Port FlatBuffers to Python.

Implement code generation and self-contained runtime library for Python. The test suite verifies: - Correctness of generated Python code by comparing output to that of the other language ports. - The exact bytes in the Builder buffer during many scenarios. - Vtable deduplication correctness. - Edge cases for table construction, via a fuzzer derived from the Go implementation. - All code is simultaneously valid in Python 2.6, 2.7, and 3.4. The test suite includes benchmarks for: - Building 'gold' data. - Parsing 'gold' data. - Deduplicating vtables. All tests pass on this author's system for the following Python implementations: - CPython 2.6.7 - CPython 2.7.8 - CPython 3.4.2 - PyPy 2.5.0 (CPython 2.7.8 compatible)
2026-06-02 20:15:34 +00:00 · 2014-12-16 00:32:11 -08:00
parent 4d213c2d06
commit 48dfc69ee6
35 changed files with 3608 additions and 35 deletions
--- a/src/idl_gen_python.cpp
+++ b/src/idl_gen_python.cpp
@@ -0,0 +1,664 @@
+/*
+ * Copyright 2014 Google Inc. All rights reserved.
+ *
+ * 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
+ *
+ *     http://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.
+ */
+
+// independent from idl_parser, since this code is not needed for most clients
+
+#include <string>
+
+#include "flatbuffers/flatbuffers.h"
+#include "flatbuffers/idl.h"
+#include "flatbuffers/util.h"
+
+namespace flatbuffers {
+namespace python {
+
+static std::string GenGetter(const Type &type);
+static std::string GenMethod(const FieldDef &field);
+static void GenStructBuilder(const StructDef &struct_def,
+                             std::string *code_ptr);
+static void GenReceiver(const StructDef &struct_def, std::string *code_ptr);
+static std::string GenTypeBasic(const Type &type);
+static std::string GenTypeGet(const Type &type);
+static std::string TypeName(const FieldDef &field);
+
+
+// Hardcode spaces per indentation.
+const std::string Indent = "    ";
+
+// Most field accessors need to retrieve and test the field offset first,
+// this is the prefix code for that.
+std::string OffsetPrefix(const FieldDef &field) {
+  return "\n" + Indent + Indent +
+         "o = flatbuffers.number_types.UOffsetTFlags.py_type" +
+         "(self._tab.Offset(" +
+         NumToString(field.value.offset) +
+         "))\n" + Indent + Indent + "if o != 0:\n";
+}
+
+// Begin by declaring namespace and imports.
+static void BeginFile(const std::string name_space_name,
+                      const bool needs_imports,
+                      std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += "# automatically generated, do not modify\n\n";
+  code += "# namespace: " + name_space_name + "\n\n";
+  if (needs_imports) {
+    code += "import flatbuffers\n\n";
+  }
+}
+
+// Begin a class declaration.
+static void BeginClass(const StructDef &struct_def, std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += "class " + struct_def.name + "(object):\n";
+  code += Indent + "__slots__ = ['_tab']";
+  code += "\n\n";
+}
+
+// Begin enum code with a class declaration.
+static void BeginEnum(const std::string class_name, std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += "class " + class_name + "(object):\n";
+}
+
+// A single enum member.
+static void EnumMember(const EnumVal ev, std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += Indent;
+  code += ev.name;
+  code += " = ";
+  code += NumToString(ev.value) + "\n";
+}
+
+// End enum code.
+static void EndEnum(std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += "\n";
+}
+
+// Initialize a new struct or table from existing data.
+static void NewRootTypeFromBuffer(const StructDef &struct_def,
+                                  std::string *code_ptr) {
+  std::string &code = *code_ptr;
+
+  code += Indent + "@classmethod\n";
+  code += Indent + "def GetRootAs";
+  code += struct_def.name;
+  code += "(cls, buf, offset):";
+  code += "\n";
+  code += Indent + Indent;
+  code += "n = flatbuffers.encode.Get";
+  code += "(flatbuffers.packer.uoffset, buf, offset)\n";
+  code += Indent + Indent + "x = " + struct_def.name + "()\n";
+  code += Indent + Indent + "x.Init(buf, n + offset)\n";
+  code += Indent + Indent + "return x\n";
+  code += "\n\n";
+}
+
+// Initialize an existing object with other data, to avoid an allocation.
