Add support for structured value type

go.mod

@@ -2,4 +2,7 @@ module github.com/phoops/ngsiv2
 
 go 1.13
 
-require github.com/paulmach/go.geojson v1.4.0
+require (
+	github.com/mitchellh/mapstructure v1.4.2
+	github.com/paulmach/go.geojson v1.4.0
+)

go.sum

@@ -1,2 +1,4 @@
+github.com/mitchellh/mapstructure v1.4.2 h1:6h7AQ0yhTcIsmFmnAwQls75jp2Gzs4iB8W7pjMO+rqo=
+github.com/mitchellh/mapstructure v1.4.2/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
 github.com/paulmach/go.geojson v1.4.0 h1:5x5moCkCtDo5x8af62P9IOAYGQcYHtxz2QJ3x1DoCgY=
 github.com/paulmach/go.geojson v1.4.0/go.mod h1:YaKx1hKpWF+T2oj2lFJPsW/t1Q5e1jQI61eoQSTwpIs=

model/model.go

@@ -10,6 +10,7 @@ import (
 	"time"
 	"unicode"
 
+	"github.com/mitchellh/mapstructure"
 	geojson "github.com/paulmach/go.geojson"
 )
 
@@ -41,20 +42,22 @@ type Metadata struct {
 
 type AttributeType string
 
+// Constants representing NGSIv2 special data types
 const (
-	StringType     AttributeType = "String"
-	TextType       AttributeType = "Text"
-	NumberType     AttributeType = "Number"
-	FloatType      AttributeType = "Float"
-	IntegerType    AttributeType = "Integer"
-	BooleanType    AttributeType = "Boolean"
-	PercentageType AttributeType = "Percentage"
-	DateTimeType   AttributeType = "DateTime"
-	GeoPointType   AttributeType = "geo:point"
-	GeoLineType    AttributeType = "geo:line"
-	GeoPolygonType AttributeType = "geo:polygon"
-	GeoBoxType     AttributeType = "geo:box"
-	GeoJSONType    AttributeType = "geo:json"
+	StringType          AttributeType = "String"
+	TextType            AttributeType = "Text"
+	NumberType          AttributeType = "Number"
+	FloatType           AttributeType = "Float"
+	IntegerType         AttributeType = "Integer"
+	BooleanType         AttributeType = "Boolean"
+	PercentageType      AttributeType = "Percentage"
+	DateTimeType        AttributeType = "DateTime"
+	GeoPointType        AttributeType = "geo:point"
+	GeoLineType         AttributeType = "geo:line"
+	GeoPolygonType      AttributeType = "geo:polygon"
+	GeoBoxType          AttributeType = "geo:box"
+	GeoJSONType         AttributeType = "geo:json"
+	StructuredValueType AttributeType = "StructuredValue"
 )
 
 const (
@@ -683,6 +686,19 @@ func (e *Entity) SetAttributeAsGeoJSON(name string, value *geojson.Geometry) err
 	return nil
 }
 
+func (e *Entity) SetAttributeAsStructuredValue(name string, value interface{}) error {
+	if err := validateAttributeName(name); err != nil {
+		return err
+	}
+	e.Attributes[name] = &Attribute{
+		typeValue: typeValue{
+			Type:  StructuredValueType,
+			Value: value,
+		},
+	}
+	return nil
+}
+
 func (a *Attribute) GetAsString() (string, error) {
 	if a.Type != StringType && a.Type != TextType {
 		return "", fmt.Errorf("Attribute is nor String or Text, but %s", a.Type)
@@ -765,6 +781,16 @@ func (a *Attribute) GetAsGeoJSON() (*geojson.Geometry, error) {
 	return g, nil
 }
 
+// DecodeStructuredValue decodes the attribute into output if attribute type is StructuredValue.
+// output must be a pointer to a map or struct.
+func (a *Attribute) DecodeStructuredValue(output interface{}) error {
+	if a.Type != StructuredValueType {
+		return fmt.Errorf("Attribute is not %s, but '%s'", StructuredValueType, a.Type)
+	}
+
+	return mapstructure.Decode(a.Value, output)
+}
+
 func (e *Entity) GetAttributeAsString(attributeName string) (string, error) {
 	if a, err := e.GetAttribute(attributeName); err != nil {
 		return "", err
@@ -845,6 +871,16 @@ func (e *Entity) GetAttributeAsGeoJSON(attributeName string) (*geojson.Geometry,
 	return a.GetAsGeoJSON()
 }
 
