THRIFT-1681: Add Lua Support Patch: Dave Watson

Github Pull Request: This closes #92
diff --git a/compiler/cpp/Makefile.am b/compiler/cpp/Makefile.am
index 5fee856..47725bd 100644
--- a/compiler/cpp/Makefile.am
+++ b/compiler/cpp/Makefile.am
@@ -90,7 +90,8 @@
                   src/generate/t_delphi_generator.cc \
                   src/generate/t_go_generator.cc \
                   src/generate/t_gv_generator.cc \
-                  src/generate/t_d_generator.cc
+                  src/generate/t_d_generator.cc \
+                  src/generate/t_lua_generator.cc
 
 thrift_CPPFLAGS = -I$(srcdir)/src
 thrift_CXXFLAGS = -Wall
diff --git a/compiler/cpp/src/generate/t_lua_generator.cc b/compiler/cpp/src/generate/t_lua_generator.cc
new file mode 100644
index 0000000..b7fdad4
--- /dev/null
+++ b/compiler/cpp/src/generate/t_lua_generator.cc
@@ -0,0 +1,1226 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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.
+ */
+
+#include <sstream>
+#include "t_oop_generator.h"
+#include "platform.h"
+
+using std::ofstream;
+using std::string;
+using std::vector;
+using std::map;
+
+static const string endl = "\n";  // avoid ostream << std::endl flushes
+
+/**
+ * LUA code generator.
+ *
+ */
+class t_lua_generator : public t_oop_generator {
+ public:
+  t_lua_generator(
+      t_program* program,
+      const std::map<std::string, std::string>& parsed_options,
+      const std::string& option_string)
+    : t_oop_generator(program)
+  {
+    std::map<std::string, std::string>::const_iterator iter;
+
+    iter = parsed_options.find("omit_requires");
+    gen_requires_ = (iter == parsed_options.end());
+
+    out_dir_base_ = "gen-lua";
+  }
+
+  /**
+   * Init and close methods
+   */
+  void init_generator();
+  void close_generator();
+
+  /**
+   * Program-level generation functions
+   */
+  void generate_typedef  (t_typedef*  ttypedef);
+  void generate_enum     (t_enum*     tenum);
+  void generate_const    (t_const*    tconst);
+  void generate_struct   (t_struct*   tstruct);
+  void generate_xception (t_struct*   txception);
+  void generate_service  (t_service*  tservice);
+
+  std::string render_const_value(t_type* type, t_const_value* value);
+
+ private:
+
+  /**
+   * True iff we should generate lua require statements.
+   */
+  bool gen_requires_;
+
+  /**
+   * Struct-level generation functions
+   */
+  void generate_lua_struct_definition(
+    std::ofstream& out, t_struct* tstruct, bool is_xception=false);
+  void generate_lua_struct_reader(std::ofstream& out, t_struct* tstruct);
+  void generate_lua_struct_writer(std::ofstream& out, t_struct* tstruct);
+
+  /**
+   * Service-level generation functions
+   */
+  void generate_service_client    (std::ofstream& out, t_service* tservice);
+  void generate_service_interface (std::ofstream& out, t_service* tservice);
+  void generate_service_processor (std::ofstream& out, t_service* tservice);
+  void generate_process_function  (std::ofstream& out, t_service* tservice,
+                                   t_function* tfunction);
+  void generate_service_helpers   (ofstream &out, t_service* tservice);
+  void generate_function_helpers  (ofstream &out, t_function* tfunction);
+
+  /**
+   * Deserialization (Read)
+   */
+  void generate_deserialize_field(
+    std::ofstream &out, t_field *tfield, std::string prefix="");
+
+  void generate_deserialize_struct(
+    std::ofstream &out, t_struct *tstruct, std::string prefix="");
+
+  void generate_deserialize_container(
+    std::ofstream &out, t_type *ttype, std::string prefix="");
+
+  void generate_deserialize_set_element(
+    std::ofstream &out, t_set *tset, std::string prefix="");
+
+  void generate_deserialize_map_element(
+    std::ofstream &out, t_map *tmap, std::string prefix="");
+
+  void generate_deserialize_list_element(
+    std::ofstream &out, t_list *tlist, std::string prefix="");
+
+  /**
+   * Serialization (Write)
+   */
+  void generate_serialize_field(
+    std::ofstream &out, t_field *tfield, std::string prefix="");
+
+  void generate_serialize_struct(
+    std::ofstream &out, t_struct *tstruct, std::string prefix="");
+
+  void generate_serialize_container(
+    std::ofstream &out, t_type *ttype, std::string prefix="");
+
+  void generate_serialize_map_element(
+    std::ofstream &out, t_map *tmap, std::string kiter, std::string viter);
+
+  void generate_serialize_set_element(
+    std::ofstream &out, t_set *tmap, std::string iter);
+
+  void generate_serialize_list_element(
+    std::ofstream &out, t_list *tlist, std::string iter);
+
+  /**
+   * Helper rendering functions
+   */
+  std::string lua_includes();
+  std::string function_signature(t_function* tfunction, std::string prefix="");
+  std::string argument_list(t_struct* tstruct, std::string prefix="");
+  std::string type_to_enum(t_type* ttype);
+  static std::string get_namespace(const t_program* program);
+
+  std::string autogen_comment() {
+    return
+      std::string("--\n") +
+      "-- Autogenerated by Thrift\n" +
+      "--\n" +
+      "-- DO NOT EDIT UNLESS YOU ARE SURE THAT YOU KNOW WHAT YOU ARE DOING\n" +
