Initial attempt at deploying to gradle plugin portal (#2440)

.travis.yml

@@ -133,6 +133,8 @@ after_success:
         cd modules/openapi-generator-gradle-plugin;
         ./gradlew -Psigning.keyId="$SIGNING_KEY" -Psigning.password="$SIGNING_PASSPHRASE" -Psigning.secretKeyRingFile="${TRAVIS_BUILD_DIR}/sec.gpg" -PossrhUsername="${SONATYPE_USERNAME}" -PossrhPassword="${SONATYPE_PASSWORD}" uploadArchives --no-daemon;
         echo "Finished ./gradlew uploadArchives";
+        ./gradlew publishPlugins
+        echo "Finished ./gradlew publishPlugins (plugin portal)"
         popd;
       elif ([[ "$TRAVIS_BRANCH" =~ ^[0-9]+\.[0-9]+\.x$ ]]) ; then
         mvn clean deploy --settings CI/settings.xml;
@@ -141,6 +143,8 @@ after_success:
         cd modules/openapi-generator-gradle-plugin;
         ./gradlew -PossrhUsername="${SONATYPE_USERNAME}" -PossrhPassword="${SONATYPE_PASSWORD}" uploadArchives --no-daemon;
         echo "Finished ./gradlew uploadArchives";
+        ./gradlew publishPlugins
+        echo "Finished ./gradlew publishPlugins (plugin portal)"
         popd;
       fi;
     fi;

modules/openapi-generator-gradle-plugin/build.gradle

@@ -11,10 +11,14 @@ buildscript {
         maven {
             url "https://oss.sonatype.org/content/repositories/snapshots/"
         }
+        maven {
+            url "https://plugins.gradle.org/m2/"
+        }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath "gradle.plugin.org.gradle.kotlin:gradle-kotlin-dsl-plugins:1.0-rc-3"
+        classpath "com.gradle.publish:plugin-publish-plugin:0.10.1"
     }
 }
 
@@ -29,6 +33,7 @@ specifications as part of your build. Other tasks are available as command line
 """
 ext.isReleaseVersion = !version.endsWith("SNAPSHOT")
 
+apply plugin: 'com.gradle.plugin-publish'
 apply plugin: 'java-gradle-plugin'
 apply plugin: 'maven'
 apply plugin: 'signing'
@@ -39,6 +44,7 @@ sourceCompatibility = 1.8
 targetCompatibility = 1.8
 
 repositories {
+    jcenter()
     mavenCentral()
     mavenLocal()
     maven {
@@ -90,6 +96,23 @@ gradlePlugin {
     }
 }
 
+pluginBundle {
+    // These settings are set for the whole plugin bundle
+    website = 'https://openapi-generator.tech/'
+    vcsUrl = 'https://github.com/OpenAPITools/openapi-generator'
+    description = 'OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec (v2, v3)'
+
+    plugins {
+        // first plugin
+        openApiGenerator {
+            id = 'org.openapi.generator'
+            displayName = 'OpenAPI Generator Gradle Plugin'
+            tags = ['openapi-3.0', 'openapi-2.0', 'openapi', 'swagger', 'codegen', 'sdk']
+            version = "$openApiGeneratorVersion"
+        }
+    }
+}
+
 // signing will require three keys to be defined: signing.keyId, signing.password, and signing.secretKeyRingFile.
 // These can be passed to the gradle command:
 //     ./gradlew -Psigning.keyId=yourid