gitee.com/ks-custle/core-gm@v0.0.0-20230922171213-b83bdd97b62c/go-control-plane/pkg/cache/v3/mux.go (about)

     1  // Copyright 2020 Envoyproxy Authors
     2  //
     3  //   Licensed under the Apache License, Version 2.0 (the "License");
     4  //   you may not use this file except in compliance with the License.
     5  //   You may obtain a copy of the License at
     6  //
     7  //       http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  //   Unless required by applicable law or agreed to in writing, software
    10  //   distributed under the License is distributed on an "AS IS" BASIS,
    11  //   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  //   See the License for the specific language governing permissions and
    13  //   limitations under the License.
    14  
    15  package cache
    16  
    17  import (
    18  	"context"
    19  	"errors"
    20  	"gitee.com/ks-custle/core-gm/go-control-plane/pkg/server/stream/v3"
    21  )
    22  
    23  // MuxCache multiplexes across several caches using a classification function.
    24  // If there is no matching cache for a classification result, the cache
    25  // responds with an empty closed channel, which effectively terminates the
    26  // stream on the server. It might be preferred to respond with a "nil" channel
    27  // instead which will leave the stream open in case the stream is aggregated by
    28  // making sure there is always a matching cache.
    29  type MuxCache struct {
    30  	// Classification functions.
    31  	Classify      func(*Request) string
    32  	ClassifyDelta func(*DeltaRequest) string
    33  	// Muxed caches.
    34  	Caches map[string]Cache
    35  }
    36  
    37  var _ Cache = &MuxCache{}
    38  
    39  func (mux *MuxCache) CreateWatch(request *Request, value chan Response) func() {
    40  	key := mux.Classify(request)
    41  	cache, exists := mux.Caches[key]
    42  	if !exists {
    43  		value <- nil
    44  		return nil
    45  	}
    46  	return cache.CreateWatch(request, value)
    47  }
    48  
    49  func (mux *MuxCache) CreateDeltaWatch(request *DeltaRequest, state stream.StreamState, value chan DeltaResponse) func() {
    50  	key := mux.ClassifyDelta(request)
    51  	cache, exists := mux.Caches[key]
    52  	if !exists {
    53  		value <- nil
    54  		return nil
    55  	}
    56  	return cache.CreateDeltaWatch(request, state, value)
    57  }
    58  
    59  //goland:noinspection GoUnusedParameter
    60  func (mux *MuxCache) Fetch(ctx context.Context, request *Request) (Response, error) {
    61  	return nil, errors.New("not implemented")
    62  }