+static void InitializeExisting(const StructDef &struct_def,
+                               std::string *code_ptr) {
+  std::string &code = *code_ptr;
+
+  GenReceiver(struct_def, code_ptr);
+  code += "Init(self, buf, pos):\n";
+  code += Indent + Indent + "self._tab = flatbuffers.table.Table(buf, pos)\n";
+  code += "\n";
+}
+
+// Get the length of a vector.
+static void GetVectorLen(const StructDef &struct_def,
+                         const FieldDef &field,
+                         std::string *code_ptr) {
+  std::string &code = *code_ptr;
+
+  GenReceiver(struct_def, code_ptr);
+  code += MakeCamel(field.name) + "Length(self";
+  code += "):" + OffsetPrefix(field);
+  code += Indent + Indent + Indent + "return self._tab.VectorLen(o)\n";
+  code += Indent + Indent + "return 0\n\n";
+}
+
+// Get the value of a struct's scalar.
+static void GetScalarFieldOfStruct(const StructDef &struct_def,
+                                   const FieldDef &field,
+                                   std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  std::string getter = GenGetter(field.value.type);
+  GenReceiver(struct_def, code_ptr);
+  code += MakeCamel(field.name);
+  code += "(self): return " + getter;
+  code += "self._tab.Pos + flatbuffers.number_types.UOffsetTFlags.py_type(";
+  code += NumToString(field.value.offset) + "))\n";
+}
+
+// Get the value of a table's scalar.
+static void GetScalarFieldOfTable(const StructDef &struct_def,
+                                  const FieldDef &field,
+                                  std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  std::string getter = GenGetter(field.value.type);
+  GenReceiver(struct_def, code_ptr);
+  code += MakeCamel(field.name);
+  code += "(self):";
+  code += OffsetPrefix(field);
+  code += Indent + Indent + Indent + "return " + getter;
+  code += "o + self._tab.Pos)\n";
+  code += Indent + Indent + "return " + field.value.constant + "\n\n";
+}
+
+// Get a struct by initializing an existing struct.
+// Specific to Struct.
+static void GetStructFieldOfStruct(const StructDef &struct_def,
+                                   const FieldDef &field,
+                                   std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  GenReceiver(struct_def, code_ptr);
+  code += MakeCamel(field.name);
+  code += "(self, obj):\n";
+  code += Indent + Indent + "obj.Init(self._tab.Bytes, self._tab.Pos + ";
+  code += NumToString(field.value.offset) + ")";
+  code += "\n" + Indent + Indent + "return obj\n\n";
+}
+
+// Get a struct by initializing an existing struct.
+// Specific to Table.
+static void GetStructFieldOfTable(const StructDef &struct_def,
+                                  const FieldDef &field,
+                                  std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  GenReceiver(struct_def, code_ptr);
+  code += MakeCamel(field.name);
+  code += "(self):";
+  code += OffsetPrefix(field);
+  if (field.value.type.struct_def->fixed) {
+    code += Indent + Indent + Indent + "x = o + self._tab.Pos\n";
+  } else {
+    code += Indent + Indent + Indent;
+    code += "x = self._tab.Indirect(o + self._tab.Pos)\n";
+  }
+  code += Indent + Indent + Indent;
+  code += "from ." + TypeName(field) + " import " + TypeName(field) + "\n";
+  code += Indent + Indent + Indent + "obj = " + TypeName(field) + "()\n";
+  code += Indent + Indent + Indent + "obj.Init(self._tab.Bytes, x)\n";
+  code += Indent + Indent + Indent + "return obj\n";
+  code += Indent + Indent + "return None\n\n";
+}
+
+// Get the value of a string.
+static void GetStringField(const StructDef &struct_def,
+                           const FieldDef &field,
+                           std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  GenReceiver(struct_def, code_ptr);
+  code += MakeCamel(field.name);
+  code += "(self):";
+  code += OffsetPrefix(field);
+  code += Indent + Indent + Indent + "return " + GenGetter(field.value.type);
+  code += "o + self._tab.Pos)\n";
+  code += Indent + Indent + "return \"\"\n\n";
+}
+
+// Get the value of a union from an object.