+      "-- @""generated\n" +
+      "--\n";
+  }
+
+  /**
+   * File streams
+   */
+  std::ofstream f_types_;
+  std::ofstream f_consts_;
+  std::ofstream f_service_;
+};
+
+
+/**
+ * Init and close methods
+ */
+void t_lua_generator::init_generator() {
+  // Make output directory
+  string outdir = get_out_dir();
+  MKDIR(outdir.c_str());
+
+  // Make output files
+  string cur_namespace = get_namespace(program_);
+  string f_consts_name = outdir + cur_namespace + "constants.lua";
+  f_consts_.open(f_consts_name.c_str());
+  string f_types_name = outdir + cur_namespace + "ttypes.lua";
+  f_types_.open(f_types_name.c_str());
+
+  // Add headers
+  f_consts_ << autogen_comment() << lua_includes();
+  f_types_ << autogen_comment() << lua_includes();
+  if (gen_requires_) {
+    f_types_ << endl << "require '" << cur_namespace << "constants'";
+  }
+}
+
+void t_lua_generator::close_generator() {
+  // Close types file
+  f_types_.close();
+  f_consts_.close();
+}
+
+/**
+ * Generate a typedef (essentially a constant)
+ */
+void t_lua_generator::generate_typedef(t_typedef* ttypedef) {
+  f_types_
+    << endl << endl << indent()
+    << ttypedef->get_symbolic() << " = "
+    << ttypedef->get_type()->get_name();
+}
+
+/**
+ * Generates code for an enumerated type (table)
+ */
+void t_lua_generator::generate_enum(t_enum* tenum) {
+  f_types_ << endl << endl << tenum->get_name() << " = {" << endl;
+
+  vector<t_enum_value*> constants = tenum->get_constants();
+  vector<t_enum_value*>::iterator c_iter;
+  for (c_iter = constants.begin(); c_iter != constants.end();) {
+    int32_t value = (*c_iter)->get_value();
+
+    f_types_ << "  " << (*c_iter)->get_name() << " = " << value;
+    ++c_iter;
+    if (c_iter != constants.end()) {
+      f_types_ << ",";
+    }
+    f_types_ << endl;
+  }
+  f_types_ << "}";
+}
+
+/**
+ * Generate a constant (non-local) value
+ */
+void t_lua_generator::generate_const(t_const* tconst) {
+  t_type* type = tconst->get_type();
+  string name = tconst->get_name();
+  t_const_value* value = tconst->get_value();
+
+  f_consts_ << endl << endl << name << " = ";
+  f_consts_ << render_const_value(type, value);
+}
+
+/**
+ * Prints the value of a constant with the given type.
+ */
+string t_lua_generator::render_const_value(
+  t_type* type, t_const_value* value) {
+  std::ostringstream out;
+
+  type = get_true_type(type);
+  if (type->is_base_type()) {
+    t_base_type::t_base tbase = ((t_base_type*)type)->get_base();
+    switch (tbase) {
+    case t_base_type::TYPE_STRING:
+      out << "'" << value->get_string() << "'";
+      break;
+    case t_base_type::TYPE_BOOL:
+      out << (value->get_integer() > 0 ? "true" : "false");
+      break;
+    case t_base_type::TYPE_BYTE:
+    case t_base_type::TYPE_I16:
+    case t_base_type::TYPE_I32:
+      out << value->get_integer();
+      break;
+    case t_base_type::TYPE_I64:
+      out << "lualongnumber.new('" << value->get_string() << "')";
+      break;
+    case t_base_type::TYPE_DOUBLE:
+      if (value->get_type() == t_const_value::CV_INTEGER) {
+        out << value->get_integer();
+      } else {
+        out << value->get_double();
+      }
+      break;
+    default:
+      throw "compiler error: no const of base type "
+        + t_base_type::t_base_name(tbase);
+    }
+  } else if (type->is_enum()) {
+    out << value->get_integer();
+  } else if (type->is_struct() || type->is_xception()) {
+    out << type->get_name() << " = {" << endl;
+    indent_up();
+
+    const vector<t_field*>& fields = ((t_struct*)type)->get_members();
+    vector<t_field*>::const_iterator f_iter;
+    const map<t_const_value*, t_const_value*>& val = value->get_map();
+    map<t_const_value*, t_const_value*>::const_iterator v_iter;
+    for (v_iter = val.begin(); v_iter != val.end();) {
+      t_type* field_type = NULL;
+      for (f_iter = fields.begin(); f_iter != fields.end(); ++f_iter) {
+        if ((*f_iter)->get_name() == v_iter->first->get_string()) {
+          field_type = (*f_iter)->get_type();
+        }
+      }
+      if (field_type == NULL) {
+        throw "type error: " + type->get_name() + " has no field "
+          + v_iter->first->get_string();
+      }
+
+      indent(out);
+      out << render_const_value(g_type_string, v_iter->first);
+      out << " = ";
+      out << render_const_value(field_type, v_iter->second);
+      ++v_iter;
+      if (v_iter != val.end()) {
+        out << ",";
+      }
+    }
+
+    out << "}";
+    indent_down();
+  } else if (type->is_map()) {
+    out << type->get_name() << "{" << endl;
+    indent_up();
+
+    t_type* ktype = ((t_map*)type)->get_key_type();
+    t_type* vtype = ((t_map*)type)->get_val_type();
+
+    const map<t_const_value*, t_const_value*>& val = value->get_map();
+    map<t_const_value*, t_const_value*>::const_iterator v_iter;
+    for (v_iter = val.begin(); v_iter != val.end();) {
+      indent(out)
+        << "[" << render_const_value(ktype, v_iter->first) << "] = "
+        << render_const_value(vtype, v_iter->second);
+      ++v_iter;
+      if (v_iter != val.end()) {
