Generate Mojom Types in Go

mojo/public/tools/bindings/generators/mojom_go_generator.py

Index: mojo/public/tools/bindings/generators/mojom_go_generator.py
diff --git a/mojo/public/tools/bindings/generators/mojom_go_generator.py b/mojo/public/tools/bindings/generators/mojom_go_generator.py
index 7b1c7ac8920cce3fc3d6ca2834880a4a8f1aa672..1443665294dc464d09f2926f894d656c24a25a4b 100644
--- a/mojo/public/tools/bindings/generators/mojom_go_generator.py
+++ b/mojo/public/tools/bindings/generators/mojom_go_generator.py
@@ -5,6 +5,7 @@
 '''Generates Go source files from a mojom.Module.'''
 
 from itertools import chain
+import base64
 import os
 import re
 
@@ -15,50 +16,62 @@ import mojom.generate.module as mojom
 import mojom.generate.pack as pack
 
 class KindInfo(object):
-  def __init__(self, go_type, encode_suffix, decode_suffix, bit_size):
+  def __init__(self, go_type, encode_suffix, decode_suffix, bit_size, type_template):

[azani, 2015/10/12 21:13:08]

Can you construct the type_template programmatically in GetMojomTypeValue
instead? That will make it easier to change in the future.

[alexfandrianto, 2015/10/16 21:25:49]

Done.

     self.go_type = go_type
     self.encode_suffix = encode_suffix
     self.decode_suffix = decode_suffix
     self.bit_size = bit_size
+    self.type_template = type_template
 