+static void GetUnionField(const StructDef &struct_def,
+                          const FieldDef &field,
+                          std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  GenReceiver(struct_def, code_ptr);
+  code += MakeCamel(field.name) + "(self):";
+  code += OffsetPrefix(field);
+
+  // TODO(rw): this works and is not the good way to it:
+  bool is_native_table = TypeName(field) == "*flatbuffers.Table";
+  if (is_native_table) {
+    code += Indent + Indent + Indent + "from flatbuffers.table import Table\n";
+  } else {
+    code += Indent + Indent + Indent;
+    code += "from ." + TypeName(field) + " import " + TypeName(field) + "\n";
+  }
+  code += Indent + Indent + Indent + "obj = Table(bytearray(), 0)\n";
+  code += Indent + Indent + Indent + GenGetter(field.value.type);
+  code += "obj, o)\n" + Indent + Indent + Indent + "return obj\n";
+  code += Indent + Indent + "return None\n\n";
+}
+
+// Get the value of a vector's struct member.
+static void GetMemberOfVectorOfStruct(const StructDef &struct_def,
+                                      const FieldDef &field,
+                                      std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  auto vectortype = field.value.type.VectorType();
+
+  GenReceiver(struct_def, code_ptr);
+  code += MakeCamel(field.name);
+  code += "(self, j):" + OffsetPrefix(field);
+  code += Indent + Indent + Indent + "x = self._tab.Vector(o)\n";
+  code += Indent + Indent + Indent;
+  code += "x += flatbuffers.number_types.UOffsetTFlags.py_type(j) * ";
+  code += NumToString(InlineSize(vectortype)) + "\n";
+  if (!(vectortype.struct_def->fixed)) {
+    code += Indent + Indent + Indent + "x = self._tab.Indirect(x)\n";
+  }
+  code += Indent + Indent + Indent;
+  code += "from ." + TypeName(field) + " import " + TypeName(field) + "\n";
+  code += Indent + Indent + Indent + "obj = " + TypeName(field) + "()\n";
+  code += Indent + Indent + Indent + "obj.Init(self._tab.Bytes, x)\n";
+  code += Indent + Indent + Indent + "return obj\n";
+  code += Indent + Indent + "return None\n\n";
+}
+
+// Get the value of a vector's non-struct member. Uses a named return
+// argument to conveniently set the zero value for the result.
+static void GetMemberOfVectorOfNonStruct(const StructDef &struct_def,
+                                         const FieldDef &field,
+                                         std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  auto vectortype = field.value.type.VectorType();
+
+  GenReceiver(struct_def, code_ptr);
+  code += MakeCamel(field.name);
+  code += "(self, j):";
+  code += OffsetPrefix(field);
+  code += Indent + Indent + Indent + "a = self._tab.Vector(o)\n";
+  code += Indent + Indent + Indent;
+  code += "return " + GenGetter(field.value.type);
+  code += "a + flatbuffers.number_types.UOffsetTFlags.py_type(j * ";
+  code += NumToString(InlineSize(vectortype)) + "))\n";
+  if (vectortype.base_type == BASE_TYPE_STRING) {
+    code += Indent + Indent + "return \"\"\n";
+  } else {
+    code += Indent + Indent + "return 0\n";
+  }
+  code += "\n";
+}
+
+// Begin the creator function signature.
+static void BeginBuilderArgs(const StructDef &struct_def,
+                             std::string *code_ptr) {
+  std::string &code = *code_ptr;
+
+  code += "\n";
+  code += "def Create" + struct_def.name;
+  code += "(builder";
+}
+
+// Recursively generate arguments for a constructor, to deal with nested
+// structs.
+static void StructBuilderArgs(const StructDef &struct_def,
+                              const char *nameprefix,
+                              std::string *code_ptr) {
+  for (auto it = struct_def.fields.vec.begin();
+       it != struct_def.fields.vec.end();
+       ++it) {
+    auto &field = **it;
+    if (IsStruct(field.value.type)) {
+      // Generate arguments for a struct inside a struct. To ensure names
+      // don't clash, and to make it obvious these arguments are constructing
+      // a nested struct, prefix the name with the struct name.
