Deploy web applications using embedded Tomcat

Testing | Deploy web applications using embedded Tomcat

The POM file (pom.xml)
Unit test example
Web application resources (index.html, web.xml)

The POM file (pom.xml)

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>mtitek.tomcat.embed.samples</groupId>
    <artifactId>mtitek-tomcat-embed-samples</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

        <maven.compiler.source>19</maven.compiler.source> <!-- maven-compiler-plugin property -->
        <maven.compiler.target>19</maven.compiler.target> <!-- maven-compiler-plugin property -->
    </properties>

    <dependencies>
        <!-- tomcat -->
        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-core</artifactId>
            <version>11.0.0-M1</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-logging-juli</artifactId>
            <version>9.0.0.M6</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-jasper</artifactId>
            <version>11.0.0-M1</version>
            <scope>test</scope>
        </dependency>

        <!-- shrinkwrap -->
        <dependency>
            <groupId>org.jboss.shrinkwrap</groupId>
            <artifactId>shrinkwrap-api</artifactId>
            <version>2.0.0-beta-1</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.jboss.shrinkwrap</groupId>
            <artifactId>shrinkwrap-impl-base</artifactId>
            <version>2.0.0-beta-1</version>
            <scope>test</scope>
        </dependency>

        <!-- ... -->
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpcore</artifactId>
            <version>4.4.16</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.5.14</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.12.0</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>2.11.0</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13.2</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.10.1</version>

                <configuration>
                    <encoding>UTF-8</encoding>
                    <source>${maven.compiler.source}</source> <!-- optional if maven.compiler.source property is set -->
                    <target>${maven.compiler.target}</target> <!-- optional if maven.compiler.target property is set -->
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

Unit test example

src/test/java/mtitek/tomcat/embed/samples/MyTomcatTest.java:

package mtitek.tomcat.embed.samples;

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;

import org.apache.catalina.Host;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.startup.Tomcat;
import org.apache.commons.io.IOUtils;
import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.util.EntityUtils;
import org.jboss.shrinkwrap.api.ShrinkWrap;
import org.jboss.shrinkwrap.api.spec.WebArchive;
import org.jboss.shrinkwrap.impl.base.exporter.zip.ZipExporterImpl;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.TemporaryFolder;

public class MyTomcatTest {
    @Rule
    public TemporaryFolder temporaryFolder = new TemporaryFolder();

    @Test
    public void test() throws IOException, LifecycleException {
        final File newFolder = temporaryFolder.newFolder("MyTomcatTest");
        final String baseDir = newFolder.getAbsolutePath();

        // creating a Tomcat instance
        final Tomcat tomcat = new Tomcat();

        // configure tomcat
        {
            // random unassigned HTTP port
            tomcat.setPort(0);

            tomcat.setBaseDir(baseDir);
        }

        // start tomcat
        {
            tomcat.start();
        }

        // deploy web app
        deployWebApp(tomcat, baseDir);

        // stop/destroy tomcat
        {
            tomcat.stop();
            tomcat.destroy();
        }
    }

    private static void deployWebApp(final Tomcat tomcat, final String tomcatBaseDir) throws IOException {
        final String webAppName = "simple";
        final String archiveName = webAppName + ".war";

        // adding resources to WebArchive
        {
            final WebArchive webArchive = ShrinkWrap.create(WebArchive.class, archiveName);
            webArchive.addAsWebResource("index.html");
            webArchive.setWebXML("web.xml");

            deployWebApp(tomcat, tomcatBaseDir, webArchive, webAppName);
        }

        // test web app
        {
            testWebApp(tomcat, "http://localhost:" + tomcat.getConnector().getLocalPort() + '/' + webAppName);
        }
    }

    private static void deployWebApp(final Tomcat tomcat, final String tomcatBaseDir, final WebArchive webArchive,
            final String webAppName) throws IOException {
        final Host host = tomcat.getHost();

        final File rootBase = new File(tomcatBaseDir, host.getAppBase());
        Files.createDirectories(rootBase.toPath());

        final File docBase = new File(rootBase, webArchive.getName());
        final String docBaseAbsolutePath = docBase.getAbsolutePath();

        new ZipExporterImpl(webArchive).exportTo(docBase, true);

        final String contextPath = '/' + webAppName;
        tomcat.addWebapp(host, contextPath, docBaseAbsolutePath);
    }

    private static void testWebApp(final Tomcat tomcat, final String resource) throws IOException {
        final HttpGet request = new HttpGet(resource);

        try (final CloseableHttpClient client = HttpClientBuilder.create().build();
                final CloseableHttpResponse response = client.execute(request)) {
            final HttpEntity entity = response.getEntity();

            System.out.println(IOUtils.toString(entity.getContent(), "UTF-8"));

            // close the content stream.
            EntityUtils.consumeQuietly(entity);
        }
    }
}

Notes:

► Adding resources to a WebArchive: addAsWebResource

final WebArchive webArchive = ShrinkWrap.create(WebArchive.class, archiveName);
webArchive.addAsWebResource("index.html");
webArchive.setWebXML("web.xml");

► Adding resources to a WebArchive: importDirectory

final WebArchive webArchive = ShrinkWrap.create(WebArchive.class, archiveName);

webArchive.merge(ShrinkWrap.create(GenericArchive.class).as(ExplodedImporter.class).importDirectory(archivePath).as(GenericArchive.class), "/", Filters.includeAll());

Web application resources (index.html, web.xml)

src/test/resources/index.html:

<html>
<head>
<title>HTML Page</title>
</head>
<body>
<h1>Hello Tomcat!!!</h1>
</body>
</html>

src/test/resources/web.xml:

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
    metadata-complete="true">

    <welcome-file-list>
        <welcome-file>index.html</welcome-file>
    </welcome-file-list>
</web-app>