Skip request stage on mutual follow

If George follows you, and you want to follow George, you no longer have to get George's permission.

Closes #13

apps/api/src/routes/addUserFollow.test.ts

@@ -96,3 +96,46 @@ test("can follow existing link", async () => {
  expect(newFollow).toBeDefined();
  expect(newFollow.status).toBe(follow.status);
 });
+
+test("automatically approves follow when mutual", async () => {
+ const otherUser = await Fixtures.User();
+ await Fixtures.Follow({
+ fromUserId: otherUser.id,
+ toUserId: DefaultFixtures.user.id,
+ status: "following",
+ });
+
+ const response = await app.inject({
+ method: "POST",
+ url: `/users/${otherUser.id}/follow`,
+ headers: DefaultFixtures.authHeaders,
+ });
+
+ expect(response).toRespondWith(200);
+ const data = JSON.parse(response.payload);
+ expect(data.status).toBe("following");
+
+ const [follow] = await db
+ .select()
+ .from(follows)
+ .where(
+ and(
+ eq(follows.fromUserId, DefaultFixtures.user.id),
+ eq(follows.toUserId, otherUser.id),
+ ),
+ );
+ expect(follow).toBeDefined();
+ expect(follow.status).toBe("following");
+
+ const [notif] = await db
+ .select()
+ .from(notifications)
+ .where(
+ and(
+ eq(notifications.objectId, follow.id),
+ eq(notifications.objectType, objectTypeFromSchema(follows)),
+ ),
+ );
+
+ expect(notif).toBeUndefined();
+});

apps/api/src/routes/addUserFollow.ts

@@ -33,6 +33,21 @@ export default {
  return res.status(404).send({ error: "Not found" });
  }
 
+ // XXX: could make this a subquery to avoid a small race
+ const isFollowedBy =
+ (
+ await db
+ .select()
+ .from(follows)
+ .where(
+ and(
+ eq(follows.fromUserId, user.id),
+ eq(follows.toUserId, req.user.id),
+ eq(follows.status, "following"),
+ ),
+ )
+ ).length === 1;
+
  const follow = await db.transaction(async (tx) => {
  const follow =
  first<Follow>(
@@ -41,6 +56,7 @@ export default {
  .values({
  fromUserId: req.user.id,
  toUserId: user.id,
+ status: isFollowedBy ? "following" : "pending",
  })
  .onConflictDoNothing()
  .returning(),
@@ -49,7 +65,7 @@ export default {
  await tx
  .update(follows)
  .set({
- status: "pending",
+ status: isFollowedBy ? "following" : "pending",
  })
  .where(
  and(
@@ -72,13 +88,14 @@ export default {
  )
  )[0];
 
- createNotification(tx, {
- fromUserId: follow.fromUserId,
- objectType: objectTypeFromSchema(follows),
- objectId: follow.id,
- createdAt: follow.createdAt,
- userId: follow.toUserId,
- });
+ if (follow.status === "pending")
+ createNotification(tx, {
+ fromUserId: follow.fromUserId,
+ objectType: objectTypeFromSchema(follows),
+ objectId: follow.id,
+ createdAt: follow.createdAt,
+ userId: follow.toUserId,
+ });
 
  return follow;
  });