 _kind_infos = {
-  mojom.BOOL:                  KindInfo('bool', 'Bool', 'Bool', 1),
-  mojom.INT8:                  KindInfo('int8', 'Int8', 'Int8', 8),
-  mojom.UINT8:                 KindInfo('uint8', 'Uint8', 'Uint8', 8),
-  mojom.INT16:                 KindInfo('int16', 'Int16', 'Int16', 16),
-  mojom.UINT16:                KindInfo('uint16', 'Uint16', 'Uint16', 16),
-  mojom.INT32:                 KindInfo('int32', 'Int32', 'Int32', 32),
-  mojom.UINT32:                KindInfo('uint32', 'Uint32', 'Uint32', 32),
-  mojom.FLOAT:                 KindInfo('float32', 'Float32', 'Float32', 32),
+  mojom.BOOL:                  KindInfo('bool', 'Bool', 'Bool', 1, '%sTypeSimpleType{%sSimpleType_Bool}'),
+  mojom.INT8:                  KindInfo('int8', 'Int8', 'Int8', 8, '%sTypeSimpleType{%sSimpleType_InT8}'),
+  mojom.UINT8:                 KindInfo('uint8', 'Uint8', 'Uint8', 8, '%sTypeSimpleType{%sSimpleType_UinT8}'),
+  mojom.INT16:                 KindInfo('int16', 'Int16', 'Int16', 16, '%sTypeSimpleType{%sSimpleType_InT16}'),
+  mojom.UINT16:                KindInfo('uint16', 'Uint16', 'Uint16', 16, '%sTypeSimpleType{%sSimpleType_UinT16}'),
+  mojom.INT32:                 KindInfo('int32', 'Int32', 'Int32', 32, '%sTypeSimpleType{%sSimpleType_InT32}'),
+  mojom.UINT32:                KindInfo('uint32', 'Uint32', 'Uint32', 32, '%sTypeSimpleType{%sSimpleType_UinT32}'),
+  mojom.FLOAT:                 KindInfo('float32', 'Float32', 'Float32', 32, '%sTypeSimpleType{%sSimpleType_Float}'),
   mojom.HANDLE:                KindInfo(
-      'system.Handle', 'Handle', 'Handle', 32),
+      'system.Handle', 'Handle', 'Handle', 32, '%sTypeHandleType{%sHandleType{Nullable: false, Kind: %sHandleType_Kind_Unspecified}}'),
   mojom.DCPIPE:                KindInfo(
-      'system.ConsumerHandle', 'Handle', 'ConsumerHandle', 32),
+      'system.ConsumerHandle', 'Handle', 'ConsumerHandle', 32, '%sTypeHandleType{%sHandleType{Nullable: false, Kind: %sHandleType_Kind_DataPipeConsumer}}'),
   mojom.DPPIPE:                KindInfo(
-      'system.ProducerHandle', 'Handle', 'ProducerHandle', 32),
+      'system.ProducerHandle', 'Handle', 'ProducerHandle', 32, '%sTypeHandleType{%sHandleType{Nullable: false, Kind: %sHandleType_Kind_DataPipeProducer}}'),
   mojom.MSGPIPE:               KindInfo(
-      'system.MessagePipeHandle', 'Handle', 'MessagePipeHandle', 32),
+      'system.MessagePipeHandle', 'Handle', 'MessagePipeHandle', 32, '%sTypeHandleType{%sHandleType{Nullable: false, Kind: %sHandleType_Kind_MessagePipe}}'),
   mojom.SHAREDBUFFER:          KindInfo(
-      'system.SharedBufferHandle', 'Handle', 'SharedBufferHandle', 32),
+      'system.SharedBufferHandle', 'Handle', 'SharedBufferHandle', 32, '%sTypeHandleType{%sHandleType{Nullable: false, Kind: %sHandleType_Kind_SharedBuffer}}'),
   mojom.NULLABLE_HANDLE:       KindInfo(
-      'system.Handle', 'Handle', 'Handle', 32),
+      'system.Handle', 'Handle', 'Handle', 32, '%sTypeHandleType{%sHandleType{Nullable: true, Kind: %sHandleType_Kind_Unspecified}}'),
   mojom.NULLABLE_DCPIPE:       KindInfo(
-      'system.ConsumerHandle', 'Handle', 'ConsumerHandle', 32),
+      'system.ConsumerHandle', 'Handle', 'ConsumerHandle', 32, '%sTypeHandleType{%sHandleType{Nullable: true, Kind: %sHandleType_Kind_DataPipeConsumer}}'),
   mojom.NULLABLE_DPPIPE:       KindInfo(
-      'system.ProducerHandle', 'Handle', 'ProducerHandle', 32),
+      'system.ProducerHandle', 'Handle', 'ProducerHandle', 32, '%sTypeHandleType{%sHandleType{Nullable: true, Kind: %sHandleType_Kind_DataPipeProducer}}'),
   mojom.NULLABLE_MSGPIPE:      KindInfo(
-      'system.MessagePipeHandle', 'Handle', 'MessagePipeHandle', 32),
+      'system.MessagePipeHandle', 'Handle', 'MessagePipeHandle', 32, '%sTypeHandleType{%sHandleType{Nullable: true, Kind: %sHandleType_Kind_MessagePipe}}'),
   mojom.NULLABLE_SHAREDBUFFER: KindInfo(
-      'system.SharedBufferHandle', 'Handle', 'SharedBufferHandle', 32),
-  mojom.INT64:                 KindInfo('int64', 'Int64', 'Int64', 64),
-  mojom.UINT64:                KindInfo('uint64', 'Uint64', 'Uint64', 64),
-  mojom.DOUBLE:                KindInfo('float64', 'Float64', 'Float64', 64),
-  mojom.STRING:                KindInfo('string', 'String', 'String', 64),
-  mojom.NULLABLE_STRING:       KindInfo('string', 'String', 'String', 64),
+      'system.SharedBufferHandle', 'Handle', 'SharedBufferHandle', 32, '%sTypeHandleType{%sHandleType{Nullable: true, Kind: %sHandleType_Kind_SharedBuffer}}'),
+  mojom.INT64:                 KindInfo('int64', 'Int64', 'Int64', 64, '%sTypeSimpleType{%sSimpleType_InT64}'),
+  mojom.UINT64:                KindInfo('uint64', 'Uint64', 'Uint64', 64, '%sTypeSimpleType{%sSimpleType_UinT64}'),
+  mojom.DOUBLE:                KindInfo('float64', 'Float64', 'Float64', 64, '%sTypeSimpleType{%sSimpleType_Double}'),
+  mojom.STRING:                KindInfo('string', 'String', 'String', 64, '%sTypeStringType{%sStringType{false}}'),
+  mojom.NULLABLE_STRING:       KindInfo('string', 'String', 'String', 64, '%sTypeStringType{%sStringType{true}}'),
 }
 
