Create Bazel rules for generating reactive bindings

Resolves #164

Author: mjduijn

.bazelignore

@@ -0,0 +1 @@
+demos/bazel

.gitignore

@@ -9,4 +9,6 @@ dependency-reduced-pom.xml
 .settings/
 .checkstyle
 .classpath
-.project
+.project
+bazel-*
+.ijwb/

BUILD.bazel

@@ -0,0 +1,9 @@
+workspace(name = "com_salesforce_servicelibs_reactive_grpc")
+
+load("//bazel:repositories.bzl", "repositories")
+
+repositories()
+
+load("@io_grpc_grpc_java//:repositories.bzl", "grpc_java_repositories")
+
+grpc_java_repositories()

WORKSPACE

@@ -0,0 +1,145 @@
+load("@bazel_tools//tools/jdk:toolchain_utils.bzl", "find_java_runtime_toolchain", "find_java_toolchain")
+
+# Taken from bazelbuild/rules_go license: Apache 2
+# https://github.com/bazelbuild/rules_go/blob/528f6faf83f85c23da367d61f784893d1b3bd72b/proto/compiler.bzl#L94
+# replaced `prefix = paths.join(..` with `prefix = "/".join(..`
+def _proto_path(src, proto):
+    """proto_path returns the string used to import the proto. This is the proto
+    source path within its repository, adjusted by import_prefix and
+    strip_import_prefix.
+
+    Args:
+        src: the proto source File.
+        proto: the ProtoInfo provider.
+
+    Returns:
+        An import path string.
+    """
+    if not hasattr(proto, "proto_source_root"):
+        # Legacy path. Remove when Bazel minimum version >= 0.21.0.
+        path = src.path
+        root = src.root.path
+        ws = src.owner.workspace_root
+        if path.startswith(root):
+            path = path[len(root):]
+        if path.startswith("/"):
+            path = path[1:]
+        if path.startswith(ws):
+            path = path[len(ws):]
+        if path.startswith("/"):
+            path = path[1:]
+        return path
+
+    if proto.proto_source_root == ".":
+        # true if proto sources were generated
+        prefix = src.root.path + "/"
+    elif proto.proto_source_root.startswith(src.root.path):
+        # sometimes true when import paths are adjusted with import_prefix
+        prefix = proto.proto_source_root + "/"
+    else:
+        # usually true when paths are not adjusted
+        prefix = "/".join([src.root.path, proto.proto_source_root]) + "/"
+    if not src.path.startswith(prefix):
+        # sometimes true when importing multiple adjusted protos
+        return src.path
+    return src.path[len(prefix):]
+
+def _reactive_grpc_library_impl(ctx):
+    proto = ctx.attr.proto[ProtoInfo]
+    descriptor_set_in = proto.transitive_descriptor_sets
+
+    gensrcjar = ctx.actions.declare_file("%s-proto-gensrc.jar" % ctx.label.name)
+
+    args = ctx.actions.args()
+    args.add(ctx.executable.reactive_plugin.path, format = "--plugin=protoc-gen-reactive-grpc-plugin=%s")
+    args.add("--reactive-grpc-plugin_out=:{0}".format(gensrcjar.path))
+    args.add_joined("--descriptor_set_in", descriptor_set_in, join_with = ":")
+    for src in proto.check_deps_sources.to_list():
+        args.add(_proto_path(src, proto))
+
+    ctx.actions.run(
+        inputs = descriptor_set_in,
+        tools = [ctx.executable.reactive_plugin],
+        outputs = [gensrcjar],
+        executable = ctx.executable._protoc,
+        arguments = [args],
+    )
+
+    deps = [java_common.make_non_strict(dep[JavaInfo]) for dep in ctx.attr.deps]
+    deps += [dep[JavaInfo] for dep in ctx.attr.reactive_deps]
+
+    java_info = java_common.compile(
+        ctx,
+        deps = deps,
+        host_javabase = find_java_runtime_toolchain(ctx, ctx.attr._host_javabase),
+        java_toolchain = find_java_toolchain(ctx, ctx.attr._java_toolchain),
+        output = ctx.outputs.jar,
+        output_source_jar = ctx.outputs.srcjar,
+        source_jars = [gensrcjar],
+    )
+
+    return [java_info]
+
+_reactive_grpc_library = rule(
+    attrs = {
+        "proto": attr.label(
+            mandatory = True,
+            providers = [ProtoInfo],
+        ),
+        "deps": attr.label_list(
+            mandatory = True,
+            allow_empty = False,
+            providers = [JavaInfo],
+        ),
+        "_protoc": attr.label(
+            default = Label("@com_google_protobuf//:protoc"),
+            executable = True,
+            cfg = "host",
+        ),
+        "reactive_deps": attr.label_list(
+            mandatory = True,
+            allow_empty = False,
+            providers = [JavaInfo],
+        ),
+        "reactive_plugin": attr.label(
+            mandatory = True,
+            executable = True,
+            cfg = "host",
+        ),
+        "_java_toolchain": attr.label(
+            default = Label("@bazel_tools//tools/jdk:current_java_toolchain"),
+        ),
+        "_host_javabase": attr.label(
+            cfg = "host",
+            default = Label("@bazel_tools//tools/jdk:current_host_java_runtime"),
+        ),
+    },
+    fragments = ["java"],
+    outputs = {
+        "jar": "lib%{name}.jar",
+        "srcjar": "lib%{name}-src.jar",
+    },
+    provides = [JavaInfo],
+    implementation = _reactive_grpc_library_impl,
+)
+
+def reactor_grpc_library(**kwargs):
+    _reactive_grpc_library(
+        reactive_plugin = "@com_salesforce_servicelibs_reactive_grpc//reactor/reactor-grpc:reactor_grpc_bin",
+        reactive_deps = [
+            "@com_salesforce_servicelibs_reactive_grpc//reactor/reactor-grpc-stub",
+            "@io_projectreactor_reactor_core",
+        ],
+        **kwargs
+    )
+
+def rx_grpc_library(**kwargs):
+    _reactive_grpc_library(
+        reactive_plugin = "@com_salesforce_servicelibs_reactive_grpc//rx-java/rxgrpc:rxgrpc_bin",
+        reactive_deps = [
+            "@com_salesforce_servicelibs_reactive_grpc//rx-java/rxgrpc-stub",
+            "@com_salesforce_servicelibs_reactive_grpc//common/reactive-grpc-common",
+            "@io_reactivex_rxjava2_rxjava",
+        ],
+        **kwargs
+    )

