handles unknown field in json body while deserializing

aws · Jun 1, 2020 · 60c29a0 · 60c29a0
1 parent 4348d9a
commit 60c29a0
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Showing 2 changed files with 36 additions and 16 deletions.
diff --git a/aws/protocol/json/decoder_util.go b/aws/protocol/json/decoder_util.go
@@ -56,10 +56,8 @@ func GetErrorInfo(decoder *json.Decoder) (string, string, error) {
 			typeCode = v.(string)
 			break
 		default:
-			for decoder.More() {
-				// discard tokens for unknown field
-				decoder.Token()
-			}
+			DiscardUnknownField(decoder)
+			break
 		}
 	}
 
@@ -94,3 +92,17 @@ func SanitizeErrorCode(errorCode string) string {
 
 	return errorCode
 }
+
+
+// DiscardUnknownField discards unknown fields from decoder body.
+// This function is useful while deserializing json body with additional
+// unknown information that should be discarded.
+func DiscardUnknownField(decoder *json.Decoder) {
+	v, _ := decoder.Token()
+	if _, ok := v.(json.Delim); ok {
+		for decoder.More() {
+			DiscardUnknownField(decoder)
+		}
+		decoder.Token()
+	}
+}
diff --git a/...odegen/src/main/java/software/amazon/smithy/aws/go/codegen/RestJsonProtocolGenerator.java b/...odegen/src/main/java/software/amazon/smithy/aws/go/codegen/RestJsonProtocolGenerator.java
@@ -818,20 +818,27 @@ private void generateDocumentBindingStructureShapeDeserializer(
                 () -> {
                     writer.write("t, err := decoder.Token()");
                     writer.write("if err != nil { return err }");
-                    for (MemberShape memberShape : shape.members()) {
-                        if (!filterMemberShapes.test(memberShape)) {
-                            continue;
+                    writer.openBlock("switch t {", "}", () -> {
+                        for (MemberShape memberShape : shape.members()) {
+                            if (!filterMemberShapes.test(memberShape)) {
+                                continue;
+                            }
+
+                            String memberName = symbolProvider.toMemberName(memberShape);
+                            writer.openBlock("case $S :", "", memberShape.getMemberName(), () -> {
+                                        String operand = generateDocumentBindingMemberShapeDeserializer(writer, model, symbolProvider, memberShape);
+                                        writer.write(String.format("v.%s = %s", memberName, operand));
+                                        writer.write("break");
+                                    });
                         }
 
-                        String memberName = symbolProvider.toMemberName(memberShape);
-                        writer.write("");
-                        writer.openBlock("if t == $S {", "}",
-                                memberShape.getMemberName(), () -> {
-                                    String operand = generateDocumentBindingMemberShapeDeserializer(
-                                            writer, model, symbolProvider, memberShape);
-                                    writer.write(String.format("v.%s = %s", memberName, operand));
-                                });
-                    }
+                        // default case to handle unknown fields
+                        writer.openBlock("default : ","", () -> {
+                            writer.addUseImports(GoDependency.AWS_JSON_PROTOCOL_ALIAS);
+                            writer.write("jsonprotocol.DiscardUnknownField(decoder)");
+                            writer.write("break");
+                        });
+                    });
                 });
         writeJsonTokenizerEndStub(writer, shape);
     }
@@ -1124,6 +1131,7 @@ private void writeJsonTokenizerEndStub(GoWriter writer, Shape shape) {
                 });
     }
 
+
     @Override
     public void generateSharedDeserializerComponents(GenerationContext context) {
         super.generateSharedDeserializerComponents(context);