google.golang.org/grpc@v1.72.2/xds/internal/clients/xdsclient/resource_watcher.go (about)

     1  /*
     2   *
     3   * Copyright 2025 gRPC authors.
     4   *
     5   * Licensed under the Apache License, Version 2.0 (the "License");
     6   * you may not use this file except in compliance with the License.
     7   * You may obtain a copy of the License at
     8   *
     9   *     http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   *
    17   */
    18  
    19  package xdsclient
    20  
    21  // ResourceWatcher is notified of the resource updates and errors that are
    22  // received by the xDS client from the management server.
    23  //
    24  // All methods contain a done parameter which should be called when processing
    25  // of the update has completed.  For example, if processing a resource requires
    26  // watching new resources, those watches should be completed before done is
    27  // called, which can happen after the ResourceWatcher method has returned.
    28  // Failure to call done will prevent the xDS client from providing future
    29  // ResourceWatcher notifications.
    30  type ResourceWatcher interface {
    31  	// ResourceChanged indicates a new version of the resource is available.
    32  	ResourceChanged(resourceData ResourceData, done func())
    33  
    34  	// ResourceError indicates an error occurred while trying to fetch or
    35  	// decode the associated resource. The previous version of the resource
    36  	// should be considered invalid.
    37  	ResourceError(err error, done func())
    38  
    39  	// AmbientError indicates an error occurred after a resource has been
    40  	// received that should not modify the use of that resource but may provide
    41  	// useful information about the state of the XDSClient for debugging
    42  	// purposes. The previous version of the resource should still be
    43  	// considered valid.
    44  	AmbientError(err error, done func())
    45  }