#19824

Committed 23 May 2025 09:18AM UTC coverage: 88.636% (-0.007%) from 88.643%

Build # #19824

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push

github

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web-flow

Commit Message

xds: float LRU cache across interceptors (#11992) (#12096)

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85.59

/../xds/src/main/java/io/grpc/xds/GcpAuthenticationFilter.java

/*
 * 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.
 */

package io.grpc.xds;

import static com.google.common.base.Preconditions.checkNotNull;
import static io.grpc.xds.XdsNameResolver.CLUSTER_SELECTION_KEY;
import static io.grpc.xds.XdsNameResolver.XDS_CONFIG_CALL_OPTION_KEY;

import com.google.auth.oauth2.ComputeEngineCredentials;
import com.google.auth.oauth2.IdTokenCredentials;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.primitives.UnsignedLongs;
import com.google.protobuf.Any;
import com.google.protobuf.InvalidProtocolBufferException;
import com.google.protobuf.Message;
import io.envoyproxy.envoy.extensions.filters.http.gcp_authn.v3.Audience;
import io.envoyproxy.envoy.extensions.filters.http.gcp_authn.v3.GcpAuthnFilterConfig;
import io.envoyproxy.envoy.extensions.filters.http.gcp_authn.v3.TokenCacheConfig;
import io.grpc.CallCredentials;
import io.grpc.CallOptions;
import io.grpc.Channel;
import io.grpc.ClientCall;
import io.grpc.ClientInterceptor;
import io.grpc.CompositeCallCredentials;
import io.grpc.Metadata;
import io.grpc.MethodDescriptor;
import io.grpc.Status;
import io.grpc.StatusOr;
import io.grpc.auth.MoreCallCredentials;
import io.grpc.xds.GcpAuthenticationFilter.AudienceMetadataParser.AudienceWrapper;
import io.grpc.xds.MetadataRegistry.MetadataValueParser;
import io.grpc.xds.XdsConfig.XdsClusterConfig;
import io.grpc.xds.client.XdsResourceType.ResourceInvalidException;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.concurrent.ScheduledExecutorService;
import java.util.function.Function;
import javax.annotation.Nullable;

/**
 * A {@link Filter} that injects a {@link CallCredentials} to handle
 * authentication for xDS credentials.
 */
final class GcpAuthenticationFilter implements Filter {

  static final String TYPE_URL =
      "type.googleapis.com/envoy.extensions.filters.http.gcp_authn.v3.GcpAuthnFilterConfig";
  private final LruCache<String, CallCredentials> callCredentialsCache;
  final String filterInstanceName;

  GcpAuthenticationFilter(String name, int cacheSize) {
    filterInstanceName = checkNotNull(name, "name");
    this.callCredentialsCache = new LruCache<>(cacheSize);
  }

  static final class Provider implements Filter.Provider {
    private final int cacheSize = 10;

    @Override
    public String[] typeUrls() {
      return new String[]{TYPE_URL};
    }

    @Override
    public boolean isClientFilter() {
      return true;
    }

    @Override
    public GcpAuthenticationFilter newInstance(String name) {
      return new GcpAuthenticationFilter(name, cacheSize);
    }

    @Override
    public ConfigOrError<GcpAuthenticationConfig> parseFilterConfig(Message rawProtoMessage) {
      GcpAuthnFilterConfig gcpAuthnProto;
      if (!(rawProtoMessage instanceof Any)) {
        return ConfigOrError.fromError("Invalid config type: " + rawProtoMessage.getClass());
      }
      Any anyMessage = (Any) rawProtoMessage;

      try {
        gcpAuthnProto = anyMessage.unpack(GcpAuthnFilterConfig.class);
      } catch (InvalidProtocolBufferException e) {
        return ConfigOrError.fromError("Invalid proto: " + e);
      }

      long cacheSize = 10;
      // Validate cache_config
      if (gcpAuthnProto.hasCacheConfig()) {
        TokenCacheConfig cacheConfig = gcpAuthnProto.getCacheConfig();
        if (cacheConfig.hasCacheSize()) {
          cacheSize = cacheConfig.getCacheSize().getValue();
          if (cacheSize == 0) {
            return ConfigOrError.fromError(
                "cache_config.cache_size must be greater than zero");
          }
        }

