diff options
Diffstat (limited to 'lib/pleroma/migrators/support/base_migrator.ex')
| -rw-r--r-- | lib/pleroma/migrators/support/base_migrator.ex | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/lib/pleroma/migrators/support/base_migrator.ex b/lib/pleroma/migrators/support/base_migrator.ex new file mode 100644 index 000000000..1f8a5402b --- /dev/null +++ b/lib/pleroma/migrators/support/base_migrator.ex @@ -0,0 +1,210 @@ +# Pleroma: A lightweight social networking server +# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/> +# SPDX-License-Identifier: AGPL-3.0-only + +defmodule Pleroma.Migrators.Support.BaseMigrator do + @moduledoc """ + Base background migrator functionality. + """ + + @callback perform() :: any() + @callback retry_failed() :: any() + @callback feature_config_path() :: list(atom()) + @callback query() :: Ecto.Query.t() + @callback fault_rate_allowance() :: integer() | float() + + defmacro __using__(_opts) do + quote do + use GenServer + + require Logger + + import Ecto.Query + + alias __MODULE__.State + alias Pleroma.Config + alias Pleroma.Repo + + @behaviour Pleroma.Migrators.Support.BaseMigrator + + defdelegate data_migration(), to: State + defdelegate data_migration_id(), to: State + defdelegate state(), to: State + defdelegate persist_state(), to: State, as: :persist_to_db + defdelegate get_stat(key, value \\ nil), to: State, as: :get_data_key + defdelegate put_stat(key, value), to: State, as: :put_data_key + defdelegate increment_stat(key, increment), to: State, as: :increment_data_key + + @reg_name {:global, __MODULE__} + + def whereis, do: GenServer.whereis(@reg_name) + + def start_link(_) do + case whereis() do + nil -> + GenServer.start_link(__MODULE__, nil, name: @reg_name) + + pid -> + {:ok, pid} + end + end + + @impl true + def init(_) do + {:ok, nil, {:continue, :init_state}} + end + + @impl true + def handle_continue(:init_state, _state) do + {:ok, _} = State.start_link(nil) + + data_migration = data_migration() + manual_migrations = Config.get([:instance, :manual_data_migrations], []) + + cond do + Config.get(:env) == :test -> + update_status(:noop) + + is_nil(data_migration) -> + message = "Data migration does not exist." + update_status(:failed, message) + Logger.error("#{__MODULE__}: #{message}") + + data_migration.state == :manual or data_migration.name in manual_migrations -> + message = "Data migration is in manual execution or manual fix mode." + update_status(:manual, message) + Logger.warn("#{__MODULE__}: #{message}") + + data_migration.state == :complete -> + on_complete(data_migration) + + true -> + send(self(), :perform) + end + + {:noreply, nil} + end + + @impl true + def handle_info(:perform, state) do + State.reinit() + + update_status(:running) + put_stat(:iteration_processed_count, 0) + put_stat(:started_at, NaiveDateTime.utc_now()) + + perform() + + fault_rate = fault_rate() + put_stat(:fault_rate, fault_rate) + fault_rate_allowance = fault_rate_allowance() + + cond do + fault_rate == 0 -> + set_complete() + + is_float(fault_rate) and fault_rate <= fault_rate_allowance -> + message = """ + Done with fault rate of #{fault_rate} which doesn't exceed #{fault_rate_allowance}. + Putting data migration to manual fix mode. Try running `#{__MODULE__}.retry_failed/0`. + """ + + Logger.warn("#{__MODULE__}: #{message}") + update_status(:manual, message) + on_complete(data_migration()) + + true -> + message = "Too many failures. Try running `#{__MODULE__}.retry_failed/0`." + Logger.error("#{__MODULE__}: #{message}") + update_status(:failed, message) + end + + persist_state() + {:noreply, state} + end + + defp on_complete(data_migration) do + if data_migration.feature_lock || feature_state() == :disabled do + Logger.warn( + "#{__MODULE__}: migration complete but feature is locked; consider enabling." + ) + + :noop + else + Config.put(feature_config_path(), :enabled) + :ok + end + end + + @doc "Approximate count for current iteration (including processed records count)" + def count(force \\ false, timeout \\ :infinity) do + stored_count = get_stat(:count) + + if stored_count && !force do + stored_count + else + processed_count = get_stat(:processed_count, 0) + max_processed_id = get_stat(:max_processed_id, 0) + query = where(query(), [entity], entity.id > ^max_processed_id) + + count = Repo.aggregate(query, :count, :id, timeout: timeout) + processed_count + put_stat(:count, count) + persist_state() + + count + end + end + + def failures_count do + with {:ok, %{rows: [[count]]}} <- + Repo.query( + "SELECT COUNT(record_id) FROM data_migration_failed_ids WHERE data_migration_id = $1;", + [data_migration_id()] + ) do + count + end + end + + def feature_state, do: Config.get(feature_config_path()) + + def force_continue do + send(whereis(), :perform) + end + + def force_restart do + :ok = State.reset() + force_continue() + end + + def set_complete do + update_status(:complete) + persist_state() + on_complete(data_migration()) + end + + defp update_status(status, message \\ nil) do + put_stat(:state, status) + put_stat(:message, message) + end + + defp fault_rate do + with failures_count when is_integer(failures_count) <- failures_count() do + failures_count / Enum.max([get_stat(:affected_count, 0), 1]) + else + _ -> :error + end + end + + defp records_per_second do + get_stat(:iteration_processed_count, 0) / Enum.max([running_time(), 1]) + end + + defp running_time do + NaiveDateTime.diff( + NaiveDateTime.utc_now(), + get_stat(:started_at, NaiveDateTime.utc_now()) + ) + end + end + end +end |