Add buildpack option for image building

This commit adds configuration to the Maven and Gradle plugins to
allow a list of buildpacks to be provided to the image building
goal and task.

Fixes gh-21722

Author: scottfrederick

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/build.gradle

@@ -13,6 +13,7 @@ dependencies {
 	api("org.apache.commons:commons-compress:1.19")
 	api("org.apache.httpcomponents:httpclient")
 	api("org.springframework:spring-core")
+	api("org.tomlj:tomlj:1.0.0")
 
 	testImplementation(project(":spring-boot-project:spring-boot-tools:spring-boot-test-support"))
 	testImplementation("com.jayway.jsonpath:json-path")

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/build/BuildRequest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2021 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.
@@ -17,8 +17,10 @@
 package org.springframework.boot.buildpack.platform.build;
 
 import java.io.File;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.LinkedHashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.function.Function;
 
@@ -61,6 +63,8 @@ public class BuildRequest {
 
 	private final boolean publish;
 
+	private final List<BuildpackReference> buildpacks;
+
 	BuildRequest(ImageReference name, Function<Owner, TarArchive> applicationContent) {
 		Assert.notNull(name, "Name must not be null");
 		Assert.notNull(applicationContent, "ApplicationContent must not be null");
@@ -74,11 +78,12 @@ public class BuildRequest {
 		this.pullPolicy = PullPolicy.ALWAYS;
 		this.publish = false;
 		this.creator = Creator.withVersion("");
+		this.buildpacks = Collections.emptyList();
 	}
 
 	BuildRequest(ImageReference name, Function<Owner, TarArchive> applicationContent, ImageReference builder,
 			ImageReference runImage, Creator creator, Map<String, String> env, boolean cleanCache,
-			boolean verboseLogging, PullPolicy pullPolicy, boolean publish) {
+			boolean verboseLogging, PullPolicy pullPolicy, boolean publish, List<BuildpackReference> buildpacks) {
 		this.name = name;
 		this.applicationContent = applicationContent;
 		this.builder = builder;
@@ -89,6 +94,7 @@ public class BuildRequest {
 		this.verboseLogging = verboseLogging;
 		this.pullPolicy = pullPolicy;
 		this.publish = publish;
+		this.buildpacks = buildpacks;
 	}
 
 	/**
@@ -99,7 +105,8 @@ public class BuildRequest {
 	public BuildRequest withBuilder(ImageReference builder) {
 		Assert.notNull(builder, "Builder must not be null");
 		return new BuildRequest(this.name, this.applicationContent, builder.inTaggedOrDigestForm(), this.runImage,
-				this.creator, this.env, this.cleanCache, this.verboseLogging, this.pullPolicy, this.publish);
+				this.creator, this.env, this.cleanCache, this.verboseLogging, this.pullPolicy, this.publish,
+				this.buildpacks);
 	}
 
 	/**
@@ -109,7 +116,8 @@ public BuildRequest withBuilder(ImageReference builder) {
 	 */
 	public BuildRequest withRunImage(ImageReference runImageName) {
 		return new BuildRequest(this.name, this.applicationContent, this.builder, runImageName.inTaggedOrDigestForm(),
-				this.creator, this.env, this.cleanCache, this.verboseLogging, this.pullPolicy, this.publish);
+				this.creator, this.env, this.cleanCache, this.verboseLogging, this.pullPolicy, this.publish,
+				this.buildpacks);
 	}
 
 	/**
@@ -120,7 +128,7 @@ public BuildRequest withRunImage(ImageReference runImageName) {
 	public BuildRequest withCreator(Creator creator) {
 		Assert.notNull(creator, "Creator must not be null");
 		return new BuildRequest(this.name, this.applicationContent, this.builder, this.runImage, creator, this.env,
-				this.cleanCache, this.verboseLogging, this.pullPolicy, this.publish);
+				this.cleanCache, this.verboseLogging, this.pullPolicy, this.publish, this.buildpacks);
 	}
 
 	/**
@@ -135,7 +143,8 @@ public BuildRequest withEnv(String name, String value) {
 		Map<String, String> env = new LinkedHashMap<>(this.env);
 		env.put(name, value);
 		return new BuildRequest(this.name, this.applicationContent, this.builder, this.runImage, this.creator,
-				Collections.unmodifiableMap(env), this.cleanCache, this.verboseLogging, this.pullPolicy, this.publish);
+				Collections.unmodifiableMap(env), this.cleanCache, this.verboseLogging, this.pullPolicy, this.publish,
+				this.buildpacks);
 	}
 
