PollingResolver: clean up the way that ChannelArgs are passed in (#32430)

src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc

@@ -95,7 +95,7 @@ namespace {
 class AresClientChannelDNSResolver : public PollingResolver {
  public:
   AresClientChannelDNSResolver(ResolverArgs args,
-                               const ChannelArgs& channel_args);
+                               Duration min_time_between_resolutions);
 
   OrphanablePtr<Orphanable> StartRequest() override;
 
@@ -205,29 +205,26 @@ class AresClientChannelDNSResolver : public PollingResolver {
 };
 
 AresClientChannelDNSResolver::AresClientChannelDNSResolver(
-    ResolverArgs args, const ChannelArgs& channel_args)
-    : PollingResolver(
-          std::move(args), channel_args,
-          std::max(Duration::Zero(),
-                   channel_args
-                       .GetDurationFromIntMillis(
-                           GRPC_ARG_DNS_MIN_TIME_BETWEEN_RESOLUTIONS_MS)
-                       .value_or(Duration::Seconds(30))),
-          BackOff::Options()
-              .set_initial_backoff(Duration::Milliseconds(
-                  GRPC_DNS_INITIAL_CONNECT_BACKOFF_SECONDS * 1000))
-              .set_multiplier(GRPC_DNS_RECONNECT_BACKOFF_MULTIPLIER)
-              .set_jitter(GRPC_DNS_RECONNECT_JITTER)
-              .set_max_backoff(Duration::Milliseconds(
-                  GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000)),
-          &grpc_trace_cares_resolver),
+    ResolverArgs args, Duration min_time_between_resolutions)
+    : PollingResolver(std::move(args), min_time_between_resolutions,
+                      BackOff::Options()
+                          .set_initial_backoff(Duration::Milliseconds(
+                              GRPC_DNS_INITIAL_CONNECT_BACKOFF_SECONDS * 1000))
+                          .set_multiplier(GRPC_DNS_RECONNECT_BACKOFF_MULTIPLIER)
+                          .set_jitter(GRPC_DNS_RECONNECT_JITTER)
+                          .set_max_backoff(Duration::Milliseconds(
+                              GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000)),
+                      &grpc_trace_cares_resolver),
       request_service_config_(
-          !channel_args.GetBool(GRPC_ARG_SERVICE_CONFIG_DISABLE_RESOLUTION)
+          !channel_args()
+               .GetBool(GRPC_ARG_SERVICE_CONFIG_DISABLE_RESOLUTION)
                .value_or(true)),
-      enable_srv_queries_(channel_args.GetBool(GRPC_ARG_DNS_ENABLE_SRV_QUERIES)
+      enable_srv_queries_(channel_args()
+                              .GetBool(GRPC_ARG_DNS_ENABLE_SRV_QUERIES)
                               .value_or(false)),
       query_timeout_ms_(
-          std::max(0, channel_args.GetInt(GRPC_ARG_DNS_ARES_QUERY_TIMEOUT_MS)
+          std::max(0, channel_args()
+                          .GetInt(GRPC_ARG_DNS_ARES_QUERY_TIMEOUT_MS)
                           .value_or(GRPC_DNS_ARES_DEFAULT_QUERY_TIMEOUT_MS))) {}
 
 AresClientChannelDNSResolver::~AresClientChannelDNSResolver() {
@@ -460,9 +457,13 @@ class AresClientChannelDNSResolverFactory : public ResolverFactory {
   }
 
   OrphanablePtr<Resolver> CreateResolver(ResolverArgs args) const override {
-    ChannelArgs channel_args = args.args;
-    return MakeOrphanable<AresClientChannelDNSResolver>(std::move(args),
-                                                        channel_args);
+    Duration min_time_between_resolutions = std::max(
+        Duration::Zero(), args.args
+                              .GetDurationFromIntMillis(
+                                  GRPC_ARG_DNS_MIN_TIME_BETWEEN_RESOLUTIONS_MS)
+                              .value_or(Duration::Seconds(30)));
+    return MakeOrphanable<AresClientChannelDNSResolver>(
+        std::move(args), min_time_between_resolutions);
   }
 };
 

src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.cc

@@ -67,7 +67,7 @@ TraceFlag grpc_trace_dns_resolver(false, "dns_resolver");
 class NativeClientChannelDNSResolver : public PollingResolver {
  public:
   NativeClientChannelDNSResolver(ResolverArgs args,
-                                 const ChannelArgs& channel_args);
+                                 Duration min_time_between_resolutions);
   ~NativeClientChannelDNSResolver() override;
 
