Merge pull request #10 from hashicorp/add-links-unmarshaling

Unmarshal Links type to 'links' annotated struct fields

README.md

@@ -179,6 +179,18 @@ used as the key in the `relationships` hash for the record. The optional
 third argument is `omitempty` - if present will prevent non existent to-one and
 to-many from being serialized.
 
+#### `links`
+
+*Note: This annotation is an added feature independent of the canonical google/jsonapi package*
+
+```
+`jsonapi:"links,omitempty"`
+```
+
+A field annotated with `links` will have the links members of the request unmarshaled to it. Note
+that this field should _always_ be annotated with `omitempty`, as marshaling of links members is
+instead handled by the `Linkable` interface (see `Links` below).
+
 ## Methods Reference
 
 **All `Marshal` and `Unmarshal` methods expect pointers to struct

constants.go

@@ -7,6 +7,7 @@ const (
 	annotationClientID  = "client-id"
 	annotationAttribute = "attr"
 	annotationRelation  = "relation"
+	annotationLinks     = "links"
 	annotationOmitEmpty = "omitempty"
 	annotationISO8601   = "iso8601"
 	annotationRFC3339   = "rfc3339"
@@ -53,4 +54,8 @@ const (
 	// QueryParamPageCursor is a JSON API query parameter used with a cursor-based
 	// strategy
 	QueryParamPageCursor = "page[cursor]"
+
+	// KeySelfLink is the key within a top-level links object that denotes the link that
+	// generated the current response document.
+	KeySelfLink = "self"
 )

models_test.go

@@ -51,13 +51,17 @@ type Post struct {
 	Body          string     `jsonapi:"attr,body"`
 	Comments      []*Comment `jsonapi:"relation,comments"`
 	LatestComment *Comment   `jsonapi:"relation,latest_comment"`
+
+	Links Links `jsonapi:"links,omitempty"`
 }
 
 type Comment struct {
 	ID       int    `jsonapi:"primary,comments"`
 	ClientID string `jsonapi:"client-id"`
 	PostID   int    `jsonapi:"attr,post_id"`
 	Body     string `jsonapi:"attr,body"`
+
+	Links Links `jsonapi:"links,omitempty"`
 }
 
 type Book struct {
@@ -80,6 +84,8 @@ type Blog struct {
 	CurrentPostID int       `jsonapi:"attr,current_post_id"`
 	CreatedAt     time.Time `jsonapi:"attr,created_at"`
 	ViewCount     int       `jsonapi:"attr,view_count"`
+
+	Links Links `jsonapi:"links,omitempty"`
 }
 
 func (b *Blog) JSONAPILinks() *Links {

request.go

@@ -327,6 +327,46 @@ func unmarshalNode(data *Node, model reflect.Value, included *map[string]*Node)
 
 			}
 
+		} else if annotation == annotationLinks {
+			if data.Links == nil {
+				continue
+			}
+
+			links := make(Links, len(*data.Links))
+
+			for k, v := range *data.Links {
+				link := v // default case (including string urls)
+
+				// Unmarshal link objects to Link
+				if t, ok := v.(map[string]interface{}); ok {
+					unmarshaledHref := ""
+					href, ok := t["href"].(string)
+					if ok {
+						unmarshaledHref = href
+					}
+
+					unmarshaledMeta := make(Meta)
+					if meta, ok := t["meta"].(map[string]interface{}); ok {
+						for metaK, metaV := range meta {
+							unmarshaledMeta[metaK] = metaV
+						}
+					}
+
+					link = Link{
+						Href: unmarshaledHref,
+						Meta: unmarshaledMeta,
+					}
+				}
+
+				links[k] = link
+			}
+
+			if err != nil {
+				er = err
+				break
+			}
+
+			assign(fieldValue, reflect.ValueOf(links))
 		} else {
 			er = fmt.Errorf(unsupportedStructTagMsg, annotation)
 		}

request_test.go

@@ -745,6 +745,35 @@ func TestUnmarshalNestedRelationshipsEmbedded_withClientIDs(t *testing.T) {
 	}
 }
 
