akkoma/test/web/activity_pub/activity_pub_test.exs

# Pleroma: A lightweight social networking server
# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only

defmodule Pleroma.Web.ActivityPub.ActivityPubTest do
  use Pleroma.DataCase
  alias Pleroma.Web.ActivityPub.ActivityPub
  alias Pleroma.Web.ActivityPub.Utils
  alias Pleroma.Web.CommonAPI
  alias Pleroma.Activity
  alias Pleroma.Object
  alias Pleroma.User
  alias Pleroma.Instances
  alias Pleroma.Builders.ActivityBuilder

  import Pleroma.Factory
  import Tesla.Mock
  import Mock

  setup do
    mock(fn env -> apply(HttpRequestMock, :request, [env]) end)
    :ok
  end

  describe "fetching restricted by visibility" do
    test "it restricts by the appropriate visibility" do
      user = insert(:user)

      {:ok, public_activity} = CommonAPI.post(user, %{"status" => ".", "visibility" => "public"})

      {:ok, direct_activity} = CommonAPI.post(user, %{"status" => ".", "visibility" => "direct"})

      {:ok, unlisted_activity} =
        CommonAPI.post(user, %{"status" => ".", "visibility" => "unlisted"})

      {:ok, private_activity} =
        CommonAPI.post(user, %{"status" => ".", "visibility" => "private"})

      activities =
        ActivityPub.fetch_activities([], %{:visibility => "direct", "actor_id" => user.ap_id})

      assert activities == [direct_activity]

      activities =
        ActivityPub.fetch_activities([], %{:visibility => "unlisted", "actor_id" => user.ap_id})

      assert activities == [unlisted_activity]

      activities =
        ActivityPub.fetch_activities([], %{:visibility => "private", "actor_id" => user.ap_id})

      assert activities == [private_activity]

      activities =
        ActivityPub.fetch_activities([], %{:visibility => "public", "actor_id" => user.ap_id})

      assert activities == [public_activity]
    end
  end

  describe "building a user from his ap id" do
    test "it returns a user" do
      user_id = "http://mastodon.example.org/users/admin"
      {:ok, user} = ActivityPub.make_user_from_ap_id(user_id)
      assert user.ap_id == user_id
      assert user.nickname == "admin@mastodon.example.org"
      assert user.info.source_data
      assert user.info.ap_enabled
      assert user.follower_address == "http://mastodon.example.org/users/admin/followers"
    end

    test "it fetches the appropriate tag-restricted posts" do
      user = insert(:user)

      {:ok, status_one} = CommonAPI.post(user, %{"status" => ". #test"})
      {:ok, status_two} = CommonAPI.post(user, %{"status" => ". #essais"})
      {:ok, status_three} = CommonAPI.post(user, %{"status" => ". #test #reject"})

      fetch_one = ActivityPub.fetch_activities([], %{"tag" => "test"})
      fetch_two = ActivityPub.fetch_activities([], %{"tag" => ["test", "essais"]})

      fetch_three =
        ActivityPub.fetch_activities([], %{
          "tag" => ["test", "essais"],
          "tag_reject" => ["reject"]
        })

      fetch_four =
        ActivityPub.fetch_activities([], %{
          "tag" => ["test"],
          "tag_all" => ["test", "reject"]
        })

      assert fetch_one == [status_one, status_three]
      assert fetch_two == [status_one, status_two, status_three]
      assert fetch_three == [status_one, status_two]
      assert fetch_four == [status_three]
    end
  end

  describe "insertion" do
    test "drops activities beyond a certain limit" do
      limit = Pleroma.Config.get([:instance, :remote_limit])

      random_text =
        :crypto.strong_rand_bytes(limit + 1)
        |> Base.encode64()
        |> binary_part(0, limit + 1)

      data = %{
        "ok" => true,
        "object" => %{
          "content" => random_text
        }
      }

      assert {:error, {:remote_limit_error, _}} = ActivityPub.insert(data)
    end

    test "doesn't drop activities with content being null" do
      data = %{
        "ok" => true,
        "object" => %{
          "content" => nil
        }
      }

      assert {:ok, _} = ActivityPub.insert(data)
    end

    test "returns the activity if one with the same id is already in" do
      activity = insert(:note_activity)
      {:ok, new_activity} = ActivityPub.insert(activity.data)

      assert activity == new_activity
    end

    test "inserts a given map into the activity database, giving it an id if it has none." do
      data = %{
        "ok" => true
      }