   OrphanablePtr<Orphanable> StartRequest() override;
@@ -88,22 +88,16 @@ class NativeClientChannelDNSResolver : public PollingResolver {
 };
 
 NativeClientChannelDNSResolver::NativeClientChannelDNSResolver(
-    ResolverArgs args, const ChannelArgs& channel_args)
-    : PollingResolver(
-          std::move(args), channel_args,
-          std::max(Duration::Zero(),
-                   channel_args
-                       .GetDurationFromIntMillis(
-                           GRPC_ARG_DNS_MIN_TIME_BETWEEN_RESOLUTIONS_MS)
-                       .value_or(Duration::Seconds(30))),
-          BackOff::Options()
-              .set_initial_backoff(Duration::Milliseconds(
-                  GRPC_DNS_INITIAL_CONNECT_BACKOFF_SECONDS * 1000))
-              .set_multiplier(GRPC_DNS_RECONNECT_BACKOFF_MULTIPLIER)
-              .set_jitter(GRPC_DNS_RECONNECT_JITTER)
-              .set_max_backoff(Duration::Milliseconds(
-                  GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000)),
-          &grpc_trace_dns_resolver) {
+    ResolverArgs args, Duration min_time_between_resolutions)
+    : PollingResolver(std::move(args), min_time_between_resolutions,
+                      BackOff::Options()
+                          .set_initial_backoff(Duration::Milliseconds(
+                              GRPC_DNS_INITIAL_CONNECT_BACKOFF_SECONDS * 1000))
+                          .set_multiplier(GRPC_DNS_RECONNECT_BACKOFF_MULTIPLIER)
+                          .set_jitter(GRPC_DNS_RECONNECT_JITTER)
+                          .set_max_backoff(Duration::Milliseconds(
+                              GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000)),
+                      &grpc_trace_dns_resolver) {
   if (GRPC_TRACE_FLAG_ENABLED(grpc_trace_dns_resolver)) {
     gpr_log(GPR_DEBUG, "[dns_resolver=%p] created", this);
   }
@@ -174,9 +168,13 @@ class NativeClientChannelDNSResolverFactory : public ResolverFactory {
 
   OrphanablePtr<Resolver> CreateResolver(ResolverArgs args) const override {
     if (!IsValidUri(args.uri)) return nullptr;
-    auto channel_args = args.args;
+    Duration min_time_between_resolutions = std::max(
+        Duration::Zero(), args.args
+                              .GetDurationFromIntMillis(
+                                  GRPC_ARG_DNS_MIN_TIME_BETWEEN_RESOLUTIONS_MS)
+                              .value_or(Duration::Seconds(30)));
     return MakeOrphanable<NativeClientChannelDNSResolver>(
-        std::move(args), std::move(channel_args));
+        std::move(args), min_time_between_resolutions);
   }
 };
 

src/core/ext/filters/client_channel/resolver/polling_resolver.cc

@@ -47,13 +47,12 @@ namespace grpc_core {
 using ::grpc_event_engine::experimental::EventEngine;
 
 PollingResolver::PollingResolver(ResolverArgs args,
-                                 const ChannelArgs& channel_args,
                                  Duration min_time_between_resolutions,
                                  BackOff::Options backoff_options,
                                  TraceFlag* tracer)
     : authority_(args.uri.authority()),
       name_to_resolve_(absl::StripPrefix(args.uri.path(), "/")),
-      channel_args_(channel_args),
+      channel_args_(std::move(args.args)),
       work_serializer_(std::move(args.work_serializer)),
       result_handler_(std::move(args.result_handler)),
       tracer_(tracer),

src/core/ext/filters/client_channel/resolver/polling_resolver.h

@@ -44,8 +44,7 @@ namespace grpc_core {
 // Implementations need only to implement StartRequest().
 class PollingResolver : public Resolver {
  public:
-  PollingResolver(ResolverArgs args, const ChannelArgs& channel_args,
-                  Duration min_time_between_resolutions,
+  PollingResolver(ResolverArgs args, Duration min_time_between_resolutions,
                   BackOff::Options backoff_options, TraceFlag* tracer);
   ~PollingResolver() override;