        // LruCache's size is an int and briefly exceeds its maximum size before evicting entries
        cacheSize = UnsignedLongs.min(cacheSize, Integer.MAX_VALUE - 1);
      }

      GcpAuthenticationConfig config = new GcpAuthenticationConfig((int) cacheSize);
      return ConfigOrError.fromConfig(config);
    }

    @Override
    public ConfigOrError<GcpAuthenticationConfig> parseFilterConfigOverride(
        Message rawProtoMessage) {
      return parseFilterConfig(rawProtoMessage);
    }
  }

  @Nullable
  @Override
  public ClientInterceptor buildClientInterceptor(FilterConfig config,
      @Nullable FilterConfig overrideConfig, ScheduledExecutorService scheduler) {

    ComputeEngineCredentials credentials = ComputeEngineCredentials.create();
    synchronized (callCredentialsCache) {
      callCredentialsCache.resizeCache(((GcpAuthenticationConfig) config).getCacheSize());
    }
    return new ClientInterceptor() {
      @Override
      public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(
          MethodDescriptor<ReqT, RespT> method, CallOptions callOptions, Channel next) {

        String clusterName = callOptions.getOption(CLUSTER_SELECTION_KEY);
        if (clusterName == null) {
          return new FailingClientCall<>(
              Status.UNAVAILABLE.withDescription(
                  String.format(
                      "GCP Authn for %s does not contain cluster resource", filterInstanceName)));
        }

        if (!clusterName.startsWith("cluster:")) {
          return next.newCall(method, callOptions);
        }
        XdsConfig xdsConfig = callOptions.getOption(XDS_CONFIG_CALL_OPTION_KEY);
        if (xdsConfig == null) {
          return new FailingClientCall<>(
              Status.UNAVAILABLE.withDescription(
                  String.format(
                      "GCP Authn for %s with %s does not contain xds configuration",
                      filterInstanceName, clusterName)));
        }
        StatusOr<XdsClusterConfig> xdsCluster =
            xdsConfig.getClusters().get(clusterName.substring("cluster:".length()));
        if (xdsCluster == null) {
          return new FailingClientCall<>(
              Status.UNAVAILABLE.withDescription(
                  String.format(
                      "GCP Authn for %s with %s - xds cluster config does not contain xds cluster",
                      filterInstanceName, clusterName)));
        }
        if (!xdsCluster.hasValue()) {
          return new FailingClientCall<>(xdsCluster.getStatus());
        }
        Object audienceObj =
            xdsCluster.getValue().getClusterResource().parsedMetadata().get(filterInstanceName);
        if (audienceObj == null) {
          return next.newCall(method, callOptions);
        }
        if (!(audienceObj instanceof AudienceWrapper)) {
          return new FailingClientCall<>(
              Status.UNAVAILABLE.withDescription(
                  String.format("GCP Authn found wrong type in %s metadata: %s=%s",
                      clusterName, filterInstanceName, audienceObj.getClass())));
        }
        AudienceWrapper audience = (AudienceWrapper) audienceObj;
        CallCredentials existingCallCredentials = callOptions.getCredentials();
        CallCredentials newCallCredentials =
            getCallCredentials(callCredentialsCache, audience.audience, credentials);
        if (existingCallCredentials != null) {
          callOptions = callOptions.withCallCredentials(
              new CompositeCallCredentials(existingCallCredentials, newCallCredentials));
        } else {
          callOptions = callOptions.withCallCredentials(newCallCredentials);
        }
        return next.newCall(method, callOptions);
      }
    };
  }

  private CallCredentials getCallCredentials(LruCache<String, CallCredentials> cache,
      String audience, ComputeEngineCredentials credentials) {

    synchronized (cache) {
      return cache.getOrInsert(audience, key -> {
        IdTokenCredentials creds = IdTokenCredentials.newBuilder()
            .setIdTokenProvider(credentials)
            .setTargetAudience(audience)
            .build();
        return MoreCallCredentials.from(creds);
      });
    }
  }

  static final class GcpAuthenticationConfig implements FilterConfig {

    private final int cacheSize;

    public GcpAuthenticationConfig(int cacheSize) {
      this.cacheSize = cacheSize;
    }

    public int getCacheSize() {
      return cacheSize;
    }

    @Override
    public String typeUrl() {
      return GcpAuthenticationFilter.TYPE_URL;
    }
  }