+      StructBuilderArgs(*field.value.type.struct_def,
+                        (field.value.type.struct_def->name + "_").c_str(),
+                        code_ptr);
+    } else {
+      std::string &code = *code_ptr;
+      code += (std::string)", " + nameprefix;
+      code += MakeCamel(field.name, false);
+    }
+  }
+}
+
+// End the creator function signature.
+static void EndBuilderArgs(std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += "):\n";
+}
+
+// Recursively generate struct construction statements and instert manual
+// padding.
+static void StructBuilderBody(const StructDef &struct_def,
+                              const char *nameprefix,
+                              std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += "    builder.Prep(" + NumToString(struct_def.minalign) + ", ";
+  code += NumToString(struct_def.bytesize) + ")\n";
+  for (auto it = struct_def.fields.vec.rbegin();
+       it != struct_def.fields.vec.rend();
+       ++it) {
+    auto &field = **it;
+    if (field.padding)
+      code += "    builder.Pad(" + NumToString(field.padding) + ")\n";
+    if (IsStruct(field.value.type)) {
+      StructBuilderBody(*field.value.type.struct_def,
+                        (field.value.type.struct_def->name + "_").c_str(),
+                        code_ptr);
+    } else {
+      code += "    builder.Prepend" + GenMethod(field) + "(";
+      code += nameprefix + MakeCamel(field.name, false) + ")\n";
+    }
+  }
+}
+
+static void EndBuilderBody(std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += "    return builder.Offset()\n";
+}
+
+// Get the value of a table's starting offset.
+static void GetStartOfTable(const StructDef &struct_def,
+                            std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += "def " + struct_def.name + "Start";
+  code += "(builder): ";
+  code += "builder.StartObject(";
+  code += NumToString(struct_def.fields.vec.size());
+  code += ")\n";
+}
+
+// Set the value of a table's field.
+static void BuildFieldOfTable(const StructDef &struct_def,
+                              const FieldDef &field,
+                              const size_t offset,
+                              std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += "def " + struct_def.name + "Add" + MakeCamel(field.name);
+  code += "(builder, ";
+  code += MakeCamel(field.name, false);
+  code += "): ";
+  code += "builder.Prepend";
+  code += GenMethod(field) + "Slot(";
+  code += NumToString(offset) + ", ";
+  if (!IsScalar(field.value.type.base_type) && (!struct_def.fixed)) {
+    code += "flatbuffers.number_types.UOffsetTFlags.py_type";
+    code += "(";
+    code += MakeCamel(field.name, false) + ")";
+  } else {
+    code += MakeCamel(field.name, false);
+  }
+  code += ", " + field.value.constant;
+  code += ")\n";
+}
+
+// Set the value of one of the members of a table's vector.
+static void BuildVectorOfTable(const StructDef &struct_def,
+                               const FieldDef &field,
+                               std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += "def " + struct_def.name + "Start";
+  code += MakeCamel(field.name);
+  code += "Vector(builder, numElems): return builder.StartVector(";
+  auto vector_type = field.value.type.VectorType();
+  auto alignment = InlineAlignment(vector_type);
+  auto elem_size = InlineSize(vector_type);
+  code += NumToString(elem_size);
+  code += ", numElems, " + NumToString(alignment);
+  code += ")\n";
+}
+
+// Get the offset of the end of a table.
+static void GetEndOffsetOnTable(const StructDef &struct_def,
+                                std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += "def " + struct_def.name + "End";
+  code += "(builder): ";
+  code += "return builder.EndObject()\n";
+}
+
+// Generate the receiver for function signatures.
+static void GenReceiver(const StructDef &struct_def, std::string *code_ptr) {
+  std::string &code = *code_ptr;
+  code += Indent + "# " + struct_def.name + "\n";
+  code += Indent + "def ";
+}
+
+// Generate a struct field, conditioned on its child type(s).
