[feature] Add paging via `Link` header for notifications and account statuses (#629)

* test link headers

* page get account statuses properly

* page get notifications

* add util func for packaging timeline responses

* return timelined stuff from accountstatusesget

* rename timeline response

* use new convenience function

* go fmt

2 files changed, 26 insertions, 3 deletions

diff --git a/internal/api/model/notification.go b/internal/api/model/notification.go
index 8f929cab4..efcd2431b 100644
--- a/internal/api/model/notification.go
+++ b/internal/api/model/notification.go
@@ -43,3 +43,24 @@ type Notification struct {
 	// Status that was the object of the notification, e.g. in mentions, reblogs, favourites, or polls.
 	Status *Status `json:"status,omitempty"`
 }
+
+/*
+	The below functions are added onto the apimodel notification so that it satisfies
+	the Timelineable interface in internal/timeline.
+*/
+
+func (n *Notification) GetID() string {
+	return n.ID
+}
+
+func (n *Notification) GetAccountID() string {
+	return ""
+}
+
+func (n *Notification) GetBoostOfID() string {
+	return ""
+}
+
+func (n *Notification) GetBoostOfAccountID() string {
+	return ""
+}
diff --git a/internal/api/model/timeline.go b/internal/api/model/timeline.go
index 66a5263b8..71d839ed2 100644
--- a/internal/api/model/timeline.go
+++ b/internal/api/model/timeline.go
@@ -18,9 +18,11 @@
 
 package model
 
-// StatusTimelineResponse wraps a slice of statuses, ready to be serialized, along with the Link
+import "github.com/superseriousbusiness/gotosocial/internal/timeline"
+
+// TimelineResponse wraps a slice of timelineables, ready to be serialized, along with the Link
 // header for the previous and next queries, to be returned to the client.
-type StatusTimelineResponse struct {
-	Statuses   []*Status
+type TimelineResponse struct {
+	Items      []timeline.Timelineable
 	LinkHeader string
 }