 	/**
@@ -149,7 +158,7 @@ public BuildRequest withEnv(Map<String, String> env) {
 		updatedEnv.putAll(env);
 		return new BuildRequest(this.name, this.applicationContent, this.builder, this.runImage, this.creator,
 				Collections.unmodifiableMap(updatedEnv), this.cleanCache, this.verboseLogging, this.pullPolicy,
-				this.publish);
+				this.publish, this.buildpacks);
 	}
 
 	/**
@@ -159,7 +168,7 @@ public BuildRequest withEnv(Map<String, String> env) {
 	 */
 	public BuildRequest withCleanCache(boolean cleanCache) {
 		return new BuildRequest(this.name, this.applicationContent, this.builder, this.runImage, this.creator, this.env,
-				cleanCache, this.verboseLogging, this.pullPolicy, this.publish);
+				cleanCache, this.verboseLogging, this.pullPolicy, this.publish, this.buildpacks);
 	}
 
 	/**
@@ -169,7 +178,7 @@ public BuildRequest withCleanCache(boolean cleanCache) {
 	 */
 	public BuildRequest withVerboseLogging(boolean verboseLogging) {
 		return new BuildRequest(this.name, this.applicationContent, this.builder, this.runImage, this.creator, this.env,
-				this.cleanCache, verboseLogging, this.pullPolicy, this.publish);
+				this.cleanCache, verboseLogging, this.pullPolicy, this.publish, this.buildpacks);
 	}
 
 	/**
@@ -179,7 +188,7 @@ public BuildRequest withVerboseLogging(boolean verboseLogging) {
 	 */
 	public BuildRequest withPullPolicy(PullPolicy pullPolicy) {
 		return new BuildRequest(this.name, this.applicationContent, this.builder, this.runImage, this.creator, this.env,
-				this.cleanCache, this.verboseLogging, pullPolicy, this.publish);
+				this.cleanCache, this.verboseLogging, pullPolicy, this.publish, this.buildpacks);
 	}
 
 	/**
@@ -189,7 +198,28 @@ public BuildRequest withPullPolicy(PullPolicy pullPolicy) {
 	 */
 	public BuildRequest withPublish(boolean publish) {
 		return new BuildRequest(this.name, this.applicationContent, this.builder, this.runImage, this.creator, this.env,
-				this.cleanCache, this.verboseLogging, this.pullPolicy, publish);
+				this.cleanCache, this.verboseLogging, this.pullPolicy, publish, this.buildpacks);
+	}
+
+	/**
+	 * Return a new {@link BuildRequest} with an updated buildpacks setting.
+	 * @param buildpacks a collection of buildpacks to use when building the image
+	 * @return an updated build request
+	 */
+	public BuildRequest withBuildpacks(BuildpackReference... buildpacks) {
+		Assert.notEmpty(buildpacks, "Buildpacks must not be empty");
+		return withBuildpacks(Arrays.asList(buildpacks));
+	}
+
+	/**
+	 * Return a new {@link BuildRequest} with an updated buildpacks setting.
+	 * @param buildpacks a collection of buildpacks to use when building the image
+	 * @return an updated build request
+	 */
+	public BuildRequest withBuildpacks(List<BuildpackReference> buildpacks) {
+		Assert.notNull(buildpacks, "Buildpacks must not be null");
+		return new BuildRequest(this.name, this.applicationContent, this.builder, this.runImage, this.creator, this.env,
+				this.cleanCache, this.verboseLogging, this.pullPolicy, this.publish, buildpacks);
 	}
 
 	/**
@@ -275,6 +305,14 @@ public PullPolicy getPullPolicy() {
 		return this.pullPolicy;
 	}
 
+	/**
+	 * Return the collection of buildpacks to use when building the image, if provided.
+	 * @return the collection of buildpacks
+	 */
+	public List<BuildpackReference> getBuildpacks() {
+		return this.buildpacks;
+	}
+
 	/**
 	 * Factory method to create a new {@link BuildRequest} from a JAR file.
 	 * @param jarFile the source jar file

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/build/Builder.java

@@ -17,6 +17,7 @@
 package org.springframework.boot.buildpack.platform.build;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.function.Consumer;
 