  /** An implementation of {@link ClientCall} that fails when started. */
  @VisibleForTesting
  static final class FailingClientCall<ReqT, RespT> extends ClientCall<ReqT, RespT> {

    @VisibleForTesting
    final Status error;

    public FailingClientCall(Status error) {
      this.error = error;
    }

    @Override
    public void start(ClientCall.Listener<RespT> listener, Metadata headers) {
      listener.onClose(error, new Metadata());
    }

    @Override
    public void request(int numMessages) {}

    @Override
    public void cancel(String message, Throwable cause) {}

    @Override
    public void halfClose() {}

    @Override
    public void sendMessage(ReqT message) {}
  }

  private static final class LruCache<K, V> {

    private Map<K, V> cache;
    private int maxSize;

    LruCache(int maxSize) {
      this.maxSize = maxSize;
      this.cache = createEvictingMap(maxSize);
    }

    V getOrInsert(K key, Function<K, V> create) {
      return cache.computeIfAbsent(key, create);
    }

    private void resizeCache(int newSize) {
      if (newSize >= maxSize) {
        maxSize = newSize;
        return;
      }
      Map<K, V> newCache = createEvictingMap(newSize);
      maxSize = newSize;
      newCache.putAll(cache);
      cache = newCache;
    }

    private Map<K, V> createEvictingMap(int size) {
      return new LinkedHashMap<K, V>(size, 0.75f, true) {
        @Override
        protected boolean removeEldestEntry(Map.Entry<K, V> eldest) {
          return size() > LruCache.this.maxSize;
        }
      };
    }
  }

  static class AudienceMetadataParser implements MetadataValueParser {

    static final class AudienceWrapper {
      final String audience;

      AudienceWrapper(String audience) {
        this.audience = checkNotNull(audience);
      }
    }

    @Override
    public String getTypeUrl() {
      return "type.googleapis.com/envoy.extensions.filters.http.gcp_authn.v3.Audience";
    }

    @Override
    public AudienceWrapper parse(Any any) throws ResourceInvalidException {
      Audience audience;
      try {
        audience = any.unpack(Audience.class);
      } catch (InvalidProtocolBufferException ex) {
        throw new ResourceInvalidException("Invalid Resource in address proto", ex);
      }
      String url = audience.getUrl();
      if (url.isEmpty()) {
        throw new ResourceInvalidException(
            "Audience URL is empty. Metadata value must contain a valid URL.");
      }
      return new AudienceWrapper(url);
    }
  }
}

