Merge pull request #17 from jkongie/jsonapi-relationship-unmarshal

Update Relationship data structures to follow the spec.

Author: Derek Dowling

object.go

@@ -10,11 +10,11 @@ import (
 
 // Object represents the default JSON spec for objects
 type Object struct {
-	Type          string             `json:"type" valid:"required"`
-	ID            string             `json:"id"`
-	Attributes    json.RawMessage    `json:"attributes,omitempty"`
-	Links         map[string]*Link   `json:"links,omitempty"`
-	Relationships map[string]*Object `json:"relationships,omitempty"`
+	Type          string                   `json:"type" valid:"required"`
+	ID            string                   `json:"id"`
+	Attributes    json.RawMessage          `json:"attributes,omitempty"`
+	Links         map[string]*Link         `json:"links,omitempty"`
+	Relationships map[string]*Relationship `json:"relationships,omitempty"`
 	// Status is the HTTP Status Code that should be associated with the object
 	// when it is sent.
 	Status int `json:"-"`
@@ -27,7 +27,7 @@ func NewObject(id string, resourceType string, attributes interface{}) (*Object,
 		ID:            id,
 		Type:          resourceType,
 		Links:         map[string]*Link{},
-		Relationships: map[string]*Object{},
+		Relationships: map[string]*Relationship{},
 	}
 
 	rawJSON, err := json.MarshalIndent(attributes, "", " ")

parser_test.go

@@ -26,7 +26,24 @@ func TestParsing(t *testing.T) {
 
 			Convey("should parse a valid object", func() {
 
-				objectJSON := `{"data": {"type": "user", "id": "sweetID123", "attributes": {"ID":"123"}}}`
+				objectJSON := `{
+					"data": {
+						"type": "user",
+						"id": "sweetID123",
+						"attributes": {"ID":"123"},
+						"relationships": {
+							"company": {
+								"data": { "type": "company", "id": "companyID123" }
+							},
+							"comments": {
+								"data": [
+									{ "type": "comments", "id": "commentID123" },
+									{ "type": "comments", "id": "commentID456" }
+								]
+							}
+						}
+					}
+				}`
 				req, reqErr := testRequest([]byte(objectJSON))
 				So(reqErr, ShouldBeNil)
 
@@ -37,6 +54,8 @@ func TestParsing(t *testing.T) {
 				So(object.Type, ShouldEqual, "user")
 				So(object.ID, ShouldEqual, "sweetID123")
 				So(object.Attributes, ShouldResemble, json.RawMessage(`{"ID":"123"}`))
+				So(object.Relationships["company"], ShouldResemble, &Relationship{Data: ResourceLinkage{&ResourceIdentifier{Type: "company", ID: "companyID123"}}})
+				So(object.Relationships["comments"], ShouldResemble, &Relationship{Data: ResourceLinkage{{Type: "comments", ID: "commentID123"}, {Type: "comments", ID: "commentID456"}}})
 			})
 
 			Convey("should reject an object with missing attributes", func() {

relationship.go

@@ -0,0 +1,53 @@
+package jsh
+
+import (
+	"fmt"
+
+	"encoding/json"
+)
+
+// Relationship represents a reference from the resource object in which it's
+// defined to other resource objects.
+type Relationship struct {
+	Links *Links                 `json:"links,omitempty"`
+	Data  ResourceLinkage        `json:"data,omitempty"`
+	Meta  map[string]interface{} `json:"meta,omitempty"`
+}
+
+// ResourceLinkage is a typedef around a slice of resource identifiers. This
+// allows us to implement a custom UnmarshalJSON.
+type ResourceLinkage []*ResourceIdentifier
+
+// ResourceIdentifier identifies an individual resource.
+type ResourceIdentifier struct {
+	Type string `json:"type" valid:"required"`
+	ID   string `json:"id" valid:"required"`
+}
+
+/*
+UnmarshalJSON allows us to manually decode a the resource linkage via the
+json.Unmarshaler interface.
+*/
+func (rl *ResourceLinkage) UnmarshalJSON(data []byte) error {
+	// Create a sub-type here so when we call Unmarshal below, we don't recursively
+	// call this function over and over
+	type UnmarshalLinkage ResourceLinkage
+
+	// if our "List" is a single object, modify the JSON to make it into a list
+	// by wrapping with "[ ]"
+	if data[0] == '{' {
+		data = []byte(fmt.Sprintf("[%s]", data))
+	}
+
+	newLinkage := UnmarshalLinkage{}
+
+	err := json.Unmarshal(data, &newLinkage)
+	if err != nil {
+		return err
+	}
+
+	convertedLinkage := ResourceLinkage(newLinkage)
+	*rl = convertedLinkage
+
+	return nil
+}

relationship_test.go

@@ -0,0 +1,35 @@
+package jsh
+
+import (
+	"testing"
+
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+func TestRelationship(t *testing.T) {
+	Convey("ResourceLinkage Tests", t, func() {
+		Convey("->UnmarshalJSON()", func() {
+
+			Convey("should handle a linkage object", func() {
+				jObj := `{"type": "testRelationship", "id": "ID456"}`
+
+				rl := ResourceLinkage{}
+				err := rl.UnmarshalJSON([]byte(jObj))
+				So(err, ShouldBeNil)
+				So(len(rl), ShouldEqual, 1)
+			})
+
+			Convey("should handle a linkage list", func() {
+				jList := `[
+					{"type": "testRelationship", "id": "ID456"},
+					{"type": "testRelationship", "id": "ID789"}
+				]`
+
+				rl := ResourceLinkage{}
+				err := rl.UnmarshalJSON([]byte(jList))
+				So(err, ShouldBeNil)
+				So(len(rl), ShouldEqual, 2)
+			})
+		})
+	})
+}