 import org.springframework.boot.buildpack.platform.build.BuilderMetadata.Stack;
@@ -29,6 +30,8 @@
 import org.springframework.boot.buildpack.platform.docker.transport.DockerEngineException;
 import org.springframework.boot.buildpack.platform.docker.type.Image;
 import org.springframework.boot.buildpack.platform.docker.type.ImageReference;
+import org.springframework.boot.buildpack.platform.io.IOBiConsumer;
+import org.springframework.boot.buildpack.platform.io.TarArchive;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
@@ -92,34 +95,35 @@ public Builder(BuildLog log, DockerConfiguration dockerConfiguration) {
 	public void build(BuildRequest request) throws DockerEngineException, IOException {
 		Assert.notNull(request, "Request must not be null");
 		this.log.start(request);
-		Image builderImage = getImage(request, ImageType.BUILDER);
+		String domain = request.getBuilder().getDomain();
+		PullPolicy pullPolicy = request.getPullPolicy();
+		ImageFetcher imageFetcher = new ImageFetcher(domain, getBuilderAuthHeader(), pullPolicy);
+		Image builderImage = imageFetcher.fetchImage(ImageType.BUILDER, request.getBuilder());
 		BuilderMetadata builderMetadata = BuilderMetadata.fromImage(builderImage);
+		request = withRunImageIfNeeded(request, builderMetadata.getStack());
+		Image runImage = imageFetcher.fetchImage(ImageType.RUNNER, request.getRunImage());
+		assertStackIdsMatch(runImage, builderImage);
 		BuildOwner buildOwner = BuildOwner.fromEnv(builderImage.getConfig().getEnv());
-		request = determineRunImage(request, builderImage, builderMetadata.getStack());
-		EphemeralBuilder builder = new EphemeralBuilder(buildOwner, builderImage, builderMetadata, request.getCreator(),
-				request.getEnv());
-		this.docker.image().load(builder.getArchive(), UpdateListener.none());
+		Buildpacks buildpacks = getBuildpacks(request, imageFetcher, builderMetadata);
+		EphemeralBuilder ephemeralBuilder = new EphemeralBuilder(buildOwner, builderImage, builderMetadata,
+				request.getCreator(), request.getEnv(), buildpacks);
+		this.docker.image().load(ephemeralBuilder.getArchive(), UpdateListener.none());
 		try {
-			executeLifecycle(request, builder);
+			executeLifecycle(request, ephemeralBuilder);
 			if (request.isPublish()) {
 				pushImage(request.getName());
 			}
 		}
 		finally {
-			this.docker.image().remove(builder.getName(), true);
+			this.docker.image().remove(ephemeralBuilder.getName(), true);
 		}
 	}
 
-	private BuildRequest determineRunImage(BuildRequest request, Image builderImage, Stack builderStack)
-			throws IOException {
-		if (request.getRunImage() == null) {
-			ImageReference runImage = getRunImageReferenceForStack(builderStack);
-			request = request.withRunImage(runImage);
+	private BuildRequest withRunImageIfNeeded(BuildRequest request, Stack builderStack) {
+		if (request.getRunImage() != null) {
+			return request;
 		}
-		assertImageRegistriesMatch(request);
-		Image runImage = getImage(request, ImageType.RUNNER);
-		assertStackIdsMatch(runImage, builderImage);
-		return request;
+		return request.withRunImage(getRunImageReferenceForStack(builderStack));
 	}
 
 	private ImageReference getRunImageReferenceForStack(Stack stack) {
@@ -128,32 +132,22 @@ private ImageReference getRunImageReferenceForStack(Stack stack) {
 		return ImageReference.of(name).inTaggedOrDigestForm();
 	}
 
-	private Image getImage(BuildRequest request, ImageType imageType) throws IOException {
-		ImageReference imageReference = (imageType == ImageType.BUILDER) ? request.getBuilder() : request.getRunImage();
-
-		if (request.getPullPolicy() == PullPolicy.ALWAYS) {
-			return pullImage(imageReference, imageType);
-		}
+	private void assertStackIdsMatch(Image runImage, Image builderImage) {
+		StackId runImageStackId = StackId.fromImage(runImage);
+		StackId builderImageStackId = StackId.fromImage(builderImage);
+		Assert.state(runImageStackId.equals(builderImageStackId), () -> "Run image stack '" + runImageStackId
+				+ "' does not match builder stack '" + builderImageStackId + "'");
+	}
 
-		try {
-			return this.docker.image().inspect(imageReference);
-		}
-		catch (DockerEngineException exception) {
-			if (request.getPullPolicy() == PullPolicy.IF_NOT_PRESENT && exception.getStatusCode() == 404) {
-				return pullImage(imageReference, imageType);
-			}
-			else {
-				throw exception;
-			}
-		}
+	private Buildpacks getBuildpacks(BuildRequest request, ImageFetcher imageFetcher, BuilderMetadata builderMetadata) {
+		BuildpackResolverContext resolverContext = new BuilderResolverContext(imageFetcher, builderMetadata);
+		return BuildpackResolvers.resolveAll(resolverContext, request.getBuildpacks());
 	}
 