+        out << ",";
+      }
+      out << endl;
+    }
+    indent_down();
+    indent(out) << "}";
+  } else if (type->is_list() || type->is_set()) {
+    t_type* etype;
+    if (type->is_list()) {
+      etype = ((t_list*)type)->get_elem_type();
+    } else {
+      etype = ((t_set*)type)->get_elem_type();
+    }
+    out << type->get_name() << " = {" << endl;
+    const vector<t_const_value*>& val = value->get_list();
+    vector<t_const_value*>::const_iterator v_iter;
+    for (v_iter = val.begin(); v_iter != val.end();) {
+      indent(out);
+      out << "[" << render_const_value(etype, *v_iter) << "]";
+      if (type->is_set()) {
+        out << " = true";
+      } else {
+        out << " = false";
+      }
+      ++v_iter;
+      if (v_iter != val.end()) {
+        out << "," << endl;
+      }
+    }
+    out << "}";
+  }
+  return out.str();
+}
+
+/**
+ * Generate a thrift struct
+ */
+void t_lua_generator::generate_struct(t_struct* tstruct) {
+  generate_lua_struct_definition(f_types_, tstruct, false);
+}
+
+/**
+ * Generate a thrift exception
+ */
+void t_lua_generator::generate_xception(t_struct* txception) {
+  generate_lua_struct_definition(f_types_, txception, true);
+}
+
+/**
+ * Generate a thrift struct or exception (lua table)
+ */
+void t_lua_generator::generate_lua_struct_definition(ofstream &out,
+                                                     t_struct *tstruct,
+                                                     bool is_exception) {
+  vector<t_field*>::const_iterator m_iter;
+  const vector<t_field*>& members = tstruct->get_members();
+
+  indent(out) << endl << endl << tstruct->get_name();
+  if (is_exception) {
+    out << " = TException:new{" << endl <<
+      indent() << "  __type = '" << tstruct->get_name() << "'";
+    if (members.size() > 0) {
+      out << ",";
+    }
+    out << endl;
+  } else {
+    out << " = __TObject:new{" << endl;
+  }
+  indent_up();
+  for (m_iter = members.begin(); m_iter != members.end();) {
+    indent(out);
+    out << (*m_iter)->get_name();
+    ++m_iter;
+    if (m_iter != members.end()) {
+      out << "," << endl;
+    }
+  }
+  indent_down();
+  indent(out);
+  out << endl << "}";
+
+  generate_lua_struct_reader(out, tstruct);
+  generate_lua_struct_writer(out, tstruct);
+}
+
+/**
+ * Generate a struct/exception reader
+ */
+void t_lua_generator::generate_lua_struct_reader(ofstream& out,
+                                                  t_struct* tstruct) {
+  const vector<t_field*>& fields = tstruct->get_members();
+  vector<t_field*>::const_iterator f_iter;
+
+  // function
+  indent(out) << endl << endl
+    << "function " << tstruct->get_name() << ":read(iprot)" << endl;
+  indent_up();
+
+  indent(out) << "iprot:readStructBegin()" << endl;
+
+  // while: Read in fields
+  indent(out) << "while true do" << endl;
+    indent_up();
+
+    // if: Check what to read
+    indent(out) << "local fname, ftype, fid = iprot:readFieldBegin()" << endl;
+    indent(out) << "if ftype == TType.STOP then" << endl;
+      indent_up();
+      indent(out) << "break" << endl;
+
+      for (f_iter = fields.begin(); f_iter != fields.end(); ++f_iter) {
+        indent_down();
+        indent(out)
+          << "elseif fid == " << (*f_iter)->get_key() << " then" << endl;
+          indent_up();
+          indent(out)
+            << "if ftype == " << type_to_enum((*f_iter)->get_type())
+            << " then" << endl;
+            indent_up();
+
+            // Read field contents
+            generate_deserialize_field(out, *f_iter, "self.");
+
+            indent_down();
+          indent(out) << "else" << endl;
+          indent(out) << "  iprot:skip(ftype)" << endl;
+          indent(out) << "end" << endl;
+      }
+
+    // end if
+    indent_down();
+    indent(out) << "else" << endl;
+    indent(out) << "  iprot:skip(ftype)" << endl;
+    indent(out) << "end" << endl;
+    indent(out) << "iprot:readFieldEnd()" << endl;
+
+  // end while
+    indent_down();
+  indent(out) << "end" << endl;
+  indent(out) << "iprot:readStructEnd()" << endl;
+
+  // end function
+  indent_down();
+  indent(out);
+  out << "end";
+}
+
+/**
+ * Generate a struct/exception writer
+ */
+void t_lua_generator::generate_lua_struct_writer(ofstream& out,
+                                                  t_struct* tstruct) {
+  const vector<t_field*>& fields = tstruct->get_members();
+  vector<t_field*>::const_iterator f_iter;
+
+  // function
+  indent(out) << endl << endl
+    << "function " << tstruct->get_name() << ":write(oprot)" << endl;
+  indent_up();
+
+    indent(out)
+      << "oprot:writeStructBegin('" << tstruct->get_name() << "')" << endl;
+    for (f_iter = fields.begin(); f_iter != fields.end(); ++f_iter) {
+      indent(out) << "if self." << (*f_iter)->get_name() << " then" << endl;
+      indent_up();
+        indent(out)
+          << "oprot:writeFieldBegin('" << (*f_iter)->get_name() << "', "
+          << type_to_enum((*f_iter)->get_type()) << ", "
+          << (*f_iter)->get_key() << ")" << endl;
+
+        // Write field contents
+        generate_serialize_field(out, *f_iter, "self.");