1	/*
2	* Copyright 2021 The gRPC Authors
3	*
4	* Licensed under the Apache License, Version 2.0 (the "License");
5	* you may not use this file except in compliance with the License.
6	* You may obtain a copy of the License at
7	*
8	* http://www.apache.org/licenses/LICENSE-2.0
9	*
10	* Unless required by applicable law or agreed to in writing, software
11	* distributed under the License is distributed on an "AS IS" BASIS,
12	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13	* See the License for the specific language governing permissions and
14	* limitations under the License.
15	*/
16
17	package io.grpc.xds;
18
19	import static com.google.common.base.Preconditions.checkNotNull;
20	import static io.grpc.xds.XdsNameResolver.CLUSTER_SELECTION_KEY;
21	import static io.grpc.xds.XdsNameResolver.XDS_CONFIG_CALL_OPTION_KEY;
22
23	import com.google.auth.oauth2.ComputeEngineCredentials;
24	import com.google.auth.oauth2.IdTokenCredentials;
25	import com.google.common.annotations.VisibleForTesting;
26	import com.google.common.primitives.UnsignedLongs;
27	import com.google.protobuf.Any;
28	import com.google.protobuf.InvalidProtocolBufferException;
29	import com.google.protobuf.Message;
30	import io.envoyproxy.envoy.extensions.filters.http.gcp_authn.v3.Audience;
31	import io.envoyproxy.envoy.extensions.filters.http.gcp_authn.v3.GcpAuthnFilterConfig;
32	import io.envoyproxy.envoy.extensions.filters.http.gcp_authn.v3.TokenCacheConfig;
33	import io.grpc.CallCredentials;
34	import io.grpc.CallOptions;
35	import io.grpc.Channel;
36	import io.grpc.ClientCall;
37	import io.grpc.ClientInterceptor;
38	import io.grpc.CompositeCallCredentials;
39	import io.grpc.Metadata;
40	import io.grpc.MethodDescriptor;
41	import io.grpc.Status;
42	import io.grpc.StatusOr;
43	import io.grpc.auth.MoreCallCredentials;
44	import io.grpc.xds.GcpAuthenticationFilter.AudienceMetadataParser.AudienceWrapper;
45	import io.grpc.xds.MetadataRegistry.MetadataValueParser;
46	import io.grpc.xds.XdsConfig.XdsClusterConfig;
47	import io.grpc.xds.client.XdsResourceType.ResourceInvalidException;
48	import java.util.LinkedHashMap;
49	import java.util.Map;
50	import java.util.concurrent.ScheduledExecutorService;
51	import java.util.function.Function;
52	import javax.annotation.Nullable;
53
54	/**
55	* A {@link Filter} that injects a {@link CallCredentials} to handle
56	* authentication for xDS credentials.
57	*/
58	final class GcpAuthenticationFilter implements Filter {
59
60	static final String TYPE_URL =
61	"type.googleapis.com/envoy.extensions.filters.http.gcp_authn.v3.GcpAuthnFilterConfig";
62	private final LruCache<String, CallCredentials> callCredentialsCache;
63	final String filterInstanceName;
64
65	GcpAuthenticationFilter(String name, int cacheSize) {	1✔
66	filterInstanceName = checkNotNull(name, "name");	1✔
67	this.callCredentialsCache = new LruCache<>(cacheSize);	1✔
68	}	1✔
69
70	static final class Provider implements Filter.Provider {	1✔
71	private final int cacheSize = 10;	1✔
72
73	@Override
74	public String[] typeUrls() {
75	return new String[]{TYPE_URL};	×
76	}
77
78	@Override
79	public boolean isClientFilter() {
80	return true;	1✔
81	}
82
83	@Override
84	public GcpAuthenticationFilter newInstance(String name) {
85	return new GcpAuthenticationFilter(name, cacheSize);	×
86	}
87
88	@Override
89	public ConfigOrError<GcpAuthenticationConfig> parseFilterConfig(Message rawProtoMessage) {
90	GcpAuthnFilterConfig gcpAuthnProto;
91	if (!(rawProtoMessage instanceof Any)) {	1✔
92	return ConfigOrError.fromError("Invalid config type: " + rawProtoMessage.getClass());	1✔
93	}
94	Any anyMessage = (Any) rawProtoMessage;	1✔
95
96	try {
97	gcpAuthnProto = anyMessage.unpack(GcpAuthnFilterConfig.class);	1✔
98	} catch (InvalidProtocolBufferException e) {	×
