosGrid

Within QosCosGrid the QCG-Notification service is used for brokering notification messages about job state changes. All instances of the QCG-Computing services acts as the information Producers while the QCG-Broker as the Consumer. In most cases it is enough that only one instance of the QCG-Notification is deployed per Administrative Domain (i.e.: not necessary one per Cluster).

QCG-Computing integration

After finishing the QCG-Notification configuration and having QCG-Computing service installed, you must edit the QCG-Computing service configuration file and update the content of the <ServiceURL> elements (in <Module xsi:type="smc:notification_wsa"> section). For e.g. if in the PREFIX/etc/qcg-ntfd.xml one can find <Host>example.com<Host> and <Port>19005<Port> the <ServiceURL> in PREFIX/etc/qcg-compd.xml must be set to http://example.com:19005/.

Note: You must restart the QCG-Computing service after updating the qcg-compd.xml configuration file.

When you start the QCG-Notification service and update the QCG-Computing configuration try to submit a simple job and check the QCG-Computing log file to see if there are now any error messages on sending notifications, e.g.:

tail -f /opt/qcg/var/log/qcg-comp/qcg-compd.log
INF Sep 17 16:15:01 24201 0x44b22940 [notification_ws] Sending notify message (topic = ActivityState/TerminalState/Finished, activity_id = 0544b24a-e960-400e-4910-f1a893632610, status = Finished)

QCG-Notification installation in PL-Grid

There are available RPM packages for installation QCG-Notification in PL-Grid. For detailed instructions follow this link?.