JavaScript bindings for Mojo message validation

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

Index: mojo/public/tools/bindings/generators/mojom_js_generator.py
diff --git a/mojo/public/tools/bindings/generators/mojom_js_generator.py b/mojo/public/tools/bindings/generators/mojom_js_generator.py
index 5b83974d97943ec15a117e877cd978bef32a1c73..51b1012a53b703c6fe46eda843f54f601cc9b622 100644
--- a/mojo/public/tools/bindings/generators/mojom_js_generator.py
+++ b/mojo/public/tools/bindings/generators/mojom_js_generator.py
@@ -97,9 +97,9 @@ def CodecType(kind):
     return _kind_to_codec_type[kind]
   if mojom.IsStructKind(kind):
     return "new codec.PointerTo(%s)" % CodecType(kind.name)
-  if mojom.IsArrayKind(kind) and mojom.IsBoolKind(kind.kind):
-    return "new codec.ArrayOf(new codec.ArrayOf(codec.PackedBool))"
-  if mojom.IsArrayKind(kind):
+  if mojom.IsAnyArrayKind(kind) and mojom.IsBoolKind(kind.kind):
+    return "new codec.ArrayOf(codec.PackedBool)"
+  if mojom.IsAnyArrayKind(kind):
     return "new codec.ArrayOf(%s)" % CodecType(kind.kind)
   if mojom.IsInterfaceKind(kind) or mojom.IsInterfaceRequestKind(kind):
     return CodecType(mojom.MSGPIPE)
@@ -113,9 +113,9 @@ def JavaScriptDecodeSnippet(kind):
     return "decodeStruct(%s)" % CodecType(kind)
   if mojom.IsStructKind(kind):
     return "decodeStructPointer(%s)" % CodecType(kind.name)
-  if mojom.IsArrayKind(kind) and mojom.IsBoolKind(kind.kind):
-    return "decodeArrayPointer(new codec.ArrayOf(codec.PackedBool))"
-  if mojom.IsArrayKind(kind):
+  if mojom.IsAnyArrayKind(kind) and mojom.IsBoolKind(kind.kind):
+    return "decodeArrayPointer(codec.PackedBool)"
+  if mojom.IsAnyArrayKind(kind):
     return "decodeArrayPointer(%s)" % CodecType(kind.kind)
   if mojom.IsInterfaceKind(kind) or mojom.IsInterfaceRequestKind(kind):
     return JavaScriptDecodeSnippet(mojom.MSGPIPE)
@@ -128,8 +128,8 @@ def JavaScriptEncodeSnippet(kind):
     return "encodeStruct(%s, " % CodecType(kind)
   if mojom.IsStructKind(kind):
     return "encodeStructPointer(%s, " % CodecType(kind.name)
-  if mojom.IsArrayKind(kind) and mojom.IsBoolKind(kind.kind):
-    return "encodeArrayPointer(new codec.ArrayOf(codec.PackedBool), ";
+  if mojom.IsAnyArrayKind(kind) and mojom.IsBoolKind(kind.kind):
+    return "encodeArrayPointer(codec.PackedBool, ";
   if mojom.IsAnyArrayKind(kind):
     return "encodeArrayPointer(%s, " % CodecType(kind.kind)
   if mojom.IsInterfaceKind(kind) or mojom.IsInterfaceRequestKind(kind):
@@ -138,6 +138,22 @@ def JavaScriptEncodeSnippet(kind):
     return JavaScriptEncodeSnippet(mojom.INT32)
 
 
+def JavaScriptFieldOffset(packed_field):
+  return "offset + codec.kStructHeaderSize + %s" % packed_field.offset
+
+def JavaScriptValidateArrayParams(pf):
+  elementKind = pf.field.kind.kind
+  elementSize = pack.PackedField.GetSizeForKind(elementKind)
+  elementCount = generator.ExpectedArraySize(pf.field.kind)
+  elementType = "codec.PackedBool" if mojom.IsBoolKind(elementKind) \
+      else CodecType(elementKind)
+  return "%s, %s, %s, %s" % \
+    (JavaScriptFieldOffset(pf), elementSize, elementCount, elementType)
+
+def JavaScriptValidateStructParams(pf):
+  return "%s, %s" % (JavaScriptFieldOffset(pf), pf.field.kind.name)
+
+
 def TranslateConstants(token):
   if isinstance(token, (mojom.EnumValue, mojom.NamedValue)):
     # Both variable and enum constants are constructed like:
@@ -164,6 +180,25 @@ def JavascriptType(kind):
   return kind.name
 
 
+def HasCallbacks(interface):

[yzshen1, 2014/08/14 18:02:22]

Shall we move this method into generator.py so that both mojom_cpp_generator and
mojom_js_generate can use it?

[hansmuller, 2014/08/14 23:51:46]

Yes. I moved it into module.py, since the Interface class is defined there. The
C++ bindings generator now uses it as well.

+  for method in interface.methods:
+    if method.response_parameters != None:
+      return True
+  return False
+
+def IsArrayPointerField(field):

[yzshen1, 2014/08/14 18:02:22]

[optional] If you want, you could consider directly export mojom.IsXXXKind() in
js_filters. The consequence is that you need to do field.kind|is_any_array_kind,
for example. But you don't need to define these one-line functions.

[hansmuller, 2014/08/14 23:51:46]

That's a reasonable suggestion however if you don't mind I will leave  this
particular detail alone for the moment. I liked the fact that the both the test,
like is_struct_pointer_field, and the corresponding method parameter generate,
like validate_struct_params, both just applied to the field object.

[yzshen1, 2014/08/15 16:26:36]

Acknowledged.

+  return mojom.IsAnyArrayKind(field.kind)
+
+def IsStringPointerField(field):
+  return mojom.IsStringKind(field.kind)
+
+def IsStructPointerField(field):
+  return mojom.IsStructKind(field.kind)
+
+def IsHandleField(field):
+  return mojom.IsAnyHandleKind(field.kind)
+
+
 class Generator(generator.Generator):
 
   js_filters = {
@@ -172,8 +207,16 @@ class Generator(generator.Generator):
     "decode_snippet": JavaScriptDecodeSnippet,
     "encode_snippet": JavaScriptEncodeSnippet,
     "expression_to_text": ExpressionToText,
+    "field_offset": JavaScriptFieldOffset,
+    "has_callbacks": HasCallbacks,
+    "is_array_pointer_field": IsArrayPointerField,
+    "is_struct_pointer_field": IsStructPointerField,
+    "is_string_pointer_field": IsStringPointerField,
+    "is_handle_field": IsHandleField,
     "js_type": JavascriptType,
     "stylize_method": generator.StudlyCapsToCamel,
+    "validate_array_params": JavaScriptValidateArrayParams,
+    "validate_struct_params": JavaScriptValidateStructParams,
   }
 
   @UseJinja("js_templates/module.js.tmpl", filters=js_filters)