99	return ConfigOrError.fromError("Invalid proto: " + e);	×
100	}	1✔
101
102	long cacheSize = 10;	1✔
103	// Validate cache_config
104	if (gcpAuthnProto.hasCacheConfig()) {	1✔
105	TokenCacheConfig cacheConfig = gcpAuthnProto.getCacheConfig();	1✔
106	if (cacheConfig.hasCacheSize()) {	1✔
107	cacheSize = cacheConfig.getCacheSize().getValue();	1✔
108	if (cacheSize == 0) {	1✔
109	return ConfigOrError.fromError(	1✔
110	"cache_config.cache_size must be greater than zero");
111	}
112	}
113
114	// LruCache's size is an int and briefly exceeds its maximum size before evicting entries
115	cacheSize = UnsignedLongs.min(cacheSize, Integer.MAX_VALUE - 1);	1✔
116	}
117
118	GcpAuthenticationConfig config = new GcpAuthenticationConfig((int) cacheSize);	1✔
119	return ConfigOrError.fromConfig(config);	1✔
120	}
121
122	@Override
123	public ConfigOrError<GcpAuthenticationConfig> parseFilterConfigOverride(
124	Message rawProtoMessage) {
125	return parseFilterConfig(rawProtoMessage);	×
126	}
127	}
128
129	@Nullable
130	@Override
131	public ClientInterceptor buildClientInterceptor(FilterConfig config,
132	@Nullable FilterConfig overrideConfig, ScheduledExecutorService scheduler) {
133
134	ComputeEngineCredentials credentials = ComputeEngineCredentials.create();	1✔
135	synchronized (callCredentialsCache) {	1✔
136	callCredentialsCache.resizeCache(((GcpAuthenticationConfig) config).getCacheSize());	1✔
137	}	1✔
138	return new ClientInterceptor() {	1✔
139	@Override
140	public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(
141	MethodDescriptor<ReqT, RespT> method, CallOptions callOptions, Channel next) {
142
143	String clusterName = callOptions.getOption(CLUSTER_SELECTION_KEY);	1✔
144	if (clusterName == null) {	1✔
145	return new FailingClientCall<>(	1✔
146	Status.UNAVAILABLE.withDescription(	1✔
147	String.format(	1✔
148	"GCP Authn for %s does not contain cluster resource", filterInstanceName)));
149	}
150
151	if (!clusterName.startsWith("cluster:")) {	1✔
152	return next.newCall(method, callOptions);	1✔
153	}
154	XdsConfig xdsConfig = callOptions.getOption(XDS_CONFIG_CALL_OPTION_KEY);	1✔
155	if (xdsConfig == null) {	1✔
156	return new FailingClientCall<>(	1✔
157	Status.UNAVAILABLE.withDescription(	1✔
158	String.format(	1✔
159	"GCP Authn for %s with %s does not contain xds configuration",
160	filterInstanceName, clusterName)));
161	}
162	StatusOr<XdsClusterConfig> xdsCluster =	1✔
163	xdsConfig.getClusters().get(clusterName.substring("cluster:".length()));	1✔
164	if (xdsCluster == null) {	1✔
165	return new FailingClientCall<>(	1✔
166	Status.UNAVAILABLE.withDescription(	1✔
167	String.format(	1✔
168	"GCP Authn for %s with %s - xds cluster config does not contain xds cluster",
169	filterInstanceName, clusterName)));
170	}
171	if (!xdsCluster.hasValue()) {	1✔
172	return new FailingClientCall<>(xdsCluster.getStatus());	1✔
173	}
174	Object audienceObj =	1✔
175	xdsCluster.getValue().getClusterResource().parsedMetadata().get(filterInstanceName);	1✔
176	if (audienceObj == null) {	1✔
177	return next.newCall(method, callOptions);	×
178	}
179	if (!(audienceObj instanceof AudienceWrapper)) {	1✔
180	return new FailingClientCall<>(	1✔
181	Status.UNAVAILABLE.withDescription(	1✔
182	String.format("GCP Authn found wrong type in %s metadata: %s=%s",	1✔
183	clusterName, filterInstanceName, audienceObj.getClass())));	1✔
184	}
185	AudienceWrapper audience = (AudienceWrapper) audienceObj;	1✔
186	CallCredentials existingCallCredentials = callOptions.getCredentials();	1✔
187	CallCredentials newCallCredentials =	1✔
188	getCallCredentials(callCredentialsCache, audience.audience, credentials);	1✔
189	if (existingCallCredentials != null) {	1✔
190	callOptions = callOptions.withCallCredentials(	×
