Kafka codec (#4950)

Signed-off-by: Adam Kotwasinski <adam.kotwasinski@gmail.com>

Mirrored from https://github.com/envoyproxy/envoy @ ecf1085a5b279d1244a02433f204ebba5306d40f

bazel/repositories.bzl

@@ -31,6 +31,11 @@ def api_dependencies():
         locations = REPOSITORY_LOCATIONS,
         build_file_content = OPENCENSUSTRACE_BUILD_CONTENT,
     )
+    envoy_http_archive(
+        name = "kafka_source",
+        locations = REPOSITORY_LOCATIONS,
+        build_file_content = KAFKASOURCE_BUILD_CONTENT,
+    )
 
 GOOGLEAPIS_BUILD_CONTENT = """
 load("@com_google_protobuf//:protobuf.bzl", "cc_proto_library", "py_proto_library")
@@ -286,3 +291,15 @@ go_proto_library(
     visibility = ["//visibility:public"],
 )
 """
+
+KAFKASOURCE_BUILD_CONTENT = """
+
+filegroup(
+    name = "request_protocol_files",
+    srcs = glob([
+        "*Request.json",
+    ]),
+    visibility = ["//visibility:public"],
+)
+
+"""

bazel/repository_locations.bzl

@@ -16,6 +16,8 @@ GOOGLEAPIS_SHA = "16f5b2e8bf1e747a32f9a62e211f8f33c94645492e9bbd72458061d9a9de1f
 PROMETHEUS_GIT_SHA = "99fa1f4be8e564e8a6b613da7fa6f46c9edafc6c"  # Nov 17, 2017
 PROMETHEUS_SHA = "783bdaf8ee0464b35ec0c8704871e1e72afa0005c3f3587f65d9d6694bf3911b"
 
+KAFKA_SOURCE_SHA = "ae7a1696c0a0302b43c5b21e515c37e6ecd365941f68a510a7e442eebddf39a1"  # 2.2.0-rc2
+
 REPOSITORY_LOCATIONS = dict(
     bazel_skylib = dict(
         sha256 = BAZEL_SKYLIB_SHA256,
@@ -48,4 +50,9 @@ REPOSITORY_LOCATIONS = dict(
         strip_prefix = "opencensus-proto-" + OPENCENSUS_RELEASE + "/src/opencensus/proto/trace/v1",
         urls = ["https://github.com/census-instrumentation/opencensus-proto/archive/v" + OPENCENSUS_RELEASE + ".tar.gz"],
     ),
+    kafka_source = dict(
+        sha256 = KAFKA_SOURCE_SHA,
+        strip_prefix = "kafka-2.2.0-rc2/clients/src/main/resources/common/message",
+        urls = ["https://github.com/apache/kafka/archive/2.2.0-rc2.zip"],
+    ),
 )