Serve outbox for Actor (#289)

* add statusesvisible convenience function

* add minID + onlyPublic to account statuses get

* move swagger collection stuff to common

* start working on Outbox GETting

* move functions into federationProcessor

* outboxToASCollection

* add statusesvisible convenience function

* add minID + onlyPublic to account statuses get

* move swagger collection stuff to common

* start working on Outbox GETting

* move functions into federationProcessor

* outboxToASCollection

* bit more work on outbox paging

* wrapNoteInCreate function

* test + hook up the processor functions

* don't do prev + next links on empty reply

* test get outbox through api

* don't fail on no status entries

* add outbox implementation doc

* typo

internal/api/s2s/user/common.go

@@ -57,3 +57,41 @@ func negotiateFormat(c *gin.Context) (string, error) {
 	}
 	return format, nil
 }
+
+// SwaggerCollection represents an activitypub collection.
+// swagger:model swaggerCollection
+type SwaggerCollection struct {
+	// ActivityStreams context.
+	// example: https://www.w3.org/ns/activitystreams
+	Context string `json:"@context"`
+	// ActivityStreams ID.
+	// example: https://example.org/users/some_user/statuses/106717595988259568/replies
+	ID string `json:"id"`
+	// ActivityStreams type.
+	// example: Collection
+	Type string `json:"type"`
+	// ActivityStreams first property.
+	First SwaggerCollectionPage `json:"first"`
+	// ActivityStreams last property.
+	Last SwaggerCollectionPage `json:"last,omitempty"`
+}
+
+// SwaggerCollectionPage represents one page of a collection.
+// swagger:model swaggerCollectionPage
+type SwaggerCollectionPage struct {
+	// ActivityStreams ID.
+	// example: https://example.org/users/some_user/statuses/106717595988259568/replies?page=true
+	ID string `json:"id"`
+	// ActivityStreams type.
+	// example: CollectionPage
+	Type string `json:"type"`
+	// Link to the next page.
+	// example: https://example.org/users/some_user/statuses/106717595988259568/replies?only_other_accounts=true&page=true
+	Next string `json:"next"`
+	// Collection this page belongs to.
+	// example: https://example.org/users/some_user/statuses/106717595988259568/replies
+	PartOf string `json:"partOf"`
+	// Items on this page.
+	// example: ["https://example.org/users/some_other_user/statuses/086417595981111564", "https://another.example.com/users/another_user/statuses/01FCN8XDV3YG7B4R42QA6YQZ9R"]
+	Items []string `json:"items"`
+}