Adds support for promoting to maven central (#78)

* Adds support for promoting to maven central

pom.xml

@@ -23,6 +23,14 @@
         <url>https://github.com/spring-cloud/spring-cloud-bindings</url>
     </scm>
 
+    <developers>
+		<developer>
+			<id>scb-team</id>
+			<name>Spring Cloud Bindings Team</name>
+			<organizationUrl>https://github.com/spring-cloud/spring-cloud-bindings/graphs/contributors</organizationUrl>
+		</developer>
+    </developers>
+
     <properties>
         <java.version>1.8</java.version>
         <jsr305.version>3.0.2</jsr305.version>
@@ -33,6 +41,8 @@
         <maven-compiler-plugin.version>3.8.1</maven-compiler-plugin.version>
         <maven-source-plugin.version>3.2.1</maven-source-plugin.version>
         <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
+        <maven-gpg-plugin.version>3.0.1</maven-gpg-plugin.version>
+        <maven-javadoc-plugin.version>3.4.1</maven-javadoc-plugin.version>
 
         <maven.compiler.source>${java.version}</maven.compiler.source>
         <maven.compiler.target>${java.version}</maven.compiler.target>
@@ -124,6 +134,39 @@
                     </execution>
                 </executions>
             </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-javadoc-plugin</artifactId>
+                <version>${maven-javadoc-plugin.version}</version>
+                <executions>
+                    <execution>
+                        <id>attach-javadocs</id>
+                        <goals>
+                            <goal>jar</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-gpg-plugin</artifactId>
+                <version>${maven-gpg-plugin.version}</version>
+                <executions>
+                    <execution>
+                        <id>sign-artifacts</id>
+                        <phase>verify</phase>
+                        <goals>
+                            <goal>sign</goal>
+                        </goals>
+                        <configuration>
+                            <gpgArguments>
+                                <arg>--pinentry-mode</arg>
+                                <arg>loopback</arg>
+                            </gpgArguments>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>

scripts/Dockerfile

@@ -1,6 +1,8 @@
 ARG base_image=ubuntu:bionic
 FROM ${base_image}
 
+ADD https://repo.spring.io/libs-release/io/spring/concourse/releasescripts/concourse-release-scripts/0.3.2/concourse-release-scripts-0.3.2.jar /opt/concourse-release-scripts.jar
+
 RUN apt-get update && apt-get install --no-install-recommends -y \
-    git \
+    git gnupg \
  && rm -rf /var/lib/apt/lists/*

scripts/deploy.sh

@@ -4,6 +4,29 @@ set -euo pipefail
 
 [[ -d "${PWD}"/maven && ! -d "${HOME}"/.m2 ]] && ln -s "${PWD}"/maven "${HOME}"/.m2
 
+function clean_gpg {
+    FINGERPRINT=$(gpg --list-keys | head -4 | tail -1 | tr -d ' ')
+    gpg --batch --yes --delete-secret-keys "$FINGERPRINT"
+    gpg --batch --yes --delete-keys "$FINGERPRINT"
+}
+
+trap clean_gpg EXIT
+gpg --batch --import-options import-show --import <(echo "$MAVEN_GPG_PRIVATE_KEY")
+
+mkdir -p ~/.m2
+cat <<EOF > ~/.m2/settings.xml
+<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 https://maven.apache.org/xsd/settings-1.0.0.xsd">
+  <servers>
+    <server>
+      <id>gpg.passphrase</id>
+      <passphrase>${MAVEN_GPG_PASSPHRASE}</passphrase>
+    </server>
+  </servers>
+</settings>
+EOF
+
 REPOSITORY="${PWD}"/repository
 
 cd source

scripts/promote-to-maven-central.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+export BUILD_INFO_LOCATION=$(pwd)/repository/build-info.json
+
+java -jar /opt/concourse-release-scripts.jar publishToCentral 'RELEASE' "$BUILD_INFO_LOCATION" repository
+
+echo "Sync complete"