Class NodeBuilder

tensorflow/core/graph/node_builder.h:42–155

This is a helper for creating a Node and adding it to a Graph. Internally, it uses a NodeDefBuilder to automatically set attrs that can be inferred from the inputs, and use default values (where they exist) for unspecified attrs. Example usage: Node* node; Status status = NodeBuilder(node_name, op_name) .Input(...) .Attr(...) .Finalize(&graph, &node); if (!status.ok()) return status; // Use node

//  if (!status.ok()) return status;
//  // Use node here.
class NodeBuilder {
 public:
  // For specifying the output of a Node to provide to one of the Input()
  // functions below.  It supports both regular inputs (where you are
  // connecting to an existing Node*), and inputs from outside the graph
  // (or haven't been added to the graph yet, like back edges, where
  // you don't have a Node*). Both types can be mixed, e.g. in an
  // ArraySlice.
  struct NodeOut {
    // For referencing an existing Node.
    NodeOut(Node* n, int32 i = 0);
    NodeOut(OutputTensor t);

    // For referencing Nodes not in the graph being built. It is
    // useful when preparing a graph for ExtendSession or creating a
    // back edge to a node that hasn't been added to the graph yet,
    // but will be.
    NodeOut(StringPiece name, int32 i, DataType t);

    // Default constructor for std::vector<NodeOut>.
    NodeOut();

    Node* node;
    // error is set to true if:
    // * the NodeOut was default constructed and never overwritten,
    // * a nullptr Node* was passed to the NodeOut constructor, or
    // * an out-of-range index was passed to the NodeOut constructor.
    bool error;
    string name;
    int32 index;
    DataType dt;
  };

  // Specify the name and the Op (either via an OpDef or the name of
  // the Op plus a registry) for the Node.  Other fields are
  // specified by calling the methods below.
  // REQUIRES: The OpDef must satisfy ValidateOpDef().
  NodeBuilder(StringPiece name, StringPiece op_name,
              const OpRegistryInterface* op_registry = OpRegistry::Global(),
              const NodeDebugInfo* debug = nullptr);
  NodeBuilder(StringPiece name, const OpDef* op_def);

  // Create a NodeBuilder from an existing NodeDefBuilder.
  NodeBuilder(const NodeDefBuilder& def_builder);

  // You must call one Input() function per input_arg in the Op,
  // *and in the same order as the input_args appear in the OpDef.*

  // For inputs that take a single tensor.
  NodeBuilder& Input(Node* src_node, int src_index = 0);
  NodeBuilder& Input(NodeOut src);

  // For inputs that take a list of tensors.
  NodeBuilder& Input(gtl::ArraySlice<NodeOut> src_list);

  // Require that this node run after src_node(s).
  NodeBuilder& ControlInput(Node* src_node);
  NodeBuilder& ControlInputs(gtl::ArraySlice<Node*> src_nodes);