+func TestUnmarshalLinks(t *testing.T) {
+	model := new(Blog)
+
+	if err := UnmarshalPayload(samplePayload(), model); err != nil {
+		t.Fatal(err)
+	}
+
+	if model.Links == nil {
+		t.Fatalf("Expected Links field on model to be set")
+	}
+
+	if e, a := "http://somesite.com/blogs/1", model.Links[KeySelfLink]; e != a {
+		t.Fatalf("Was expecting links.%s to have a value of %s, got %s", KeySelfLink, e, a)
+	}
+
+	if e, a := "http://somesite.com/posts/1", model.Posts[0].Links[KeySelfLink]; e != a {
+		t.Fatalf("Was expecting posts.0.links.%s to have a value of %s, got %s", KeySelfLink, e, a)
+	}
+
+	expectedLinkObject := Link{Href: "http://somesite.com/posts/2", Meta: Meta{"foo": "bar"}}
+	if e, a := expectedLinkObject, model.CurrentPost.Links[KeySelfLink]; !reflect.DeepEqual(e, a) {
+		t.Fatalf("Was expecting posts.0.links.%s to have a value of %s, got %s", KeySelfLink, e, a)
+	}
+
+	if e, a := "http://somesite.com/comments/1", model.CurrentPost.Comments[0].Links[KeySelfLink]; e != a {
+		t.Fatalf("Was expecting posts.0.links.%s to have a value of %s, got %s", KeySelfLink, e, a)
+	}
+}
+
 func unmarshalSamplePayload() (*Blog, error) {
 	in := samplePayload()
 	out := new(Blog)
@@ -801,6 +830,32 @@ func TestUnmarshalManyPayload(t *testing.T) {
 	}
 }
 
+func TestOnePayload_withLinks(t *testing.T) {
+	rawJSON := []byte("{\"data\": { \"type\": \"posts\", \"id\": \"1\", \"attributes\": { \"body\": \"First\", \"title\": \"Post\" } }, \"links\": { \"self\": \"http://somesite.com/posts/1\" } }")
+
+	in := bytes.NewReader(rawJSON)
+
+	payload := new(OnePayload)
+	if err := json.NewDecoder(in).Decode(payload); err != nil {
+		t.Fatal(err)
+	}
+
+	if payload.Links == nil {
+		t.Fatal("Was expecting a non nil ptr Link field")
+	}
+
+	links := *payload.Links
+
+	self, ok := links[KeySelfLink]
+	if !ok {
+		t.Fatal("Was expecting a non nil 'self' link field")
+	}
+	if e, a := "http://somesite.com/posts/1", self; e != a {
+		t.Fatalf("Was expecting links.%s to have a value of %s, got %s", KeySelfLink, e, a)
+	}
+
+}
+
 func TestManyPayload_withLinks(t *testing.T) {
 	firstPageURL := "http://somesite.com/movies?page[limit]=50&page[offset]=50"
 	prevPageURL := "http://somesite.com/movies?page[limit]=50&page[offset]=0"
@@ -1016,6 +1071,9 @@ func samplePayload() io.Reader {
 								"body":  "Bar",
 							},
 							ClientID: "1",
+							Links: &Links{
+								"self": "http://somesite.com/posts/1",
+							},
 						},
 						{
 							Type: "posts",
@@ -1024,6 +1082,9 @@ func samplePayload() io.Reader {
 								"body":  "Y",
 							},
 							ClientID: "2",
+							Links: &Links{
+								"self": "http://somesite.com/posts/2",
+							},
 						},
 					},
 				},
@@ -1044,20 +1105,37 @@ func samplePayload() io.Reader {
 											"body": "Great post!",
 										},
 										ClientID: "4",
+										Links: &Links{
+											"self": "http://somesite.com/comments/1",
+										},
 									},
 									{
 										Type: "comments",
 										Attributes: map[string]interface{}{
 											"body": "Needs some work!",
 										},
 										ClientID: "5",
+										Links: &Links{
+											"self": "http://somesite.com/comments/2",
+										},
 									},
 								},
 							},
 						},
+						Links: &Links{
+							"self": &Link{
+								Href: "http://somesite.com/posts/2",
+								Meta: Meta{
+									"foo": "bar",
+								},
+							},
+						},
 					},
 				},
 			},
+			Links: &Links{
+				"self": "http://somesite.com/blogs/1",
+			},
 		},
 	}
 

response.go

@@ -447,7 +447,9 @@ func visitModelNode(model interface{}, included *map[string]*Node,
 					}
 				}
 			}
-
+		} else if annotation == annotationLinks {
+			// Nothing. Ignore this field, as Links fields are only for unmarshaling requests.
+			// The Linkable interface methods are used for marshaling data in a response.
 		} else {
 			er = ErrBadJSONAPIStructTag
 			break