summaryrefslogtreecommitdiff
path: root/backend/plugin.py
blob: 04ba285de97c0f33bcfdbc0d5d76f2a6d16752c8 (plain)
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
import multiprocessing
from asyncio import (Lock, get_event_loop, new_event_loop,
                     open_unix_connection, set_event_loop, sleep,
                     start_unix_server)
from concurrent.futures import ProcessPoolExecutor
from importlib.util import module_from_spec, spec_from_file_location
from json import dumps, load, loads
from os import path, setgid, setuid
from signal import SIGINT, signal
from sys import exit
from time import time

multiprocessing.set_start_method("fork")

class PluginWrapper:
    def __init__(self, file, plugin_directory, plugin_path) -> None:
        self.file = file
        self.plugin_directory = plugin_directory
        self.reader = None
        self.writer = None
        self.socket_addr = f"/tmp/plugin_socket_{time()}"
        self.method_call_lock = Lock()

        self.version = None

        json = load(open(path.join(plugin_path, plugin_directory, "plugin.json"), "r"))
        if path.isfile(path.join(plugin_path, plugin_directory, "package.json")):
            package_json = load(open(path.join(plugin_path, plugin_directory, "package.json"), "r"))
            self.version = package_json["version"]


        self.legacy = False
        self.main_view_html = json["main_view_html"] if "main_view_html" in json else ""
        self.tile_view_html = json["tile_view_html"] if "tile_view_html" in json else ""
        self.legacy = self.main_view_html or self.tile_view_html

        self.name = json["name"]
        self.author = json["author"]
        self.flags = json["flags"]

        self.passive = not path.isfile(self.file)

    def __str__(self) -> str:
        return self.name

    def _init(self):
        signal(SIGINT, lambda s, f: exit(0))

        set_event_loop(new_event_loop())
        if self.passive:
            return
        setgid(0 if "root" in self.flags else 1000)
        setuid(0 if "root" in self.flags else 1000)
        spec = spec_from_file_location("_", self.file)
        module = module_from_spec(spec)
        spec.loader.exec_module(module)
        self.Plugin = module.Plugin

        if hasattr(self.Plugin, "_main"):
            get_event_loop().create_task(self.Plugin._main(self.Plugin))
        get_event_loop().create_task(self._setup_socket())
        get_event_loop().run_forever()

    async def _setup_socket(self):
        self.socket = await start_unix_server(self._listen_for_method_call, path=self.socket_addr)

    async def _listen_for_method_call(self, reader, writer):
        while True:
            data = loads((await reader.readline()).decode("utf-8"))
            if "stop" in data:
                get_event_loop().stop()
                while get_event_loop().is_running():
                    await sleep(0)
                get_event_loop().close()
                return
            d = {"res": None, "success": True}
            try:
                d["res"] = await getattr(self.Plugin, data["method"])(self.Plugin, **data["args"])
            except Exception as e:
                d["res"] = str(e)
                d["success"] = False
            finally:
                writer.write((dumps(d)+"\n").encode("utf-8"))
                await writer.drain()

    async def _open_socket_if_not_exists(self):
        if not self.reader:
            retries = 0
            while retries < 10:
                try:
                    self.reader, self.writer = await open_unix_connection(self.socket_addr)
                    return True
                except:
                    await sleep(2)
                    retries += 1
            return False
        else:
            return True

    def start(self):
        if self.passive:
            return self
        multiprocessing.Process(target=self._init).start()
        return self

    def stop(self):
        if self.passive:
            return
        async def _(self):
            if await self._open_socket_if_not_exists():
                self.writer.write((dumps({"stop": True})+"\n").encode("utf-8"))
                await self.writer.drain()
                self.writer.close()
        get_event_loop().create_task(_(self))

    async def execute_method(self, method_name, kwargs):
        if self.passive:
            raise RuntimeError("This plugin is passive (aka does not implement main.py)")
        async with self.method_call_lock:
            if await self._open_socket_if_not_exists():
                self.writer.write(
                    (dumps({"method": method_name, "args": kwargs})+"\n").encode("utf-8"))
                await self.writer.drain()
                res = loads((await self.reader.readline()).decode("utf-8"))
                if not res["success"]:
                    raise Exception(res["res"])
                return res["res"]