examples/karaf-war-example/README.md

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# Apache Karaf WAR Example

## Abstract

As a polymorphic runtime, Apache Karaf is able to deploy and run lot of different kind of applications.

It's especially possible to deploy a web application packaged as a war, as you can do in any web container.

This example shows how to create a regular war to be deployed in Apache Karaf.

## Artifacts

* `karaf-war-example-webapp` is a regular simple war.
* `karaf-war-example-features` provides a Karaf features repository used for deployment.

## Build 

Simply use:

```
mvn clean install
```

## Feature and Deployment

You have three ways to deploy the example war.

1. Using the war deployer
2. Using the bundle:install shell command (with webbundle protocol)
3. Using the provided feature

### WAR deployer

The WAR deployer allows you to directly hotdeploy war files, by simpling dropping the war files in the Karaf `deploy` folder.

To enable the WAR deployer, you have to install the `war` feature first:

```
karaf@root()> feature:install war
```

Then, simply drop the war file in the `deploy` folder:

```
$ cp examples/karaf-war-example/karaf-war-example-webapp/target/karaf-war-example-webapp-*.war $KARAF_HOME/deploy
```

You can then see the webapp deployed using the `web:list` command:

```
karaf@root()> web:list
ID  │ State       │ Web-State   │ Level │ Web-ContextPath           │ Name
────┼─────────────┼─────────────┼───────┼───────────────────────────┼──────────────────────────
102 │ Active      │ Deployed    │ 80    │ /karaf-war-example-webapp │ karaf-war-example-webapp
```

You can point your browser to [http://localhost:8181/karaf-war-example-webapp].

### Shell command (webbundle)

You can also install the war directly from a location using the "classic" `bundle:install` command.
As a war is not a "regular" bundle, we need to use the `webbundle` protocol to specify the artifact is actually a war.

First, we install the `war` feature which provides the `webbundle` protocol:

```
karaf@root()> feature:install war
```

Then, we can directly install a war from any location, for instance:

```
karaf@root()> bundle:install -s webbundle:mvn:org.apache.karaf.examples/karaf-war-example-webapp/4.3.0-SNAPSHOT/war?Web-ContextPath=example
```

You can see the war deployed using `web:list` command:

```
karaf@root()> web:list
ID  │ State       │ Web-State   │ Level │ Web-ContextPath │ Name
────┼─────────────┼─────────────┼───────┼─────────────────┼──────────────────────────────────────────────────────────────────────────────
102 │ Active      │ Deployed    │ 80    │ /example        │ mvn_org.apache.karaf.examples_karaf-war-example-webapp_4.3.0-SNAPSHOT_war (0)
```

We specify the context path on the URL. You can then point your browser to [http://localhost:8181/example].

### Feature

You can use the `webbundle` protocol on URL directly in a features repository.

It's illustrated in the `karaf-war-example-features` features repository.

Then, you simply have to add this features repository and directly install the `karaf-war-example` feature containing the war. This feature automatically installs the `war` feature, all in a row.

First, you add the features repository:

```
karaf@root()> feature:repo-add mvn:org.apache.karaf.examples/karaf-war-example-features/4.3.0-SNAPSHOT/xml
Adding feature url mvn:org.apache.karaf.examples/karaf-war-example-features/4.3.0-SNAPSHOT/xml
```

Then, you can install the `karaf-war-example`:

```
karaf@root()> feature:install karaf-war-example
```

You can see the war deployed using `web:list` command:

```
karaf@root()> web:list
ID  │ State       │ Web-State   │ Level │ Web-ContextPath │ Name
────┼─────────────┼─────────────┼───────┼─────────────────┼─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
102 │ Active      │ Deployed    │ 80    │ /example        │ file__home_jbonofre_.m2_repository_org_apache_karaf_examples_karaf-war-example-webapp_4.3.0-SNAPSHOT_karaf-war-example-webapp-4.3.0-SNAPSHOT.war (0)
```

You can then point your browser to [http://localhost:8181/example].