Pull maven -src jars when available alongside jars re:

https://github.com/bazelbuild/bazel/issues/308

RELNOTES: None.
PiperOrigin-RevId: 166219871

3 files changed, 169 insertions, 52 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/bazel/repository/JarDecompressor.java b/src/main/java/com/google/devtools/build/lib/bazel/repository/JarDecompressor.java
index 703c4a32dd..26286adef0 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/repository/JarDecompressor.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/repository/JarDecompressor.java
@@ -15,6 +15,7 @@
 package com.google.devtools.build.lib.bazel.repository;
 
 import com.google.common.base.Joiner;
+import com.google.common.base.Optional;
 import com.google.devtools.build.lib.bazel.repository.DecompressorValue.Decompressor;
 import com.google.devtools.build.lib.rules.repository.RepositoryFunction;
 import com.google.devtools.build.lib.rules.repository.RepositoryFunction.RepositoryFunctionException;
@@ -34,34 +35,46 @@ public class JarDecompressor implements Decompressor {
   protected JarDecompressor() {
   }
 
-  /**
-   * The .jar can be used compressed, so this just exposes it in a way Bazel can use.
-   *
-   * <p>It moves the jar from some-name/x/y/z/foo.jar to some-name/jar/foo.jar and creates a
-   * BUILD.bazel file containing one entry: the .jar.
-   */
   @Override
   @Nullable
   public Path decompress(DecompressorDescriptor descriptor) throws RepositoryFunctionException {
-    // Example: archiveFile is external/some-name/foo.jar.
-    String baseName = descriptor.archivePath().getBaseName();
+    return decompressWithSrcjar(descriptor, Optional.absent());
+  }
 
+  /**
+   * The jar (and srcjar if available) can be used compressed, so this just exposes them in a way
+   * Bazel can use.
+   *
+   * <p>It moves the jar(s) from some-name/x/y/z/foo.jar to some-name/jar/foo.jar and creates a
+   * BUILD.bazel file containing only the jar(s).
+   */
+  public Path decompressWithSrcjar(
+      DecompressorDescriptor descriptor, Optional<DecompressorDescriptor> srcjarDescriptor)
+      throws RepositoryFunctionException {
     try {
+      // external/some-name/
       FileSystemUtils.createDirectoryAndParents(descriptor.repositoryPath());
-      // external/some-name/WORKSPACE.
+      // external/some-name/WORKSPACE
       RepositoryFunction.createWorkspaceFile(
           descriptor.repositoryPath(), descriptor.targetKind(), descriptor.targetName());
-      // external/some-name/jar.
+      // external/some-name/jar/
       Path jarDirectory = descriptor.repositoryPath().getRelative(getPackageName());
       FileSystemUtils.createDirectoryAndParents(jarDirectory);
-      // external/some-name/repository/jar/foo.jar is a symbolic link to the jar in
-      // external/some-name.
-      Path jarSymlink = jarDirectory.getRelative(baseName);
-      if (!jarSymlink.exists()) {
-        jarSymlink.createSymbolicLink(descriptor.archivePath());
-      }
-      // external/some-name/repository/jar/BUILD.bazel defines the //jar target.
+      // external/some-name/jar/BUILD.bazel defines the //jar target.
       Path buildFile = jarDirectory.getRelative("BUILD.bazel");
+
+      // Example: get foo.jar from external/some-name/foo.jar.
+      String baseName = descriptor.archivePath().getBaseName();
+      makeSymlink(descriptor);
+      String buildFileContents;
+      if (srcjarDescriptor.isPresent()) {
+        String srcjarBaseName = srcjarDescriptor.get().archivePath().getBaseName();
+        makeSymlink(srcjarDescriptor.get());
+        buildFileContents = createBuildFileWithSrcjar(baseName, srcjarBaseName);
+      } else {
+        buildFileContents = createBuildFile(baseName);
+      }
+
       FileSystemUtils.writeLinesAs(
           buildFile,
           Charset.forName("UTF-8"),
@@ -69,7 +82,7 @@ public class JarDecompressor implements Decompressor {
               + descriptor.targetKind()
               + " rule "
               + descriptor.targetName(),
-          createBuildFile(baseName));
+          buildFileContents);
       if (descriptor.executable()) {
         descriptor.archivePath().chmod(0755);
       }
@@ -80,6 +93,25 @@ public class JarDecompressor implements Decompressor {
     return descriptor.repositoryPath();
   }
 
