akkoma/lib/pleroma/instances/instance.ex

319 lines
8.9 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Instances.Instance do
@moduledoc "Instance."
@cachex Pleroma.Config.get([:cachex, :provider], Cachex)
alias Pleroma.Instances
alias Pleroma.Instances.Instance
alias Pleroma.Repo
alias Pleroma.User
alias Pleroma.Workers.BackgroundWorker
use Ecto.Schema
import Ecto.Query
import Ecto.Changeset
require Logger
schema "instances" do
field(:host, :string)
field(:unreachable_since, :naive_datetime_usec)
field(:favicon, :string)
field(:metadata_updated_at, :naive_datetime)
field(:nodeinfo, :map, default: %{})
timestamps()
end
defdelegate host(url_or_host), to: Instances
def changeset(struct, params \\ %{}) do
struct
|> cast(params, [:host, :unreachable_since, :favicon, :nodeinfo, :metadata_updated_at])
|> validate_required([:host])
|> unique_constraint(:host)
end
def filter_reachable([]), do: %{}
def filter_reachable(urls_or_hosts) when is_list(urls_or_hosts) do
hosts =
urls_or_hosts
|> Enum.map(&(&1 && host(&1)))
|> Enum.filter(&(to_string(&1) != ""))
unreachable_since_by_host =
Repo.all(
from(i in Instance,
where: i.host in ^hosts,
select: {i.host, i.unreachable_since}
)
)
|> Map.new(& &1)
reachability_datetime_threshold = Instances.reachability_datetime_threshold()
for entry <- Enum.filter(urls_or_hosts, &is_binary/1) do
host = host(entry)
unreachable_since = unreachable_since_by_host[host]
if !unreachable_since ||
NaiveDateTime.compare(unreachable_since, reachability_datetime_threshold) == :gt do
{entry, unreachable_since}
end
end
|> Enum.filter(& &1)
|> Map.new(& &1)
end
def reachable?(url_or_host) when is_binary(url_or_host) do
!Repo.one(
from(i in Instance,
where:
i.host == ^host(url_or_host) and
i.unreachable_since <= ^Instances.reachability_datetime_threshold(),
select: true
)
)
end
def reachable?(url_or_host) when is_binary(url_or_host), do: true
def set_reachable(url_or_host) when is_binary(url_or_host) do
with host <- host(url_or_host),
%Instance{} = existing_record <- Repo.get_by(Instance, %{host: host}) do
{:ok, _instance} =
existing_record
|> changeset(%{unreachable_since: nil})
|> Repo.update()
end
end
def set_reachable(_), do: {:error, nil}
def set_unreachable(url_or_host, unreachable_since \\ nil)
def set_unreachable(url_or_host, unreachable_since) when is_binary(url_or_host) do
unreachable_since = parse_datetime(unreachable_since) || NaiveDateTime.utc_now()
host = host(url_or_host)
existing_record = Repo.get_by(Instance, %{host: host})
changes = %{unreachable_since: unreachable_since}
cond do
is_nil(existing_record) ->
%Instance{}
|> changeset(Map.put(changes, :host, host))
|> Repo.insert()
existing_record.unreachable_since &&
NaiveDateTime.compare(existing_record.unreachable_since, unreachable_since) != :gt ->
{:ok, existing_record}
true ->
existing_record
|> changeset(changes)
|> Repo.update()
end
end
def set_unreachable(_, _), do: {:error, nil}
def get_consistently_unreachable do
reachability_datetime_threshold = Instances.reachability_datetime_threshold()
from(i in Instance,
where: ^reachability_datetime_threshold > i.unreachable_since,
order_by: i.unreachable_since,
select: {i.host, i.unreachable_since}
)
|> Repo.all()
end
defp parse_datetime(datetime) when is_binary(datetime) do
NaiveDateTime.from_iso8601(datetime)
end
defp parse_datetime(datetime), do: datetime
def needs_update(nil), do: true
def needs_update(%Instance{metadata_updated_at: nil}), do: true
def needs_update(%Instance{metadata_updated_at: metadata_updated_at}) do
now = NaiveDateTime.utc_now()
NaiveDateTime.diff(now, metadata_updated_at) > 86_400
end
def local do
%Instance{
host: Pleroma.Web.Endpoint.host(),
favicon: Pleroma.Web.Endpoint.url() <> "/favicon.png",
nodeinfo: Pleroma.Web.Nodeinfo.NodeinfoController.raw_nodeinfo()