+# _imports keeps track of the imports that the .go.mojom file needs to import.
 _imports = {}
 
+# _mojom_imports keeps a list of the other .mojom files imported by this one.
+_mojom_imports = {}
+
+# The mojom_types.mojom and service_describer.mojom files are special because
+# they are used to generate mojom Type's and ServiceDescription implementations.
+_service_describer_pkg = "mojo/public/interfaces/bindings/service_describer"

[azani, 2015/10/12 21:13:07]

Maybe do:
_service_describer_pkg_short = "service_describer"
_service_describer_pkg = "mojo/public/interfaces/bindings/%s" %
_service_describer_pkg_short

[alexfandrianto, 2015/10/16 21:25:49]

Done.

+_service_describer_pkg_short = "service_describer"
+_mojom_types_pkg = "mojo/public/interfaces/bindings/mojom_types"
+_mojom_types_pkg_short = "mojom_types"
+
 def GetBitSize(kind):
   if isinstance(kind, (mojom.Union)):
     return 128
@@ -186,18 +199,27 @@ def EncodeSuffix(kind):
     return EncodeSuffix(mojom.MSGPIPE)
   return _kind_infos[kind].encode_suffix
 
+# This helper assists in the production of mojom_types.Type for simple kinds.
+# See _kind_infos above.
+def GetMojomTypeValue(kind, typepkg=''):
+  if not kind in _kind_infos:
+    return ''
+  if mojom.IsAnyHandleKind(kind):
+    return _kind_infos[kind].type_template % (typepkg, typepkg, typepkg)
+  return _kind_infos[kind].type_template % (typepkg, typepkg)
+
 def GetPackageName(module):
   return module.name.split('.')[0]
 
-def GetPackageNameForElement(element):
+def GetPackageNameForElement(element, default=''):
   if not hasattr(element, 'imported_from') or not element.imported_from:
-    return ''
+    return default
   path = ''
   if element.imported_from['module'].path:
     path += GetPackagePath(element.imported_from['module'])
   if path in _imports:
     return _imports[path]
-  return ''
+  return default
 
 def GetQualifiedName(name, package=None, exported=True):
   if not package:
@@ -220,6 +242,7 @@ def GetAllEnums(module):
 
 # Adds an import required to use the provided |element|.
 # The required import is stored at '_imports'.
+# The mojom imports are also stored separately in '_mojom_imports'.
 def AddImport(module, element):
   if not isinstance(element, mojom.Kind):
     return
@@ -244,10 +267,34 @@ def AddImport(module, element):
   if path in _imports:
     return
   name = GetPackageName(imported['module'])
-  while name in _imports.values():
+  while name in _imports.values(): # This avoids repeated names.
     name += '_'
   _imports[path] = name
+  _mojom_imports[path] = name
+
+# The identifier cache is used by the Type generator to determine if a type has
+# already been generated or not. This prevents over-generation of the same type
+# when it is referred to in multiple ways.
+identifier_cache = {}
+def GetIdentifier(kind, default):
+  package = GetPackageNameForElement(kind, default)
+
+  # Most kinds have a name, but those that don't should rely on their spec.
+  # Since spec can have : and ? characters, these must be replaced. Since ? is
+  # replaced with '', the caller must keep track of optionality on its own.
+  package_unique = (kind.name if hasattr(kind, 'name') else kind.spec).replace(':', '_').replace('?', '')
+  return '%s_%s' % (package, package_unique)
+
+def StoreIdentifier(identifier, cache_name):
+  if not cache_name in identifier_cache:
+    identifier_cache[cache_name] = {}
+  identifier_cache[cache_name][identifier] = True
+  return ''
 
