fix(parser): Unmarshalling of resources with polymorphic properties (…

…like S3 events) now works (awslabs#188)

cloudformation/resources/aws-serverless-function_dynamodbevent.go

@@ -7,9 +7,9 @@ import "github.com/awslabs/goformation/cloudformation/policies"
 type AWSServerlessFunction_DynamoDBEvent struct {
 
 	// BatchSize AWS CloudFormation Property
-	// Required: true
+	// Required: false
 	// See: https://github.com/awslabs/serverless-application-model/blob/master/versions/2016-10-31.md#dynamodb
-	BatchSize int `json:"BatchSize"`
+	BatchSize int `json:"BatchSize,omitempty"`
 
 	// StartingPosition AWS CloudFormation Property
 	// Required: true

cloudformation/resources/awsserverlessapi_definitionuri.go

@@ -4,8 +4,6 @@ import (
 	"sort"
 
 	"encoding/json"
-
-	"github.com/mitchellh/mapstructure"
 )
 
 // AWSServerlessApi_DefinitionUri is a helper struct that can hold either a String or S3Location value
@@ -55,8 +53,9 @@ func (r *AWSServerlessApi_DefinitionUri) UnmarshalJSON(b []byte) error {
 		r.String = &val
 
 	case map[string]interface{}:
+		val = val // This ensures val is used to stop an error
 
-		mapstructure.Decode(val, &r.S3Location)
+		json.Unmarshal(b, &r.S3Location)
 
 	case []interface{}:
 

cloudformation/resources/awsserverlessapplication_location.go

@@ -4,8 +4,6 @@ import (
 	"sort"
 
 	"encoding/json"
-
-	"github.com/mitchellh/mapstructure"
 )
 
 // AWSServerlessApplication_Location is a helper struct that can hold either a String or ApplicationLocation value
@@ -55,8 +53,9 @@ func (r *AWSServerlessApplication_Location) UnmarshalJSON(b []byte) error {
 		r.String = &val
 
 	case map[string]interface{}:
+		val = val // This ensures val is used to stop an error
 
-		mapstructure.Decode(val, &r.ApplicationLocation)
+		json.Unmarshal(b, &r.ApplicationLocation)
 
 	case []interface{}:
 

cloudformation/resources/awsserverlessfunction_codeuri.go

@@ -4,8 +4,6 @@ import (
 	"sort"
 
 	"encoding/json"
-
-	"github.com/mitchellh/mapstructure"
 )
 
 // AWSServerlessFunction_CodeUri is a helper struct that can hold either a String or S3Location value
@@ -55,8 +53,9 @@ func (r *AWSServerlessFunction_CodeUri) UnmarshalJSON(b []byte) error {
 		r.String = &val
 
 	case map[string]interface{}:
+		val = val // This ensures val is used to stop an error
 
-		mapstructure.Decode(val, &r.S3Location)
+		json.Unmarshal(b, &r.S3Location)
 
 	case []interface{}:
 

cloudformation/resources/awsserverlessfunction_events.go

@@ -2,8 +2,6 @@ package resources
 
 import (
 	"encoding/json"
-
-	"github.com/mitchellh/mapstructure"
 )
 
 // AWSServerlessFunction_Events is a helper struct that can hold either a String or String value
@@ -49,10 +47,11 @@ func (r *AWSServerlessFunction_Events) UnmarshalJSON(b []byte) error {
 		r.StringArray = &val
 
 	case map[string]interface{}:
+		val = val // This ensures val is used to stop an error
 
 	case []interface{}:
 
-		mapstructure.Decode(val, &r.StringArray)
+		json.Unmarshal(b, &r.StringArray)
 
 	}
 

cloudformation/resources/awsserverlessfunction_policies.go

@@ -4,8 +4,6 @@ import (
 	"sort"
 
 	"encoding/json"
-
-	"github.com/mitchellh/mapstructure"
 )
 
 // AWSServerlessFunction_Policies is a helper struct that can hold either a String, String, IAMPolicyDocument, or IAMPolicyDocument value
@@ -70,14 +68,15 @@ func (r *AWSServerlessFunction_Policies) UnmarshalJSON(b []byte) error {
 		r.StringArray = &val
 
 	case map[string]interface{}:
+		val = val // This ensures val is used to stop an error
 
-		mapstructure.Decode(val, &r.IAMPolicyDocument)
+		json.Unmarshal(b, &r.IAMPolicyDocument)
 
 	case []interface{}:
 
-		mapstructure.Decode(val, &r.StringArray)
+		json.Unmarshal(b, &r.StringArray)
 
-		mapstructure.Decode(val, &r.IAMPolicyDocumentArray)
+		json.Unmarshal(b, &r.IAMPolicyDocumentArray)
 
 	}
 

cloudformation/resources/awsserverlessfunction_properties.go

@@ -4,8 +4,6 @@ import (
 	"sort"
 
 	"encoding/json"
-
-	"github.com/mitchellh/mapstructure"
 )
 
