logging: Example That Sets Up Different Logging Levels

The logging quickstart demonstrates how to configure different logging levels in WildFly.

What is it?

The logging quickstart demonstrates how to set up and log different levels of information in WildFly Application Server.

This quickstart contains contains a simple REST endpoint which will log messages. The index.html page can be used to log messages and see the results. However, you could use a REST client or something like cURL to invoke log messages.

To better visualize how the logging configuration works, you first deploy and access the application before configuring the logs and view the resulting log files. Then you configure the logs, redeploy and access the application, and look at the log files again to see the differences.

Browse the source

System Requirements

The application this project produces is designed to be run on WildFly Application Server 32 or later.

All you need to build this project is Java 11.0 (Java SDK 11) or later and Maven 3.6.0 or later. See Configure Maven to Build and Deploy the Quickstarts to make sure you are configured correctly for testing the quickstarts.

Use of the WILDFLY_HOME and QUICKSTART_HOME Variables

In the following instructions, replace WILDFLY_HOME with the actual path to your WildFly installation. The installation path is described in detail here: Use of WILDFLY_HOME and JBOSS_HOME Variables.

When you see the replaceable variable QUICKSTART_HOME, replace it with the path to the root directory of all of the quickstarts.

Back Up the WildFly Standalone Server Configuration

Before you begin, back up your server configuration file.

If it is running, stop the WildFly server.
Back up the WILDFLY_HOME/standalone/configuration/standalone.xml file.

After you have completed testing this quickstart, you can replace this file to restore the server to its original configuration.

Start the WildFly Standalone Server

Open a terminal and navigate to the root of the WildFly directory.
Start the WildFly server with the default profile by typing the following command.
```
$ WILDFLY_HOME/bin/standalone.sh 
```
Note
For Windows, use the WILDFLY_HOME\bin\standalone.bat script.

Build and Deploy the Quickstart

Make sure WildFly server is started.
Open a terminal and navigate to the root directory of this quickstart.
Type the following command to build the quickstart.
```
$ mvn clean package
```
Type the following command to deploy the quickstart.
```
$ mvn wildfly:deploy
```

This deploys the jboss-logging/target/jboss-logging.war to the running instance of the server.

You should see a message in the server log indicating that the archive deployed successfully.

Access the Application

The application is running at the following URL: http://localhost:8080/jboss-logging/.

You will see the following message in the server console:

18:20:33,272 FATAL [org.jboss.as.quickstarts.logging.rest.LogListingResource] (default task-1) This is an FATAL message from 127.0.0.1:50130
18:20:34,530 ERROR [org.jboss.as.quickstarts.logging.rest.LogListingResource] (default task-1) This is an ERROR message from 127.0.0.1:50130
18:20:35,332 WARN  [org.jboss.as.quickstarts.logging.rest.LogListingResource] (default task-1) This is an WARN message from 127.0.0.1:50130
18:20:36,254 INFO  [org.jboss.as.quickstarts.logging.rest.LogListingResource] (default task-1) This is an INFO message from 127.0.0.1:50130
18:20:37,156 DEBUG [org.jboss.as.quickstarts.logging.rest.LogListingResource] (default task-1) This is an DEBUG message from 127.0.0.1:50130
18:20:38,003 TRACE [org.jboss.as.quickstarts.logging.rest.LogListingResource] (default task-1) This is an TRACE message from 127.0.0.1:50130

Check the Server Logs

The log files are located in the WILDFLY_HOME/standalone/log log directory. At this point you should see the following log files.

server.log - This is the standard log produced by the application server. By default, it contains all the server log messages, including the server startup messages.

Configure the Server

Now you have deployed the quickstart with the default configuration, you run a management CLI script to configure the logging subsystem and review the differences in the resulting log files.

Before you begin, make sure you do the following:
- Back up the WildFly standalone server configuration as described above.
- Start the WildFly server with the standalone default profile as described above.
Review the configure-logging.cli file in the root of this quickstart directory. This script configures the logging subsystem in the server configuration file. It configures the file handlers, creates the logger for our quickstart and sets the level to TRACE. It also assigns the handlers for our quickstart to our logger.
Open a new terminal, navigate to the root directory of this quickstart, and run the following command, replacing WILDFLY_HOME with the path to your server:
```
$ WILDFLY_HOME/bin/jboss-cli.sh --connect --file=configure-logging.cli
```
Note
For Windows, use the WILDFLY_HOME\bin\jboss-cli.bat script.

You should see the following result when you run the script:
```
The batch executed successfully
```

Test the New Logging Configuration

Make sure you start the WildFly server with the standalone default profile as described above.
Build and deploy the quickstart.
Access the application.

Recheck the Server Logs

The log files are located in the WILDFLY_HOME/standalone/log log directory. You should now see the 6 additional log files that are produced by this quickstart. They are listed below in hierarchical order from the largest file containing the most messages to the smallest file containing the least messages.

quickstart.trace.log
quickstart.debug.log
quickstart.info.log
quickstart.warn.log
quickstart.error.log
quickstart.fatal.log

The following are the rest endpoint paths. Note these can be accessed from the index.html by clicking the buttons

/api/logs/trace
/api/logs/debug
/api/logs/info
/api/logs/warn
/api/logs/error
/api/logs/fatal

The following describes what happens when you access this quickstart:

When you access one of the above endpoints, a simple message is logged.
Finally, the class file logs various levels, each to its own file as configured in standalone.xml. Note that log levels are hierarchical. When set, all log levels above the specified level are logged as well.

Common uses of the 6 log levels are outlined below. You should use the level that makes the most sense in your environment.

FATAL - Used to track critical system failures.  When this log message is written, it is writing application error that has caused service to cease.  This is the most narrow logging.
ERROR - Used to track application errors that may cause one request to fail (not a service ceasement).
WARN -  Used for warnings. At this level, all *WARN*, *ERROR*, and *FATAL* messages are written. Use this level message  as a predictive measure for possible forthcoming issues.
INFO -  This provides any information - state transition, object values, etc
DEBUG - Turned on in any environment when a problem is occuring.  The information captured may be throughput, communication, object values, etc.
TRACE - Turned on in any environment where you are trying to follow an execution path, for optimization or debugging.  This is the most broad logging level and all messages are written.

To view log file differences for different logging levels, change the level for the "org.jboss.as.quickstarts.logging" logger from TRACE to DEBUG, INFO, WARN, ERROR, or FATAL, then access the application.

Run the Integration Tests

This quickstart includes integration tests, which are located under the src/test/ directory. The integration tests verify that the quickstart runs correctly when deployed on the server.

Follow these steps to run the integration tests.

Make sure WildFly server is started.
Make sure the quickstart is deployed.
Type the following command to run the verify goal with the integration-testing profile activated.
```
$ mvn verify -Pintegration-testing 
```

Undeploy the Quickstart

When you are finished testing the quickstart, follow these steps to undeploy the archive.

Make sure WildFly server is started.
Open a terminal and navigate to the root directory of this quickstart.
Type this command to undeploy the archive:
```
$ mvn wildfly:undeploy
```

Restore the WildFly Standalone Server Configuration

You can restore the original server configuration using either of the following methods.

You can run the remove-logging.cli script provided in the root directory of this quickstart.
You can manually restore the configuration using the backup copy of the configuration file.

Restore the WildFly Standalone Server Configuration by Running the JBoss CLI Script

Start the WildFly server as described above.
Open a new terminal, navigate to the root directory of this quickstart, and run the following command, replacing WILDFLY_HOME with the path to your server:
```
$ WILDFLY_HOME/bin/jboss-cli.sh --connect --file=remove-logging.cli
```
Note
For Windows, use the WILDFLY_HOME\bin\jboss-cli.bat script.

This script removes the log and file handlers from the logging subsystem in the server configuration. You should see the following result when you run the script:

{"outcome" => "success"}
{"outcome" => "success"}
{"outcome" => "success"}
{"outcome" => "success"}
{"outcome" => "success"}
{"outcome" => "success"}
{"outcome" => "success"}

Restore the WildFly Standalone Server Configuration Manually

When you have completed testing the quickstart, you can restore the original server configuration by manually restoring the backup copy the configuration file.

If it is running, stop the WildFly server.
Replace the WILDFLY_HOME/standalone/configuration/standalone.xml file with the backup copy of the file.

Building and running the quickstart application with provisioned WildFly server

Instead of using a standard WildFly server distribution, you can alternatively provision a WildFly server to deploy and run the quickstart, by activating the Maven profile named provisioned-server when building the quickstart:

$ mvn clean package -Pprovisioned-server

The provisioned WildFly server, with the quickstart deployed, can then be found in the target/server directory, and its usage is similar to a standard server distribution, with the simplification that there is never the need to specify the server configuration to be started.

The server provisioning functionality is provided by the WildFly Maven Plugin, and you may find its configuration in the quickstart pom.xml:

        <profile>
            <id>provisioned-server</id>
            <build>
                <plugins>
                    <plugin>
                        <groupId>org.wildfly.plugins</groupId>
                        <artifactId>wildfly-maven-plugin</artifactId>
                        <configuration>
                            <feature-packs>
                                <feature-pack>
                                    <location>org.wildfly:wildfly-galleon-pack:${version.server}</location>
                                </feature-pack>
                            </feature-packs>
                            <layers>...</layers>
                            <!-- deploys the quickstart on root web context -->
                            <name>ROOT.war</name>
                        </configuration>
                        <executions>
                            <execution>
                                <goals>
                                    <goal>package</goal>
                                </goals>
                            </execution>
                        </executions>
                    </plugin>
                    ...
                </plugins>
            </build>
        </profile>

Note	Since the plugin configuration above deploys quickstart on root web context of the provisioned server, the URL to access the application should not have the `/jboss-logging` path segment after `HOST:PORT`.

Run the Integration Tests with a provisioned server

The integration tests included with this quickstart, which verify that the quickstart runs correctly, may also be run with a provisioned server.

Follow these steps to run the integration tests.

Make sure the server is provisioned.