      {:ok, %Activity{} = activity} = ActivityPub.insert(data)
      assert activity.data["ok"] == data["ok"]
      assert is_binary(activity.data["id"])

      given_id = "bla"

      data = %{
        "ok" => true,
        "id" => given_id,
        "context" => "blabla"
      }

      {:ok, %Activity{} = activity} = ActivityPub.insert(data)
      assert activity.data["ok"] == data["ok"]
      assert activity.data["id"] == given_id
      assert activity.data["context"] == "blabla"
      assert activity.data["context_id"]
    end

    test "adds a context when none is there" do
      data = %{
        "id" => "some_id",
        "object" => %{
          "id" => "object_id"
        }
      }

      {:ok, %Activity{} = activity} = ActivityPub.insert(data)

      assert is_binary(activity.data["context"])
      assert is_binary(activity.data["object"]["context"])
      assert activity.data["context_id"]
      assert activity.data["object"]["context_id"]
    end

    test "adds an id to a given object if it lacks one and is a note and inserts it to the object database" do
      data = %{
        "object" => %{
          "type" => "Note",
          "ok" => true
        }
      }

      {:ok, %Activity{} = activity} = ActivityPub.insert(data)
      assert is_binary(activity.data["object"]["id"])
      assert %Object{} = Object.get_by_ap_id(activity.data["object"]["id"])
    end
  end

  describe "create activities" do
    test "removes doubled 'to' recipients" do
      user = insert(:user)

      {:ok, activity} =
        ActivityPub.create(%{
          to: ["user1", "user1", "user2"],
          actor: user,
          context: "",
          object: %{}
        })

      assert activity.data["to"] == ["user1", "user2"]
      assert activity.actor == user.ap_id
      assert activity.recipients == ["user1", "user2", user.ap_id]
    end
  end

  describe "fetch activities for recipients" do
    test "retrieve the activities for certain recipients" do
      {:ok, activity_one} = ActivityBuilder.insert(%{"to" => ["someone"]})
      {:ok, activity_two} = ActivityBuilder.insert(%{"to" => ["someone_else"]})
      {:ok, _activity_three} = ActivityBuilder.insert(%{"to" => ["noone"]})

      activities = ActivityPub.fetch_activities(["someone", "someone_else"])
      assert length(activities) == 2
      assert activities == [activity_one, activity_two]
    end
  end

  describe "fetch activities in context" do
    test "retrieves activities that have a given context" do
      {:ok, activity} = ActivityBuilder.insert(%{"type" => "Create", "context" => "2hu"})
      {:ok, activity_two} = ActivityBuilder.insert(%{"type" => "Create", "context" => "2hu"})
      {:ok, _activity_three} = ActivityBuilder.insert(%{"type" => "Create", "context" => "3hu"})
      {:ok, _activity_four} = ActivityBuilder.insert(%{"type" => "Announce", "context" => "2hu"})
      activity_five = insert(:note_activity)
      user = insert(:user)

      {:ok, user} = User.block(user, %{ap_id: activity_five.data["actor"]})

      activities = ActivityPub.fetch_activities_for_context("2hu", %{"blocking_user" => user})
      assert activities == [activity_two, activity]
    end
  end

  test "doesn't return blocked activities" do
    activity_one = insert(:note_activity)
    activity_two = insert(:note_activity)
    activity_three = insert(:note_activity)
    user = insert(:user)
    booster = insert(:user)
    {:ok, user} = User.block(user, %{ap_id: activity_one.data["actor"]})

    activities = ActivityPub.fetch_activities([], %{"blocking_user" => user})

    assert Enum.member?(activities, activity_two)
    assert Enum.member?(activities, activity_three)
    refute Enum.member?(activities, activity_one)

    {:ok, user} = User.unblock(user, %{ap_id: activity_one.data["actor"]})

    activities = ActivityPub.fetch_activities([], %{"blocking_user" => user})

    assert Enum.member?(activities, activity_two)
    assert Enum.member?(activities, activity_three)
    assert Enum.member?(activities, activity_one)

    {:ok, user} = User.block(user, %{ap_id: activity_three.data["actor"]})
    {:ok, _announce, %{data: %{"id" => id}}} = CommonAPI.repeat(activity_three.id, booster)
    %Activity{} = boost_activity = Activity.get_create_by_object_ap_id(id)
    activity_three = Repo.get(Activity, activity_three.id)

    activities = ActivityPub.fetch_activities([], %{"blocking_user" => user})

    assert Enum.member?(activities, activity_two)
    refute Enum.member?(activities, activity_three)
    refute Enum.member?(activities, boost_activity)
    assert Enum.member?(activities, activity_one)

    activities = ActivityPub.fetch_activities([], %{"blocking_user" => nil})

    assert Enum.member?(activities, activity_two)
    assert Enum.member?(activities, activity_three)
    assert Enum.member?(activities, boost_activity)
    assert Enum.member?(activities, activity_one)
  end

  test "doesn't return muted activities" do
    activity_one = insert(:note_activity)
    activity_two = insert(:note_activity)
    activity_three = insert(:note_activity)
    user = insert(:user)
    booster = insert(:user)
    {:ok, user} = User.mute(user, %User{ap_id: activity_one.data["actor"]})

    activities = ActivityPub.fetch_activities([], %{"muting_user" => user})

    assert Enum.member?(activities, activity_two)
    assert Enum.member?(activities, activity_three)
    refute Enum.member?(activities, activity_one)

    # Calling with 'with_muted' will deliver muted activities, too.
    activities = ActivityPub.fetch_activities([], %{"muting_user" => user, "with_muted" => true})

    assert Enum.member?(activities, activity_two)
    assert Enum.member?(activities, activity_three)
    assert Enum.member?(activities, activity_one)

    {:ok, user} = User.unmute(user, %User{ap_id: activity_one.data["actor"]})

    activities = ActivityPub.fetch_activities([], %{"muting_user" => user})

    assert Enum.member?(activities, activity_two)
    assert Enum.member?(activities, activity_three)
    assert Enum.member?(activities, activity_one)

    {:ok, user} = User.mute(user, %User{ap_id: activity_three.data["actor"]})
    {:ok, _announce, %{data: %{"id" => id}}} = CommonAPI.repeat(activity_three.id, booster)
    %Activity{} = boost_activity = Activity.get_create_by_object_ap_id(id)
    activity_three = Repo.get(Activity, activity_three.id)

    activities = ActivityPub.fetch_activities([], %{"muting_user" => user})

    assert Enum.member?(activities, activity_two)
    refute Enum.member?(activities, activity_three)
    refute Enum.member?(activities, boost_activity)
    assert Enum.member?(activities, activity_one)

    activities = ActivityPub.fetch_activities([], %{"muting_user" => nil})

    assert Enum.member?(activities, activity_two)
    assert Enum.member?(activities, activity_three)
    assert Enum.member?(activities, boost_activity)
    assert Enum.member?(activities, activity_one)
  end

  test "excludes reblogs on request" do
    user = insert(:user)
    {:ok, expected_activity} = ActivityBuilder.insert(%{"type" => "Create"}, %{:user => user})
    {:ok, _} = ActivityBuilder.insert(%{"type" => "Announce"}, %{:user => user})

    [activity] = ActivityPub.fetch_user_activities(user, nil, %{"exclude_reblogs" => "true"})

    assert activity == expected_activity
  end

  describe "public fetch activities" do
    test "doesn't retrieve unlisted activities" do
      user = insert(:user)

      {:ok, _unlisted_activity} =
        CommonAPI.post(user, %{"status" => "yeah", "visibility" => "unlisted"})

      {:ok, listed_activity} = CommonAPI.post(user, %{"status" => "yeah"})

      [activity] = ActivityPub.fetch_public_activities()

      assert activity == listed_activity
    end

    test "retrieves public activities" do
      _activities = ActivityPub.fetch_public_activities()

      %{public: public} = ActivityBuilder.public_and_non_public()

      activities = ActivityPub.fetch_public_activities()
      assert length(activities) == 1
      assert Enum.at(activities, 0) == public
    end

    test "retrieves a maximum of 20 activities" do
      activities = ActivityBuilder.insert_list(30)
      last_expected = List.last(activities)

      activities = ActivityPub.fetch_public_activities()
      last = List.last(activities)

      assert length(activities) == 20
      assert last == last_expected
    end

    test "retrieves ids starting from a since_id" do
      activities = ActivityBuilder.insert_list(30)
      later_activities = ActivityBuilder.insert_list(10)
      since_id = List.last(activities).id
      last_expected = List.last(later_activities)

      activities = ActivityPub.fetch_public_activities(%{"since_id" => since_id})
      last = List.last(activities)

      assert length(activities) == 10
      assert last == last_expected
    end

    test "retrieves ids up to max_id" do
      _first_activities = ActivityBuilder.insert_list(10)
      activities = ActivityBuilder.insert_list(20)
      later_activities = ActivityBuilder.insert_list(10)
      max_id = List.first(later_activities).id
      last_expected = List.last(activities)

      activities = ActivityPub.fetch_public_activities(%{"max_id" => max_id})
      last = List.last(activities)

      assert length(activities) == 20
      assert last == last_expected
    end
  end

  describe "like an object" do
    test "adds a like activity to the db" do
      note_activity = insert(:note_activity)
      object = Object.get_by_ap_id(note_activity.data["object"]["id"])
      user = insert(:user)
      user_two = insert(:user)

      {:ok, like_activity, object} = ActivityPub.like(user, object)

      assert like_activity.data["actor"] == user.ap_id
      assert like_activity.data["type"] == "Like"
      assert like_activity.data["object"] == object.data["id"]
      assert like_activity.data["to"] == [User.ap_followers(user), note_activity.data["actor"]]
      assert like_activity.data["context"] == object.data["context"]
      assert object.data["like_count"] == 1
      assert object.data["likes"] == [user.ap_id]

      # Just return the original activity if the user already liked it.
      {:ok, same_like_activity, object} = ActivityPub.like(user, object)

      assert like_activity == same_like_activity
      assert object.data["likes"] == [user.ap_id]

      [note_activity] = Activity.get_all_create_by_object_ap_id(object.data["id"])
      assert note_activity.data["object"]["like_count"] == 1

      {:ok, _like_activity, object} = ActivityPub.like(user_two, object)
      assert object.data["like_count"] == 2
    end
  end

  describe "unliking" do
    test "unliking a previously liked object" do
      note_activity = insert(:note_activity)
      object = Object.get_by_ap_id(note_activity.data["object"]["id"])
      user = insert(:user)

      # Unliking something that hasn't been liked does nothing
      {:ok, object} = ActivityPub.unlike(user, object)
      assert object.data["like_count"] == 0

      {:ok, like_activity, object} = ActivityPub.like(user, object)
      assert object.data["like_count"] == 1

      {:ok, _, _, object} = ActivityPub.unlike(user, object)
      assert object.data["like_count"] == 0

      assert Repo.get(Activity, like_activity.id) == nil
    end
  end

  describe "announcing an object" do
    test "adds an announce activity to the db" do
      note_activity = insert(:note_activity)
      object = Object.get_by_ap_id(note_activity.data["object"]["id"])
      user = insert(:user)

      {:ok, announce_activity, object} = ActivityPub.announce(user, object)
      assert object.data["announcement_count"] == 1
      assert object.data["announcements"] == [user.ap_id]

      assert announce_activity.data["to"] == [
               User.ap_followers(user),
               note_activity.data["actor"]
             ]

      assert announce_activity.data["object"] == object.data["id"]
      assert announce_activity.data["actor"] == user.ap_id
      assert announce_activity.data["context"] == object.data["context"]
    end
  end

  describe "unannouncing an object" do
    test "unannouncing a previously announced object" do
      note_activity = insert(:note_activity)
      object = Object.get_by_ap_id(note_activity.data["object"]["id"])
      user = insert(:user)

      # Unannouncing an object that is not announced does nothing
      # {:ok, object} = ActivityPub.unannounce(user, object)
      # assert object.data["announcement_count"] == 0

      {:ok, announce_activity, object} = ActivityPub.announce(user, object)
      assert object.data["announcement_count"] == 1