+  /*
+   * Links some-name/x/y/z/foo.jar to some-name/jar/foo.jar (represented by {@code descriptor}
+   */
+  protected void makeSymlink(DecompressorDescriptor descriptor) throws RepositoryFunctionException {
+    try {
+      Path jarDirectory = descriptor.repositoryPath().getRelative(getPackageName());
+      // external/some-name/jar/foo.jar is a symbolic link to the jar in
+      // external/some-name.
+      Path jarSymlink = jarDirectory.getRelative(descriptor.archivePath().getBaseName());
+      if (!jarSymlink.exists()) {
+        jarSymlink.createSymbolicLink(descriptor.archivePath());
+      }
+    } catch (IOException e) {
+      throw new RepositoryFunctionException(
+          new IOException("Error auto-creating jar repo structure: " + e.getMessage()),
+          Transience.TRANSIENT);
+    }
+  }
+
   protected String getPackageName() {
     return "jar";
   }
@@ -99,4 +131,24 @@ public class JarDecompressor implements Decompressor {
             "    visibility = ['//visibility:public']",
             ")");
   }
+
+  protected String createBuildFileWithSrcjar(String baseName, String srcjarBaseName) {
+    return Joiner.on("\n")
+        .join(
+            "java_import(",
+            "    name = 'jar',",
+            "    jars = ['" + baseName + "'],",
+            "    srcjar = '" + srcjarBaseName + "',",
+            "    visibility = ['//visibility:public']",
+            ")",
+            "",
+            "filegroup(",
+            "    name = 'file',",
+            "    srcs = [",
+            "        '" + baseName + "',",
+            "        '" + srcjarBaseName + "',",
+            "    ],",
+            "    visibility = ['//visibility:public']",
+            ")");
+  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/repository/MavenDownloader.java b/src/main/java/com/google/devtools/build/lib/bazel/repository/MavenDownloader.java
index 264173ef8f..e663a80499 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/repository/MavenDownloader.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/repository/MavenDownloader.java
@@ -14,6 +14,7 @@
 
 package com.google.devtools.build.lib.bazel.repository;
 
+import com.google.common.base.Optional;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
@@ -72,9 +73,10 @@ public class MavenDownloader extends HttpDownloader {
   }
 
   /**
-   * Download the Maven artifact to the output directory. Returns the path to the jar.
+   * Download the Maven artifact to the output directory. Returns the path to the jar (and the
+   * srcjar if available).
    */
-  public Path download(String name, WorkspaceAttributeMapper mapper, Path outputDirectory,
+  public JarPaths download(String name, WorkspaceAttributeMapper mapper, Path outputDirectory,
       MavenServerValue serverValue) throws IOException, EvalException {
     this.name = name;
     this.outputDirectory = outputDirectory;
@@ -82,59 +84,73 @@ public class MavenDownloader extends HttpDownloader {
     String url = serverValue.getUrl();
     Server server = serverValue.getServer();
 
+    // Initialize maven artifacts
     Artifact artifact;
-    String artifactId = mapper.get("artifact", Type.STRING);
-    String sha1 = mapper.isAttributeValueExplicitlySpecified("sha1")
-        ? mapper.get("sha1", Type.STRING) : null;
-        if (sha1 != null && !KeyType.SHA1.isValid(sha1)) {
-          throw new IOException("Invalid SHA-1 for maven_jar " + name + ": '" + sha1 + "'");
-        }
+    String artifactCoords = mapper.get("artifact", Type.STRING);
+    String sha1 =
+        mapper.isAttributeValueExplicitlySpecified("sha1") ? mapper.get("sha1", Type.STRING) : null;
+    if (sha1 != null && !KeyType.SHA1.isValid(sha1)) {
+      throw new IOException("Invalid SHA-1 for maven_jar " + name + ": '" + sha1 + "'");
+    }
+
     try {
-      artifact = new DefaultArtifact(artifactId);
+      artifact = new DefaultArtifact(artifactCoords);
     } catch (IllegalArgumentException e) {
       throw new IOException(e.getMessage());
     }
- 
+
     boolean isCaching = repositoryCache.isEnabled() && KeyType.SHA1.isValid(sha1);
 
