Support HEAD request in transcoding

WORKSPACE

@@ -26,7 +26,7 @@
 #
 # A Bazel (http://bazel.io) workspace for the Google Cloud Endpoints runtime.
 
-ISTIO_PROXY = "8b3a4429965ed1e792704e795e5d22782eca505b"
+ISTIO_PROXY = "ee3cdeeb33b1de0b87c80809802de5246cbb3e25"
 
 git_repository(
     name = "nginx",

src/nginx/grpc_server_call.cc

@@ -78,6 +78,11 @@ void TrimFront(std::vector<gpr_slice> *slices, size_t count) {
 // returns NGX_AGAIN.
 ngx_int_t ngx_esp_write_output(ngx_http_request_t *r, ngx_chain_t *out,
                                ngx_http_event_handler_pt write_event_handler) {
+  // Don't write response body if the request is HEAD
+  if (r->header_only) {
+    return NGX_OK;
+  }
+
   ngx_int_t rc = ngx_http_output_filter(r, out);
 
   if (rc == NGX_OK) {

src/nginx/t/BUILD

@@ -280,6 +280,7 @@ nginx_suite(
         "transcoding_bindings.t",
         "transcoding_deep_struct.t",
         "transcoding_errors.t",
+        "transcoding_head.t",
         "transcoding_ignore_unknown_fields.t",
         "transcoding_large.t",
         "transcoding_metadata.t",