+
+        indent(out)
+          << "oprot:writeFieldEnd()" << endl;
+      indent_down();
+      indent(out) << "end" << endl;
+    }
+    indent(out) << "oprot:writeFieldStop()" << endl;
+    indent(out) << "oprot:writeStructEnd()" << endl;
+
+  // end function
+  indent_down();
+  indent(out);
+  out << "end";
+}
+
+/**
+ * Generate a thrift service
+ */
+void t_lua_generator::generate_service(t_service* tservice) {
+  // Get output directory
+  string outdir = get_out_dir();
+
+  // Open the file for writing
+  string cur_ns = get_namespace(program_);
+  string f_service_name = outdir + cur_ns + tservice->get_name() + ".lua";
+  f_service_.open(f_service_name.c_str());
+
+  // Headers
+  f_service_ << autogen_comment() << lua_includes();
+  if (gen_requires_) {
+    f_service_ << endl << "require '" << cur_ns << "ttypes'" << endl;
+
+    if (tservice->get_extends() != NULL) {
+      f_service_
+        << "require '" << get_namespace(tservice->get_extends()->get_program())
+        << tservice->get_extends()->get_name() << "'" << endl;
+    }
+  }
+
+  f_service_ << endl;
+
+  generate_service_client(f_service_, tservice);
+  generate_service_interface(f_service_, tservice);
+  generate_service_processor(f_service_, tservice);
+  generate_service_helpers(f_service_, tservice);
+
+  // Close the file
+  f_service_.close();
+}
+
+void t_lua_generator::generate_service_interface(ofstream &out,
+                                                 t_service* tservice) {
+  string classname = tservice->get_name() + "Iface";
+  t_service* extends_s = tservice->get_extends();
+
+  // Interface object definition
+  out << classname << " = ";
+  if (extends_s) {
+    out << extends_s->get_name() << "Iface:new{" << endl;
+  } else {
+    out << "__TObject:new{" << endl;
+  }
+  out
+    << "  __type = '" << classname << "'" << endl
+    << "}" << endl << endl;
+}
+
+void t_lua_generator::generate_service_client(ofstream &out,
+                                              t_service* tservice) {
+  string classname = tservice->get_name() + "Client";
+  t_service* extends_s = tservice->get_extends();
+
+  // Client object definition
+  out << classname << " = __TObject.new(";
+  if (extends_s != NULL) {
+    out << extends_s->get_name() << "Client";
+  } else {
+    out << "__TClient";
+  }
+  out
+    <<", {" << endl
+    << "  __type = '" << classname << "'" << endl
+    << "})" << endl;
+
+  // Send/Recv functions
+  vector<t_function*> functions = tservice->get_functions();
+  vector<t_function*>::const_iterator f_iter;
+  for (f_iter = functions.begin(); f_iter != functions.end(); ++f_iter) {
+    string sig = function_signature(*f_iter);
+    string funcname = (*f_iter)->get_name();
+
+    // Wrapper function
+    indent(out) << endl << "function " << classname << ":" << sig << endl;
+      indent_up();
+
+      indent(out) << "self:send_" << sig << endl << indent();
+      if (!(*f_iter)->is_oneway()) {
+        if (!(*f_iter)->get_returntype()->is_void()) {
+          out << "return ";
+        }
+        out << "self:recv_" << sig << endl;
+      }
+
+      indent_down();
+    indent(out) << "end" << endl;
+
+    // Send function
+    indent(out) << endl << "function " << classname << ":send_" << sig << endl;
+      indent_up();
+
+      indent(out) << "self.oprot:writeMessageBegin('" << funcname <<
+        "', TMessageType.CALL, self._seqid)" << endl;
+      indent(out) << "local args = " << funcname << "_args:new{}" << endl;
+
+      // Set the args
+      const vector<t_field*>& args = (*f_iter)->get_arglist()->get_members();
+      vector<t_field*>::const_iterator fld_iter;
+      for (fld_iter = args.begin(); fld_iter != args.end(); ++fld_iter) {
+        std::string argname = (*fld_iter)->get_name();
+        indent(out) << "args." << argname << " = " << argname << endl;
+      }
+
+      indent(out) << "args:write(self.oprot)" << endl;
+      indent(out) << "self.oprot:writeMessageEnd()" << endl;
+      indent(out) << "self.oprot.trans:flush()" << endl;
+
+      indent_down();
+    indent(out) << "end" << endl;
+
+    // Recv function
+    if (!(*f_iter)->is_oneway()) {
+      indent(out)
+        << endl << "function " << classname << ":recv_" << sig << endl;
+        indent_up();
+
+        out <<
+          indent() << "local fname, mtype, rseqid = self.iprot:"
+                   << "readMessageBegin()"<< endl <<
+          indent() << "if mtype == TMessageType.EXCEPTION then" << endl <<
+          indent() << "  local x = TApplicationException:new{}" << endl <<
+          indent() << "  x:read(self.iprot)" << endl <<
+          indent() << "  self.iprot:readMessageEnd()" << endl <<
+          indent() << "  error(x)" << endl <<
+          indent() << "end" << endl <<
+          indent() << "local result = " << funcname << "_result:new{}"
+                   << endl <<
+          indent() << "result:read(self.iprot)" << endl <<
+          indent() << "self.iprot:readMessageEnd()" << endl;
+
+        // Return the result if it's not a void function
+        if (!(*f_iter)->get_returntype()->is_void()) {