$ mvn clean package -Pprovisioned-server

Start the WildFly provisioned server, this time using the WildFly Maven Plugin, which is recommended for testing due to simpler automation. The path to the provisioned server should be specified using the jbossHome system property.
```
$ mvn wildfly:start -DjbossHome=target/server 
```
Type the following command to run the verify goal with the integration-testing profile activated, and specifying the quickstart’s URL using the server.host system property, which for a provisioned server by default is http://localhost:8080.
```
$ mvn verify -Pintegration-testing -Dserver.host=http://localhost:8080 
```
Shutdown the WildFly provisioned server, this time using the WildFly Maven Plugin too.
```
$ mvn wildfly:shutdown
```

Building and running the quickstart application with OpenShift

Build the WildFly Source-to-Image (S2I) Quickstart to OpenShift with Helm Charts

On OpenShift, the S2I build with Apache Maven uses an openshift Maven profile to provision a WildFly server, deploy and run the quickstart in OpenShift environment.

The server provisioning functionality is provided by the WildFly Maven Plugin, and you may find its configuration in the quickstart pom.xml:

        <profile>
            <id>openshift</id>
            <build>
                <plugins>
                    <plugin>
                        <groupId>org.wildfly.plugins</groupId>
                        <artifactId>wildfly-maven-plugin</artifactId>
                        <configuration>
                            <feature-packs>
                                <feature-pack>
                                    <location>org.wildfly:wildfly-galleon-pack:${version.server}</location>
                                </feature-pack>
                                <feature-pack>
                                    <location>org.wildfly.cloud:wildfly-cloud-galleon-pack:${version.pack.cloud}</location>
                                </feature-pack>
                            </feature-packs>
                            <layers>...</layers>
                            <name>ROOT.war</name>
                        </configuration>
                        <executions>
                            <execution>
                                <goals>
                                    <goal>package</goal>
                                </goals>
                            </execution>
                        </executions>
                    </plugin>
                    ...
                </plugins>
            </build>
        </profile>

You may note that unlike the provisioned-server profile it uses the cloud feature pack which enables a configuration tuned for OpenShift environment.

Getting Started with WildFly for OpenShift and Helm Charts

This section contains the basic instructions to build and deploy this quickstart to WildFly for OpenShift or WildFly for OpenShift Online using Helm Charts.

Prerequisites

You must be logged in OpenShift and have an oc client to connect to OpenShift
Helm must be installed to deploy the backend on OpenShift.

Once you have installed Helm, you need to add the repository that provides Helm Charts for WildFly.

$ helm repo add wildfly https://docs.wildfly.org/wildfly-charts/
"wildfly" has been added to your repositories
$ helm search repo wildfly
NAME                    CHART VERSION   APP VERSION     DESCRIPTION
wildfly/wildfly         ...             ...            Build and Deploy WildFly applications on OpenShift
wildfly/wildfly-common  ...             ...            A library chart for WildFly-based applications

Deploy the WildFly Source-to-Image (S2I) Quickstart to OpenShift with Helm Charts

Log in to your OpenShift instance using the oc login command. The backend will be built and deployed on OpenShift with a Helm Chart for WildFly.

Navigate to the root directory of this quickstart and run the following command:

$ helm install jboss-logging -f charts/helm.yaml wildfly/wildfly --wait --timeout=10m0s
NAME: jboss-logging
...
STATUS: deployed
REVISION: 1

This command will return once the application has successfully deployed. In case of a timeout, you can check the status of the application with the following command in another terminal:

oc get deployment jboss-logging

The Helm Chart for this quickstart contains all the information to build an image from the source code using S2I on Java 17:

Unresolved directive in ../shared-doc/helm-deploy-project.adoc - include::/home/runner/work/quickstart/quickstart/logging/charts/helm.yaml[]

This will create a new deployment on OpenShift and deploy the application.

If you want to see all the configuration elements to customize your deployment you can use the following command:

$ helm show readme wildfly/wildfly

Get the URL of the route to the deployment.

$ oc get route jboss-logging -o jsonpath="{.spec.host}"

Access the application in your web browser using the displayed URL.

Note	The Maven profile named `openshift` is used by the Helm chart to provision the server with the quickstart deployed on the root web context, and thus the application should be accessed with the URL without the `/jboss-logging` path segment after `HOST:PORT`.

Run the Integration Tests with OpenShift

The integration tests included with this quickstart, which verify that the quickstart runs correctly, may also be run with the quickstart running on OpenShift.

Note	The integration tests expect a deployed application, so make sure you have deployed the quickstart on OpenShift before you begin.

Run the integration tests using the following command to run the verify goal with the integration-testing profile activated and the proper URL:

$ mvn verify -Pintegration-testing -Dserver.host=https://$(oc get route jboss-logging --template='{{ .spec.host }}')

Note	The tests are using SSL to connect to the quickstart running on OpenShift. So you need the certificates to be trusted by the machine the tests are run from.

Undeploy the WildFly Source-to-Image (S2I) Quickstart from OpenShift with Helm Charts

$ helm uninstall jboss-logging