Apache River

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  1. 4f7b49b Readme.md now has slightly better formatting. by Greg Trasuk · 3 years, 8 months ago master
  2. 3e9b953 Readme.md now has slightly better formatting. by Greg Trasuk · 3 years, 8 months ago
  3. 496e36f Readme.md now contains a "First Fifteen Minutes" guide to building and running the container and a 'hello-world' example. by Greg Trasuk · 3 years, 8 months ago plugin-work
  4. 33855de Admin Service is able to query all the ApplicationManager objects in the container context for application statuses. by Greg Trasuk · 3 years, 8 months ago
  5. e6828db ContextualWorkManager has been changed over to present a ScheduledExecutorService for applications to use, rather than a WorkManager. by Greg Trasuk · 3 years, 9 months ago

river-container

This project is the initial development of the Apache River Container. It is not yet released as Apache Software. Use at your own risk, and please post comments to dev@river.apache.org.

The First Fifteen Minutes

Let‘s assume you’ve managed to download the source from git. In fact, let‘s assume that you’re reasonably conversant with git, so you can pull the examples project below.

Before You Start

You'll need Maven 3.x installed, such that you can run ‘mvn’ from the command line.

Build From Source

This step may not be required in the future, since you'll be able to download a convenience binary once the project is released

Go to the root of the river-container download, and type

mvn clean install

Run the default container profile

cd product/target/product*
bin/run 

The steps above will startup a default container that has instances of the service registrar (Reggie) and the transaction manager (Mahalo). All services are registered in a workgroup called ‘RiverContainerDefault’.

Run the service browser

Open a new command line window in the root of the river-container download, then do the following:

cd product/target/product*
bin/run client browser

You'll see a service browser window open up. It should show one registrar. Select the registrar. You should now see the infrastructure services, Reggie and Mahalo. Leave the service browser running while we start up a “Hello-world” service, below.

Compile a “Hello-World” Service

Maybe the ‘hello-world’ example should be included in the container deliverable? Please comment on ‘dev@river.apache.org’. Eventually, we should be able to create this example service using a Maven archetype.

Using git, pull the examples from https://github.com/trasukg/river-container-examples.

‘cd’ into your hello-example' directory, and then:

mvn clean install

Deploy and run the “Hello-World” Service

When Maven is done, you should be able to see the finished service archive, ‘hello-module/target/hello-module-1.0-SNAPSHOT.jar’

Copy that ‘jar’ file into the ‘profiles/default/deploy’ folder inside our ‘river-container/product/target/product*’ folder.

Eventually, we'll have a maven plugin that does this, so you can just do ‘mvn river:deploy’ rather than copying it manually.

If you left the container running, you should see some output indicating that the service is being deployed. If you didn't leave the container running, start it up now.

You should also see the service in the service browser, with the interface ‘org.apache.river.container.hello.example.api.Greeter’

Deploy and Run the “Hello-World” Consumer

When Maven finished above, it also created a client archive, ‘hello-client-module/target/hello-client-module-1.0-SNAPSHOT.jar’

Copy that ‘jar’ file into the ‘profiles/client/deploy’ folder inside our ‘river-container/product/target/product*’ folder.

Open a new command line window in the root of the river-container download, then do the following:

cd product/target/product*
bin/run client hello-client

The client starts up, and eventually prompts ‘Please enter your name’. Enter your name and then press return.

The client sends the greeter service a message, then prints out the reply.

Use the Network!

If you have another machine on the local area network, and if the network is configured to allow multicast, you should be able to run the browser and the hello-client on a different machine.

That concludes the ‘First Fifteen Minutes’ demo. Below, there is a little more detailed information...

Building from Source

mvn clean install

Running Services in the Container

cd product/target/product*
bin/run [profile] arg*

If you don‘t specify [profile] the ‘default’ profile will be used. ‘arg*’ isn’t really used much in the service container profiles (like ‘default’).

Services are packaged into a jar file and placed into the ‘deploy’ folder of the profile that you want to run. When you run the container, all services in the profile are started up. The default profile monitors the deploy folder each 5s and starts up any new services you put into the deploy folder. The ‘default’ profile already includes a transient reggie instance and a transient mahalo instance. You can add your own services to this folder as well.

Have a look at the ‘reggie-module’ or ‘mahalo-module’ target folders to see what the archive should look like. Startup parameters are in ‘start.properties’. ‘start.properties’ calls out the startup class and the parameters to its constructor (typically the name of the configuration file and any overrides to the config).

Running Client Applications

cd product/target/product*
bin/run client AppName arg*

Starts up the container using the ‘client’ profile, which then starts the client that is named by ‘AppName’ (and only that client, no matter if there are multiple apps in the deploy folder).

The container will host client applications, making the downloads available via a codebase server, and setting up all the security polices that are required. Client apps are packaged much like the services mentioned above.

Service Browser

cd product/target/product*
bin/run client browser

Starts up the service browser.

Sample Service

Reggie-module and mahalo-module might be interesting samples. For a simpler ‘hello-world’ example with a Maven build, see https://github.com/trasukg/river-container-examples.