Rework Gradle build

This commit introduces a _convention plugin_ for RIFE2 support.
It provides a number of advantages:

- the build logic is clearly separated from the build script,
which now only contains user-specific configuration, like the
framework version or how to configure test logging
- it fixes a number of issues like hardcoded dependencies
(`dependsOn` is in general a mistake)
- it removes the need to resolve the agent path eagerly
- it makes the agent configurable
- it clearly separates the user classpath from the RIFE
classpath (both for precompiling templates and for the agent)
- template compilation is cached
- it avoids the abuse of `src/main/resources` to put
templates and uses a dedicated directory instead, which
removes the need for exclusions

In addition, this should make it relatively straightforward
to convert the convention plugin into a proper RIFE2 plugin,
by extracting the code in `build-logic` into its own
repository then publishing to the Gradle plugin portal.

app/build.gradle.kts

@@ -2,7 +2,8 @@ import org.gradle.api.tasks.testing.logging.TestExceptionFormat
 import org.gradle.api.tasks.testing.logging.TestLogEvent
 
 plugins {
-    java
+    application
+    id("com.uwyn.rife2")
 }
 
 base {
@@ -10,25 +11,22 @@ base {
     version = 1.0
 }
 
+application {
+    mainClass.set("hello.App")
+}
+
 repositories {
     // Use Maven Central for resolving dependencies.
     mavenCentral()
     maven { url = uri("https://s01.oss.sonatype.org/content/repositories/snapshots") } // only needed for SNAPSHOT
 }
 
-sourceSets {
-    main {
-        runtimeClasspath = files(file("src/main/resources"), runtimeClasspath);
-    }
-}
-
-sourceSets.main {
-    resources.exclude("templates/**")
+rife2 {
+    version.set("1.3.0")
+    useAgent.set(true)
 }
 
 dependencies {
-    implementation("com.uwyn.rife2:rife2:1.3.0")
-    runtimeOnly("com.uwyn.rife2:rife2:1.3.0:agent")
     runtimeOnly("org.eclipse.jetty:jetty-server:11.0.13")
     runtimeOnly("org.eclipse.jetty:jetty-servlet:11.0.13")
     runtimeOnly("org.slf4j:slf4j-simple:2.0.5")
@@ -38,68 +36,11 @@ dependencies {
 }
 
 tasks {
-    val dependencies = configurations
-        .runtimeClasspath.get().files;
-    val rifeAgentJar = dependencies
-        .filter { it.toString().contains("rife2") }
-        .filter { it.toString().endsWith("-agent.jar") }[0]
-
     test {
-        jvmArgs = listOf("-javaagent:$rifeAgentJar")
         useJUnitPlatform()
         testLogging {
             exceptionFormat = TestExceptionFormat.FULL
             events = setOf(TestLogEvent.PASSED, TestLogEvent.SKIPPED, TestLogEvent.FAILED)
         }
     }
-
-    // Pre-compile the RIFE2 templates to bytecode for deployment
-    register<JavaExec>("precompileHtmlTemplates") {
-        classpath = sourceSets["main"].runtimeClasspath
-        mainClass.set("rife.template.TemplateDeployer")
-        args = listOf(
-            "-verbose",
-            "-t", "html",
-            "-d", "${projectDir}/build/classes/java/main",
-            "-encoding", "UTF-8", "${projectDir}/src/main/resources/templates"
-        )
-    }
-
-    register("precompileTemplates") {
-        dependsOn("precompileHtmlTemplates")
-    }
-
-    // Ensure that the templates are pre-compiled before building the jar
-    jar {
-        dependsOn("precompileTemplates")
-    }
-
-    // Replace the run task with one that uses the RIFE2 agent
-    register<JavaExec>("run") {
-        classpath = sourceSets["main"].runtimeClasspath
-        mainClass.set("hello.App")
-        jvmArgs = listOf("-javaagent:$rifeAgentJar")
-    }
-
-    // These two tasks create a self-container UberJar
-    register<Copy>("copyWebapp") {
-        from("src/main/")
-        include("webapp/**")
-        into("$buildDir/webapp")
-    }
-
-    register<Jar>("uberJar") {
-        dependsOn("jar")
-        dependsOn("copyWebapp")
-        archiveBaseName.set("hello-uber")
-        duplicatesStrategy = DuplicatesStrategy.EXCLUDE
-        manifest {
-            attributes["Main-Class"] = "hello.AppUber"
-        }
-        val uberDependencies = dependencies
-            .filter { !it.toString().matches("rife2-.*agent\\.jar".toRegex()) }
-            .map(::zipTree)
-        from(uberDependencies, "$buildDir/webapp")
-        with(jar.get())
-    }
-}
+}