191	new CompositeCallCredentials(existingCallCredentials, newCallCredentials));
192	} else {
193	callOptions = callOptions.withCallCredentials(newCallCredentials);	1✔
194	}
195	return next.newCall(method, callOptions);	1✔
196	}
197	};
198	}
199
200	private CallCredentials getCallCredentials(LruCache<String, CallCredentials> cache,
201	String audience, ComputeEngineCredentials credentials) {
202
203	synchronized (cache) {	1✔
204	return cache.getOrInsert(audience, key -> {	1✔
205	IdTokenCredentials creds = IdTokenCredentials.newBuilder()	1✔
206	.setIdTokenProvider(credentials)	1✔
207	.setTargetAudience(audience)	1✔
208	.build();	1✔
209	return MoreCallCredentials.from(creds);	1✔
210	});
211	}
212	}
213
214	static final class GcpAuthenticationConfig implements FilterConfig {
215
216	private final int cacheSize;
217
218	public GcpAuthenticationConfig(int cacheSize) {	1✔
219	this.cacheSize = cacheSize;	1✔
220	}	1✔
221
222	public int getCacheSize() {
223	return cacheSize;	1✔
224	}
225
226	@Override
227	public String typeUrl() {
228	return GcpAuthenticationFilter.TYPE_URL;	×
229	}
230	}
231
232	/** An implementation of {@link ClientCall} that fails when started. */
233	@VisibleForTesting
234	static final class FailingClientCall<ReqT, RespT> extends ClientCall<ReqT, RespT> {
235
236	@VisibleForTesting
237	final Status error;
238
239	public FailingClientCall(Status error) {	1✔
240	this.error = error;	1✔
241	}	1✔
242
243	@Override
244	public void start(ClientCall.Listener<RespT> listener, Metadata headers) {
245	listener.onClose(error, new Metadata());	×
246	}	×
247
248	@Override
249	public void request(int numMessages) {}	×
250
251	@Override
252	public void cancel(String message, Throwable cause) {}	×
253
254	@Override
255	public void halfClose() {}	×
256
257	@Override
258	public void sendMessage(ReqT message) {}	×
259	}
260
261	private static final class LruCache<K, V> {
262
263	private Map<K, V> cache;
264	private int maxSize;
265
266	LruCache(int maxSize) {	1✔
267	this.maxSize = maxSize;	1✔
268	this.cache = createEvictingMap(maxSize);	1✔
269	}	1✔
270
271	V getOrInsert(K key, Function<K, V> create) {
272	return cache.computeIfAbsent(key, create);	1✔
273	}
274
275	private void resizeCache(int newSize) {
276	if (newSize >= maxSize) {	1✔
277	maxSize = newSize;	1✔
278	return;	1✔
279	}
280	Map<K, V> newCache = createEvictingMap(newSize);	1✔
281	maxSize = newSize;	1✔
282	newCache.putAll(cache);	1✔
283	cache = newCache;	1✔
284	}	1✔
285
286	private Map<K, V> createEvictingMap(int size) {
287	return new LinkedHashMap<K, V>(size, 0.75f, true) {	1✔
288	@Override
289	protected boolean removeEldestEntry(Map.Entry<K, V> eldest) {
290	return size() > LruCache.this.maxSize;	1✔
291	}
292	};
293	}
294	}
295
296	static class AudienceMetadataParser implements MetadataValueParser {	1✔
297
298	static final class AudienceWrapper {
299	final String audience;
300
301	AudienceWrapper(String audience) {	1✔
302	this.audience = checkNotNull(audience);	1✔
303	}	1✔
304	}
305
306	@Override
307	public String getTypeUrl() {
308	return "type.googleapis.com/envoy.extensions.filters.http.gcp_authn.v3.Audience";	1✔
309	}
310
311	@Override
312	public AudienceWrapper parse(Any any) throws ResourceInvalidException {
313	Audience audience;
314	try {
315	audience = any.unpack(Audience.class);	1✔
316	} catch (InvalidProtocolBufferException ex) {	×
317	throw new ResourceInvalidException("Invalid Resource in address proto", ex);	×
318	}	1✔
319	String url = audience.getUrl();	1✔
320	if (url.isEmpty()) {	1✔
321	throw new ResourceInvalidException(	×
322	"Audience URL is empty. Metadata value must contain a valid URL.");
323	}
324	return new AudienceWrapper(url);	1✔
325	}
326	}
327	}

grpc / grpc-java / #19824

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