+          out <<
+            indent() << "if result.success then" << endl <<
+            indent() << "  return result.success" << endl;
+
+          // Throw custom exceptions
+          const std::vector<t_field*>& xf =
+            (*f_iter)->get_xceptions()->get_members();
+          vector<t_field*>::const_iterator x_iter;
+          for (x_iter = xf.begin(); x_iter != xf.end(); ++x_iter) {
+            out <<
+              indent() << "elseif result." << (*x_iter)->get_name() << " then"
+                       << endl <<
+              indent() << "  error(result." << (*x_iter)->get_name() << ")"
+                       << endl;
+          }
+
+          out <<
+            indent() << "end" << endl <<
+            indent() << "error(TApplicationException:new{errorCode = "
+                     << "TApplicationException.MISSING_RESULT})" << endl;
+        }
+
+        indent_down();
+      indent(out) << "end" << endl;
+    }
+  }
+}
+
+void t_lua_generator::generate_service_processor(ofstream &out,
+                                                 t_service* tservice) {
+  string classname = tservice->get_name() + "Processor";
+  t_service* extends_s = tservice->get_extends();
+
+  // Define processor table
+  out << endl
+    << classname << " = __TObject.new(";
+  if (extends_s != NULL) {
+    out << extends_s << "Processor" << endl;
+  } else {
+    out << "__TProcessor" << endl;
+  }
+  out
+    << ", {" << endl
+    << " __type = '" << classname << "'" << endl
+    << "})" << endl;
+
+  // Process function
+  indent(out) << endl << "function " << classname
+    << ":process(iprot, oprot, server_ctx)" << endl;
+    indent_up();
+
+    indent(out)
+      << "local name, mtype, seqid = iprot:readMessageBegin()" << endl;
+    indent(out)
+      << "local func_name = 'process_' .. name" << endl;
+    indent(out)
+      << "if not self[func_name] or ttype(self[func_name]) ~= 'function' then";
+    indent_up();
+      out << endl <<
+        indent() << "iprot:skip(TType.STRUCT)" << endl <<
+        indent() << "iprot:readMessageEnd()" << endl <<
+        indent() << "x = TApplicationException:new{" << endl <<
+        indent() << "  errorCode = TApplicationException.UNKNOWN_METHOD" << endl
+     << indent() << "}" << endl <<
+        indent() << "oprot:writeMessageBegin(name, TMessageType.EXCEPTION, "
+                 << "seqid)" << endl <<
+        indent() << "x:write(oprot)" << endl <<
+        indent() << "oprot:writeMessageEnd()" << endl <<
+        indent() << "oprot.trans:flush()" << endl;
+    indent_down();
+    indent(out) << "else" << endl <<
+       indent() << "  self[func_name](self, seqid, iprot, oprot, server_ctx)"
+                << endl
+    << indent() << "end" << endl;
+
+    indent_down();
+  indent(out) << "end" << endl;
+
+  // Generate the process subfunctions
+  vector<t_function*> functions = tservice->get_functions();
+  vector<t_function*>::iterator f_iter;
+  for (f_iter = functions.begin(); f_iter != functions.end(); ++f_iter) {
+    generate_process_function(out, tservice, *f_iter);
+  }
+}
+
+void t_lua_generator::generate_process_function(ofstream &out,
+                                                t_service* tservice,
+                                                t_function* tfunction) {
+  string classname = tservice->get_name() + "Processor";
+  string argsname = tfunction->get_name() + "_args";
+  string resultname = tfunction->get_name() + "_result";
+  string fn_name = tfunction->get_name();
+
+  indent(out) << endl << "function " << classname << ":process_" << fn_name
+    << "(seqid, iprot, oprot, server_ctx)" << endl;
+    indent_up();
+
+    // Read the request
+    out <<
+      indent() << "local args = " << argsname << ":new{}" << endl <<
+      indent() << "local reply_type = TMessageType.REPLY" << endl <<
+      indent() << "args:read(iprot)" << endl <<
+      indent() << "iprot:readMessageEnd()" << endl <<
+      indent() << "local result = " << resultname << ":new{}" << endl <<
+      indent() << "local status, res = pcall(self.handler." << fn_name
+               << ", self.handler";
+
+    // Print arguments
+    t_struct *args = tfunction->get_arglist();
+    if (args->get_members().size() > 0) {
+      out << ", " << argument_list(args, "args.");
+    }
+
+    // Check for errors
+    out << ")" << endl <<
+      indent() << "if not status then" << endl <<
+      indent() << "  reply_type = TMessageType.EXCEPTION" << endl <<
+      indent() << "  result = TApplicationException:new{message = res}"
+               << endl;
+
+    // Handle custom exceptions
+    const std::vector<t_field*>& xf = tfunction->get_xceptions()->get_members();
+    if (xf.size() > 0) {
+      vector<t_field*>::const_iterator x_iter;
+      for (x_iter = xf.begin(); x_iter != xf.end(); ++x_iter) {
+        out <<
+          indent() << "elseif ttype(res) == '"
+                   << (*x_iter)->get_type()->get_name() << "' then" << endl <<
+          indent() << "  result." << (*x_iter)->get_name() << " = res" << endl;
+      }
+    }
+
+    // Set the result and write the reply
