Adding Fake headers for header matching.

michaelywg · Jul 15, 2020 · 8c013bf · 8c013bf
1 parent 9b215e9
commit 8c013bf
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Showing 20 changed files with 413 additions and 42 deletions.
diff --git a/BUILD b/BUILD
@@ -1165,6 +1165,20 @@ grpc_cc_library(
     ],
 )
 
+grpc_cc_library(
+    name = "grpc_http_util",
+    srcs = [
+        "src/core/ext/filters/http/client/util.cc",
+    ],
+    hdrs = [
+        "src/core/ext/filters/http/client/util.h",
+    ],
+    language = "c++",
+    deps = [
+        "grpc_base",
+    ],
+)
+
 grpc_cc_library(
     name = "grpc_http_filters",
     srcs = [
@@ -1183,6 +1197,7 @@ grpc_cc_library(
     language = "c++",
     deps = [
         "grpc_base",
+        "grpc_http_util",
         "grpc_message_size_filter",
     ],
 )
@@ -1462,6 +1477,7 @@ grpc_cc_library(
     deps = [
         "grpc_base",
         "grpc_client_channel",
+        "grpc_http_util",
         "grpc_resolver_xds_header",
         "grpc_xds_api_header",
     ],

diff --git a/BUILD.gn b/BUILD.gn
@@ -320,6 +320,8 @@ config("grpc_config") {
         "src/core/ext/filters/deadline/deadline_filter.h",
         "src/core/ext/filters/http/client/http_client_filter.cc",
         "src/core/ext/filters/http/client/http_client_filter.h",
+        "src/core/ext/filters/http/client/util.cc",
+        "src/core/ext/filters/http/client/util.h",
         "src/core/ext/filters/http/client_authority_filter.cc",
         "src/core/ext/filters/http/client_authority_filter.h",
         "src/core/ext/filters/http/http_filters_plugin.cc",

diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -1396,6 +1396,7 @@ add_library(grpc
   src/core/ext/filters/client_idle/client_idle_filter.cc
   src/core/ext/filters/deadline/deadline_filter.cc
   src/core/ext/filters/http/client/http_client_filter.cc
+  src/core/ext/filters/http/client/util.cc
   src/core/ext/filters/http/client_authority_filter.cc
   src/core/ext/filters/http/http_filters_plugin.cc
   src/core/ext/filters/http/message_compress/message_compress_filter.cc
@@ -2140,6 +2141,7 @@ add_library(grpc_unsecure
   src/core/ext/filters/client_idle/client_idle_filter.cc
   src/core/ext/filters/deadline/deadline_filter.cc
   src/core/ext/filters/http/client/http_client_filter.cc
+  src/core/ext/filters/http/client/util.cc
   src/core/ext/filters/http/client_authority_filter.cc
   src/core/ext/filters/http/http_filters_plugin.cc
   src/core/ext/filters/http/message_compress/message_compress_filter.cc

diff --git a/Makefile b/Makefile
@@ -3462,6 +3462,7 @@ LIBGRPC_SRC = \
     src/core/ext/filters/client_idle/client_idle_filter.cc \
     src/core/ext/filters/deadline/deadline_filter.cc \
     src/core/ext/filters/http/client/http_client_filter.cc \
+    src/core/ext/filters/http/client/util.cc \
     src/core/ext/filters/http/client_authority_filter.cc \
     src/core/ext/filters/http/http_filters_plugin.cc \
     src/core/ext/filters/http/message_compress/message_compress_filter.cc \
@@ -4175,6 +4176,7 @@ LIBGRPC_UNSECURE_SRC = \
     src/core/ext/filters/client_idle/client_idle_filter.cc \
     src/core/ext/filters/deadline/deadline_filter.cc \
     src/core/ext/filters/http/client/http_client_filter.cc \
+    src/core/ext/filters/http/client/util.cc \
     src/core/ext/filters/http/client_authority_filter.cc \
     src/core/ext/filters/http/http_filters_plugin.cc \
     src/core/ext/filters/http/message_compress/message_compress_filter.cc \

