File size: 4,298 Bytes
2720e84
31d7b86
2720e84
 
 
 
 
 
 
 
 
 
 
31d7b86
2720e84
 
 
 
 
 
 
 
 
 
 
 
 
 
31d7b86
 
 
 
 
 
 
 
 
 
 
 
2720e84
 
 
 
 
 
 
 
 
 
 
31d7b86
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2720e84
 
 
 
 
 
 
 
 
 
 
 
 
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
'''CRDT is used to synchronize workspace state for backend and frontend(s).'''
import asyncio
import contextlib
import fastapi
import os.path
import pycrdt
import pycrdt_websocket

import pycrdt_websocket.ystore

router = fastapi.APIRouter()

def ws_exception_handler(exception, log):
    print('exception', exception)
    log.exception(exception)
    return True

class WebsocketServer(pycrdt_websocket.WebsocketServer):
    async def init_room(self, name):
        ystore = pycrdt_websocket.ystore.FileYStore(f'crdt_data/{name}.crdt')
        ydoc = pycrdt.Doc()
        ydoc['workspace'] = ws = pycrdt.Map()
        # Replay updates from the store.
        try:
            for update, timestamp in [(item[0], item[-1]) async for item in ystore.read()]:
                ydoc.apply_update(update)
        except pycrdt_websocket.ystore.YDocNotFound:
            pass
        if 'nodes' not in ws:
            ws['nodes'] = pycrdt.Array()
        if 'edges' not in ws:
            ws['edges'] = pycrdt.Array()
        if 'env' not in ws:
            ws['env'] = 'unset'
        room = pycrdt_websocket.YRoom(ystore=ystore, ydoc=ydoc)
        room.ws = ws
        def on_change(changes):
            asyncio.create_task(workspace_changed(changes, ws))
        ws.observe_deep(on_change)
        return room

    async def get_room(self, name: str) -> pycrdt_websocket.YRoom:
        if name not in self.rooms:
            self.rooms[name] = await self.init_room(name)
        room = self.rooms[name]
        await self.start_room(room)
        return room

websocket_server = WebsocketServer(exception_handler=ws_exception_handler, auto_clean_rooms=False)
asgi_server = pycrdt_websocket.ASGIServer(websocket_server)

last_ws_input = None
def clean_input(ws_pyd):
    for node in ws_pyd.nodes:
        node.data.display = None
        node.position.x = 0
        node.position.y = 0
        if node.model_extra:
            for key in list(node.model_extra.keys()):
                delattr(node, key)

def crdt_update(crdt_obj, python_obj):
    if isinstance(python_obj, dict):
        for key, value in python_obj.items():
            if isinstance(value, dict):
                if crdt_obj.get(key) is None:
                    crdt_obj[key] = pycrdt.Map()
                crdt_update(crdt_obj[key], value)
            elif isinstance(value, list):
                if crdt_obj.get(key) is None:
                    crdt_obj[key] = pycrdt.Array()
                crdt_update(crdt_obj[key], value)
            else:
                print('set', key, value)
                crdt_obj[key] = value
    elif isinstance(python_obj, list):
        for i, value in enumerate(python_obj):
            if isinstance(value, dict):
                if i >= len(crdt_obj):
                    crdt_obj.append(pycrdt.Map())
                crdt_update(crdt_obj[i], value)
            elif isinstance(value, list):
                if i >= len(crdt_obj):
                    crdt_obj.append(pycrdt.Array())
                crdt_update(crdt_obj[i], value)
            else:
                if i >= len(crdt_obj):
                    crdt_obj.append(value)
                else:
                    print('set', i, value)
                    crdt_obj[i] = value
    else:
        raise ValueError('Invalid type:', python_obj)

async def workspace_changed(e, ws_crdt):
    global last_ws_input
    from . import workspace
    ws_pyd = workspace.Workspace.model_validate(ws_crdt.to_py())
    clean_input(ws_pyd)
    if ws_pyd == last_ws_input:
        return
    print('ws changed')
    last_ws_input = ws_pyd.model_copy(deep=True)
    workspace.execute(ws_pyd)
    for nc, np in zip(ws_crdt['nodes'], ws_pyd.nodes):
        if 'data' not in nc:
            nc['data'] = pycrdt.Map()
        # Display is added as an opaque Box.
        nc['data']['display'] = np.data.display

@contextlib.asynccontextmanager
async def lifespan(app):
    async with websocket_server:
        yield

def sanitize_path(path):
    return os.path.relpath(os.path.normpath(os.path.join("/", path)), "/")

@router.websocket("/ws/crdt/{room_name}")
async def crdt_websocket(websocket: fastapi.WebSocket, room_name: str):
    room_name = sanitize_path(room_name)
    await asgi_server({'path': room_name}, websocket._receive, websocket._send)