+    out <<
+      indent() << "else" << endl <<
+      indent() << "  result.success = res" << endl <<
+      indent() << "end" << endl <<
+      indent() << "oprot:writeMessageBegin('" << fn_name << "', reply_type, "
+               << "seqid)" << endl <<
+      indent() << "result:write(oprot)" << endl <<
+      indent() << "oprot:writeMessageEnd()" << endl <<
+      indent() << "oprot.trans:flush()" << endl;
+
+    indent_down();
+  indent(out) << "end" << endl;
+}
+
+// Service helpers
+void t_lua_generator::generate_service_helpers(ofstream &out,
+                                               t_service* tservice) {
+  vector<t_function*> functions = tservice->get_functions();
+  vector<t_function*>::iterator f_iter;
+
+  out << endl << "-- HELPER FUNCTIONS AND STRUCTURES";
+  for (f_iter = functions.begin(); f_iter != functions.end(); ++f_iter) {
+    t_struct* ts = (*f_iter)->get_arglist();
+    generate_lua_struct_definition(out, ts, false);
+    generate_function_helpers(out, *f_iter);
+  }
+}
+
+void t_lua_generator::generate_function_helpers(ofstream &out,
+                                                t_function *tfunction) {
+  if (!tfunction->is_oneway()) {
+    t_struct result(program_, tfunction->get_name() + "_result");
+    t_field success(tfunction->get_returntype(), "success", 0);
+    if (!tfunction->get_returntype()->is_void()) {
+      result.append(&success);
+    }
+
+    t_struct* xs = tfunction->get_xceptions();
+    const vector<t_field*>& fields = xs->get_members();
+    vector<t_field*>::const_iterator f_iter;
+    for (f_iter = fields.begin(); f_iter != fields.end(); ++f_iter) {
+      result.append(*f_iter);
+    }
+    generate_lua_struct_definition(out, &result, false);
+  }
+}
+
+/**
+ * Deserialize (Read)
+ */
+void t_lua_generator::generate_deserialize_field(ofstream &out,
+                                                 t_field* tfield,
+                                                 string prefix) {
+  t_type* type = get_true_type(tfield->get_type());
+
+  if (type->is_void()) {
+    throw "CANNOT GENERATE DESERIALIZE CODE FOR void TYPE: " +
+      prefix + tfield->get_name();
+  }
+
+  string name = prefix + tfield->get_name();
+
+  if (type->is_struct() || type->is_xception()) {
+    generate_deserialize_struct(out, (t_struct*)type, name);
+  } else if (type->is_container()) {
+    generate_deserialize_container(out, type, name);
+  } else if (type->is_base_type() || type->is_enum()) {
+    indent(out) <<
+      name << " = iprot:";
+
+    if (type->is_base_type()) {
+      t_base_type::t_base tbase = ((t_base_type*)type)->get_base();
+      switch (tbase) {
+      case t_base_type::TYPE_VOID:
+        throw "compiler error: cannot serialize void field in a struct: " +
+          name;
+        break;
+      case t_base_type::TYPE_STRING:
+        out << "readString()";
+        break;
+      case t_base_type::TYPE_BOOL:
+        out << "readBool()";
+        break;
+      case t_base_type::TYPE_BYTE:
+        out << "readByte()";
+        break;
+      case t_base_type::TYPE_I16:
+        out << "readI16()";
+        break;
+      case t_base_type::TYPE_I32:
+        out << "readI32()";
+        break;
+      case t_base_type::TYPE_I64:
+        out << "readI64()";
+        break;
+      case t_base_type::TYPE_DOUBLE:
+        out << "readDouble()";
+        break;
+      default:
+        throw "compiler error: no PHP name for base type " +
+          t_base_type::t_base_name(tbase);
+      }
+    } else if (type->is_enum()) {
+      out << "readI32()";
+    }
+    out << endl;
+
+  } else {
+    printf("DO NOT KNOW HOW TO DESERIALIZE FIELD '%s' TYPE '%s'\n",
+           tfield->get_name().c_str(), type->get_name().c_str());
+  }
+}
+
+void t_lua_generator::generate_deserialize_struct(ofstream &out,
+                                                  t_struct* tstruct,
+                                                  string prefix) {
+  indent(out)
+    << prefix << " = " << tstruct->get_name() << ":new{}" << endl
+    << indent() << prefix << ":read(iprot)" << endl;
+}
+
+void t_lua_generator::generate_deserialize_container(ofstream &out,
+                                                     t_type* ttype,
+                                                     string prefix) {
+  string size = tmp("_size");
+  string ktype = tmp("_ktype");
+  string vtype = tmp("_vtype");
+  string etype = tmp("_etype");
+
+  t_field fsize(g_type_i32, size);
+  t_field fktype(g_type_byte, ktype);
+  t_field fvtype(g_type_byte, vtype);
+  t_field fetype(g_type_byte, etype);
+
+  // Declare variables, read header
+  indent(out) << prefix << " = {}" << endl;
+  if (ttype->is_map()) {
+    indent(out) << "local " << ktype << ", " << vtype << ", " << size
+                << " = iprot:readMapBegin() " << endl;
+  } else if (ttype->is_set()) {
+    indent(out) << "local " << etype << ", " << size
+                << " = iprot:readSetBegin()" << endl;
+  } else if (ttype->is_list()) {
+    indent(out) << "local " << etype << ", " << size
+                << " = iprot:readListBegin()" << endl;
