Follows and relationships (#27)

* Follows -- create and undo, both remote and local
* Statuses -- federate new posts, including media, attachments, CWs and image descriptions.

internal/util/uri.go

@@ -22,6 +22,8 @@ import (
 	"fmt"
 	"net/url"
 	"strings"
+
+	"github.com/google/uuid"
 )
 
 const (
@@ -47,6 +49,8 @@ const (
 	FeaturedPath = "featured"
 	// PublicKeyPath is for serving an account's public key
 	PublicKeyPath = "main-key"
+	// FollowPath used to generate the URI for an individual follow or follow request
+	FollowPath = "follow"
 )
 
 // APContextKey is a type used specifically for settings values on contexts within go-fed AP request chains
@@ -103,6 +107,12 @@ type UserURIs struct {
 	PublicKeyURI string
 }
 
+// GenerateURIForFollow returns the AP URI for a new follow -- something like:
+// https://example.org/users/whatever_user/follow/41c7f33f-1060-48d9-84df-38dcb13cf0d8
+func GenerateURIForFollow(username string, protocol string, host string) string {
+	return fmt.Sprintf("%s://%s/%s/%s/%s", protocol, host, UsersPath, FollowPath, uuid.NewString())
+}
+
 // GenerateURIsForAccount throws together a bunch of URIs for the given username, with the given protocol and host.
 func GenerateURIsForAccount(username string, protocol string, host string) *UserURIs {
 	// The below URLs are used for serving web requests