diff --git a/build_autogenerated.yaml b/build_autogenerated.yaml
@@ -426,6 +426,7 @@ libs:
   - src/core/ext/filters/client_channel/xds/xds_client_stats.h
   - src/core/ext/filters/deadline/deadline_filter.h
   - src/core/ext/filters/http/client/http_client_filter.h
+  - src/core/ext/filters/http/client/util.h
   - src/core/ext/filters/http/client_authority_filter.h
   - src/core/ext/filters/http/message_compress/message_compress_filter.h
   - src/core/ext/filters/http/message_compress/message_decompress_filter.h
@@ -874,6 +875,7 @@ libs:
   - src/core/ext/filters/client_idle/client_idle_filter.cc
   - src/core/ext/filters/deadline/deadline_filter.cc
   - src/core/ext/filters/http/client/http_client_filter.cc
+  - src/core/ext/filters/http/client/util.cc
   - src/core/ext/filters/http/client_authority_filter.cc
   - src/core/ext/filters/http/http_filters_plugin.cc
   - src/core/ext/filters/http/message_compress/message_compress_filter.cc
@@ -1487,6 +1489,7 @@ libs:
   - src/core/ext/filters/client_channel/xds/xds_client_stats.h
   - src/core/ext/filters/deadline/deadline_filter.h
   - src/core/ext/filters/http/client/http_client_filter.h
+  - src/core/ext/filters/http/client/util.h
   - src/core/ext/filters/http/client_authority_filter.h
   - src/core/ext/filters/http/message_compress/message_compress_filter.h
   - src/core/ext/filters/http/message_compress/message_decompress_filter.h
@@ -1871,6 +1874,7 @@ libs:
   - src/core/ext/filters/client_idle/client_idle_filter.cc
   - src/core/ext/filters/deadline/deadline_filter.cc
   - src/core/ext/filters/http/client/http_client_filter.cc
+  - src/core/ext/filters/http/client/util.cc
   - src/core/ext/filters/http/client_authority_filter.cc
   - src/core/ext/filters/http/http_filters_plugin.cc
   - src/core/ext/filters/http/message_compress/message_compress_filter.cc

diff --git a/config.m4 b/config.m4
@@ -106,6 +106,7 @@ if test "$PHP_GRPC" != "no"; then
     src/core/ext/filters/client_idle/client_idle_filter.cc \
     src/core/ext/filters/deadline/deadline_filter.cc \
     src/core/ext/filters/http/client/http_client_filter.cc \
+    src/core/ext/filters/http/client/util.cc \
     src/core/ext/filters/http/client_authority_filter.cc \
     src/core/ext/filters/http/http_filters_plugin.cc \
     src/core/ext/filters/http/message_compress/message_compress_filter.cc \

diff --git a/config.w32 b/config.w32
@@ -74,6 +74,7 @@ if (PHP_GRPC != "no") {
     "src\\core\\ext\\filters\\client_idle\\client_idle_filter.cc " +
     "src\\core\\ext\\filters\\deadline\\deadline_filter.cc " +
     "src\\core\\ext\\filters\\http\\client\\http_client_filter.cc " +
+    "src\\core\\ext\\filters\\http\\client\\util.cc " +
     "src\\core\\ext\\filters\\http\\client_authority_filter.cc " +
     "src\\core\\ext\\filters\\http\\http_filters_plugin.cc " +
     "src\\core\\ext\\filters\\http\\message_compress\\message_compress_filter.cc " +

diff --git a/gRPC-C++.podspec b/gRPC-C++.podspec
@@ -271,6 +271,7 @@ Pod::Spec.new do |s|
                       'src/core/ext/filters/client_channel/xds/xds_client_stats.h',
                       'src/core/ext/filters/deadline/deadline_filter.h',
                       'src/core/ext/filters/http/client/http_client_filter.h',
+                      'src/core/ext/filters/http/client/util.h',
                       'src/core/ext/filters/http/client_authority_filter.h',
                       'src/core/ext/filters/http/message_compress/message_compress_filter.h',
                       'src/core/ext/filters/http/message_compress/message_decompress_filter.h',
@@ -829,6 +830,7 @@ Pod::Spec.new do |s|
                               'src/core/ext/filters/client_channel/xds/xds_client_stats.h',
                               'src/core/ext/filters/deadline/deadline_filter.h',
                               'src/core/ext/filters/http/client/http_client_filter.h',
+                              'src/core/ext/filters/http/client/util.h',
                               'src/core/ext/filters/http/client_authority_filter.h',
                               'src/core/ext/filters/http/message_compress/message_compress_filter.h',
                               'src/core/ext/filters/http/message_compress/message_decompress_filter.h',

