xref: /aosp_15_r20/external/federated-compute/fcp/aggregation/core/tensor_aggregator.h (revision 14675a029014e728ec732f129a32e299b2da0601)
1 /*
2  * Copyright 2022 Google LLC
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 #ifndef FCP_AGGREGATION_CORE_TENSOR_AGGREGATOR_H_
18 #define FCP_AGGREGATION_CORE_TENSOR_AGGREGATOR_H_
19 
20 #include <vector>
21 
22 #include "fcp/aggregation/core/aggregator.h"
23 #include "fcp/aggregation/core/input_tensor_list.h"
24 #include "fcp/aggregation/core/tensor.h"
25 #include "fcp/base/monitoring.h"
26 
27 namespace fcp {
28 namespace aggregation {
29 
30 using OutputTensorList = std::vector<Tensor>;
31 
32 // TensorAggregator is a base class for implementing Aggregation intrinsics
33 // with Tensor being an input and output type for the aggregation.
34 class TensorAggregator
35     : public Aggregator<InputTensorList, OutputTensorList, TensorAggregator> {
36  public:
37   ~TensorAggregator() override = default;
38 
39   // Implementation of the base Aggregator class methods.
40   Status Accumulate(InputTensorList tensors) override;
41   bool CanReport() const override;
42   StatusOr<OutputTensorList> Report() && override;
43 
44   // Returns the number of aggregated inputs.
45   virtual int GetNumInputs() const = 0;
46 
47  protected:
48   // Construct TensorAggregator
TensorAggregator()49   explicit TensorAggregator() {}
50 
51   // The actual implementation of the tensor aggregation to be provided by
52   // a derived class.
53   virtual Status AggregateTensors(InputTensorList tensors) = 0;
54 
55   // Checks if the current TensorAggregator is valid e.g. the resulting output
56   // hasn't been consumed.
57   virtual Status CheckValid() const = 0;
58 
59   // Consumes the output of this TensorAggregator.
60   virtual OutputTensorList TakeOutputs() && = 0;
61 
62  private:
63   // Extracts the aggregated tensor and makes the current aggregator "consumed".
64   OutputTensorList TakeTensors() &&;
65 };
66 
67 }  // namespace aggregation
68 }  // namespace fcp
69 
70 #endif  // FCP_AGGREGATION_CORE_TENSOR_AGGREGATOR_H_
71