+// DecodeStructuredValueAttribute decodes the attribute named attributeName into output if
+// attribute type is StructuredValue. output must be a pointer to a map or struct.
+func (e *Entity) DecodeStructuredValueAttribute(attributeName string, output interface{}) error {
+	a, err := e.GetAttribute(attributeName)
+	if err != nil {
+		return err
+	}
+	return a.DecodeStructuredValue(output)
+}
+
 func NewBatchUpdate(action ActionType) *BatchUpdate {
 	b := &BatchUpdate{ActionType: action}
 	return b

model/model_test.go

@@ -321,6 +321,75 @@ func TestEntityUnmarshal(t *testing.T) {
 	} else {
 		t.Fatal("Expected error on getting a nasty boolean, got nil")
 	}
+
+	structuredVal := `
+	{
+		"id": "Structured1",
+		"manufacturers": {
+			"metadata": {},
+			"type": "StructuredValue",
+			"value": [
+				"Audi",
+				"Alfa Romeo",
+				"BMW"
+			]
+		},
+		"seller": {
+			"metadata": {},
+			"type": "StructuredValue",
+			"value": {
+				"name": "Jane",
+				"age": 25
+			}
+		}
+	}
+	`
+
+	structuredEntity := &model.Entity{}
+	if err := json.Unmarshal([]byte(structuredVal), structuredEntity); err != nil {
+		t.Fatalf("Error unmarshaling entity: %v", err)
+	}
+
+	manufacturersAttr, err := structuredEntity.GetAttribute("manufacturers")
+	if err != nil {
+		t.Fatalf("Unexpected error: '%v'", err)
+	}
+	if manufacturersAttr.Type != model.StructuredValueType {
+		t.Fatalf("Expected '%s' for manufacturers attribute type, got '%s'", model.StructuredValueType, manufacturersAttr.Type)
+	}
+
+	type intarray []int
+	type stringarray []string
+	manufacturersInt := make(intarray, 0)
+	manufacturersString := make(stringarray, 0)
+	if err := manufacturersAttr.DecodeStructuredValue(&manufacturersInt); err == nil {
+		t.Fatal("Expected a failure on non integers 'manufacturers'")
+	}
+	err = manufacturersAttr.DecodeStructuredValue(&manufacturersString)
+	if err != nil {
+		t.Fatalf("Unexpected error: '%v'", err)
+	}
+	if len(manufacturersString) != 3 {
+		t.Fatalf("Expected '%d' manufacturers, got '%d'", 3, len(manufacturersString))
+	}
+	if manufacturersString[2] != "BMW" {
+		t.Fatalf("Expected 'BMW' as third manufacturer, got '%s'", manufacturersString[2])
+	}
+
+	type Person struct {
+		Name string
+		Age  int
+	}
+
+	person := new(Person)
+	err = structuredEntity.DecodeStructuredValueAttribute("seller", person)
+	if err != nil {
+		t.Fatalf("Unexpected error: '%v'", err)
+	}
+
+	if person.Name != "Jane" || person.Age != 25 {
+		t.Fatalf("Expected Jane, got '%v'", *person)
+	}
 }
 
 func TestEntityMarshal(t *testing.T) {
@@ -352,6 +421,16 @@ func TestEntityMarshal(t *testing.T) {
 	geoJsonPoint := geojson.NewPointGeometry([]float64{4.1, 2.3})
 	office.SetAttributeAsGeoJSON("position", geoJsonPoint)
 
+	type Dog struct {
+		Name string
+		Age  int
+	}
+
+	ambra := &Dog{"Ambra", 4}
+	if err := office.SetAttributeAsStructuredValue("mascot", ambra); err != nil {
+		t.Fatalf("Unexpected error: '%v'", err)
+	}
+
 	bytes, err := json.Marshal(office)
 	if err != nil {
 		t.Fatalf("Unexpected error: '%v'", err)
@@ -481,6 +560,21 @@ func TestEntityMarshal(t *testing.T) {
 			}
 		}
 	}
+
+	mascotAttr, err := unmarshaled.GetAttribute("mascot")
+	if err != nil {
+		t.Fatalf("Unexpected error: '%v'", err)
+	}
+	if mascotAttr.Type != model.StructuredValueType {
+		t.Fatalf("Expected %s type, got '%s'", model.StructuredValueType, mascotAttr.Type)
+	}
+	mascot := new(Dog)
+	if err := mascotAttr.DecodeStructuredValue(mascot); err != nil {
+		t.Fatalf("Unexpected error: '%v'", err)
+	}
+	if mascot.Name != "Ambra" || mascot.Age != 4 {
+		t.Fatalf("Expected Ambra as mascot, got '%v'", mascot)
+	}
 }
 
 func TestDirectEntityAttributeAccess(t *testing.T) {