1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
|
# Pleroma: A lightweight social networking server
# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Gun.Connections do
use GenServer
@type domain :: String.t()
@type conn :: Gun.Conn.t()
@type t :: %__MODULE__{
conns: %{domain() => conn()}
}
defstruct conns: %{}
def start_link(name \\ __MODULE__) do
if Application.get_env(:tesla, :adapter) == Tesla.Adapter.Gun do
GenServer.start_link(__MODULE__, [], name: name)
else
:ignore
end
end
@impl true
def init(_) do
{:ok, %__MODULE__{conns: %{}}}
end
@spec get_conn(String.t(), keyword(), atom()) :: pid()
def get_conn(url, opts \\ [], name \\ __MODULE__) do
opts = Enum.into(opts, %{})
uri = URI.parse(url)
opts =
if uri.scheme == "https" and uri.port != 443,
do: Map.put(opts, :transport, :tls),
else: opts
GenServer.call(
name,
{:conn, %{opts: opts, uri: uri}}
)
end
# TODO: only for testing, add this parameter to the config
@spec try_to_get_gun_conn(String.t(), keyword(), atom()) :: nil | pid()
def try_to_get_gun_conn(url, opts \\ [], name \\ __MODULE__),
do: try_to_get_gun_conn(url, opts, name, 0)
@spec try_to_get_gun_conn(String.t(), keyword(), atom(), pos_integer()) :: nil | pid()
def try_to_get_gun_conn(_url, _, _, 3), do: nil
def try_to_get_gun_conn(url, opts, name, acc) do
case Pleroma.Gun.Connections.get_conn(url, opts, name) do
nil -> try_to_get_gun_conn(url, acc + 1)
conn -> conn
end
end
@spec alive?(atom()) :: boolean()
def alive?(name \\ __MODULE__) do
pid = Process.whereis(name)
if pid, do: Process.alive?(pid), else: false
end
@spec get_state(atom()) :: t()
def get_state(name \\ __MODULE__) do
GenServer.call(name, {:state})
end
@impl true
def handle_call({:conn, %{opts: opts, uri: uri}}, from, state) do
key = compose_key(uri)
case state.conns[key] do
%{conn: conn, state: conn_state} when conn_state == :up ->
{:reply, conn, state}
%{state: conn_state, waiting_pids: pids} when conn_state in [:open, :down] ->
state = put_in(state.conns[key].waiting_pids, [from | pids])
{:noreply, state}
nil ->
{:ok, conn} = Pleroma.Gun.API.open(to_charlist(uri.host), uri.port, opts)
state =
put_in(state.conns[key], %Pleroma.Gun.Conn{
conn: conn,
waiting_pids: [from],
protocol: String.to_atom(uri.scheme)
})
{:noreply, state}
end
end
@impl true
def handle_call({:state}, _from, state), do: {:reply, state, state}
@impl true
def handle_info({:gun_up, conn_pid, _protocol}, state) do
{key, conn} = find_conn(state.conns, conn_pid)
# Send to all waiting processes connection pid
Enum.each(conn.waiting_pids, fn waiting_pid -> GenServer.reply(waiting_pid, conn_pid) end)
# Update state of the current connection and set waiting_pids to empty list
state = put_in(state.conns[key], %{conn | state: :up, waiting_pids: []})
{:noreply, state}
end
@impl true
# Do we need to do something with killed & unprocessed references?
def handle_info({:gun_down, conn_pid, _protocol, _reason, _killed, _unprocessed}, state) do
{key, conn} = find_conn(state.conns, conn_pid)
# We don't want to block requests to GenServer if gun send down message, return nil, so we can make some retries, while connection is not up
Enum.each(conn.waiting_pids, fn waiting_pid -> GenServer.reply(waiting_pid, nil) end)
state = put_in(state.conns[key].state, :down)
{:noreply, state}
end
defp compose_key(uri), do: uri.host <> ":" <> to_string(uri.port)
defp find_conn(conns, conn_pid) do
Enum.find(conns, fn {key, conn} ->
protocol = if String.ends_with?(key, ":443"), do: :https, else: :http
conn.conn == conn_pid and conn.protocol == protocol
end)
end
end
|