diff --git a/gRPC-Core.podspec b/gRPC-Core.podspec
@@ -304,6 +304,8 @@ Pod::Spec.new do |s|
                       'src/core/ext/filters/deadline/deadline_filter.h',
                       'src/core/ext/filters/http/client/http_client_filter.cc',
                       'src/core/ext/filters/http/client/http_client_filter.h',
+                      'src/core/ext/filters/http/client/util.cc',
+                      'src/core/ext/filters/http/client/util.h',
                       'src/core/ext/filters/http/client_authority_filter.cc',
                       'src/core/ext/filters/http/client_authority_filter.h',
                       'src/core/ext/filters/http/http_filters_plugin.cc',
@@ -1293,6 +1295,7 @@ Pod::Spec.new do |s|
                               'src/core/ext/filters/client_channel/xds/xds_client_stats.h',
                               'src/core/ext/filters/deadline/deadline_filter.h',
                               'src/core/ext/filters/http/client/http_client_filter.h',
+                              'src/core/ext/filters/http/client/util.h',
                               'src/core/ext/filters/http/client_authority_filter.h',
                               'src/core/ext/filters/http/message_compress/message_compress_filter.h',
                               'src/core/ext/filters/http/message_compress/message_decompress_filter.h',

diff --git a/grpc.gemspec b/grpc.gemspec
@@ -226,6 +226,8 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/ext/filters/deadline/deadline_filter.h )
   s.files += %w( src/core/ext/filters/http/client/http_client_filter.cc )
   s.files += %w( src/core/ext/filters/http/client/http_client_filter.h )
+  s.files += %w( src/core/ext/filters/http/client/util.cc )
+  s.files += %w( src/core/ext/filters/http/client/util.h )
   s.files += %w( src/core/ext/filters/http/client_authority_filter.cc )
   s.files += %w( src/core/ext/filters/http/client_authority_filter.h )
   s.files += %w( src/core/ext/filters/http/http_filters_plugin.cc )

diff --git a/grpc.gyp b/grpc.gyp
@@ -503,6 +503,7 @@
         'src/core/ext/filters/client_idle/client_idle_filter.cc',
         'src/core/ext/filters/deadline/deadline_filter.cc',
         'src/core/ext/filters/http/client/http_client_filter.cc',
+        'src/core/ext/filters/http/client/util.cc',
         'src/core/ext/filters/http/client_authority_filter.cc',
         'src/core/ext/filters/http/http_filters_plugin.cc',
         'src/core/ext/filters/http/message_compress/message_compress_filter.cc',
@@ -1078,6 +1079,7 @@
         'src/core/ext/filters/client_idle/client_idle_filter.cc',
         'src/core/ext/filters/deadline/deadline_filter.cc',
         'src/core/ext/filters/http/client/http_client_filter.cc',
+        'src/core/ext/filters/http/client/util.cc',
         'src/core/ext/filters/http/client_authority_filter.cc',
         'src/core/ext/filters/http/http_filters_plugin.cc',
         'src/core/ext/filters/http/message_compress/message_compress_filter.cc',

diff --git a/package.xml b/package.xml
@@ -206,6 +206,8 @@
     <file baseinstalldir="/" name="src/core/ext/filters/deadline/deadline_filter.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/http/client/http_client_filter.cc" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/http/client/http_client_filter.h" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/filters/http/client/util.cc" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/filters/http/client/util.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/http/client_authority_filter.cc" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/http/client_authority_filter.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/http/http_filters_plugin.cc" role="src" />

diff --git a/src/core/ext/filters/client_channel/lb_policy/xds/xds_routing.cc b/src/core/ext/filters/client_channel/lb_policy/xds/xds_routing.cc
@@ -35,6 +35,7 @@
 #include "src/core/ext/filters/client_channel/lb_policy_registry.h"
 #include "src/core/ext/filters/client_channel/resolver/xds/xds_resolver.h"
 #include "src/core/ext/filters/client_channel/xds/xds_api.h"
+#include "src/core/ext/filters/http/client/util.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/gpr/string.h"
 #include "src/core/lib/gprpp/orphanable.h"
@@ -117,14 +118,18 @@ class XdsRoutingLb : public LoadBalancingPolicy {
     // Maintains an ordered xds route table as provided by RDS response.
     using RouteTable = std::vector<Route>;
 