-	private Image pullImage(ImageReference reference, ImageType imageType) throws IOException {
-		Consumer<TotalProgressEvent> progressConsumer = this.log.pullingImage(reference, imageType);
-		TotalProgressPullListener listener = new TotalProgressPullListener(progressConsumer);
-		Image image = this.docker.image().pull(reference, listener, getBuilderAuthHeader());
-		this.log.pulledImage(image, imageType);
-		return image;
+	private void executeLifecycle(BuildRequest request, EphemeralBuilder builder) throws IOException {
+		try (Lifecycle lifecycle = new Lifecycle(this.log, this.docker, request, builder)) {
+			lifecycle.execute();
+		}
 	}
 
 	private void pushImage(ImageReference reference) throws IOException {
@@ -173,25 +167,83 @@ private String getPublishAuthHeader() {
 				? this.dockerConfiguration.getPublishRegistryAuthentication().getAuthHeader() : null;
 	}
 
-	private void assertImageRegistriesMatch(BuildRequest request) {
-		if (getBuilderAuthHeader() != null) {
-			Assert.state(request.getRunImage().getDomain().equals(request.getBuilder().getDomain()),
-					"Builder image '" + request.getBuilder() + "' and run image '" + request.getRunImage()
-							+ "' must be pulled from the same authenticated registry");
+	/**
+	 * Internal utility class used to fetch images.
+	 */
+	private class ImageFetcher {
+
+		private final String domain;
+
+		private final String authHeader;
+
+		private final PullPolicy pullPolicy;
+
+		ImageFetcher(String domain, String authHeader, PullPolicy pullPolicy) {
+			this.domain = domain;
+			this.authHeader = authHeader;
+			this.pullPolicy = pullPolicy;
+		}
+
+		Image fetchImage(ImageType type, ImageReference reference) throws IOException {
+			Assert.notNull(type, "Type must not be null");
+			Assert.notNull(reference, "Reference must not be null");
+			Assert.state(this.authHeader == null || reference.getDomain().equals(this.domain),
+					() -> String.format("%s '%s' must be pulled from the '%s' authenticated registry",
+							StringUtils.capitalize(type.getDescription()), reference, this.domain));
+			if (this.pullPolicy == PullPolicy.ALWAYS) {
+				return pullImage(reference, type);
+			}
+			try {
+				return Builder.this.docker.image().inspect(reference);
+			}
+			catch (DockerEngineException ex) {
+				if (this.pullPolicy == PullPolicy.IF_NOT_PRESENT && ex.getStatusCode() == 404) {
+					return pullImage(reference, type);
+				}
+				throw ex;
+			}
+		}
+
+		private Image pullImage(ImageReference reference, ImageType imageType) throws IOException {
+			TotalProgressPullListener listener = new TotalProgressPullListener(
+					Builder.this.log.pullingImage(reference, imageType));
+			Image image = Builder.this.docker.image().pull(reference, listener, this.authHeader);
+			Builder.this.log.pulledImage(image, imageType);
+			return image;
 		}
-	}
 
-	private void assertStackIdsMatch(Image runImage, Image builderImage) {
-		StackId runImageStackId = StackId.fromImage(runImage);
-		StackId builderImageStackId = StackId.fromImage(builderImage);
-		Assert.state(runImageStackId.equals(builderImageStackId), () -> "Run image stack '" + runImageStackId
-				+ "' does not match builder stack '" + builderImageStackId + "'");
 	}
 
-	private void executeLifecycle(BuildRequest request, EphemeralBuilder builder) throws IOException {
-		try (Lifecycle lifecycle = new Lifecycle(this.log, this.docker, request, builder)) {
-			lifecycle.execute();
+	/**
+	 * {@link BuildpackResolverContext} implementation for the {@link Builder}.
+	 */
+	private class BuilderResolverContext implements BuildpackResolverContext {
+
+		private final ImageFetcher imageFetcher;
+
+		private final BuilderMetadata builderMetadata;
+
+		BuilderResolverContext(ImageFetcher imageFetcher, BuilderMetadata builderMetadata) {
+			this.imageFetcher = imageFetcher;
+			this.builderMetadata = builderMetadata;
 		}
+
+		@Override
+		public List<BuildpackMetadata> getBuildpackMetadata() {
+			return this.builderMetadata.getBuildpacks();
+		}
+
+		@Override
+		public Image fetchImage(ImageReference reference, ImageType imageType) throws IOException {
+			return this.imageFetcher.fetchImage(imageType, reference);
+		}
+
+		@Override
+		public void exportImageLayers(ImageReference reference, IOBiConsumer<String, TarArchive> exports)
+				throws IOException {
+			Builder.this.docker.image().exportLayers(reference, exports);
+		}
+
 	}
 
 }