lbry-sdk/lbrynet/stream/reflector/client.py
2019-06-07 17:26:31 -04:00

121 lines
5 KiB
Python

import asyncio
import json
import logging
import typing
if typing.TYPE_CHECKING:
from lbrynet.blob.blob_manager import BlobManager
from lbrynet.stream.descriptor import StreamDescriptor
REFLECTOR_V1 = 0
REFLECTOR_V2 = 1
MAX_RESPONSE_SIZE = 2000000
log = logging.getLogger(__name__)
class StreamReflectorClient(asyncio.Protocol):
def __init__(self, blob_manager: 'BlobManager', descriptor: 'StreamDescriptor'):
self.loop = asyncio.get_event_loop()
self.transport: typing.Optional[asyncio.WriteTransport] = None
self.blob_manager = blob_manager
self.descriptor = descriptor
self.response_buff = b''
self.reflected_blobs = []
self.connected = asyncio.Event()
self.response_queue = asyncio.Queue(maxsize=1)
self.pending_request: typing.Optional[asyncio.Task] = None
def connection_made(self, transport):
self.transport = transport
log.debug("Connected to reflector")
self.connected.set()
def connection_lost(self, exc: typing.Optional[Exception]):
self.transport = None
self.connected.clear()
if self.reflected_blobs:
log.info("Finished sending reflector %i blobs", len(self.reflected_blobs))
def data_received(self, data):
if len(self.response_buff + (data or b'')) > MAX_RESPONSE_SIZE:
log.warning("response message to large from reflector server: %i bytes",
len(self.response_buff + (data or b'')))
self.response_buff = b''
self.transport.close()
return
self.response_buff += (data or b'')
try:
response = json.loads(self.response_buff.decode())
self.response_buff = b''
self.response_queue.put_nowait(response)
except ValueError:
if not data:
log.warning("got undecodable response from reflector server")
self.response_buff = b''
return
async def send_request(self, request_dict: typing.Dict):
msg = json.dumps(request_dict)
self.transport.write(msg.encode())
try:
self.pending_request = self.loop.create_task(self.response_queue.get())
return await self.pending_request
finally:
self.pending_request = None
async def send_handshake(self) -> None:
response_dict = await self.send_request({'version': REFLECTOR_V2})
if 'version' not in response_dict:
raise ValueError("Need protocol version number!")
server_version = int(response_dict['version'])
if server_version != REFLECTOR_V2:
raise ValueError("I can't handle protocol version {}!".format(server_version))
return
async def send_descriptor(self) -> typing.Tuple[bool, typing.List[str]]: # returns a list of needed blob hashes
sd_blob = self.blob_manager.get_blob(self.descriptor.sd_hash)
assert self.blob_manager.is_blob_verified(self.descriptor.sd_hash), "need to have sd blob to send at this point"
response = await self.send_request({
'sd_blob_hash': sd_blob.blob_hash,
'sd_blob_size': sd_blob.length
})
if 'send_sd_blob' not in response:
raise ValueError("I don't know whether to send the sd blob or not!")
needed = response.get('needed_blobs', [])
sent_sd = False
if response['send_sd_blob']:
await sd_blob.sendfile(self)
received = await self.response_queue.get()
if received.get('received_sd_blob'):
sent_sd = True
if not needed:
for blob in self.descriptor.blobs[:-1]:
if self.blob_manager.is_blob_verified(blob.blob_hash, blob.length):
needed.append(blob.blob_hash)
log.info("Sent reflector descriptor %s", sd_blob.blob_hash[:8])
self.reflected_blobs.append(sd_blob.blob_hash)
else:
log.warning("Reflector failed to receive descriptor %s", sd_blob.blob_hash[:8])
if needed:
log.info("Reflector needs %i blobs for %s", len(needed), sd_blob.blob_hash[:8])
return sent_sd, needed
async def send_blob(self, blob_hash: str):
assert self.blob_manager.is_blob_verified(blob_hash), "need to have a blob to send at this point"
blob = self.blob_manager.get_blob(blob_hash)
response = await self.send_request({
'blob_hash': blob.blob_hash,
'blob_size': blob.length
})
if 'send_blob' not in response:
raise ValueError("I don't know whether to send the blob or not!")
if response['send_blob']:
await blob.sendfile(self)
received = await self.response_queue.get()
if received.get('received_blob'):
self.reflected_blobs.append(blob.blob_hash)
log.info("Sent reflector blob %s", blob.blob_hash[:8])
else:
log.warning("Reflector failed to receive blob %s", blob.blob_hash[:8])