+  }
+
+  // Deserialize
+  indent(out) << "for _i=1," << size << " do" << endl;
+    indent_up();
+
+    if (ttype->is_map()) {
+      generate_deserialize_map_element(out, (t_map*)ttype, prefix);
+    } else if (ttype->is_set()) {
+      generate_deserialize_set_element(out, (t_set*)ttype, prefix);
+    } else if (ttype->is_list()) {
+      generate_deserialize_list_element(out, (t_list*)ttype, prefix);
+    }
+
+    indent_down();
+  indent(out) << "end" << endl;
+
+  // Read container end
+  if (ttype->is_map()) {
+    indent(out) << "iprot:readMapEnd()" << endl;
+  } else if (ttype->is_set()) {
+    indent(out) << "iprot:readSetEnd()" << endl;
+  } else if (ttype->is_list()) {
+    indent(out) << "iprot:readListEnd()" << endl;
+  }
+}
+
+void t_lua_generator::generate_deserialize_map_element(ofstream &out,
+                                                       t_map* tmap,
+                                                       string prefix) {
+  // A map is represented by a table indexable by any lua type
+  string key = tmp("_key");
+  string val = tmp("_val");
+  t_field fkey(tmap->get_key_type(), key);
+  t_field fval(tmap->get_val_type(), val);
+
+  generate_deserialize_field(out, &fkey);
+  generate_deserialize_field(out, &fval);
+
+  indent(out) << prefix << "[" << key << "] = " << val << endl;
+}
+
+void t_lua_generator::generate_deserialize_set_element(ofstream &out,
+                                                       t_set* tset,
+                                                       string prefix) {
+  // A set is represented by a table indexed by the value
+  string elem = tmp("_elem");
+  t_field felem(tset->get_elem_type(), elem);
+
+  generate_deserialize_field(out, &felem);
+
+  indent(out) <<
+    prefix << "[" << elem << "] = " << elem << endl;
+}
+
+void t_lua_generator::generate_deserialize_list_element(ofstream &out,
+                                                        t_list* tlist,
+                                                        string prefix) {
+  // A list is represented by a table indexed by integer values
+  // LUA natively provides all of the functions required to maintain a list
+  string elem = tmp("_elem");
+  t_field felem(tlist->get_elem_type(), elem);
+
+  generate_deserialize_field(out, &felem);
+
+  indent(out) << "table.insert(" << prefix << ", " << elem << ")" << endl;
+}
+
+/**
+ * Serialize (Write)
+ */
+void t_lua_generator::generate_serialize_field(ofstream &out,
+                                               t_field* tfield,
+                                               string prefix) {
+  t_type* type = get_true_type(tfield->get_type());
+  string name = prefix + tfield->get_name();
+
+  // Do nothing for void types
+  if (type->is_void()) {
+    throw "CANNOT GENERATE SERIALIZE CODE FOR void TYPE: " + name;
+  }
+
+  if (type->is_struct() || type->is_xception()) {
+    generate_serialize_struct(out, (t_struct*)type, name);
+  } else if (type->is_container()) {
+    generate_serialize_container(out, type, name);
+  } else if (type->is_base_type() || type->is_enum()) {
+    indent(out) << "oprot:";
+
+    if (type->is_base_type()) {
+      t_base_type::t_base tbase = ((t_base_type*)type)->get_base();
+      switch (tbase) {
+      case t_base_type::TYPE_VOID:
+        throw
+          "compiler error: cannot serialize void field in a struct: " + name;
+        break;
+      case t_base_type::TYPE_STRING:
+        out << "writeString(" << name << ")";
+        break;
+      case t_base_type::TYPE_BOOL:
+        out << "writeBool(" << name << ")";
+        break;
+      case t_base_type::TYPE_BYTE:
+        out << "writeByte(" << name << ")";
+        break;
+      case t_base_type::TYPE_I16:
+        out << "writeI16(" << name << ")";
+        break;
+      case t_base_type::TYPE_I32:
+        out << "writeI32(" << name << ")";
+        break;
+      case t_base_type::TYPE_I64:
+        out << "writeI64(" << name << ")";
+        break;
+      case t_base_type::TYPE_DOUBLE:
+        out << "writeDouble(" << name << ")";
+        break;
+      default:
+        throw "compiler error: no PHP name for base type " +
+          t_base_type::t_base_name(tbase);
+      }
+    } else if (type->is_enum()) {
+      out << "writeI32(" << name << ")";
+    }
+    out << endl;
+  } else {
+    printf("DO NOT KNOW HOW TO SERIALIZE FIELD '%s' TYPE '%s'\n",
+           name.c_str(),
+           type->get_name().c_str());
+  }
+}
+
+void t_lua_generator::generate_serialize_struct(ofstream &out,
+                                                t_struct* tstruct,
+                                                string prefix) {
+  indent(out) << prefix << ":write(oprot)" << endl;
+}
+
+void t_lua_generator::generate_serialize_container(ofstream &out,
+                                                   t_type* ttype,
+                                                   string prefix) {
+  // Begin writing
+  if (ttype->is_map()) {
+    indent(out) <<
+      "oprot:writeMapBegin(" <<
+      type_to_enum(((t_map*)ttype)->get_key_type()) << ", " <<
