[inference]predictor add GetInputType interface (#45143)

* predictor add GetInputType interface

* predictor change GetInputType to GetInputTypes

* predictor add tester

* predictor add tester

* predictor change GetInputType to GetInputTypes

* predictor change GetInputType to GetInputTypes

* predictor add tester

paddle/fluid/inference/api/analysis_predictor.cc

@@ -1454,6 +1454,37 @@ AnalysisPredictor::GetInputTensorShape() {
   return input_shapes;
 }
 
+std::map<std::string, paddle_infer::DataType>
+AnalysisPredictor::GetInputTypes() {
+  std::map<std::string, paddle_infer::DataType> input_type;
+  std::vector<std::string> names = GetInputNames();
+  for (const auto &name : names) {
+    auto *var = inference_program_->Block(0).FindVar(name);
+    PADDLE_ENFORCE_NOT_NULL(
+        var,
+        platform::errors::PreconditionNotMet(
+            "Input %s does not exist inference_program_.", name));
+    auto dtype = var->GetDataType();
+    if (dtype == paddle::framework::proto::VarType::FP32) {
+      input_type[name] = paddle_infer::DataType::FLOAT32;
+    } else if (dtype == paddle::framework::proto::VarType::FP16) {
+      input_type[name] = paddle_infer::DataType::FLOAT16;
+    } else if (dtype == paddle::framework::proto::VarType::INT64) {
+      input_type[name] = paddle_infer::DataType::INT64;
+    } else if (dtype == paddle::framework::proto::VarType::INT32) {
+      input_type[name] = paddle_infer::DataType::INT32;
+    } else if (dtype == paddle::framework::proto::VarType::UINT8) {
+      input_type[name] = paddle_infer::DataType::UINT8;
+    } else if (dtype == paddle::framework::proto::VarType::INT8) {
+      input_type[name] = paddle_infer::DataType::INT8;
+    } else {
+      PADDLE_THROW(paddle::platform::errors::Unimplemented(
+          "Unsupported data type `%s` when get input dtype ", dtype));
+    }
+  }
+  return input_type;
+}
+
 std::vector<std::string> AnalysisPredictor::GetOutputNames() {
   std::vector<std::string> output_names;
   for (auto &item : idx2fetches_) {
@@ -2172,6 +2203,10 @@ std::vector<std::string> Predictor::GetInputNames() {
   return predictor_->GetInputNames();
 }
 
+std::map<std::string, DataType> Predictor::GetInputTypes() {
+  return predictor_->GetInputTypes();
+}
+
 std::unique_ptr<Tensor> Predictor::GetInputHandle(const std::string &name) {
   return predictor_->GetInputTensor(name);
 }

paddle/fluid/inference/api/analysis_predictor.h

@@ -173,6 +173,12 @@ class AnalysisPredictor : public PaddlePredictor {
   /// \return the map of input names and shapes
   ///
   std::map<std::string, std::vector<int64_t>> GetInputTensorShape() override;
+  ///
+  /// \brief Get all input names and their corresponding type
+  ///
+  /// \return the map of input names and type
+  ///
+  std::map<std::string, paddle_infer::DataType> GetInputTypes() override;
 
   ///
   /// \brief Run the prediction engine

paddle/fluid/inference/api/analysis_predictor_tester.cc

@@ -105,6 +105,7 @@ TEST(AnalysisPredictor, analysis_on) {
   ASSERT_TRUE(predictor->sub_scope_);
   ASSERT_EQ(predictor->scope_->parent(), nullptr);
   ASSERT_EQ(predictor->sub_scope_->parent(), predictor->scope_.get());
+  ASSERT_EQ(predictor->GetInputTypes().size(), 4UL);
   // 2. Dummy Input Data
   int64_t data[4] = {1, 2, 3, 4};
   PaddleTensor tensor;
@@ -389,6 +390,7 @@ TEST(Predictor, Run) {
   config.SetModel(FLAGS_dirname);
 
   auto predictor = CreatePredictor(config);
+  ASSERT_EQ(predictor->GetInputTypes().size(), 4UL);
 
   auto w0 = predictor->GetInputHandle("firstw");
   auto w1 = predictor->GetInputHandle("secondw");

paddle/fluid/inference/api/paddle_api.h

@@ -231,6 +231,12 @@ class PD_INFER_DECL PaddlePredictor {
     return {};
   }
 
+  /// \brief Get the input type of the model.
+  /// \return A map contains all the input names and type defined in the model.
+  virtual std::map<std::string, paddle_infer::DataType> GetInputTypes() {
+    return {};
+  }
+
   /// \brief Used to get the name of the network output.
   /// Be inherited by AnalysisPredictor, Only used in ZeroCopy scenarios.
   /// \return Output tensor names.

paddle/fluid/inference/api/paddle_inference_api.h

@@ -93,6 +93,13 @@ class PD_INFER_DECL Predictor {
   ///
   explicit Predictor(const Config& config);
 
+  ///
+  /// \brief Get all input names and their corresponding type
+  ///
+  /// \return the map of input names and type
+  ///
+  std::map<std::string, DataType> GetInputTypes();
+
   ///
   /// \brief Get the input names
   ///