forked from mirrors/akkoma
137 lines
3.8 KiB
Elixir
137 lines
3.8 KiB
Elixir
# Pleroma: A lightweight social networking server
|
|
# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
|
|
# SPDX-License-Identifier: AGPL-3.0-only
|
|
|
|
defmodule Pleroma.Plugs.Cache do
|
|
@moduledoc """
|
|
Caches successful GET responses.
|
|
|
|
To enable the cache add the plug to a router pipeline or controller:
|
|
|
|
plug(Pleroma.Plugs.Cache)
|
|
|
|
## Configuration
|
|
|
|
To configure the plug you need to pass settings as the second argument to the `plug/2` macro:
|
|
|
|
plug(Pleroma.Plugs.Cache, [ttl: nil, query_params: true])
|
|
|
|
Available options:
|
|
|
|
- `ttl`: An expiration time (time-to-live). This value should be in milliseconds or `nil` to disable expiration. Defaults to `nil`.
|
|
- `query_params`: Take URL query string into account (`true`), ignore it (`false`) or limit to specific params only (list). Defaults to `true`.
|
|
- `tracking_fun`: A function that is called on successfull responses, no matter if the request is cached or not. It should accept a conn as the first argument and the value assigned to `tracking_fun_data` as the second.
|
|
|
|
Additionally, you can overwrite the TTL inside a controller action by assigning `cache_ttl` to the connection struct:
|
|
|
|
def index(conn, _params) do
|
|
ttl = 60_000 # one minute
|
|
|
|
conn
|
|
|> assign(:cache_ttl, ttl)
|
|
|> render("index.html")
|
|
end
|
|
|
|
"""
|
|
|
|
import Phoenix.Controller, only: [current_path: 1, json: 2]
|
|
import Plug.Conn
|
|
|
|
@behaviour Plug
|
|
|
|
@defaults %{ttl: nil, query_params: true}
|
|
|
|
@impl true
|
|
def init([]), do: @defaults
|
|
|
|
def init(opts) do
|
|
opts = Map.new(opts)
|
|
Map.merge(@defaults, opts)
|
|
end
|
|
|
|
@impl true
|
|
def call(%{method: "GET"} = conn, opts) do
|
|
key = cache_key(conn, opts)
|
|
|
|
case Cachex.get(:web_resp_cache, key) do
|
|
{:ok, nil} ->
|
|
cache_resp(conn, opts)
|
|
|
|
{:ok, {content_type, body, tracking_fun_data}} ->
|
|
conn = opts.tracking_fun.(conn, tracking_fun_data)
|
|
|
|
send_cached(conn, {content_type, body})
|
|
|
|
{:ok, record} ->
|
|
send_cached(conn, record)
|
|
|
|
{atom, message} when atom in [:ignore, :error] ->
|
|
render_error(conn, message)
|
|
end
|
|
end
|
|
|
|
def call(conn, _), do: conn
|
|
|
|
# full path including query params
|
|
defp cache_key(conn, %{query_params: true}), do: current_path(conn)
|
|
|
|
# request path without query params
|
|
defp cache_key(conn, %{query_params: false}), do: conn.request_path
|
|
|
|
# request path with specific query params
|
|
defp cache_key(conn, %{query_params: query_params}) when is_list(query_params) do
|
|
query_string =
|
|
conn.params
|
|
|> Map.take(query_params)
|
|
|> URI.encode_query()
|
|
|
|
conn.request_path <> "?" <> query_string
|
|
end
|
|
|
|
defp cache_resp(conn, opts) do
|
|
register_before_send(conn, fn
|
|
%{status: 200, resp_body: body} = conn ->
|
|
ttl = Map.get(conn.assigns, :cache_ttl, opts.ttl)
|
|
key = cache_key(conn, opts)
|
|
content_type = content_type(conn)
|
|
|
|
conn =
|
|
unless opts[:tracking_fun] do
|
|
Cachex.put(:web_resp_cache, key, {content_type, body}, ttl: ttl)
|
|
conn
|
|
else
|
|
tracking_fun_data = Map.get(conn.assigns, :tracking_fun_data, nil)
|
|
Cachex.put(:web_resp_cache, key, {content_type, body, tracking_fun_data}, ttl: ttl)
|
|
|
|
opts.tracking_fun.(conn, tracking_fun_data)
|
|
end
|
|
|
|
put_resp_header(conn, "x-cache", "MISS from Pleroma")
|
|
|
|
conn ->
|
|
conn
|
|
end)
|
|
end
|
|
|
|
defp content_type(conn) do
|
|
conn
|
|
|> Plug.Conn.get_resp_header("content-type")
|
|
|> hd()
|
|
end
|
|
|
|
defp send_cached(conn, {content_type, body}) do
|
|
conn
|
|
|> put_resp_content_type(content_type, nil)
|
|
|> put_resp_header("x-cache", "HIT from Pleroma")
|
|
|> send_resp(:ok, body)
|
|
|> halt()
|
|
end
|
|
|
|
defp render_error(conn, message) do
|
|
conn
|
|
|> put_status(:internal_server_error)
|
|
|> json(%{error: message})
|
|
|> halt()
|
|
end
|
|
end
|