Auto-updatable version ranges

This commit improves the version format so that the minor and patch
elements can hold a special 'x' character besides the version, i.e.
`1.x.x.RELEASE` or `2.4.x.BUILD-SNAPSHOT`. A `VersionParser` now takes
care to resolve those against a list of known Spring Boot versions.

This is particularly useful in version ranges that have to change when
the latest Spring Boot versions change. Spring Initializr already auto-
udpates itself based on the sagan metadata. When a range is using this
feature, it is also automatically updated.

It might be hard to track the actual range values on a given instance so
an `InfoContributor` is now automatically exposed to list them.

Closes gh-328

initializr-actuator/src/main/groovy/io/spring/initializr/actuate/autoconfigure/InitializrActuatorEndpointsAutoConfiguration.groovy

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2012-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.actuate.autoconfigure
+
+import io.spring.initializr.actuate.info.BomRangesInfoContributor
+import io.spring.initializr.metadata.InitializrMetadataProvider
+
+import org.springframework.context.annotation.Bean
+import org.springframework.context.annotation.Configuration
+
+/**
+ * {@link org.springframework.boot.autoconfigure.EnableAutoConfiguration
+ * Auto-configuration} to improve actuator endpoints with initializr specific information.
+ *
+ * @author Stephane Nicoll
+ */
+@Configuration
+class InitializrActuatorEndpointsAutoConfiguration {
+
+	@Bean
+	BomRangesInfoContributor bomRangesInfoContributor(
+			InitializrMetadataProvider metadataProvider) {
+		return new BomRangesInfoContributor(metadataProvider)
+	}
+
+}

initializr-actuator/src/main/groovy/io/spring/initializr/actuate/info/BomRangesInfoContributor.groovy

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2012-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.actuate.info
+
+import io.spring.initializr.metadata.InitializrMetadataProvider
+
+import org.springframework.boot.actuate.info.Info
+import org.springframework.boot.actuate.info.InfoContributor
+
+/**
+ * An {@link InfoContributor} that exposes the actual ranges used by each bom
+ * defined in the project.
+ *
+ * @author Stephane Nicoll
+ */
+class BomRangesInfoContributor implements InfoContributor {
+
+	private final InitializrMetadataProvider metadataProvider
+
+	BomRangesInfoContributor(InitializrMetadataProvider metadataProvider) {
+		this.metadataProvider = metadataProvider
+	}
+
+	@Override
+	void contribute(Info.Builder builder) {
+		def details = [:]
+		metadataProvider.get().configuration.env.boms.each { k, v ->
+			if (v.mappings) {
+				def bom = [:]
+				v.mappings.each {
+					String requirement = "Spring Boot ${it.determineVersionRangeRequirement()}"
+					bom[it.version] = requirement
+				}
+				details[k] = bom
+			}
+		}
+		if (details) {
+			builder.withDetail('bom-ranges', details)
+		}
+	}
+
+}

initializr-actuator/src/main/resources/META-INF/spring.factories

@@ -1,3 +1,4 @@
 org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
+io.spring.initializr.actuate.autoconfigure.InitializrActuatorEndpointsAutoConfiguration,\
 io.spring.initializr.actuate.autoconfigure.InitializrStatsAutoConfiguration,\
 io.spring.initializr.actuate.autoconfigure.InitializrMetricsConfiguration

initializr-actuator/src/test/groovy/io/spring/initializr/actuate/info/BomRangesInfoContributorTests.groovy

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2012-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.actuate.info
+
+import io.spring.initializr.metadata.BillOfMaterials
+import io.spring.initializr.metadata.InitializrMetadata
+import io.spring.initializr.metadata.SimpleInitializrMetadataProvider
+import io.spring.initializr.test.metadata.InitializrMetadataTestBuilder
+import org.junit.Test
+
+import org.springframework.boot.actuate.info.Info
+
+import static org.assertj.core.api.Assertions.assertThat
+import static org.assertj.core.api.Assertions.entry
+
+/**
+ * Tests for {@link BomRangesInfoContributor}
+ *
+ * @author Stephane Nicoll
+ */
+class BomRangesInfoContributorTests {
+
+	@Test
+	void noBom() {
+		def metadata = InitializrMetadataTestBuilder.withDefaults().build()
+		def info = getInfo(metadata)
+		assertThat(info.details).doesNotContainKeys('bom-ranges')
+	}
+
+	@Test
+	void noMapping() {
+		def bom = new BillOfMaterials(groupId: 'com.example', artifactId: 'bom', version: '1.0.0')
+		def metadata = InitializrMetadataTestBuilder.withDefaults()
+				.addBom('foo', bom)
+				.build()
+		def info = getInfo(metadata)
+		assertThat(info.details).doesNotContainKeys('bom-ranges')
+	}
+
+	@Test
+	void withMappings() {
+		BillOfMaterials bom = new BillOfMaterials(groupId: 'com.example',
+				artifactId: 'bom', version: '1.0.0')
+		bom.mappings << new BillOfMaterials.Mapping(
+				versionRange: '[1.3.0.RELEASE,1.3.8.RELEASE]', version: '1.1.0')
+		bom.mappings << new BillOfMaterials.Mapping(
+				versionRange: '1.3.8.BUILD-SNAPSHOT', version: '1.1.1-SNAPSHOT')
+		def metadata = InitializrMetadataTestBuilder.withDefaults()
+				.addBom('foo', bom)
+				.build()
+		def info = getInfo(metadata)
+		assertThat(info.details).containsKeys('bom-ranges')
+		Map<String,Object> ranges = info.details['bom-ranges'] as Map<String, Object>
+		assertThat(ranges).containsOnlyKeys('foo')
+		Map<String,Object> foo = ranges['foo'] as Map<String, Object>
+		assertThat(foo).containsExactly(
+				entry('1.1.0', 'Spring Boot >=1.3.0.RELEASE and <=1.3.8.RELEASE'),
+				entry('1.1.1-SNAPSHOT', 'Spring Boot >=1.3.8.BUILD-SNAPSHOT'))
+	}
+
+	private static Info getInfo(InitializrMetadata metadata) {
+		Info.Builder builder = new Info.Builder()
+		new BomRangesInfoContributor(new SimpleInitializrMetadataProvider(metadata))
+				.contribute(builder)
+		builder.build()
+	}
+
+}