bazel/BUILD.bazel

@@ -0,0 +1,69 @@
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+load("@bazel_tools//tools/build_defs/repo:java.bzl", "java_import_external")
+
+def repositories(
+        omit_org_reactivestreams_reactive_streams = False,
+        omit_io_projectreactor_reactor_core = False,
+        omit_io_reactivex_rxjava2_rxjava = False,
+        omit_io_grpc_grpc_java = False,
+        omit_com_salesforce_servicelibs_jprotoc = False,
+        omit_com_github_spullara_mustache_java_compiler = False):
+    if not omit_org_reactivestreams_reactive_streams:
+        java_import_external(
+            name = "org_reactivestreams_reactive_streams",
+            jar_urls = ["http://central.maven.org/maven2/org/reactivestreams/reactive-streams/1.0.2/reactive-streams-1.0.2.jar"],
+            jar_sha256 = "cc09ab0b140e0d0496c2165d4b32ce24f4d6446c0a26c5dc77b06bdf99ee8fae",
+            srcjar_urls = ["http://central.maven.org/maven2/org/reactivestreams/reactive-streams/1.0.2/reactive-streams-1.0.2-sources.jar"],
+            srcjar_sha256 = "963a6480f46a64013d0f144ba41c6c6e63c4d34b655761717a436492886f3667",
+            licenses = ["notice"],  # Apache 2.0
+        )
+
+    if not omit_io_projectreactor_reactor_core:
+        java_import_external(
+            name = "io_projectreactor_reactor_core",
+            jar_urls = ["http://central.maven.org/maven2/io/projectreactor/reactor-core/3.2.6.RELEASE/reactor-core-3.2.6.RELEASE.jar"],
+            jar_sha256 = "8962081aa9e0fbe1685cc2746471b232f93f58e269cc89b54efebcb99c65af1a",
+            srcjar_urls = ["http://central.maven.org/maven2/io/projectreactor/reactor-core/3.2.6.RELEASE/reactor-core-3.2.6.RELEASE-sources.jar"],
+            srcjar_sha256 = "b871669ed12aee2af22f20a611bf871c7f848caede85bc19b0ef08ef5f79bc46",
+            licenses = ["notice"],  # Apache 2.0
+        )
+
+    if not omit_io_reactivex_rxjava2_rxjava:
+        java_import_external(
+            name = "io_reactivex_rxjava2_rxjava",
+            jar_urls = ["http://central.maven.org/maven2/io/reactivex/rxjava2/rxjava/2.2.7/rxjava-2.2.7.jar"],
+            jar_sha256 = "23798f1b5fecac2aaaa3e224fd0e73f41dc081802c7bd2a6e91030bad36b9013",
+            srcjar_urls = ["http://central.maven.org/maven2/io/reactivex/rxjava2/rxjava/2.2.7/rxjava-2.2.7-sources.jar"],
+            srcjar_sha256 = "b7ee7e2b2ce07eda19755e511757427701f4081a051cace1efd69cf0bfcc8ff2",
+            licenses = ["notice"],  # Apache 2.0
+        )
+
+    if not omit_io_grpc_grpc_java:
+        io_grpc_grpc_java_version = "v1.21.0"
+
+        http_archive(
+            name = "io_grpc_grpc_java",
+            sha256 = "2137a2b568e8266d6c269c995c7ba68db3d8d7d7936087c540fdbfadae577f81",
+            strip_prefix = "grpc-java-%s" % io_grpc_grpc_java_version[1:],
+            urls = ["https://github.com/grpc/grpc-java/archive/%s.zip" % io_grpc_grpc_java_version],
+        )
+
+    if not omit_com_salesforce_servicelibs_jprotoc:
+        java_import_external(
+            name = "com_salesforce_servicelibs_jprotoc",
+            jar_urls = ["http://central.maven.org/maven2/com/salesforce/servicelibs/jprotoc/0.9.1/jprotoc-0.9.1.jar"],
+            jar_sha256 = "55d78aafa930693856055e7d1d63414670beb59a9b253ece5cf546541b4bbd07",
+            srcjar_urls = ["http://central.maven.org/maven2/com/salesforce/servicelibs/jprotoc/0.9.1/jprotoc-0.9.1-sources.jar"],
+            srcjar_sha256 = "ba023a2097874fa7131c277eab69ca748928627bea122a48ef9cb54ca8dafd91",
+            licenses = ["notice"],  # BSD 3-Clause
+        )
+
+    if not omit_com_github_spullara_mustache_java_compiler:
+        java_import_external(
+            name = "com_github_spullara_mustache_java_compiler",
+            jar_urls = ["http://central.maven.org/maven2/com/github/spullara/mustache/java/compiler/0.9.6/compiler-0.9.6.jar"],
+            jar_sha256 = "c4d697fd3619cb616cc5e22e9530c8a4fd4a8e9a76953c0655ee627cb2d22318",
+            srcjar_urls = ["http://central.maven.org/maven2/com/github/spullara/mustache/java/compiler/0.9.6/compiler-0.9.6-sources.jar"],
+            srcjar_sha256 = "fb3cf89e4daa0aaa4e659aca12a8ddb0d7b605271285f3e108201e0a389b4c7a",
+            licenses = ["notice"],  # Apache 2.0
+        )

bazel/java_reactive_grpc_library.bzl

@@ -0,0 +1,11 @@
+java_library(
+    name = "reactive-grpc-common",
+    srcs = glob(["src/main/**/*.java"]),
+    visibility = ["//visibility:public"],
+    deps = [
+        "@com_google_guava_guava",
+        "@io_grpc_grpc_java//core",
+        "@io_grpc_grpc_java//stub",
+        "@org_reactivestreams_reactive_streams",
+    ],
+)

bazel/repositories.bzl

@@ -0,0 +1,12 @@
+java_library(
+    name = "reactive-grpc-gencommon",
+    srcs = glob(["src/main/**/*.java"]),
+    visibility = ["//visibility:public"],
+    deps = [
+        "@com_salesforce_servicelibs_jprotoc",
+        "@com_github_spullara_mustache_java_compiler",
+        "@io_grpc_grpc_java//protobuf",
+        "@com_google_guava_guava",
+        "@com_google_protobuf//:protobuf_java",
+    ],
+)