+def CheckIdentifier(identifier, cache_name):
+  if not cache_name in identifier_cache:
+    identifier_cache[cache_name] = {}
+  return identifier in identifier_cache[cache_name]
 
 class Generator(generator.Generator):
   go_filters = {
@@ -258,6 +305,9 @@ class Generator(generator.Generator):
     'go_type': GetGoType,
     'expression_to_text': ExpressionToText,
     'has_response': lambda method: method.response_parameters is not None,
+    'identifier': GetIdentifier,
+    'identifier_check': CheckIdentifier,
+    'identifier_store': StoreIdentifier,
     'is_array': mojom.IsArrayKind,
     'is_enum': mojom.IsEnumKind,
     'is_handle': mojom.IsAnyHandleKind,
@@ -271,6 +321,7 @@ class Generator(generator.Generator):
     'is_struct': mojom.IsStructKind,
     'is_union': mojom.IsUnionKind,
     'qualified': GetQualifiedName,
+    'mojom_type': GetMojomTypeValue,
     'name': GetNameForElement,
     'unqualified_name': GetUnqualifiedNameForElement,
     'package': GetPackageNameForElement,
@@ -278,13 +329,17 @@ class Generator(generator.Generator):
   }
 
   def GetParameters(self):
+    package = GetPackageName(self.module)
     return {
       'enums': GetAllEnums(self.module),
       'imports': self.GetImports(),
       'interfaces': self.GetInterfaces(),
-      'package': GetPackageName(self.module),
+      'mojom_imports': self.GetMojomImports(),
+      'package': package,
       'structs': self.GetStructs(),
-      'unions': self.GetUnions(),
+      'descpkg': '%s.' % _service_describer_pkg_short if package != _service_describer_pkg_short else '',
+      'typepkg': '%s.' % _mojom_types_pkg_short if package != _mojom_types_pkg_short else '',
+      'unions': self.GetUnions()
     }
 
   @UseJinja('go_templates/source.tmpl', filters=go_filters)
@@ -344,6 +399,17 @@ class Generator(generator.Generator):
         if field.value:
           AddImport(self.module, field.value)
 
+    num_user_defined_types = len(self.module.interfaces) + \
+      len(self.module.unions) + len(all_structs) + len(GetAllEnums(self.module))
+    if num_user_defined_types > 0 \
+      and GetPackageName(self.module) != _mojom_types_pkg_short:
+        _imports[_mojom_types_pkg] = _mojom_types_pkg_short
+
+    if len(self.module.interfaces) > 0 \
+      and GetPackageName(self.module) != _mojom_types_pkg_short \
+      and GetPackageName(self.module) != _service_describer_pkg_short:
+      _imports[_service_describer_pkg] = _service_describer_pkg_short
+
 # TODO(rogulenko): add these after generating constants and struct defaults.
 #    for constant in GetAllConstants(self.module):
 #      AddImport(self.module, constant.value)
@@ -356,6 +422,11 @@ class Generator(generator.Generator):
         imports_list.append('%s "%s"' % (_imports[i], i))
     return sorted(imports_list)
 
+  def GetMojomImports(self):

[azani, 2015/10/12 21:13:07]

Instead, change GetImports to return a tuple of its current output and
_mojom_imports and then write two methods that return the first and second
entries respectively. (or just call the method twice with the proper index.)

[alexfandrianto, 2015/10/16 21:25:49]

Done.

+    # GetImports (idempotent) prepares the _imports and _mojom_imports maps.
+    self.GetImports()
+    return _mojom_imports
+
   # Overrides the implementation from the base class in order to customize the
   # struct and field names.
   def _GetStructFromMethod(self, method):