protogen: Unmarshal stringified integers from JSON

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>

util/protogen/internalgengo/json.go

@@ -74,6 +74,17 @@ func emitJSONFieldRead(g *protogen.GeneratedFile, f *protogen.Field, name string
 		g.P("var f ", fieldType(g, f))
 	}
 
+	parseInteger := func(ident string, method string, bitSize int, typ string) {
+		g.P("r := in.JsonNumber()")
+		g.P("n := r.String()")
+		g.P("v, err := ", strconvPackage.Ident(method), "(n, 10, ", bitSize, ")")
+		g.P("if err != nil {")
+		g.P("	in.AddError(err)")
+		g.P("	return")
+		g.P("}")
+		g.P(ident, " := ", typ, "(v)")
+	}
+
 	var template string
 	switch f.Desc.Kind() {
 	case protoreflect.BoolKind:
@@ -100,13 +111,17 @@ func emitJSONFieldRead(g *protogen.GeneratedFile, f *protogen.Field, name string
 		}`)
 		template = "%s = parsedValue"
 	case protoreflect.Int32Kind, protoreflect.Sint32Kind, protoreflect.Sfixed32Kind:
-		template = "%s = in.Int32()"
+		parseInteger("pv", "ParseInt", 32, "int32")
+		template = "%s = pv"
 	case protoreflect.Uint32Kind, protoreflect.Fixed32Kind:
-		template = "%s = in.Uint32()"
+		parseInteger("pv", "ParseUint", 32, "uint32")
+		template = "%s = pv"
 	case protoreflect.Int64Kind, protoreflect.Sint64Kind, protoreflect.Sfixed64Kind:
-		template = "%s = in.Int64()"
+		parseInteger("pv", "ParseInt", 64, "int64")
+		template = "%s = pv"
 	case protoreflect.Uint64Kind, protoreflect.Fixed64Kind:
-		template = "%s = in.Uint64()"
+		parseInteger("pv", "ParseUint", 64, "uint64")
+		template = "%s = pv"
 	case protoreflect.FloatKind:
 		template = "%s = in.Float32()"
 	case protoreflect.DoubleKind: