Chapter 30. Installing and configuring Smart Router
Smart Router (KIE Server router) is a lightweight Java component that you can use as an integration layer between multiple KIE Servers, client applications, and other components. Depending on your deployment and execution environment, Smart Router can aggregate multiple independent KIE Server instances as though they are a single server. Smart Router provides the following features:
- Data aggregation
- Collects data from all KIE Server instances (one instance from each group) when there is a client application request and aggregates the results in a single response.
- Routing
- Functions as a single endpoint that receives calls from client applications to any of your services and routes each call automatically to the KIE Server that runs the specific service. This means that KIE Servers do not need to have the same services deployed.
- Load balancing
- Provides efficient load balancing. Load balancing requests for a Smart Router cluster must be managed externally with standard load balancing tools.
- Authentication
- Authenticates KIE Server instances by using a system property flag and can enable HTTPS traffic.
- Environment Management
- Manages the changing environment, for example adding or removing server instances.
30.1. Load-balancing KIE Server instances with Smart Router Copy linkLink copied to clipboard!
You can use Smart Router to aggregate multiple independent KIE Server instances as though they are a single server. It performs the role of an intelligent load balancer because it can route requests to individual KIE Server instances and aggregate data from different KIE Server instances. Smart Router uses aliases to perform as a proxy.
Prerequisites
Multiple KIE Server instances are installed.
NoteYou do not need to configure KIE Server as unmanaged for Smart Router.
An unmanaged KIE Server instance does not connect to the controller. For example, if you connect an unmanaged KIE Server instance to Smart Router and register Smart Router with the controller, then Business Central contacts the unmanaged KIE Server instance by using Smart Router.
Procedure
Navigate to the Software Downloads page in the Red Hat Customer Portal (login required), and select the product and version from the drop-down options:
- Product: Process Automation Manager
- Version: 7.12
- Download Red Hat Process Automation Manager 7.12.0 Add-Ons.
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Extract the downloaded
rhpam-7.12.0-add-ons.zipfile to a temporary directory. Therhpam-7.12.0-smart-router.jarfile is in the extractedrhpam-7.12.0-add-onsdirectory. -
Copy the
rhpam-7.12.0-smart-router.jarfile to the location where you will run the file. Enter the following command to start Smart Router:
java -Dorg.kie.server.router.host=<ROUTER_HOST> -Dorg.kie.server.router.port=<ROUTER_PORT> -Dorg.kie.server.controller=<CONTROLLER_URL> -Dorg.kie.server.controller.user=<CONTROLLER_USER> -Dorg.kie.server.controller.pwd=<CONTROLLER_PWD> -Dorg.kie.server.router.config.watcher.enabled=true -Dorg.kie.server.router.repo=<NFS_STORAGE> -jar rhpam-7.12.0-smart-router.jarThe properties in the preceding command have the following default values:
org.kie.server.router.host=localhost org.kie.server.router.port=9000 org.kie.server.controller= N/A org.kie.server.controller.user=kieserver org.kie.server.controller.pwd=kieserver1! org.kie.server.router.repo= <CURRENT_WORKING_DIR> org.kie.server.router.config.watcher.enabled=falseorg.kie.server.controlleris the URL of the server controller, for example:org.kie.server.controller=http://<HOST>:<PORT>/controller/rest/controllerorg.kie.server.router.config.watcher.enabledis an optional settings to enable the watcher service system property.NoteInstead of specifying configuration properties in the command line, you can use a configuration file. For information about configuring Smart Router using a file, see Section 30.5, “Configuring Smart Router settings using a configuration file”.
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On every KIE Server instance that must connect to the Smart Router, set the
org.kie.server.routersystem property to the Smart Router URL. To access Smart Router from the client side, use the Smart Router URL instead of the KIE Server URL, for example:
KieServicesConfiguration config = KieServicesFactory.newRestConfiguration("http://smartrouter.example.com:9000", "USERNAME", "PASSWORD");In this example,
smartrouter.example.comis the Smart Router URL, andUSERNAMEandPASSWORDare the log in credentials for the Smart Router configuration.To create a new container in an umanaged KIE Server so that you can fill it with example data, send the following HTTP request:
$ curl -v -X POST -H 'Content-type: application/xml' -H 'X-KIE-Content-Type: xstream' -d @create-container.xml -u ${KIE_CRED} http://${KIE-SERVER-HOST}:${KIE-SERVER-PORT}/kie-server/services/rest/server/config/Review the contents the
create-container.xmlfile:<script> <create-container> <container container-id="example:timer-test:1.1"> <release-id> <group-id>example</group-id> <artifact-id>timer-test</artifact-id> <version>1.1</version> </release-id> <config-items> <itemName>RuntimeStrategy</itemName> <itemValue>PER_PROCESS_INSTANCE</itemValue> <itemType></itemType> </config-items> </container> </create-container> </script>A message about the deployed container is displayed in the Smart Router console. For example:
INFO: Added http://localhost:8180/kie-server/services/rest/server as server location for container example:timer-test:1.1To display a list of containers, enter the following command:
$ curl http://localhost:9000/mgmt/listThe list of containers is displayed:
{ "containerInfo": [{ "alias": "timer-test", "containerId": "example:timer-test:1.1", "releaseId": "example:timer-test:1.1" }], "containers": [ {"example:timer-test:1.1": ["http://localhost:8180/kie-server/services/rest/server"]}, {"timer-test": ["http://localhost:8180/kie-server/services/rest/server"]} ], "servers": [ {"kieserver2": []}, {"kieserver1": ["http://localhost:8180/kie-server/services/rest/server"]} ] }To initiate a process using the Smart Router URL, enter the following command:
$ curl -s -X POST -H 'Content-type: application/json' -H 'X-KIE-Content-Type: json' -d '{"timerDuration":"9s"}' -u kieserver:kieserver1! http://localhost:9000/containers/example:timer-test:1.1/processes/timer-test.TimerProcess/instances