src/nginx/t/transcoding_head.t

@@ -0,0 +1,204 @@
+# Copyright (C) Extensible Service Proxy Authors
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+################################################################################
+#
+use strict;
+use warnings;
+
+################################################################################
+
+use src::nginx::t::ApiManager;   # Must be first (sets up import path to the Nginx test module)
+use src::nginx::t::HttpServer;
+use src::nginx::t::ServiceControl;
+use Test::Nginx;  # Imports Nginx's test module
+use Test::More;   # And the test framework
+use JSON::PP;
+
+################################################################################
+
+# Port assignments
+my $NginxPort = ApiManager::pick_port();
+my $ServiceControlPort = ApiManager::pick_port();
+my $GrpcServerPort = ApiManager::pick_port();
+
+my $t = Test::Nginx->new()->has(qw/http proxy/)->plan(13);
+
+$t->write_file('service.pb.txt',
+  ApiManager::get_transcoding_test_service_config(
+    'endpoints-transcoding-test.cloudendpointsapis.com',
+    "http://127.0.0.1:${ServiceControlPort}") .
+    ApiManager::read_test_file('testdata/logs_metrics.pb.txt'));
+
+$t->write_file('server_config.pb.txt', ApiManager::disable_service_control_cache);
+
+$t->write_file_expand('nginx.conf', <<EOF);
+%%TEST_GLOBALS%%
+daemon off;
+events {
+  worker_connections 32;
+}
+http {
+  %%TEST_GLOBALS_HTTP%%
+  server_tokens off;
+  server {
+    listen 127.0.0.1:${NginxPort};
+    server_name localhost;
+    location / {
+      endpoints {
+        api service.pb.txt;
+        server_config server_config.pb.txt;
+        on;
+      }
+      grpc_pass 127.0.0.1:${GrpcServerPort};
+    }
+  }
+}
+EOF
+
+my $report_done = 'report_done';
+
+$t->run_daemon(\&service_control, $t, $ServiceControlPort, 'servicecontrol.log', $report_done);
+ApiManager::run_transcoding_test_server($t, 'server.log', "127.0.0.1:${GrpcServerPort}");
+
+is($t->waitforsocket("127.0.0.1:${ServiceControlPort}"), 1, "Service control socket ready.");
+is($t->waitforsocket("127.0.0.1:${GrpcServerPort}"), 1, "GRPC test server socket ready.");
+$t->run();
+is($t->waitforsocket("127.0.0.1:${NginxPort}"), 1, "Nginx socket ready.");
+
+################################################################################
+
+my $shelves_response = ApiManager::http($NginxPort, <<EOF);
+HEAD /shelves?key=api-key HTTP/1.0
+Host: localhost
+
+EOF
+
+# Wait for the service control report
+is($t->waitforfile("$t->{_testdir}/${report_done}"), 1, 'Report body file ready.');
+$t->stop_daemons();
+
+# Check the requests that the backend has received
+my $shelves_request_expected = {};
+
+my $server_output = $t->read_file('server.log');
+my @server_requests = split /\r\n\r\n/, $server_output;
+
+ok(ApiManager::compare_json($server_requests[0], $shelves_request_expected), 'Server received request');
+
+my ($headers, $actual_body) = split /\r\n\r\n/, $shelves_response, 2;
+like($headers, qr/HTTP\/1\.1 200 OK/, 'Returned HTTP 200.');
+like($headers, qr/Content-Type: application\/json/, 'Returned Content-Type');
+is('', $actual_body, 'Response body is empty');
+
+# Expect 2 service control calls for 1 requests.
+my @servicecontrol_requests = ApiManager::read_http_stream($t, 'servicecontrol.log');
+is(scalar @servicecontrol_requests, 2, 'Service control was called 2 times');
+
+while (my ($i, $r) = each @servicecontrol_requests) {
+  if ($i % 2 == 0) {
+    like($r->{uri}, qr/:check$/, "Check has correct uri for ${i}");
+  } else {
+    like($r->{uri}, qr/:report$/, "Report has correct uri for ${i}");
+  }
+}
+
+# :check
+my $r = shift @servicecontrol_requests;
+my $check_body = ServiceControl::convert_proto($r->{body}, 'check_request', 'json');
+my $expected_check_body = {
+  'serviceName' => 'endpoints-transcoding-test.cloudendpointsapis.com',
+  'serviceConfigId' => '2016-08-25r1',
+  'operation' => {
+     'consumerId' => 'api_key:api-key',
+     'operationName' => 'endpoints.examples.bookstore.Bookstore.ListShelves',
+     'labels' => {
+        'servicecontrol.googleapis.com/caller_ip' => '127.0.0.1',
+        'servicecontrol.googleapis.com/service_agent' => ServiceControl::service_agent(),
+        'servicecontrol.googleapis.com/user_agent' => 'ESP',
+     }
+  }
+};
+ok(ServiceControl::compare_json($check_body, $expected_check_body), 'Check body is received.');
+
+# :report
+$r = shift @servicecontrol_requests;
+my $report_body = ServiceControl::convert_proto($r->{body}, 'report_request', 'json');
+my $expected_report_body = ServiceControl::gen_report_body({
+  'serviceName' => 'endpoints-transcoding-test.cloudendpointsapis.com',
+  'api_method' => 'endpoints.examples.bookstore.Bookstore.ListShelves',
+  'serviceConfigId' => '2016-08-25r1',
+  'url' => '/shelves?key=api-key',
+  'api_key' => 'api-key',
+  'producer_project_id' => 'endpoints-transcoding-test',
+  'location' => 'us-central1',
+  'api_name' =>  'endpoints.examples.bookstore.Bookstore',
+  'api_version' =>  'v1',
+  'http_method' => 'HEAD',
+  'log_message' => 'Method: endpoints.examples.bookstore.Bookstore.ListShelves',
+  'response_code' => '200',
+  'request_size' => 52,
+  'response_size' => 122,
+  'request_bytes' => 52,
+  'response_bytes' => 122,
+  'streaming_request_message_counts' => 1,
+  'streaming_response_message_counts' => 1,
+  });
+ok(ServiceControl::compare_json($report_body, $expected_report_body), 'Report body is received.');
+
+################################################################################
+
+sub service_control {
+  my ($t, $port, $file, $done) = @_;
+
+  my $server = HttpServer->new($port, $t->testdir() . '/' . $file)
+    or die "Can't create test server socket: $!\n";
+
+  local $SIG{PIPE} = 'IGNORE';
+
+  $server->on_sub('POST', '/v1/services/endpoints-transcoding-test.cloudendpointsapis.com:check', sub {
+    my ($headers, $body, $client) = @_;
+    print $client <<EOF;
+HTTP/1.1 200 OK
+Content-Type: application/json
+Connection: close
+
+EOF
+  });
+
+  $server->on_sub('POST', '/v1/services/endpoints-transcoding-test.cloudendpointsapis.com:report', sub {
+    my ($headers, $body, $client) = @_;
+    print $client <<EOF;
+HTTP/1.1 200 OK
+Content-Type: application/json
+Connection: close
+
+EOF
+    $t->write_file($done, ":report done");
+  });
+
+  $server->run();
+}
+
+################################################################################