      {:ok, unannounce_activity, object} = ActivityPub.unannounce(user, object)
      assert object.data["announcement_count"] == 0

      assert unannounce_activity.data["to"] == [
               User.ap_followers(user),
               announce_activity.data["actor"]
             ]

      assert unannounce_activity.data["type"] == "Undo"
      assert unannounce_activity.data["object"] == announce_activity.data
      assert unannounce_activity.data["actor"] == user.ap_id
      assert unannounce_activity.data["context"] == announce_activity.data["context"]

      assert Repo.get(Activity, announce_activity.id) == nil
    end
  end

  describe "uploading files" do
    test "copies the file to the configured folder" do
      file = %Plug.Upload{
        content_type: "image/jpg",
        path: Path.absname("test/fixtures/image.jpg"),
        filename: "an_image.jpg"
      }

      {:ok, %Object{} = object} = ActivityPub.upload(file)
      assert object.data["name"] == "an_image.jpg"
    end

    test "works with base64 encoded images" do
      file = %{
        "img" => data_uri()
      }

      {:ok, %Object{}} = ActivityPub.upload(file)
    end
  end

  describe "fetch the latest Follow" do
    test "fetches the latest Follow activity" do
      %Activity{data: %{"type" => "Follow"}} = activity = insert(:follow_activity)
      follower = Repo.get_by(User, ap_id: activity.data["actor"])
      followed = Repo.get_by(User, ap_id: activity.data["object"])

      assert activity == Utils.fetch_latest_follow(follower, followed)
    end
  end

  describe "fetching an object" do
    test "it fetches an object" do
      {:ok, object} =
        ActivityPub.fetch_object_from_id("http://mastodon.example.org/@admin/99541947525187367")

      assert activity = Activity.get_create_by_object_ap_id(object.data["id"])
      assert activity.data["id"]

      {:ok, object_again} =
        ActivityPub.fetch_object_from_id("http://mastodon.example.org/@admin/99541947525187367")

      assert [attachment] = object.data["attachment"]
      assert is_list(attachment["url"])

      assert object == object_again
    end

    test "it works with objects only available via Ostatus" do
      {:ok, object} = ActivityPub.fetch_object_from_id("https://shitposter.club/notice/2827873")
      assert activity = Activity.get_create_by_object_ap_id(object.data["id"])
      assert activity.data["id"]

      {:ok, object_again} =
        ActivityPub.fetch_object_from_id("https://shitposter.club/notice/2827873")

      assert object == object_again
    end

    test "it correctly stitches up conversations between ostatus and ap" do
      last = "https://mstdn.io/users/mayuutann/statuses/99568293732299394"
      {:ok, object} = ActivityPub.fetch_object_from_id(last)

      object = Object.get_by_ap_id(object.data["inReplyTo"])
      assert object
    end
  end

  describe "following / unfollowing" do
    test "creates a follow activity" do
      follower = insert(:user)
      followed = insert(:user)

      {:ok, activity} = ActivityPub.follow(follower, followed)
      assert activity.data["type"] == "Follow"
      assert activity.data["actor"] == follower.ap_id
      assert activity.data["object"] == followed.ap_id
    end

    test "creates an undo activity for the last follow" do
      follower = insert(:user)
      followed = insert(:user)

      {:ok, follow_activity} = ActivityPub.follow(follower, followed)
      {:ok, activity} = ActivityPub.unfollow(follower, followed)

      assert activity.data["type"] == "Undo"
      assert activity.data["actor"] == follower.ap_id

      assert is_map(activity.data["object"])
      assert activity.data["object"]["type"] == "Follow"
      assert activity.data["object"]["object"] == followed.ap_id
      assert activity.data["object"]["id"] == follow_activity.data["id"]
    end
  end

  describe "blocking / unblocking" do
    test "creates a block activity" do
      blocker = insert(:user)
      blocked = insert(:user)

      {:ok, activity} = ActivityPub.block(blocker, blocked)

      assert activity.data["type"] == "Block"
      assert activity.data["actor"] == blocker.ap_id
      assert activity.data["object"] == blocked.ap_id
    end

    test "creates an undo activity for the last block" do
      blocker = insert(:user)
      blocked = insert(:user)

