Add feature examples with continuous integration (#27917)

* Add failing end2end test for inconsistent percent-decoding of URIs

* Add passing h2_local_abstract_uds end2end tests

* Add basic abstract UDS example

* add test runner

* add proper bazel build path

* first attempt at CI configuration

* cleanup

* rename CI files for better readability

examples/cpp/features/run_tests.sh

@@ -0,0 +1,129 @@
+#!/usr/bin/env bash
+# Copyright 2021 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Test structure borrowed with gratitude from
+# https://github.com/grpc/grpc-go/tree/master/examples/features
+
+set -eux
+
+# execute in root dir
+SCRIPTPATH="$(
+  cd -- "$(dirname "$0")" >/dev/null 2>&1
+  pwd -P
+)"
+cd ${SCRIPTPATH}/../../..
+
+SERVER_PORT=50051
+
+export TMPDIR=$(mktemp -d)
+trap "rm -rf ${TMPDIR}" EXIT
+
+clean() {
+  # loop a handful of times in case job shutdown is not immediate
+  for i in {1..5}; do
+    # kill all jobs
+    jobs -p | xargs kill &>/dev/null || true
+    # wait for all jobs to exit
+    sleep 0.3
+    if ! jobs | read; then
+      return
+    fi
+  done
+  echo "ERROR: clean failed to kill tests"
+  jobs
+  exit 1
+}
+
+fail() {
+  echo "$@" >&2
+  clean
+  exit 1
+}
+
+pass() {
+  echo "SUCCESS: $1"
+}
+
+wait_for_server() {
+  feature=$1
+  wait_command=${SERVER_WAIT_COMMAND[$feature]:-${SERVER_WAIT_COMMAND["default"]}}
+  echo "INFO: waiting for server to start"
+  declare -i i=0
+  while ! eval "$wait_command"; do
+    ((++i < 10)) || fail "cannot determine if server started"
+    lsof -U
+    sleep 1
+  done
+  pass "server started"
+}
+
+FEATURES=(
+  "unix_abstract"
+)
+
+declare -A SERVER_WAIT_COMMAND=(
+  ["unix_abstract"]="lsof -U | grep '@grpc@abstract'"
+  ["default"]="lsof -i :$SERVER_PORT | grep $SERVER_PORT"
+)
+
+declare -A EXPECTED_SERVER_OUTPUT=(
+  ["unix_abstract"]="Server listening on unix-abstract:grpc%00abstract ... Echoing: arst"
+)
+
+declare -A EXPECTED_CLIENT_OUTPUT=(
+  ["unix_abstract"]="Sending 'arst' to unix-abstract:grpc%00abstract ... Received: arst"
+)
+
+for feature in ${FEATURES[@]}; do
+  echo "TESTING: $feature"
+  bazel build --define=use_strict_warning=true //examples/cpp/features/${feature}:all || fail "failed to build $feature"
+
+  SERVER_LOG="$(mktemp)"
+  ./bazel-bin/examples/cpp/features/$feature/server &>$SERVER_LOG &
+
+  wait_for_server $feature
+
+  # TODO(hork): add a timeout to abort client?
+  CLIENT_LOG="$(mktemp)"
+  ./bazel-bin/examples/cpp/features/$feature/client &>$CLIENT_LOG
+
+  if [ -n "${EXPECTED_SERVER_OUTPUT[$feature]}" ]; then
+    if ! grep -q "${EXPECTED_SERVER_OUTPUT[$feature]}" $SERVER_LOG; then
+      fail "server log missing output: ${EXPECTED_SERVER_OUTPUT[$feature]}
+      got server log:
+      $(cat $SERVER_LOG)
+      got client log:
+      $(cat $CLIENT_LOG)
+      "
+    else
+      pass "server log contains expected output: ${EXPECTED_SERVER_OUTPUT[$feature]}"
+    fi
+  fi
+
+  if [ -n "${EXPECTED_CLIENT_OUTPUT[$feature]}" ]; then
+    if ! grep -q "${EXPECTED_CLIENT_OUTPUT[$feature]}" $CLIENT_LOG; then
+      fail "client log missing output: ${EXPECTED_CLIENT_OUTPUT[$feature]}
+      got server log:
+      $(cat $SERVER_LOG)
+      got client log:
+      $(cat $CLIENT_LOG)
+      "
+    else
+      pass "client log contains expected output: ${EXPECTED_CLIENT_OUTPUT[$feature]}"
+    fi
+  fi
+
+  clean
+done

examples/cpp/features/unix_abstract/BUILD

@@ -0,0 +1,34 @@
+# Copyright 2021 the gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+licenses(["notice"])
+
+cc_binary(
+    name = "client",
+    srcs = ["client.cc"],
+    deps = [
+        "//:grpc++",
+        "//examples/protos:helloworld_cc_grpc",
+    ],
+)
+
+cc_binary(
+    name = "server",
+    srcs = ["server.cc"],
+    deps = [
+        "//:grpc++",
+        "//:grpc++_reflection",
+        "//examples/protos:helloworld_cc_grpc",
+    ],
+)