}
end
def update_metadata(%URI{host: host} = uri) do
Logger.debug("Checking metadata for #{host}")
existing_record = Repo.get_by(Instance, %{host: host})
if reachable?(host) do
do_update_metadata(uri, existing_record)
else
{:discard, :unreachable}
end
end
defp do_update_metadata(%URI{host: host} = uri, existing_record) do
if existing_record do
if needs_update(existing_record) do
Logger.info("Updating metadata for #{host}")
favicon = scrape_favicon(uri)
nodeinfo = scrape_nodeinfo(uri)
existing_record
|> changeset(%{
host: host,
favicon: favicon,
nodeinfo: nodeinfo,
metadata_updated_at: NaiveDateTime.utc_now()
})
|> Repo.update()
else
{:discard, "Does not require update"}
end
else
favicon = scrape_favicon(uri)
nodeinfo = scrape_nodeinfo(uri)
Logger.info("Creating metadata for #{host}")
%Instance{}
|> changeset(%{
host: host,
favicon: favicon,
nodeinfo: nodeinfo,
metadata_updated_at: NaiveDateTime.utc_now()
})
|> Repo.insert()
end
end
def get_favicon(%URI{host: host}) do
existing_record = Repo.get_by(Instance, %{host: host})
if existing_record do
existing_record.favicon
else
nil
end
end
defp scrape_nodeinfo(%URI{} = instance_uri) do
with true <- Pleroma.Config.get([:instances_nodeinfo, :enabled]),
{_, true} <- {:reachable, reachable?(instance_uri.host)},
{:ok, %Tesla.Env{status: 200, body: body}} <-
Tesla.get(
"https://#{instance_uri.host}/.well-known/nodeinfo",
headers: [{"Accept", "application/json"}]
),
{:ok, json} <- Jason.decode(body),
{:ok, %{"links" => links}} <- {:ok, json},
{:ok, %{"href" => href}} <-
{:ok,
Enum.find(links, &(&1["rel"] == "http://nodeinfo.diaspora.software/ns/schema/2.0"))},
{:ok, %Tesla.Env{body: data}} <-
Pleroma.HTTP.get(href, [{"accept", "application/json"}], []),
{:length, true} <- {:length, String.length(data) < 50_000},
{:ok, nodeinfo} <- Jason.decode(data) do
nodeinfo
else
{:reachable, false} ->
Logger.debug(
"Instance.scrape_nodeinfo(\"#{to_string(instance_uri)}\") ignored unreachable host"
)
nil
{:length, false} ->
Logger.debug(
"Instance.scrape_nodeinfo(\"#{to_string(instance_uri)}\") ignored too long body"
)
nil
_ ->
nil
end
end
defp scrape_favicon(%URI{} = instance_uri) do
with true <- Pleroma.Config.get([:instances_favicons, :enabled]),
{_, true} <- {:reachable, reachable?(instance_uri.host)},
{:ok, %Tesla.Env{body: html}} <-
Pleroma.HTTP.get(to_string(instance_uri), [{"accept", "text/html"}], []),
{_, [favicon_rel | _]} when is_binary(favicon_rel) <-
{:parse, html |> Floki.parse_document!() |> Floki.attribute("link[rel=icon]", "href")},
{_, favicon} when is_binary(favicon) <-
{:merge, URI.merge(instance_uri, favicon_rel) |> to_string()},
{:length, true} <- {:length, String.length(favicon) < 255} do
favicon
else
{:reachable, false} ->
Logger.debug(
"Instance.scrape_favicon(\"#{to_string(instance_uri)}\") ignored unreachable host"
)
nil
_ ->
nil
end
end
@doc """
Deletes all users from an instance in a background task, thus also deleting
all of those users' activities and notifications.
"""
def delete_users_and_activities(host) when is_binary(host) do
BackgroundWorker.enqueue("delete_instance", %{"host" => host})
end
def perform(:delete_instance, host) when is_binary(host) do
User.Query.build(%{nickname: "@#{host}"})
|> Repo.chunk_stream(100, :batches)
|> Stream.each(fn users ->
users
|> Enum.each(fn user ->
User.perform(:delete, user)
end)
end)
|> Stream.run()
end
def get_by_url(url_or_host) do
url = host(url_or_host)
Repo.get_by(Instance, host: url)
end
def get_cached_by_url(url_or_host) do
url = host(url_or_host)
if url == Pleroma.Web.Endpoint.host() do
{:ok, local()}
else
@cachex.fetch!(:instances_cache, "instances:#{url}", fn _ ->
with %Instance{} = instance <- get_by_url(url) do
{:commit, {:ok, instance}}
else
_ -> {:ignore, nil}
end
end)
end
end
end