30.2. Configuring Smart Router for TLS support Copy linkLink copied to clipboard!
You can configure Smart Router (KIE Server Router) for Transport Layer Security (TLS) support to allow HTTPS traffic. In addition, you can disable unsecure HTTP connections to Smart Router.
Prerequisites
- KIE Server is installed on each node of a Red Hat JBoss EAP 7.4 cluster.
- Smart Router is installed and configured. For more information, see Section 30.1, “Load-balancing KIE Server instances with Smart Router”.
Procedure
To start Smart Router, use one of the following methods:
To start Smart Router with TLS support and HTTPS enabled as well as allowing HTTP connections, enter the following command:
java -Dorg.kie.server.router.tls.keystore = <KEYSTORE_PATH> -Dorg.kie.server.router.tls.keystore.password = <KEYSTORE_PASSWORD> -Dorg.kie.server.router.tls.keystore.keyalias = <KEYSTORE_ALIAS> -Dorg.kie.server.router.tls.port = <HTTPS_PORT> -jar rhpam-7.12.0-smart-router.jarIn this example, replace the following variables:
-
<KEYSTORE_PATH>: The path where the keystore will be stored. -
<KEYSTORE_PASSWORD>: The keystore password. -
<KEYSTORE_ALIAS>: The alias name used to store the certificate. -
<HTTPS_PORT>: The HTTPS port. The default HTTPS port is9443. To start Smart Router with TLS support and HTTPS enabled and with HTTP connections disabled, enter the following command:
java -Dorg.kie.server.router.tls.keystore = <KEYSTORE_PATH> -Dorg.kie.server.router.tls.keystore.password = <KEYSTORE_PASSWORD> -Dorg.kie.server.router.tls.keystore.keyalias = <KEYSTORE_ALIAS> -Dorg.kie.server.router.tls.port = <HTTPS_PORT> -Dorg.kie.server.router.port=0 -jar rhpam-7.12.0-smart-router.jarWhen the
org.kie.server.router.portsystem property is set to0, then the HTTP listener is not registered. If TLS is configured and the HTTP listener is not registered, then Smart Router listens only on the HTTPS port.NoteIf TLS is not configured and you disable HTTP by setting
org.kie.server.router.portto0, then an error occurs and Smart Router stops.
30.3. Configuring Smart Router for endpoint authentication Copy linkLink copied to clipboard!
You can configure Smart Router (KIE Server Router) for endpoint authentication.
Prerequisites
- KIE Server is installed on each node of a Red Hat JBoss EAP 7.4 cluster.
- Smart Router is installed and configured. For more information, see Section 30.1, “Load-balancing KIE Server instances with Smart Router”.
Procedure
To start Smart Router with endpoint authentication enabled, configure the management credentials:
Add the following properties to your KIE Server configuration:
`org.kie.server.router.management.username` `org.kie.server.router.management.password`The default
usernameis the KIE Server ID.Add the following property to your Smart Router configuration:
`org.kie.server.router.management.password`The
passwordproperty values aretrueorfalse(default).
NoteEnabling endpoint authentication means any any operation that lists, adds or removes containers must be authenticated.
Optional: Add users to Smart Router. For example:
java -jar rhpam-7.12.0-smart-router.jar -addUser <USERNAME> <PASSWORD>Optional: Remove users from Smart Router. For example:
java -jar rhpam-7.12.0-smart-router.jar -removeUser <USERNAME>
30.4. Configuring Smart Router behavior Copy linkLink copied to clipboard!
In a clustered environment with multiple KIE Servers, the default behavior is to send requests to each KIE Server in parallel and a host of each KIE Server is sent the request using the "round-robin" method. In the following example environment, each KIE Server is deployed with the same KJAR but each KJAR version is different:
| Server Name | KJAR version | Hosts |
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If you send a request, the request is sent to kie-server1 (129.0.1.2), kie-server2 (129.0.2.3), and kie-server3 (129.0.3.1).
If you send a second request, that request is sent to the next host of each KIE Server. For example, kie-server1 (129.0.1.3), kie-server2 (129.0.2.1), and kie-server3 (129.0.3.2).