+static void GenStructAccessor(const StructDef &struct_def,
+                              const FieldDef &field,
+                              std::string *code_ptr) {
+  GenComment(field.doc_comment, code_ptr, nullptr, "# ");
+  if (IsScalar(field.value.type.base_type)) {
+    if (struct_def.fixed) {
+      GetScalarFieldOfStruct(struct_def, field, code_ptr);
+    } else {
+      GetScalarFieldOfTable(struct_def, field, code_ptr);
+    }
+  } else {
+    switch (field.value.type.base_type) {
+      case BASE_TYPE_STRUCT:
+        if (struct_def.fixed) {
+          GetStructFieldOfStruct(struct_def, field, code_ptr);
+        } else {
+          GetStructFieldOfTable(struct_def, field, code_ptr);
+        }
+        break;
+      case BASE_TYPE_STRING:
+        GetStringField(struct_def, field, code_ptr);
+        break;
+      case BASE_TYPE_VECTOR: {
+        auto vectortype = field.value.type.VectorType();
+        if (vectortype.base_type == BASE_TYPE_STRUCT) {
+          GetMemberOfVectorOfStruct(struct_def, field, code_ptr);
+        } else {
+          GetMemberOfVectorOfNonStruct(struct_def, field, code_ptr);
+        }
+        break;
+      }
+      case BASE_TYPE_UNION:
+        GetUnionField(struct_def, field, code_ptr);
+        break;
+      default:
+        assert(0);
+    }
+  }
+  if (field.value.type.base_type == BASE_TYPE_VECTOR) {
+    GetVectorLen(struct_def, field, code_ptr);
+  }
+}
+
+// Generate table constructors, conditioned on its members' types.
+static void GenTableBuilders(const StructDef &struct_def,
+                             std::string *code_ptr) {
+  GetStartOfTable(struct_def, code_ptr);
+
+  for (auto it = struct_def.fields.vec.begin();
+       it != struct_def.fields.vec.end();
+       ++it) {
+    auto &field = **it;
+    if (field.deprecated) continue;
+
+    auto offset = it - struct_def.fields.vec.begin();
+    BuildFieldOfTable(struct_def, field, offset, code_ptr);
+    if (field.value.type.base_type == BASE_TYPE_VECTOR) {
+      BuildVectorOfTable(struct_def, field, code_ptr);
+    }
+  }
+
+  GetEndOffsetOnTable(struct_def, code_ptr);
+}
+
+// Generate struct or table methods.
+static void GenStruct(const StructDef &struct_def,
+                      std::string *code_ptr,
+                      StructDef *root_struct_def) {
+  if (struct_def.generated) return;
+
+  GenComment(struct_def.doc_comment, code_ptr, nullptr);
+  BeginClass(struct_def, code_ptr);
+  if (&struct_def == root_struct_def) {
+    // Generate a special accessor for the table that has been declared as
+    // the root type.
+    NewRootTypeFromBuffer(struct_def, code_ptr);
+  }
+  // Generate the Init method that sets the field in a pre-existing
+  // accessor object. This is to allow object reuse.
+  InitializeExisting(struct_def, code_ptr);
+  for (auto it = struct_def.fields.vec.begin();
+       it != struct_def.fields.vec.end();
+       ++it) {
+    auto &field = **it;
+    if (field.deprecated) continue;
+
+    GenStructAccessor(struct_def, field, code_ptr);
+  }
+
+  if (struct_def.fixed) {
+    // create a struct constructor function
+    GenStructBuilder(struct_def, code_ptr);
+  } else {
+    // Create a set of functions that allow table construction.
+    GenTableBuilders(struct_def, code_ptr);
+  }
+}
+
+// Generate enum declarations.
+static void GenEnum(const EnumDef &enum_def, std::string *code_ptr) {
+  if (enum_def.generated) return;
+
+  GenComment(enum_def.doc_comment, code_ptr, nullptr, "# ");
+  BeginEnum(enum_def.name, code_ptr);
+  for (auto it = enum_def.vals.vec.begin();
+       it != enum_def.vals.vec.end();
+       ++it) {
+    auto &ev = **it;
+    GenComment(ev.doc_comment, code_ptr, nullptr, "# ");
+    EnumMember(ev, code_ptr);
+  }
+  EndEnum(code_ptr);
+}
+
+// Returns the function name that is able to read a value of the given type.
