Remove Ant build and set up Gradle build

Remove Ant build files and libraries (`build` directory), the add-ons
will be built with Gradle.
Remove Eclipse files (`.classpath` and `.project`), they are generated
when the project is imported to Eclipse.
Remove all main libraries (`lib` directory) except fuzz add-on, they
will be obtained from Maven repository (Maven Central by default).
Rename the fuzz add-on to have `jar` extension (to be properly consumed
by IDEs).
Add Gradle wrapper and main build files.
Add top level project, `addOns`, to contain and configure the add-ons.
Each add-on will be relocated to be under `addOns` and have the
following directory layout:
 - `src/main/java/` for main Java source files;
 - `src/main/resources/` for main resource files;
 - `src/main/javahelp/` for JavaHelp files;
 - `src/main/zapHomeFiles/` for home files;
 - `src/test/java/` for test Java source files;
 - `src/test/resources/` for test resource files.

Update Travis CI configuration file for Gradle build.
Update `.gitignore` for Gradle and common IDE files.
Update `README.md` with instructions on how to build the add-ons.
Move example add-on manifest (`ZapAddOn.xml`) to top level directory
`docs`.

.gitignore

@@ -1,12 +1,33 @@
-# Intellij
-.idea/
-*.iml
-*.iws
-*.eml
-out/
-/bin/
-build/build/
-build/buildtest/
-build/results/
-build/temp/
-build/zap-exts/
+# Gradle
+#-------
+.gradle
+/build
+/buildSrc/build
+/addOns/**/build
+
+# IDEA
+# ----
+.idea
+.shelf
+/*.iml
+/*.ipr
+/*.iws
+/buildSrc/*.iml
+/buildSrc/*.ipr
+/buildSrc/*.iws
+/buildSrc/out
+/out
+
+# Eclipse
+# -------
+*.classpath
+*.project
+*.settings
+/bin
+/buildSrc/bin
+/addOns/**/bin
+
+# NetBeans
+# --------
+.nb-gradle
+.nb-gradle-properties

.travis.yml

@@ -1,6 +1,15 @@
 language: java
-script: ant -buildfile build/build.xml test
 
 jdk:
   - oraclejdk8
   - openjdk11
+
+before_cache:
+  - rm -f  $HOME/.gradle/caches/modules-2/modules-2.lock
+  - rm -fr $HOME/.gradle/caches/*/plugin-resolution/
+
+cache:
+  directories:
+    - $HOME/.gradle/caches/
+    - $HOME/.gradle/wrapper/
+    - $HOME/.m2/repository/webdriver/

README.md

@@ -7,3 +7,21 @@ If you are using the latest version of ZAP then you can browse and download add-
 You can also import add-ons you have downloaded manually from https://github.com/zaproxy/zap-extensions/releases via the "File / Load Add-on File..." menu option.
 
 Please see the [wiki](https://github.com/zaproxy/zap-extensions/wiki) for more details.
+
+## Building
+
+The add-ons are built with [Gradle], each add-on has its own project which is located under the `addOns` project/directory.
+
+To build all add-ons, simply run:
+
+    ./gradlew build
+
+in the main directory of the project, the add-ons will be placed in the directory `build/zapAddOn/bin/` of each project.
+
+To build an add-on individually run:
+
+    ./gradlew :addOns:<name>:build
+
+replacing `<name>` with the name of the add-on (e.g. `reveal`).
+
+[Gradle]: https://gradle.org/