     if (isCaching) {
       Path downloadPath = getDownloadDestination(artifact);
       Path cachedDestination = repositoryCache.get(sha1, downloadPath, KeyType.SHA1);
       if (cachedDestination != null) {
-        return cachedDestination;
+        return new JarPaths(cachedDestination, Optional.absent());
       }
     }
 
+    // Setup env for fetching jars
     MavenConnector connector = new MavenConnector(outputDirectory.getPathString());
     RepositorySystem system = connector.newRepositorySystem();
     RepositorySystemSession session = connector.newRepositorySystemSession(system);
+    RemoteRepository repository =
+        new RemoteRepository.Builder(name, MavenServerValue.DEFAULT_ID, url)
+            .setAuthentication(new MavenAuthentication(server))
+            .build();
 
-    RemoteRepository repository = new RemoteRepository.Builder(
-        name, MavenServerValue.DEFAULT_ID, url)
-        .setAuthentication(new MavenAuthentication(server))
-        .build();
-    ArtifactRequest artifactRequest = new ArtifactRequest();
-
-    artifactRequest.setArtifact(artifact);
-    artifactRequest.setRepositories(ImmutableList.of(repository));
-
+    // Try fetching jar.
+    final Path jarDownload;
     try {
-      ArtifactResult artifactResult = system.resolveArtifact(session, artifactRequest);
-      artifact = artifactResult.getArtifact();
+      artifact = downloadArtifact(artifact, repository, session, system);
     } catch (ArtifactResolutionException e) {
       throw new IOException("Failed to fetch Maven dependency: " + e.getMessage());
     }
 
-    Path downloadPath = outputDirectory.getRelative(artifact.getFile().getAbsolutePath());
+    // Try also fetching srcjar.
+    Artifact artifactWithSrcs = srcjarCoords(artifact);
+    try {
+      artifactWithSrcs = downloadArtifact(artifactWithSrcs, repository, session, system);
+    } catch (ArtifactResolutionException e) {
+      // Intentionally ignored - missing srcjar is not an error.
+    }
+
+    jarDownload = outputDirectory.getRelative(artifact.getFile().getAbsolutePath());
     // Verify checksum.
     if (!Strings.isNullOrEmpty(sha1)) {
-      RepositoryCache.assertFileChecksum(sha1, downloadPath, KeyType.SHA1);
+      RepositoryCache.assertFileChecksum(sha1, jarDownload, KeyType.SHA1);
     }
 
     if (isCaching) {
-      repositoryCache.put(sha1, downloadPath, KeyType.SHA1);
+      repositoryCache.put(sha1, jarDownload, KeyType.SHA1);
+    }
+
+    if (artifactWithSrcs.getFile() != null) {
+      Path srcjarDownload =
+          outputDirectory.getRelative(artifactWithSrcs.getFile().getAbsolutePath());
+      return new JarPaths(jarDownload, Optional.fromNullable(srcjarDownload));
+    } else {
+      return new JarPaths(jarDownload, Optional.absent());
     }
-    return downloadPath;
   }
 
   private Path getDownloadDestination(Artifact artifact) {
@@ -149,6 +165,40 @@ public class MavenDownloader extends HttpDownloader {
     return outputDirectory.getRelative(joiner.toString());
   }
 
+  private Artifact srcjarCoords(Artifact jar) {
+    return new DefaultArtifact(
+        jar.getGroupId(), jar.getArtifactId(), "sources", jar.getExtension(), jar.getVersion());
+  }
+
+  /*
+   * Set up request for and resolve (retrieve to local repo) artifact
+   */
+  private Artifact downloadArtifact(
+      Artifact artifact,
+      RemoteRepository repository,
+      RepositorySystemSession session,
+      RepositorySystem system)
+      throws ArtifactResolutionException {
+    ArtifactRequest artifactRequest = new ArtifactRequest();
+    artifactRequest.setArtifact(artifact);
+    artifactRequest.setRepositories(ImmutableList.of(repository));
+    ArtifactResult artifactResult = system.resolveArtifact(session, artifactRequest);
+    return artifactResult.getArtifact();
+  }
+
+  /*
+   * Class for packaging srcjar and jar paths together when srcjar is available.
+   */
+  static class JarPaths {
+    final Path jar;
+    @Nullable final Optional<Path> srcjar;
+
+    private JarPaths(Path jar, Optional<Path> srcjar) {
+      this.jar = jar;
+      this.srcjar = srcjar;
+    }
+  }
+
   private static class MavenAuthentication implements Authentication {
 
     private final Map<String, String> authenticationInfo;
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/repository/MavenJarFunction.java b/src/main/java/com/google/devtools/build/lib/bazel/repository/MavenJarFunction.java
index 907227e959..45aa2bab6f 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/repository/MavenJarFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/repository/MavenJarFunction.java
@@ -14,9 +14,11 @@
 
 package com.google.devtools.build.lib.bazel.repository;
 
+import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
 import com.google.devtools.build.lib.analysis.BlazeDirectories;
 import com.google.devtools.build.lib.analysis.RuleDefinition;
+import com.google.devtools.build.lib.bazel.repository.MavenDownloader.JarPaths;
 import com.google.devtools.build.lib.bazel.rules.workspace.MavenJarRule;
 import com.google.devtools.build.lib.packages.Rule;
 import com.google.devtools.build.lib.rules.repository.RepositoryDirectoryValue;
@@ -98,7 +100,7 @@ public class MavenJarFunction extends HttpArchiveFunction {
     if (env.valuesMissing()) {
       return null;
     }
-    
+
     Path outputDir = getExternalRepositoryDirectory(directories).getRelative(rule.getName());
     return createOutputTree(rule, outputDir, serverValue);
   }
@@ -110,10 +112,11 @@ public class MavenJarFunction extends HttpArchiveFunction {
 
     createDirectory(outputDirectory);
     String name = rule.getName();
-    Path repositoryJar;
+    final JarPaths repositoryJars;
     try {
-      repositoryJar = mavenDownloader.download(
-          name, WorkspaceAttributeMapper.of(rule), outputDirectory, serverValue);
+      repositoryJars =
+          mavenDownloader.download(
+              name, WorkspaceAttributeMapper.of(rule), outputDirectory, serverValue);
     } catch (IOException e) {
       throw new RepositoryFunctionException(e, Transience.TRANSIENT);
     } catch (EvalException e) {
@@ -121,13 +124,25 @@ public class MavenJarFunction extends HttpArchiveFunction {
     }
 
     // Add a WORKSPACE file & BUILD file to the Maven jar.
-    Path result = DecompressorValue.decompress(DecompressorDescriptor.builder()
+    DecompressorDescriptor jar = getDescriptorBuilder(name, repositoryJars.jar, outputDirectory);
+    DecompressorDescriptor srcjar =
+        repositoryJars.srcjar.isPresent()
+            ? getDescriptorBuilder(name, repositoryJars.srcjar.get(), outputDirectory)
+            : null;
+    JarDecompressor decompressor = (JarDecompressor) jar.getDecompressor();
+    Path result = decompressor.decompressWithSrcjar(jar, Optional.fromNullable(srcjar));
+    return RepositoryDirectoryValue.builder().setPath(result);
+  }
+
+  private DecompressorDescriptor getDescriptorBuilder(String name, Path jar, Path outputDirectory)
+      throws RepositoryFunctionException, InterruptedException {
+    return DecompressorDescriptor.builder()
         .setDecompressor(JarDecompressor.INSTANCE)
         .setTargetKind(MavenJarRule.NAME)
         .setTargetName(name)
-        .setArchivePath(repositoryJar)
-        .setRepositoryPath(outputDirectory).build());
-    return RepositoryDirectoryValue.builder().setPath(result);
+        .setArchivePath(jar)
+        .setRepositoryPath(outputDirectory)
+        .build();
   }
 
   /**