-    explicit RoutePicker(RouteTable route_table,
-                         RefCountedPtr<XdsRoutingLbConfig> config)
-        : route_table_(std::move(route_table)), config_(std::move(config)) {}
+    RoutePicker(RouteTable route_table, std::string user_agent,
+                RefCountedPtr<XdsRoutingLbConfig> config)
+        : route_table_(std::move(route_table)),
+          user_agent_(std::move(user_agent)),
+          config_(std::move(config)) {}
 
     PickResult Pick(PickArgs args) override;
 
    private:
     RouteTable route_table_;
+    // Storing user_agent generated from args from http layer.
+    std::string user_agent_;
     // Take a reference to config so that we can use
     // XdsApi::RdsUpdate::RdsRoute::Matchers from it.
     RefCountedPtr<XdsRoutingLbConfig> config_;
@@ -213,6 +218,9 @@ class XdsRoutingLb : public LoadBalancingPolicy {
 
   // Children.
   std::map<std::string, OrphanablePtr<XdsRoutingChild>> actions_;
+
+  // Storing user_agent generated from args from http layer.
+  std::string user_agent_;
 };
 
 //
@@ -254,8 +262,22 @@ bool PathMatch(
 
 bool HeaderMatchHelper(
     const XdsApi::RdsUpdate::RdsRoute::Matchers::HeaderMatcher& header_matcher,
-    LoadBalancingPolicy::MetadataInterface* initial_metadata) {
-  auto value = GetMetadataValue(header_matcher.name, initial_metadata);
+    LoadBalancingPolicy::MetadataInterface* initial_metadata,
+    const std::string& user_agent, absl::string_view deadline) {
+  absl::optional<absl::string_view> value;
+  if (header_matcher.name == "grpc-tags-bin" ||
+      header_matcher.name == "grpc-trace-bin" ||
+      header_matcher.name == "grpc-previous-rpc-attempts") {
+    value = absl::nullopt;
+  } else if (header_matcher.name == "content-type") {
+    value = "application/grpc";
+  } else if (header_matcher.name == "user-agent") {
+    value = user_agent;
+  } else if (header_matcher.name == "grpc-timeout") {
+    value = deadline;
+  } else {
+    value = GetMetadataValue(header_matcher.name, initial_metadata);
+  }
   if (!value.has_value()) {
     if (header_matcher.type == XdsApi::RdsUpdate::RdsRoute::Matchers::
                                    HeaderMatcher::HeaderMatcherType::PRESENT) {
@@ -293,11 +315,13 @@ bool HeaderMatchHelper(
 }
 
 bool HeadersMatch(
-    LoadBalancingPolicy::PickArgs args,
     const std::vector<XdsApi::RdsUpdate::RdsRoute::Matchers::HeaderMatcher>&
-        header_matchers) {
+        header_matchers,
+    LoadBalancingPolicy::MetadataInterface* initial_metadata,
+    const std::string& user_agent, absl::string_view deadline) {
   for (const auto& header_matcher : header_matchers) {
-    bool match = HeaderMatchHelper(header_matcher, args.initial_metadata);
+    bool match = HeaderMatchHelper(header_matcher, initial_metadata, user_agent,
+                                   deadline);
     if (header_matcher.invert_match) match = !match;
     if (!match) return false;
   }
@@ -315,11 +339,16 @@ XdsRoutingLb::PickResult XdsRoutingLb::RoutePicker::Pick(PickArgs args) {
     // Path matching.
     if (!PathMatch(args.path, route.matchers->path_matcher)) continue;
     // Header Matching.
-    if (!HeadersMatch(args, route.matchers->header_matchers)) continue;
+    if (!HeadersMatch(route.matchers->header_matchers, args.initial_metadata,
+                      user_agent_,
+                      args.call_state->ExperimentalGetCallAttribute(
+                          kCallAttributeDeadline)))
+      continue;
     // Match fraction check
     if (route.matchers->fraction_per_million.has_value() &&
-        !UnderFraction(route.matchers->fraction_per_million.value()))
+        !UnderFraction(route.matchers->fraction_per_million.value())) {
       continue;
+    }
     // Found a match
     return route.picker->Pick(args);
   }
@@ -336,7 +365,9 @@ XdsRoutingLb::PickResult XdsRoutingLb::RoutePicker::Pick(PickArgs args) {
 // XdsRoutingLb
 //
 