 // AWSServerlessFunction_Properties is a helper struct that can hold either a S3Event, SNSEvent, SQSEvent, KinesisEvent, DynamoDBEvent, ApiEvent, ScheduleEvent, CloudWatchEventEvent, IoTRuleEvent, or AlexaSkillEvent value
@@ -91,26 +89,27 @@ func (r *AWSServerlessFunction_Properties) UnmarshalJSON(b []byte) error {
 	switch val := typecheck.(type) {
 
 	case map[string]interface{}:
+		val = val // This ensures val is used to stop an error
 
-		mapstructure.Decode(val, &r.S3Event)
+		json.Unmarshal(b, &r.S3Event)
 
-		mapstructure.Decode(val, &r.SNSEvent)
+		json.Unmarshal(b, &r.SNSEvent)
 
-		mapstructure.Decode(val, &r.SQSEvent)
+		json.Unmarshal(b, &r.SQSEvent)
 
-		mapstructure.Decode(val, &r.KinesisEvent)
+		json.Unmarshal(b, &r.KinesisEvent)
 
-		mapstructure.Decode(val, &r.DynamoDBEvent)
+		json.Unmarshal(b, &r.DynamoDBEvent)
 
-		mapstructure.Decode(val, &r.ApiEvent)
+		json.Unmarshal(b, &r.ApiEvent)
 
-		mapstructure.Decode(val, &r.ScheduleEvent)
+		json.Unmarshal(b, &r.ScheduleEvent)
 
-		mapstructure.Decode(val, &r.CloudWatchEventEvent)
+		json.Unmarshal(b, &r.CloudWatchEventEvent)
 
-		mapstructure.Decode(val, &r.IoTRuleEvent)
+		json.Unmarshal(b, &r.IoTRuleEvent)
 
-		mapstructure.Decode(val, &r.AlexaSkillEvent)
+		json.Unmarshal(b, &r.AlexaSkillEvent)
 
 	case []interface{}:
 

generate/property_test.go

@@ -68,6 +68,22 @@ var _ = Describe("Goformation Code Generator", func() {
 
 			})
 
+			Context("properly marshals and unmarshals polymorphic values", func() {
+
+				property := []byte(`{"Properties":{"Bucket":"asd","Events":"LATEST"},"Type":"S3"}`)
+
+				result := &resources.AWSServerlessFunction_EventSource{}
+				err := json.Unmarshal(property, result)
+				output, err2 := json.Marshal(result)
+
+				It("should marshal and unmarhal to same value", func() {
+					Expect(err).To(BeNil())
+					Expect(err2).To(BeNil())
+					Expect(output).To(Equal(property))
+				})
+
+			})
+
 			Context("properly Marshals best value", func() {
 				expected := []byte(`{"BatchSize":10,"Stream":"arn"}`)
 

generate/sam-2016-10-31.json

@@ -506,7 +506,7 @@
                 },
                 "BatchSize": {
                     "Documentation": "https://github.com/awslabs/serverless-application-model/blob/master/versions/2016-10-31.md#dynamodb",
-                    "Required": true,
+                    "Required": false,
                     "PrimitiveType": "Integer",
                     "UpdateType": "Immutable"
                 }

generate/templates/polymorphic-property.template

@@ -5,9 +5,6 @@ import (
 	"sort"
 	{{end}}
 	"encoding/json"
-	{{ if (or .Property.Types .Property.ItemTypes .Property.PrimitiveItemTypes)}}
-	"github.com/mitchellh/mapstructure"
-	{{end}}
 )
 
 // {{.Name}} is a helper struct that can hold either a {{.TypesJoined}} value
@@ -88,16 +85,17 @@ func (r *{{.Name}}) UnmarshalJSON(b []byte) error {
 		{{end}}
 
 		case map[string]interface{}:
+			val = val // This ensures val is used to stop an error
 		{{range $type := $.Property.Types}}
-			mapstructure.Decode(val, &r.{{$type}})
+			json.Unmarshal(b, &r.{{$type}})
 		{{end}}
 
 		case []interface{}:
 		{{range $type := $.Property.PrimitiveItemTypes}}
-			mapstructure.Decode(val, &r.{{$type}}Array)
+			json.Unmarshal(b, &r.{{$type}}Array)
 		{{end}}
 		{{range $type := $.Property.ItemTypes}}
-			mapstructure.Decode(val, &r.{{$type}}Array)
+			json.Unmarshal(b, &r.{{$type}}Array)
 		{{end}}
 
 	}

go.sum

@@ -9,8 +9,6 @@ github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORN
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
-github.com/mitchellh/mapstructure v1.1.0 h1:PoCJ/Ct9du6caE+91v8ov4CLjO4XEBgkPk/dF1v43eo=
-github.com/mitchellh/mapstructure v1.1.0/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/mitchellh/mapstructure v1.1.2 h1:fmNYVwqnSfB9mZU6OS2O6GsXM+wcskZDuKQzvN1EDeE=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/onsi/ginkgo v1.5.0 h1:uZr+v/TFDdYkdA+j02sPO1kA5owrfjBGCJAogfIyThE=

schema/sam.go

@@ -40274,7 +40274,6 @@ var SamSchema = `{
                 }
             },
             "required": [
-                "BatchSize",
                 "StartingPosition",
                 "Stream"
             ],

schema/sam.schema.json

@@ -40271,7 +40271,6 @@
                 }
             },
             "required": [
-                "BatchSize",
                 "StartingPosition",
                 "Stream"
             ],