Add Bazel support, fixes #88

.bazelignore

@@ -0,0 +1,2 @@
+examples/
+

.bazelversion

@@ -0,0 +1 @@
+5.1.1

.github/workflows/ci.yml

@@ -21,6 +21,20 @@ jobs:
         with:
           go-version: "^1.13.1"
       - run: sbt test
+  bazel:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - run: yarn global add @bazel/bazelisk
+      - run: bazel build //... --//semanticdb-javac:enabled=true
+      - run: bazel run lsif-semanticdb:bazel -- --sourceroot "$PWD"
+      - run: du -h dump.lsif-typed
+      - run: bazel build //... --@lsif_java//semanticdb-javac:enabled=true
+        working-directory: examples/bazel-example
+      - run: bazel run @lsif_java//lsif-semanticdb:bazel -- --sourceroot "$PWD"
+        working-directory: examples/bazel-example
+      - run: du -h dump.lsif-typed
+        working-directory: examples/bazel-example
   check:
     runs-on: ubuntu-latest
     steps:

.gitignore

@@ -56,3 +56,7 @@ dump.lsif
 
 ./generated
 /sources
+bazel-bin
+bazel-lsif-java
+bazel-out
+bazel-testlogs

.tool-versions

@@ -0,0 +1 @@
+golang 1.17.5

WORKSPACE

@@ -0,0 +1,59 @@
+workspace(name = "lsif_java_tests")
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+##############
+# Bazel stdlib
+##############
+# To update this version, copy-paste instructions from https://github.com/bazelbuild/bazel-skylib/releases
+http_archive(
+    name = "bazel_skylib",
+    sha256 = "1c531376ac7e5a180e0237938a2536de0c54d93f5c278634818e0efc952dd56c",
+    urls = [
+        "https://github.com/bazelbuild/bazel-skylib/releases/download/1.0.3/bazel-skylib-1.0.3.tar.gz",
+        "https://mirror.bazel.build/github.com/bazelbuild/bazel-skylib/releases/download/1.0.3/bazel-skylib-1.0.3.tar.gz",
+    ],
+)
+
+##########
+# Protobuf
+##########
+# To update this version, copy-paste instructions from https://github.com/bazelbuild/rules_proto/releases
+http_archive(
+    name = "rules_proto",
+    sha256 = "e017528fd1c91c5a33f15493e3a398181a9e821a804eb7ff5acdd1d2d6c2b18d",
+    strip_prefix = "rules_proto-4.0.0-3.20.0",
+    urls = [
+        "https://github.com/bazelbuild/rules_proto/archive/refs/tags/4.0.0-3.20.0.tar.gz",
+    ],
+)
+load("@rules_proto//proto:repositories.bzl", "rules_proto_dependencies", "rules_proto_toolchains")
+rules_proto_dependencies()
+rules_proto_toolchains()
+
+##############
+# JVM External
+##############
+# To update this version, copy-paste instructions from https://github.com/bazelbuild/rules_jvm_external/releases
+RULES_JVM_EXTERNAL_TAG = "4.2"
+RULES_JVM_EXTERNAL_SHA = "cd1a77b7b02e8e008439ca76fd34f5b07aecb8c752961f9640dea15e9e5ba1ca"
+http_archive(
+    name = "rules_jvm_external",
+    strip_prefix = "rules_jvm_external-%s" % RULES_JVM_EXTERNAL_TAG,
+    sha256 = RULES_JVM_EXTERNAL_SHA,
+    url = "https://github.com/bazelbuild/rules_jvm_external/archive/%s.zip" % RULES_JVM_EXTERNAL_TAG,
+)
+load("@rules_jvm_external//:repositories.bzl", "rules_jvm_external_deps")
+rules_jvm_external_deps()
+load("@rules_jvm_external//:setup.bzl", "rules_jvm_external_setup")
+rules_jvm_external_setup()
+load("@rules_jvm_external//:defs.bzl", "maven_install")
+maven_install(
+    artifacts = [
+        "com.google.protobuf:protobuf-java:3.15.6",
+        "com.google.protobuf:protobuf-java-util:3.15.6",
+        "org.projectlombok:lombok:1.18.22",
+    ],
+    repositories = [
+         "https://repo1.maven.org/maven2",
+    ],
+)

