| // Copyright 2020 Google LLC |
| // |
| // 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 |
| // |
| // https://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. |
| // |
| |
| #ifndef NLP_SAFT_COMPONENTS_LANG_ID_MOBILE_FB_MODEL_MODEL_PROVIDER_FROM_FB_H_ |
| #define NLP_SAFT_COMPONENTS_LANG_ID_MOBILE_FB_MODEL_MODEL_PROVIDER_FROM_FB_H_ |
| |
| #include <cstddef> |
| #include <memory> |
| #include <string> |
| #include <vector> |
| |
| #include "lang_id/common/fel/task-context.h" |
| #include "lang_id/common/file/mmap.h" |
| #include "lang_id/common/flatbuffers/model_generated.h" |
| #include "lang_id/common/lite_strings/stringpiece.h" |
| #include "lang_id/model-provider.h" |
| |
| namespace libtextclassifier3 { |
| namespace mobile { |
| namespace lang_id { |
| |
| // ModelProvider for LangId, based on a SAFT model in flatbuffer format. |
| class ModelProviderFromFlatbuffer : public ModelProvider { |
| public: |
| // Constructs a model provider based on a flatbuffer-format SAFT model from |
| // |filename|. |
| explicit ModelProviderFromFlatbuffer(const std::string &filename); |
| |
| // Constructs a model provider based on a flatbuffer-format SAFT model from |
| // file descriptor |fd|. |
| explicit ModelProviderFromFlatbuffer(FileDescriptorOrHandle fd); |
| |
| // Constructs a model provider from a flatbuffer-format SAFT model the bytes |
| // of which are already in RAM (size bytes starting from address data). |
| // Useful if you "transport" these bytes otherwise than via a normal file |
| // (e.g., if you embed them somehow in your binary). |
| // |
| // IMPORTANT: |data| should be alive during the lifetime of the |
| // newly-constructed ModelProviderFromFlatbuffer. This is trivial to ensure |
| // for data that's statically embedded in your binary, but more complex in |
| // other cases. To avoid overhead (e.g., heap allocation), this method does |
| // not make a private copy of the data. In general, the ownership of the |
| // newly-constructed ModelProviderFromFlatbuffer is immediately passed to a |
| // LangId object (which doesn't pass it further); hence, one needs to make |
| // sure |data| is alive during the lifetime of that LangId object. |
| ModelProviderFromFlatbuffer(const char *data, std::size_t size) { |
| StringPiece model_bytes(data, size); |
| Initialize(model_bytes); |
| } |
| |
| ~ModelProviderFromFlatbuffer() override = default; |
| |
| const TaskContext *GetTaskContext() const override { |
| return &context_; |
| } |
| |
| const EmbeddingNetworkParams *GetNnParams() const override { |
| return nn_params_.get(); |
| } |
| |
| std::vector<std::string> GetLanguages() const override { return languages_; } |
| |
| private: |
| // Initializes the fields of this class based on the flatbuffer from |
| // |model_bytes|. These bytes are supposed to be the representation of a |
| // Model flatbuffer and should be alive during the lifetime of this object. |
| void Initialize(StringPiece model_bytes); |
| |
| // Initializes nn_params_ based on model_. |
| bool InitNetworkParams(); |
| |
| // If filename-based constructor is used, scoped_mmap_ keeps the file mmapped |
| // during the lifetime of this object, such that references inside the Model |
| // flatbuffer from those bytes remain valid. |
| const std::unique_ptr<ScopedMmap> scoped_mmap_; |
| |
| // Pointer to the flatbuffer from |
| // |
| // (a) [if filename constructor was used:] the bytes mmapped by scoped_mmap_ |
| // (for safety considerations, see comment for that field), or |
| // |
| // (b) [of (data, size) constructor was used:] the bytes from [data, |
| // data+size). Please read carefully the doc for that constructor. |
| const saft_fbs::Model *model_; |
| |
| // Context returned by this model provider. We set its parameters based on |
| // model_, at construction time. |
| TaskContext context_; |
| |
| // List of supported languages, see GetLanguages(). We expect this list to be |
| // specified by the ModelParameter named "supported_languages" from model_. |
| std::vector<std::string> languages_; |
| |
| // EmbeddingNetworkParams, see GetNnParams(). Set based on the ModelInput |
| // named "language-identifier-network" from model_. |
| std::unique_ptr<EmbeddingNetworkParams> nn_params_; |
| }; |
| |
| } // namespace lang_id |
| } // namespace mobile |
| } // namespace nlp_saft |
| |
| #endif // NLP_SAFT_COMPONENTS_LANG_ID_MOBILE_FB_MODEL_MODEL_PROVIDER_FROM_FB_H_ |