      {:ok, block_activity} = ActivityPub.block(blocker, blocked)
      {:ok, activity} = ActivityPub.unblock(blocker, blocked)

      assert activity.data["type"] == "Undo"
      assert activity.data["actor"] == blocker.ap_id

      assert is_map(activity.data["object"])
      assert activity.data["object"]["type"] == "Block"
      assert activity.data["object"]["object"] == blocked.ap_id
      assert activity.data["object"]["id"] == block_activity.data["id"]
    end
  end

  describe "deletion" do
    test "it creates a delete activity and deletes the original object" do
      note = insert(:note_activity)
      object = Object.get_by_ap_id(note.data["object"]["id"])
      {:ok, delete} = ActivityPub.delete(object)

      assert delete.data["type"] == "Delete"
      assert delete.data["actor"] == note.data["actor"]
      assert delete.data["object"] == note.data["object"]["id"]

      assert Repo.get(Activity, delete.id) != nil

      assert Repo.get(Object, object.id).data["type"] == "Tombstone"
    end
  end

  describe "timeline post-processing" do
    test "it filters broken threads" do
      user1 = insert(:user)
      user2 = insert(:user)
      user3 = insert(:user)

      {:ok, user1} = User.follow(user1, user3)
      assert User.following?(user1, user3)

      {:ok, user2} = User.follow(user2, user3)
      assert User.following?(user2, user3)

      {:ok, user3} = User.follow(user3, user2)
      assert User.following?(user3, user2)

      {:ok, public_activity} = CommonAPI.post(user3, %{"status" => "hi 1"})

      {:ok, private_activity_1} =
        CommonAPI.post(user3, %{"status" => "hi 2", "visibility" => "private"})

      {:ok, private_activity_2} =
        CommonAPI.post(user2, %{
          "status" => "hi 3",
          "visibility" => "private",
          "in_reply_to_status_id" => private_activity_1.id
        })

      {:ok, private_activity_3} =
        CommonAPI.post(user3, %{
          "status" => "hi 4",
          "visibility" => "private",
          "in_reply_to_status_id" => private_activity_2.id
        })

      activities = ActivityPub.fetch_activities([user1.ap_id | user1.following])

      assert [public_activity, private_activity_1, private_activity_3] == activities
      assert length(activities) == 3

      activities = ActivityPub.contain_timeline(activities, user1)

      assert [public_activity, private_activity_1] == activities
      assert length(activities) == 2
    end
  end

  test "it can fetch plume articles" do
    {:ok, object} =
      ActivityPub.fetch_object_from_id(
        "https://baptiste.gelez.xyz/~/PlumeDevelopment/this-month-in-plume-june-2018/"
      )

    assert object
  end

  describe "update" do
    test "it creates an update activity with the new user data" do
      user = insert(:user)
      {:ok, user} = Pleroma.Web.WebFinger.ensure_keys_present(user)
      user_data = Pleroma.Web.ActivityPub.UserView.render("user.json", %{user: user})

      {:ok, update} =
        ActivityPub.update(%{
          actor: user_data["id"],
          to: [user.follower_address],
          cc: [],
          object: user_data
        })

      assert update.data["actor"] == user.ap_id
      assert update.data["to"] == [user.follower_address]
      assert update.data["object"]["id"] == user_data["id"]
      assert update.data["object"]["type"] == user_data["type"]
    end
  end

  test "it can fetch peertube videos" do
    {:ok, object} =
      ActivityPub.fetch_object_from_id(
        "https://peertube.moe/videos/watch/df5f464b-be8d-46fb-ad81-2d4c2d1630e3"
      )

    assert object
  end

  test "returned pinned statuses" do
    Pleroma.Config.put([:instance, :max_pinned_statuses], 3)
    user = insert(:user)

    {:ok, activity_one} = CommonAPI.post(user, %{"status" => "HI!!!"})
    {:ok, activity_two} = CommonAPI.post(user, %{"status" => "HI!!!"})
    {:ok, activity_three} = CommonAPI.post(user, %{"status" => "HI!!!"})

    CommonAPI.pin(activity_one.id, user)
    user = refresh_record(user)

    CommonAPI.pin(activity_two.id, user)
    user = refresh_record(user)