common/reactive-grpc-common/BUILD.bazel

@@ -0,0 +1,5 @@
+# Required because by default Bazel strips source code info from proto file descriptors
+# (see https://github.com/bazelbuild/bazel/issues/3971)
+# and com.salesforce.reactivegrpc.gen.ReactiveGrpcGenerator does not generate any
+# services without source code info present
+build --protocopt=--include_source_info

common/reactive-grpc-gencommon/BUILD.bazel

@@ -0,0 +1,50 @@
+# Bazel Reactive gRPC
+
+This demo shows how to use the Reactive-gRPC Bazel rules.
+
+## Setup
+
+Add `build --protocopt=--include_source_info` to your `.bazelrc` file.
+This needs to be done because by default Bazel strips source code info from proto file descriptors. 
+This information is required by the Reactive-gRPC generator, **it does not generate services without it**.
+
+Include this project as an external dependency in your `WORKSPACE`.
+
+    load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+    http_archive(
+        name = "com_salesforce_servicelibs_reactive_grpc",
+        sha256 = <sha256>,
+        strip_prefix = "reactive-grpc-%s" % <version>,
+        url = "https://github.com/salesforce/reactive-grpc/archive/%s.zip" % <version>,
+    )
+
+    load("@com_salesforce_servicelibs_reactive_grpc//bazel:repositories.bzl", reactive_grpc_repositories="repositories")
+    reactive_grpc_repositories()
+    
+    load("@io_grpc_grpc_java//:repositories.bzl", "grpc_java_repositories")
+    grpc_java_repositories()
+
+
+In your build files use the following to generate reactive bindings.
+
+
+    load("@com_salesforce_servicelibs_reactive_grpc//bazel:java_reactive_grpc_library.bzl", "reactor_grpc_library", "rx_grpc_library")
+    
+    reactor_grpc_library(
+        name = "helloworld_reactor_grpc",
+        proto = ":helloworld_proto",
+        visibility = ["//visibility:public"],
+        deps = [":helloworld_java_grpc"],
+    )
+    
+    rx_grpc_library(
+        name = "helloworld_rx_grpc",
+        proto = ":helloworld_proto",
+        visibility = ["//visibility:public"],
+        deps = [":helloworld_java_grpc"],
+    )
+
+These targets can be used like any other `java_library` targets.
+Via the `deps` attribute they depend on their respective `java_grpc_library` targets.
+For more information on creating these see https://github.com/grpc/grpc-java.

demos/bazel/.bazelrc

@@ -0,0 +1,14 @@
+workspace(name = "com_salesforce_servicelibs_reactive_grpc_demos_bazel")
+
+local_repository(
+    name = "com_salesforce_servicelibs_reactive_grpc",
+    path = "../.."
+)
+
+load("@com_salesforce_servicelibs_reactive_grpc//bazel:repositories.bzl", "repositories")
+
+repositories()
+
+load("@io_grpc_grpc_java//:repositories.bzl", "grpc_java_repositories")
+
+grpc_java_repositories()

demos/bazel/BUILD.bazel

@@ -0,0 +1,21 @@
+java_library(
+    name = "reactivegrpc",
+    srcs = glob(["*.java"]),
+    visibility = ["//src/test:__subpackages__"],
+    deps = [
+        "//src/main/proto:helloworld_java_grpc",
+        "//src/main/proto:helloworld_java_proto",
+        "//src/main/proto:helloworld_rx_grpc",
+        "//src/main/proto:nested_java_proto",
+        "//src/main/proto:nested_rx_grpc",
+        "@io_grpc_grpc_java//core",
+        "@io_grpc_grpc_java//core:inprocess",
+        "@io_reactivex_rxjava2_rxjava",
+    ],
+)
+
+java_binary(
+    name = "reactivegrpc_bin",
+    main_class = "com.salesforce.servicelibs.reactivegrpc.BazelProof",
+    runtime_deps = [":reactivegrpc"],
+)