examples/bazel-example/WORKSPACE

@@ -0,0 +1,70 @@
+
+# This is an end-to-end example of how to consume lsif-java from an external repository.
+workspace(name = "lsif_java_example")
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+##############
+# Bazel stdlib
+##############
+# To update this version, copy-paste instructions from https://github.com/bazelbuild/bazel-skylib/releases
+http_archive(
+    name = "bazel_skylib",
+    sha256 = "1c531376ac7e5a180e0237938a2536de0c54d93f5c278634818e0efc952dd56c",
+    urls = [
+        "https://github.com/bazelbuild/bazel-skylib/releases/download/1.0.3/bazel-skylib-1.0.3.tar.gz",
+        "https://mirror.bazel.build/github.com/bazelbuild/bazel-skylib/releases/download/1.0.3/bazel-skylib-1.0.3.tar.gz",
+    ],
+)
+
+##############
+# lsif-java
+##############
+local_repository(
+    name = "lsif_java",
+    path = "../.."
+)
+# TODO: add commented out `http_archive` example once this workspace file is available on GitHub.
+
+##########
+# Protobuf
+##########
+# To update this version, copy-paste instructions from https://github.com/bazelbuild/rules_proto/releases
+http_archive(
+    name = "rules_proto",
+    sha256 = "e017528fd1c91c5a33f15493e3a398181a9e821a804eb7ff5acdd1d2d6c2b18d",
+    strip_prefix = "rules_proto-4.0.0-3.20.0",
+    urls = [
+        "https://github.com/bazelbuild/rules_proto/archive/refs/tags/4.0.0-3.20.0.tar.gz",
+    ],
+)
+load("@rules_proto//proto:repositories.bzl", "rules_proto_dependencies", "rules_proto_toolchains")
+rules_proto_dependencies()
+rules_proto_toolchains()
+
+##############
+# JVM External
+##############
+# To update this version, copy-paste instructions from https://github.com/bazelbuild/rules_jvm_external/releases
+RULES_JVM_EXTERNAL_TAG = "4.2"
+RULES_JVM_EXTERNAL_SHA = "cd1a77b7b02e8e008439ca76fd34f5b07aecb8c752961f9640dea15e9e5ba1ca"
+http_archive(
+    name = "rules_jvm_external",
+    strip_prefix = "rules_jvm_external-%s" % RULES_JVM_EXTERNAL_TAG,
+    sha256 = RULES_JVM_EXTERNAL_SHA,
+    url = "https://github.com/bazelbuild/rules_jvm_external/archive/%s.zip" % RULES_JVM_EXTERNAL_TAG,
+)
+load("@rules_jvm_external//:repositories.bzl", "rules_jvm_external_deps")
+rules_jvm_external_deps()
+load("@rules_jvm_external//:setup.bzl", "rules_jvm_external_setup")
+rules_jvm_external_setup()
+load("@rules_jvm_external//:defs.bzl", "maven_install")
+maven_install(
+    artifacts = [
+        "com.google.protobuf:protobuf-java:3.15.6", # Required dependency by lsif-java.
+        "com.google.protobuf:protobuf-java-util:3.15.6", # Required dependency by lsif-java.
+        "com.google.guava:guava:31.0-jre", # Not required dependency, only used by tests.
+    ],
+    repositories = [
+         "https://repo1.maven.org/maven2",
+    ],
+)