    CommonAPI.pin(activity_three.id, user)
    user = refresh_record(user)

    activities = ActivityPub.fetch_user_activities(user, nil, %{"pinned" => "true"})

    assert 3 = length(activities)
  end

  test "it can create a Flag activity" do
    reporter = insert(:user)
    target_account = insert(:user)
    {:ok, activity} = CommonAPI.post(target_account, %{"status" => "foobar"})
    context = Utils.generate_context_id()
    content = "foobar"

    reporter_ap_id = reporter.ap_id
    target_ap_id = target_account.ap_id
    activity_ap_id = activity.data["id"]

    assert {:ok, activity} =
             ActivityPub.flag(%{
               actor: reporter,
               context: context,
               account: target_account,
               statuses: [activity],
               content: content
             })

    assert %Activity{
             actor: ^reporter_ap_id,
             data: %{
               "type" => "Flag",
               "content" => ^content,
               "context" => ^context,
               "object" => [^target_ap_id, ^activity_ap_id]
             }
           } = activity
  end

  describe "publish_one/1" do
    test_with_mock "calls `Instances.set_reachable` on successful federation if `unreachable_since` is not specified",
                   Instances,
                   [:passthrough],
                   [] do
      actor = insert(:user)
      inbox = "http://200.site/users/nick1/inbox"

      assert {:ok, _} = ActivityPub.publish_one(%{inbox: inbox, json: "{}", actor: actor, id: 1})

      assert called(Instances.set_reachable(inbox))
    end

    test_with_mock "calls `Instances.set_reachable` on successful federation if `unreachable_since` is set",
                   Instances,
                   [:passthrough],
                   [] do
      actor = insert(:user)
      inbox = "http://200.site/users/nick1/inbox"

      assert {:ok, _} =
               ActivityPub.publish_one(%{
                 inbox: inbox,
                 json: "{}",
                 actor: actor,
                 id: 1,
                 unreachable_since: NaiveDateTime.utc_now()
               })

      assert called(Instances.set_reachable(inbox))
    end

    test_with_mock "does NOT call `Instances.set_reachable` on successful federation if `unreachable_since` is nil",
                   Instances,
                   [:passthrough],
                   [] do
      actor = insert(:user)
      inbox = "http://200.site/users/nick1/inbox"

      assert {:ok, _} =
               ActivityPub.publish_one(%{
                 inbox: inbox,
                 json: "{}",
                 actor: actor,
                 id: 1,
                 unreachable_since: nil
               })

      refute called(Instances.set_reachable(inbox))
    end

    test_with_mock "calls `Instances.set_unreachable` on target inbox on non-2xx HTTP response code",
                   Instances,
                   [:passthrough],
                   [] do
      actor = insert(:user)
      inbox = "http://404.site/users/nick1/inbox"

      assert {:error, _} =
               ActivityPub.publish_one(%{inbox: inbox, json: "{}", actor: actor, id: 1})

      assert called(Instances.set_unreachable(inbox))
    end

    test_with_mock "it calls `Instances.set_unreachable` on target inbox on request error of any kind",
                   Instances,
                   [:passthrough],
                   [] do
      actor = insert(:user)
      inbox = "http://connrefused.site/users/nick1/inbox"

      assert {:error, _} =
               ActivityPub.publish_one(%{inbox: inbox, json: "{}", actor: actor, id: 1})

      assert called(Instances.set_unreachable(inbox))
    end

    test_with_mock "does NOT call `Instances.set_unreachable` if target is reachable",
                   Instances,
                   [:passthrough],
                   [] do
      actor = insert(:user)
      inbox = "http://200.site/users/nick1/inbox"

      assert {:ok, _} = ActivityPub.publish_one(%{inbox: inbox, json: "{}", actor: actor, id: 1})

      refute called(Instances.set_unreachable(inbox))
    end

    test_with_mock "does NOT call `Instances.set_unreachable` if target instance has non-nil `unreachable_since`",
                   Instances,
                   [:passthrough],
                   [] do
      actor = insert(:user)
      inbox = "http://connrefused.site/users/nick1/inbox"

      assert {:error, _} =
               ActivityPub.publish_one(%{
                 inbox: inbox,
                 json: "{}",
                 actor: actor,
                 id: 1,
                 unreachable_since: NaiveDateTime.utc_now()
               })

      refute called(Instances.set_unreachable(inbox))
    end
  end

  def data_uri do
    File.read!("test/fixtures/avatar_data_uri")
  end
end