akkoma/lib/pleroma/instances/instance.ex
2020-09-07 08:40:52 +02:00

183 lines
4.9 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Instances.Instance do
@moduledoc "Instance."
alias Pleroma.Instances
alias Pleroma.Instances.Instance
alias Pleroma.Repo
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(:favicon_updated_at, :naive_datetime)
timestamps()
end
defdelegate host(url_or_host), to: Instances
def changeset(struct, params \\ %{}) do
struct
|> cast(params, [:host, :unreachable_since, :favicon, :favicon_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?(_), 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}
defp parse_datetime(datetime) when is_binary(datetime) do
NaiveDateTime.from_iso8601(datetime)
end
defp parse_datetime(datetime), do: datetime
def get_or_update_favicon(%URI{host: host} = instance_uri) do
existing_record = Repo.get_by(Instance, %{host: host})
now = NaiveDateTime.utc_now()
if existing_record && existing_record.favicon_updated_at &&
NaiveDateTime.diff(now, existing_record.favicon_updated_at) < 86_400 do
existing_record.favicon
else
favicon = scrape_favicon(instance_uri)
if existing_record do
existing_record
|> changeset(%{favicon: favicon, favicon_updated_at: now})
|> Repo.update()
else
%Instance{}
|> changeset(%{host: host, favicon: favicon, favicon_updated_at: now})
|> Repo.insert()
end
favicon
end
rescue
e ->
Logger.warn("Instance.get_or_update_favicon(\"#{host}\") error: #{inspect(e)}")
nil
end
defp scrape_favicon(%URI{} = instance_uri) do
try do
with {:ok, %Tesla.Env{body: html}} <-
Pleroma.HTTP.get(to_string(instance_uri), [{"accept", "text/html"}],
adapter: [pool: :media]
),
favicon_rel <-
html
|> Floki.parse_document!()
|> Floki.attribute("link[rel=icon]", "href")
|> List.first(),
favicon <- URI.merge(instance_uri, favicon_rel) |> to_string(),
true <- is_binary(favicon) do
favicon
else
_ -> nil
end
rescue
e ->
Logger.warn(
"Instance.scrape_favicon(\"#{to_string(instance_uri)}\") error: #{inspect(e)}"
)
nil
end
end
end