examples/bazel-example/src/main/java/example/BUILD

@@ -0,0 +1,19 @@
+# We import the custom `java_library` implementation that automatically adds the
+# SemanticDB compiler plugin based on the presence of the flag
+# `--@lsif_java//semanticdb-javac:enabled=true`. By default, this java_library
+# rule works just like the official java_library rule. Feel free to copy-paste
+# the `semanticdb:defs.bzl` file and adapt to your needs. This example is only
+# for demonstration purposes.
+load("@lsif_java//semanticdb-javac:defs.bzl", "java_library")
+
+package(
+    default_visibility = ["//visibility:public"],
+)
+
+java_library(
+	name = "example",
+	srcs = ["Example.java"],
+	deps = [
+		"@maven//:com_google_guava_guava",
+	],
+)

examples/bazel-example/src/main/java/example/Example.java

@@ -0,0 +1,9 @@
+package example;
+import com.google.common.util.concurrent.Futures;
+
+public class Example {
+	public static void hello() {
+		System.out.println(Futures.immediateCancelledFuture());
+	}
+
+}

lsif-java/src/main/scala/com/sourcegraph/lsif_java/commands/IndexSemanticdbCommand.scala

@@ -33,6 +33,9 @@ final case class IndexSemanticdbCommand(
     @Description(
       "Whether to process the SemanticDB files in parallel"
     ) parallel: Boolean = true,
+    @Description(
+      "Whether to infer the location of SemanticDB files based as produced by Bazel"
+    ) bazel: Boolean = true,
     @Description("URL to a PackageHub instance")
     @Hidden
     packagehub: Option[String] = None,

lsif-semanticdb/BUILD

@@ -0,0 +1,36 @@
+load("@rules_java//java:defs.bzl", "java_binary", "java_library", "java_proto_library")
+load("@rules_proto//proto:defs.bzl", "proto_library")
+
+package(
+    default_visibility = ["//visibility:public"],
+)
+
+java_binary(
+    name = "bazel",
+    main_class = "com.sourcegraph.lsif_semanticdb.BazelBuildTool",
+    runtime_deps = [
+        ":lsif-semanticdb",
+    ],
+)
+
+java_library(
+    name = "lsif-semanticdb",
+    srcs = glob(["src/main/java/**/*.java"]),
+    deps = [
+        ":all_java_proto",
+        "//semanticdb-java",
+        "//semanticdb-java/src/main/protobuf:semanticdb_java_proto",
+        "@maven//:com_google_protobuf_protobuf_java",
+        "@maven//:com_google_protobuf_protobuf_java_util",
+    ],
+)
+
+java_proto_library(
+    name = "all_java_proto",
+    deps = [":all_proto"],
+)
+
+proto_library(
+    name = "all_proto",
+    srcs = glob(["src/main/protobuf/*.proto"]),
+)

lsif-semanticdb/src/main/java/com/sourcegraph/lsif_semanticdb/BazelBuildTool.java