examples/cpp/features/unix_abstract/client.cc

@@ -0,0 +1,63 @@
+// Copyright 2021 the gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <iostream>
+#include <memory>
+#include <string>
+
+#include "examples/protos/helloworld.grpc.pb.h"
+
+#include <grpcpp/grpcpp.h>
+
+using grpc::Channel;
+using grpc::ClientContext;
+using grpc::Status;
+using helloworld::Greeter;
+using helloworld::HelloReply;
+using helloworld::HelloRequest;
+
+class GreeterClient {
+ public:
+  GreeterClient(std::shared_ptr<Channel> channel)
+      : stub_(Greeter::NewStub(channel)) {}
+
+  std::string SayHello(const std::string& user) {
+    HelloRequest request;
+    request.set_name(user);
+    HelloReply reply;
+    ClientContext context;
+    Status status = stub_->SayHello(&context, request, &reply);
+    if (status.ok()) {
+      return reply.message();
+    }
+    std::cout << status.error_code() << ": " << status.error_message()
+              << std::endl;
+    return "RPC failed";
+  }
+
+ private:
+  std::unique_ptr<Greeter::Stub> stub_;
+};
+
+int main(int argc, char** argv) {
+  std::string target_str("unix-abstract:grpc%00abstract");
+  GreeterClient greeter(
+      grpc::CreateChannel(target_str, grpc::InsecureChannelCredentials()));
+  std::string user("arst");
+  std::cout << "Sending '" << user << "' to " << target_str << " ... ";
+  std::string reply = greeter.SayHello(user);
+  std::cout << "Received: " << reply << std::endl;
+
+  return 0;
+}

examples/cpp/features/unix_abstract/server.cc

@@ -0,0 +1,60 @@
+// Copyright 2021 the gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <iostream>
+#include <memory>
+#include <string>
+
+#include "examples/protos/helloworld.grpc.pb.h"
+
+#include <grpcpp/ext/proto_server_reflection_plugin.h>
+#include <grpcpp/grpcpp.h>
+#include <grpcpp/health_check_service_interface.h>
+
+using grpc::Server;
+using grpc::ServerBuilder;
+using grpc::ServerContext;
+using grpc::Status;
+using helloworld::Greeter;
+using helloworld::HelloReply;
+using helloworld::HelloRequest;
+
+// Logic and data behind the server's behavior.
+class GreeterServiceImpl final : public Greeter::Service {
+  Status SayHello(ServerContext* context, const HelloRequest* request,
+                  HelloReply* reply) override {
+    reply->set_message(request->name());
+    std::cout << "Echoing: " << request->name() << std::endl;
+    return Status::OK;
+  }
+};
+
+void RunServer() {
+  std::string server_address("unix-abstract:grpc%00abstract");
+  GreeterServiceImpl service;
+  grpc::EnableDefaultHealthCheckService(true);
+  grpc::reflection::InitProtoReflectionServerBuilderPlugin();
+  ServerBuilder builder;
+  builder.AddListeningPort(server_address, grpc::InsecureServerCredentials());
+  builder.RegisterService(&service);
+  std::unique_ptr<Server> server(builder.BuildAndStart());
+  std::cout << "Server listening on " << server_address << " ... ";
+  server->Wait();
+}
+
+int main(int argc, char** argv) {
+  RunServer();
+
+  return 0;
+}

tools/internal_ci/linux/grpc_feature_example_tests.sh

@@ -0,0 +1,29 @@
+#!/bin/bash
+# Copyright 2021 The gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#!/usr/bin/env bash
+#
+# NOTE: No empty lines should appear in this file before igncr is set!
+set -ex -o igncr || set -ex
+
+mkdir -p /var/local/git
+git clone /var/local/jenkins/grpc /var/local/git/grpc
+(cd /var/local/jenkins/grpc/ && git submodule foreach 'cd /var/local/git/grpc \
+&& git submodule update --init --reference /var/local/jenkins/grpc/${name} \
+${name}')
+cd /var/local/git/grpc
+
+apt-get install -y lsof
+
+./examples/cpp/features/run_tests.sh

tools/internal_ci/linux/pull_request/grpc_feature_examples_test.cfg

@@ -0,0 +1,29 @@
+# Copyright 2019 The gRPC Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Config file for the internal CI (in protobuf text format)
+
+# Location of the continuous shell script in repository.
+build_file: "grpc/tools/internal_ci/linux/grpc_bazel.sh"
+timeout_mins: 30
+env_vars {
+  key: "BAZEL_SCRIPT"
+  value: "tools/internal_ci/linux/grpc_feature_example_tests.sh"
+}
+action {
+  define_artifacts {
+    regex: "**/*sponge_log.*"
+    regex: "github/grpc/reports/**"
+  }
+}