Smart Router has three components that you can modify to change this behavior:
- ContainerResolver
- The component responsible for finding the container id to use when interacting with servers.
- RestrictionPolicy
- The component responsible for disallowing Smart Router to use specific endpoints.
- ConfigRepository
- The component responsible for maintaining the Smart Router configuration. This is mainly related to the routing table.
- IdentityService
- The component responsible for allowing you to use your own identity provider. This is for KIE Server instances.
Smart Router uses the ServiceLoader utility to implement these components:
- ContainerResolver
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META-INF/services/org.kie.server.router.spi.ContainerResolver - RestrictionPolicy
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META-INF/services/org.kie.server.router.spi.RestrictionPolicy - ConfigRepository
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META-INF/services/org.kie.server.router.spi.ConfigRepository - IdentityService
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META-INF/services/org.kie.server.router.identity.IdentityService
For example, for the above scenario, you can customize the ContainerResolver to make Smart Router search for the latest version of the KJAR process across all available KIE Servers and to always start with that process. This scenario would mean that each KIE Server hosts a single KJAR and each version will share the same alias.
Since Smart Router is an executable jar, to include extensions, you need to modify the command. For example:
java -cp LOCATION/router-ext-7.12.0.redhat-00008.jar:rhpam-7.12.0-smart-router.jar org.kie.server.router.KieServerRouter
Once the service is started you will see log output stating the implementation that is used for the components:
Mar 01, 2017 1:47:10 PM org.kie.server.router.KieServerRouter <init>
INFO: KIE Server router repository implementation is InMemoryConfigRepository
Mar 01, 2017 1:47:10 PM org.kie.server.router.proxy.KieServerProxyClient <init>
INFO: Using 'LatestVersionContainerResolver' container resolver and restriction policy 'ByPassUserNotAllowedRestrictionPolicy'
Mar 01, 2017 1:47:10 PM org.xnio.Xnio <clinit>
INFO: XNIO version 3.3.6.Final
Mar 01, 2017 1:47:10 PM org.xnio.nio.NioXnio <clinit>
INFO: XNIO NIO Implementation Version 3.3.6.Final
Mar 01, 2017 1:47:11 PM org.kie.server.router.KieServerRouter start
INFO: KieServerRouter started on localhost:9000 at Wed Mar 01 13:47:11 CET 2017
30.5. Configuring Smart Router settings using a configuration file Copy linkLink copied to clipboard!
Instead of configuring Smart Router settings in the command line, you can use a configuration file. In this case, settings, including any passwords, are not visible in the command line terminal and server logs.
Procedure
Create a configuration file. This file can contain any number of lines in the
property=valueformat.The file can include any of the following properties. All of the properties are optional.
Expand Table 30.2. Supported properties in the Smart Router configuration file Property name Description Default value org.kie.server.router.idIdentifier of the Smart Router, for identification to other components.
N/A
org.kie.server.router.nameName of the Smart Router, for identification to other components.
N/A
org.kie.server.router.hostThe host name for the machine that runs the Smart Router
localhostorg.kie.server.router.portThe port for incoming HTTP connections. If you configure TLS connections, you can set this property to
0to disable HTTP connections.9000org.kie.server.router.url.externalThe external URL for access to the Smart Router
N/A
org.kie.server.router.tls.portThe port for incoming TLS connections
N/A
org.kie.server.router.tls.keystoreThe keystore file for TLS connections
N/A
org.kie.server.router.tls.keystore.passwordThe password for the keystore for TLS connections
N/A
org.kie.server.router.tls.keystore.keyaliasThe alias name that refers to the TLS certificate in the keystore
N/A
org.kie.server.router.repoThe directory for storing the current repository
The current working directory
org.kie.router.identity.providerThe optional custom provider class for authenticating KIE Server instances with Smart Router. This class must implement the
org.kie.server.router.identity.IdentityManagerinterface, For the source code of this interface, see the GitHub repository.N/A
org.kie.server.controllerThe URL for connecting to the controller
N/A
org.kie.server.controller.userThe user name for connecting to the controller
kieserverorg.kie.server.controller.pwdThe password for connecting to the controller
kieserver1!org.kie.server.controller.tokenThe authentication token for connecting to the controller
N/A
org.kie.server.controller.retry.intervalThe interval, in seconds, for retrying connection to the controller if it failed
10
org.kie.server.controller.retry.limitThe maximum number of retries for connection to the controller if it failed
infinite
org.kie.server.router.config.watcher.enabledIf set to
true, Smart Router periodically scans the configuration file and applies any changesfalseorg.kie.server.router.config.watcher.intervalThe interval, in seconds, for rescanning the configuration file
5
org.kie.server.router.management.passwordIf set to
true, Smart Router requires a password to authenticate a connection from KIE ServerfalseStart Smart Router using the following command line:
java -Dorg.kie.server.router.config.file=<CONFIG_FILE> -jar rhpam-7.12.0-smart-router.jarReplace
<CONFIG_FILE>with the name of the configuration file.