addOns/addOns.gradle.kts

@@ -0,0 +1,101 @@
+import org.zaproxy.gradle.addon.AddOnPlugin
+import org.zaproxy.gradle.addon.AddOnPluginExtension
+import org.zaproxy.gradle.addon.manifest.ManifestExtension
+import org.zaproxy.gradle.addon.manifest.tasks.ConvertChangelogToChanges
+import org.zaproxy.gradle.addon.wiki.WikiGenExtension
+import org.zaproxy.gradle.addon.zapversions.ZapVersionsExtension
+
+plugins {
+    id("org.zaproxy.add-on") version "0.1.0" apply false
+}
+
+description = "Common configuration of the add-ons."
+
+val zapCoreHelpWikiDir = "$rootDir/../zap-core-help-wiki/"
+val zapExtensionsWikiDir = "$rootDir/../zap-extensions-wiki/"
+
+val parentProjects = listOf(
+)
+
+val mainAddOns = listOf(
+)
+val weeklyAddOns = mainAddOns + listOf(
+)
+
+mapOf("main" to mainAddOns, "weekly" to weeklyAddOns).forEach { entry ->
+    tasks {
+        val name = entry.key
+        val nameCapitalized = name.capitalize()
+        register("copy${nameCapitalized}AddOns") {
+            group = "ZAP"
+            description = "Copies the $name release add-ons to zaproxy project."
+            subprojects(entry.value) {
+                dependsOn(it.tasks.named(AddOnPlugin.COPY_ADD_ON_TASK_NAME))
+            }
+        }
+
+        register("list${nameCapitalized}AddOns") {
+            group = "ZAP"
+            description = "Lists the $name release add-ons."
+            doLast {
+                subprojects(entry.value) { println(it.name) }
+            }
+        }
+    }
+}
+
+subprojects {
+    if (parentProjects.contains(project.name)) {
+        return@subprojects
+    }
+
+    apply(plugin = "java-library")
+    apply(plugin = "org.zaproxy.add-on")
+
+    java {
+        sourceCompatibility = JavaVersion.VERSION_1_8
+        targetCompatibility = JavaVersion.VERSION_1_8
+    }
+
+    val generateManifestChanges by tasks.registering(ConvertChangelogToChanges::class) {
+        changelog.set(file("CHANGELOG.md"))
+        manifestChanges.set(file("$buildDir/zapAddOn/manifest-changes.html"))
+    }
+
+    zapAddOn {
+        manifest {
+            changesFile.set(generateManifestChanges.flatMap { it.manifestChanges })
+        }
+
+        wikiGen {
+            wikiFilesPrefix.set("HelpAddons${zapAddOn.addOnId.get().capitalize()}")
+            wikiDir.set(project.provider { project.layout.projectDirectory.dir(if (mainAddOns.contains(zapAddOn.addOnId.get())) zapCoreHelpWikiDir else zapExtensionsWikiDir) })
+        }
+
+        zapVersions {
+            downloadUrl.set("https://github.com/zaproxy/zap-extensions/releases/download/2.7")
+        }
+    }
+}
+
+fun subprojects(addOns: List<String>, action: (Project) -> Unit) {
+    subprojects.filter { !parentProjects.contains(it.name) && addOns.contains(it.zapAddOn.addOnId.get()) }.forEach(action)
+}
+
+fun Project.java(configure: JavaPluginExtension.() -> Unit): Unit =
+    (this as ExtensionAware).extensions.configure("java", configure)
+
+fun Project.zapAddOn(configure: AddOnPluginExtension.() -> Unit): Unit =
+    (this as ExtensionAware).extensions.configure("zapAddOn", configure)
+
+val Project.zapAddOn: AddOnPluginExtension get() =
+    (this as ExtensionAware).extensions.getByName("zapAddOn") as AddOnPluginExtension
+
+fun AddOnPluginExtension.manifest(configure: ManifestExtension.() -> Unit): Unit =
+    (this as ExtensionAware).extensions.configure("manifest", configure)
+
+fun AddOnPluginExtension.wikiGen(configure: WikiGenExtension.() -> Unit): Unit =
+    (this as ExtensionAware).extensions.configure("wikiGen", configure)
+
+fun AddOnPluginExtension.zapVersions(configure: ZapVersionsExtension.() -> Unit): Unit =
+    (this as ExtensionAware).extensions.configure("zapVersions", configure)

build.gradle.kts

@@ -0,0 +1,22 @@
+plugins {
+    id("com.diffplug.gradle.spotless") version "3.20.0"
+}
+
+allprojects {
+    apply(plugin = "com.diffplug.gradle.spotless")
+
+    repositories {
+        mavenCentral()
+    }
+
+    spotless {
+        kotlinGradle {
+            ktlint()
+        }
+    }
+
+    tasks.withType<JavaCompile>().configureEach {
+        options.encoding = "utf-8"
+        options.compilerArgs = listOf("-Xlint:all", "-Xlint:-path", "-Xlint:-options", "-Werror")
+    }
+}