@@ -0,0 +1,130 @@
+package com.sourcegraph.lsif_semanticdb;
+
+import com.sourcegraph.lsif_java.Bazelbuild;
+import com.sourcegraph.lsif_protocol.LsifToolInfo;
+
+import java.io.*;
+import java.nio.file.FileSystems;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.PathMatcher;
+import java.sql.Array;
+import java.util.*;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+public class BazelBuildTool {
+
+  public static int runAndReturnExitCode(String[] args) throws IOException {
+    Optional<BazelOptions> maybeOptions = BazelOptions.parse(args);
+    if (!maybeOptions.isPresent()) {
+      return 1;
+    }
+    BazelOptions options = maybeOptions.get();
+    if (options.isHelp) {
+      BazelOptions.printHelp();
+      return 0;
+    }
+    if (options.isVersion) {
+      System.out.println(
+          "This command-line tool has no version because it is supposed to be compiled from source.");
+      return 0;
+    }
+
+    List<MavenPackage> mavenPackages = mavenPackages(options);
+    LsifSemanticdbOptions lsifOptions =
+        new LsifSemanticdbOptions(
+            options.targetroots,
+            options.output,
+            options.sourceroot,
+            new LsifSemanticdbReporter() {
+              @Override
+              public void error(Throwable e) {
+                e.printStackTrace(System.err);
+              }
+            },
+            LsifToolInfo.newBuilder().setName("lsif-java").setVersion("HEAD").build(),
+            "java",
+            LsifOutputFormat.TYPED_PROTOBUF,
+            options.parallel,
+            mavenPackages,
+            "");
+    LsifSemanticdb.run(lsifOptions);
+    if (!lsifOptions.reporter.hasErrors()) {
+      System.out.println("done: " + lsifOptions.output);
+    }
+    return 0;
+  }
+
+  public static List<MavenPackage> mavenPackages(BazelOptions options) throws IOException {
+    ArrayList<MavenPackage> result = new ArrayList<>();
+    if (!options.isQueryMavenImports) {
+      return result;
+    }
+    Bazelbuild.QueryResult jvmImports = runBazelQuery(options, "kind('.*_import', @maven//...)");
+    Path baseDirectory =
+        options.sourceroot.resolve("bazel-bin").resolve("external").resolve("maven");
+    PathMatcher jarPattern = FileSystems.getDefault().getPathMatcher("glob:**.jar");
+    for (Bazelbuild.Target target : jvmImports.getTargetList()) {
+      if (target.getType() != Bazelbuild.Target.Discriminator.RULE) {
+        continue;
+      }
+      Bazelbuild.Rule rule = target.getRule();
+      MavenPackage basePackage = null;
+      List<Path> jarDirectories = new ArrayList<>();
+      for (Bazelbuild.Attribute attribute : rule.getAttributeList()) {
+        if (attribute.getName().equals("jars")) {
+          for (String tag : attribute.getStringListValueList()) {
+            if (tag.startsWith("@maven//:")) {
+              jarDirectories.add(
+                  baseDirectory.resolve(tag.substring("@maven//:".length())).getParent());
+            }
+          }
+        }
+        if (attribute.getName().equals("tags")) {
+          for (String tag : attribute.getStringListValueList()) {
+            if (tag.startsWith("maven_coordinates=")) {
+              String[] parts = tag.substring("maven_coordinates=".length()).split(":");
+              if (parts.length == 3) {
+                // The jar part is populated via `withJar()` below.
+                basePackage = new MavenPackage(/* jar = */ null, parts[0], parts[1], parts[2]);
+              }
+            }
+          }
+        }
+      }
+      if (basePackage == null) {
+        continue;
+      }
+      for (Path directory : jarDirectories) {
+        try (Stream<Path> list = Files.list(directory)) {
+          List<Path> jars = list.filter(jarPattern::matches).collect(Collectors.toList());
+          for (Path jar : jars) {
+            result.add(basePackage.withJar(jar));
+          }
+        }
+      }
+    }
+    return result;
+  }
+
+  public static Bazelbuild.QueryResult runBazelQuery(BazelOptions options, String query)
+      throws IOException {
+    List<String> command = Arrays.asList(options.bazelBinary, "query", query, "--output=proto");
+    System.out.println("running: " + String.join(" ", command));
+    Process bazelQuery = new ProcessBuilder(command).directory(options.sourceroot.toFile()).start();
+    byte[] bytes = InputStreamBytes.readAll(bazelQuery.getInputStream());
+    if (bazelQuery.isAlive()) {
+      throw new RuntimeException(new String(InputStreamBytes.readAll(bazelQuery.getErrorStream())));
+    }
+    int exitValue = bazelQuery.exitValue();
+    if (exitValue != 0) {
+      throw new RuntimeException("bazel command failed\n" + new String(bytes));
+    }
+    return Bazelbuild.QueryResult.parseFrom(bytes);
+  }
+
+  public static void main(String[] args) throws IOException {
+    System.exit(runAndReturnExitCode(args));
+  }
+}