+      type_to_enum(((t_map*)ttype)->get_val_type()) << ", " <<
+      "string.len(" << prefix << "))" << endl;
+  } else if (ttype->is_set()) {
+    indent(out) <<
+      "oprot:writeSetBegin(" <<
+      type_to_enum(((t_set*)ttype)->get_elem_type()) << ", " <<
+      "string.len(" << prefix << "))" << endl;
+  } else if (ttype->is_list()) {
+    indent(out) <<
+      "oprot:writeListBegin(" <<
+      type_to_enum(((t_list*)ttype)->get_elem_type()) << ", " <<
+      "string.len(" << prefix << "))" << endl;
+  }
+
+  // Serialize
+  if (ttype->is_map()) {
+    string kiter = tmp("kiter");
+    string viter = tmp("viter");
+    indent(out)
+      << "for " << kiter << "," << viter << " in pairs(" << prefix << ") do"
+      << endl;
+      indent_up();
+      generate_serialize_map_element(out, (t_map*)ttype, kiter, viter);
+      indent_down();
+    indent(out) << "end" << endl;
+  } else if (ttype->is_set()) {
+    string iter = tmp("iter");
+    indent(out) <<
+      "for " << iter << ",_ in pairs(" << prefix << ") do" << endl;
+      indent_up();
+      generate_serialize_set_element(out, (t_set*)ttype, iter);
+      indent_down();
+    indent(out) << "end" << endl;
+  } else if (ttype->is_list()) {
+    string iter = tmp("iter");
+    indent(out) <<
+      "for _," << iter << " in ipairs(" << prefix << ") do" << endl;
+      indent_up();
+      generate_serialize_list_element(out, (t_list*)ttype, iter);
+      indent_down();
+    indent(out) << "end" << endl;
+  }
+
+  // Finish writing
+  if (ttype->is_map()) {
+    indent(out) << "oprot:writeMapEnd()" << endl;
+  } else if (ttype->is_set()) {
+    indent(out) << "oprot:writeSetEnd()" << endl;
+  } else if (ttype->is_list()) {
+    indent(out) << "oprot:writeListEnd()" << endl;
+  }
+}
+
+void t_lua_generator::generate_serialize_map_element(ofstream &out,
+                                                     t_map* tmap,
+                                                     string kiter,
+                                                     string viter) {
+  t_field kfield(tmap->get_key_type(), kiter);
+  generate_serialize_field(out, &kfield, "");
+
+  t_field vfield(tmap->get_val_type(), viter);
+  generate_serialize_field(out, &vfield, "");
+}
+
+void t_lua_generator::generate_serialize_set_element(ofstream &out,
+                                                     t_set* tset,
+                                                     string iter) {
+  t_field efield(tset->get_elem_type(), iter);
+  generate_serialize_field(out, &efield, "");
+}
+
+void t_lua_generator::generate_serialize_list_element(ofstream &out,
+                                                      t_list* tlist,
+                                                      string iter) {
+  t_field efield(tlist->get_elem_type(), iter);
+  generate_serialize_field(out, &efield, "");
+}
+
+/**
+ *  Helper rendering functions
+ */
+string t_lua_generator::lua_includes() {
+  if (gen_requires_) {
+    return "\n\nrequire 'Thrift'";
+  } else {
+    return "";
+  }
+}
+
+string t_lua_generator::get_namespace(const t_program* program) {
+  std::string real_module = program->get_namespace("lua");
+  if (real_module.empty()) {
+    return program->get_name() + "_";
+  }
+  return real_module + "_";
+}
+
+string t_lua_generator::function_signature(t_function* tfunction,
+                                           string prefix) {
+  std::string ret = tfunction->get_name() + "(" +
+    argument_list(tfunction->get_arglist()) + ")";
+  return ret;
+}
+
+string t_lua_generator::argument_list(t_struct* tstruct, string prefix) {
+  const vector<t_field*>& fields = tstruct->get_members();
+  vector<t_field*>::const_iterator fld_iter;
+  std::string ret = "";
+  for (fld_iter = fields.begin(); fld_iter != fields.end();) {
+    ret += prefix + (*fld_iter)->get_name();
+    ++fld_iter;
+    if (fld_iter != fields.end()) {
+      ret += ", ";
+    }
+  }
+  return ret;
+}
+
+string t_lua_generator::type_to_enum(t_type* type) {
+  type = get_true_type(type);
+
+  if (type->is_base_type()) {
+    t_base_type::t_base tbase = ((t_base_type*)type)->get_base();
+    switch (tbase) {
+      case t_base_type::TYPE_VOID:
+        throw "NO T_VOID CONSTRUCT";
+      case t_base_type::TYPE_STRING:
+        return "TType.STRING";
+      case t_base_type::TYPE_BOOL:
+        return "TType.BOOL";
+      case t_base_type::TYPE_BYTE:
+        return "TType.BYTE";
+      case t_base_type::TYPE_I16:
+        return "TType.I16";
+      case t_base_type::TYPE_I32:
+        return "TType.I32";
+      case t_base_type::TYPE_I64:
+        return "TType.I64";
+      case t_base_type::TYPE_DOUBLE:
+        return "TType.DOUBLE";
+    }
+  } else if (type->is_enum()) {
+    return "TType.I32";
+  } else if (type->is_struct() || type->is_xception()) {
+    return "TType.STRUCT";
+  } else if (type->is_map()) {
+    return "TType.MAP";
+  } else if (type->is_set()) {
+    return "TType.SET";
+  } else if (type->is_list()) {
+    return "TType.LIST";
+  }
+
+  throw "INVALID TYPE IN type_to_enum: " + type->get_name();
+}
+
+THRIFT_REGISTER_GENERATOR(lua, "Lua", "");