+static std::string GenGetter(const Type &type) {
+  switch (type.base_type) {
+    case BASE_TYPE_STRING: return "self._tab.String(";
+    case BASE_TYPE_UNION: return "self._tab.Union(";
+    case BASE_TYPE_VECTOR: return GenGetter(type.VectorType());
+    default:
+      return "self._tab.Get(flatbuffers.number_types." + \
+             MakeCamel(GenTypeGet(type)) + \
+             "Flags, ";
+  }
+}
+
+// Returns the method name for use with add/put calls.
+static std::string GenMethod(const FieldDef &field) {
+  return IsScalar(field.value.type.base_type)
+    ? MakeCamel(GenTypeBasic(field.value.type))
+    : (IsStruct(field.value.type) ? "Struct" : "UOffsetTRelative");
+}
+
+
+// Save out the generated code for a Python Table type.
+static bool SaveType(const Parser &parser, const Definition &def,
+                     const std::string &classcode, const std::string &path,
+                     bool needs_imports) {
+  if (!classcode.length()) return true;
+
+  std::string namespace_name;
+  std::string namespace_dir = path;
+  auto &namespaces = parser.namespaces_.back()->components;
+  for (auto it = namespaces.begin(); it != namespaces.end(); ++it) {
+    if (namespace_name.length()) {
+      namespace_name += ".";
+      namespace_dir += kPathSeparator;
+    }
+    namespace_name = *it;
+    namespace_dir += *it;
+    mkdir(namespace_dir.c_str(), S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH);
+
+    std::string init_py_filename = namespace_dir + "/__init__.py";
+    SaveFile(init_py_filename.c_str(), "", false);
+  }
+
+
+  std::string code = "";
+  BeginFile(namespace_name, needs_imports, &code);
+  code += classcode;
+  std::string filename = namespace_dir + kPathSeparator + def.name + ".py";
+  return SaveFile(filename.c_str(), code, false);
+}
+
+static std::string GenTypeBasic(const Type &type) {
+  static const char *ctypename[] = {
+    #define FLATBUFFERS_TD(ENUM, IDLTYPE, CTYPE, JTYPE, GTYPE, NTYPE, PTYPE) \
+      #PTYPE,
+      FLATBUFFERS_GEN_TYPES(FLATBUFFERS_TD)
+    #undef FLATBUFFERS_TD
+  };
+  return ctypename[type.base_type];
+}
+
+static std::string GenTypePointer(const Type &type) {
+  switch (type.base_type) {
+    case BASE_TYPE_STRING:
+      return "string";
+    case BASE_TYPE_VECTOR:
+      return GenTypeGet(type.VectorType());
+    case BASE_TYPE_STRUCT:
+      return type.struct_def->name;
+    case BASE_TYPE_UNION:
+      // fall through
+    default:
+      return "*flatbuffers.Table";
+  }
+}
+
+static std::string GenTypeGet(const Type &type) {
+  return IsScalar(type.base_type)
+    ? GenTypeBasic(type)
+    : GenTypePointer(type);
+}
+
+static std::string TypeName(const FieldDef &field) {
+  return GenTypeGet(field.value.type);
+}
+
+// Create a struct with a builder and the struct's arguments.
+static void GenStructBuilder(const StructDef &struct_def,
+                             std::string *code_ptr) {
+  BeginBuilderArgs(struct_def, code_ptr);
+  StructBuilderArgs(struct_def, "", code_ptr);
+  EndBuilderArgs(code_ptr);
+
+  StructBuilderBody(struct_def, "", code_ptr);
+  EndBuilderBody(code_ptr);
+}
+
+}  // namespace python
+
+bool GeneratePython(const Parser &parser,
+                    const std::string &path,
+                    const std::string & /*file_name*/,
+                    const GeneratorOptions & /*opts*/) {
+  for (auto it = parser.enums_.vec.begin();
+       it != parser.enums_.vec.end(); ++it) {
+    std::string enumcode;
+    python::GenEnum(**it, &enumcode);
+    if (!python::SaveType(parser, **it, enumcode, path, false))
+      return false;
+  }
+
+  for (auto it = parser.structs_.vec.begin();
+       it != parser.structs_.vec.end(); ++it) {
+    std::string declcode;
+    python::GenStruct(**it, &declcode, parser.root_struct_def);
+    if (!python::SaveType(parser, **it, declcode, path, true))
+      return false;
+  }
+
+  return true;
+}
+
+}  // namespace flatbuffers
+
+