-XdsRoutingLb::XdsRoutingLb(Args args) : LoadBalancingPolicy(std::move(args)) {}
+XdsRoutingLb::XdsRoutingLb(Args args)
+    : LoadBalancingPolicy(std::move(args)),
+      user_agent_(GenerateUserAgentFromArgs(args.args, "chttp2")) {}
 
 XdsRoutingLb::~XdsRoutingLb() {
   if (GRPC_TRACE_FLAG_ENABLED(grpc_xds_routing_lb_trace)) {
@@ -461,7 +492,8 @@ void XdsRoutingLb::UpdateStateLocked() {
         }
         route_table.push_back(std::move(route));
       }
-      picker = absl::make_unique<RoutePicker>(std::move(route_table), config_);
+      picker = absl::make_unique<RoutePicker>(std::move(route_table),
+                                              user_agent_, config_);
       break;
     }
     case GRPC_CHANNEL_CONNECTING:

diff --git a/src/core/ext/filters/http/client/http_client_filter.cc b/src/core/ext/filters/http/client/http_client_filter.cc
@@ -31,6 +31,7 @@
 #include <grpc/support/log.h>
 
 #include "src/core/ext/filters/http/client/http_client_filter.h"
+#include "src/core/ext/filters/http/client/util.h"
 #include "src/core/lib/gpr/string.h"
 #include "src/core/lib/gprpp/manual_constructor.h"
 #include "src/core/lib/profiling/timers.h"
@@ -528,36 +529,8 @@ static size_t max_payload_size_from_args(const grpc_channel_args* args) {
 
 static grpc_core::ManagedMemorySlice user_agent_from_args(
     const grpc_channel_args* args, const char* transport_name) {
-  std::vector<std::string> user_agent_fields;
-
-  for (size_t i = 0; args && i < args->num_args; i++) {
-    if (0 == strcmp(args->args[i].key, GRPC_ARG_PRIMARY_USER_AGENT_STRING)) {
-      if (args->args[i].type != GRPC_ARG_STRING) {
-        gpr_log(GPR_ERROR, "Channel argument '%s' should be a string",
-                GRPC_ARG_PRIMARY_USER_AGENT_STRING);
-      } else {
-        user_agent_fields.push_back(args->args[i].value.string);
-      }
-    }
-  }
-
-  user_agent_fields.push_back(
-      absl::StrFormat("grpc-c/%s (%s; %s)", grpc_version_string(),
-                      GPR_PLATFORM_STRING, transport_name));
-
-  for (size_t i = 0; args && i < args->num_args; i++) {
-    if (0 == strcmp(args->args[i].key, GRPC_ARG_SECONDARY_USER_AGENT_STRING)) {
-      if (args->args[i].type != GRPC_ARG_STRING) {
-        gpr_log(GPR_ERROR, "Channel argument '%s' should be a string",
-                GRPC_ARG_SECONDARY_USER_AGENT_STRING);
-      } else {
-        user_agent_fields.push_back(args->args[i].value.string);
-      }
-    }
-  }
-
-  std::string user_agent_string = absl::StrJoin(user_agent_fields, " ");
-  return grpc_core::ManagedMemorySlice(user_agent_string.c_str());
+  return grpc_core::ManagedMemorySlice(
+      grpc_core::GenerateUserAgentFromArgs(args, transport_name).c_str());
 }
 
 /* Constructor for channel_data */