lbry-sdk/lbrynet/blob_exchange/serialization.py
2019-01-24 00:13:15 -05:00

290 lines
9 KiB
Python

import typing
import json
import logging
log = logging.getLogger(__name__)
class BlobMessage:
key = ''
def to_dict(self) -> typing.Dict:
raise NotImplementedError()
class BlobPriceRequest(BlobMessage):
key = 'blob_data_payment_rate'
def __init__(self, blob_data_payment_rate: float, **kwargs) -> None:
self.blob_data_payment_rate = blob_data_payment_rate
def to_dict(self) -> typing.Dict:
return {
self.key: self.blob_data_payment_rate
}
class BlobPriceResponse(BlobMessage):
key = 'blob_data_payment_rate'
rate_accepted = 'RATE_ACCEPTED'
rate_too_low = 'RATE_TOO_LOW'
rate_unset = 'RATE_UNSET'
def __init__(self, blob_data_payment_rate: str, **kwargs) -> None:
if blob_data_payment_rate not in (self.rate_accepted, self.rate_too_low, self.rate_unset):
raise ValueError(blob_data_payment_rate)
self.blob_data_payment_rate = blob_data_payment_rate
def to_dict(self) -> typing.Dict:
return {
self.key: self.blob_data_payment_rate
}
class BlobAvailabilityRequest(BlobMessage):
key = 'requested_blobs'
def __init__(self, requested_blobs: typing.List[str], lbrycrd_address: typing.Optional[bool] = True,
**kwargs) -> None:
assert len(requested_blobs)
self.requested_blobs = requested_blobs
self.lbrycrd_address = lbrycrd_address
def to_dict(self) -> typing.Dict:
return {
self.key: self.requested_blobs,
'lbrycrd_address': self.lbrycrd_address
}
class BlobAvailabilityResponse(BlobMessage):
key = 'available_blobs'
def __init__(self, available_blobs: typing.List[str], lbrycrd_address: typing.Optional[str] = True,
**kwargs) -> None:
self.available_blobs = available_blobs
self.lbrycrd_address = lbrycrd_address
def to_dict(self) -> typing.Dict:
d = {
self.key: self.available_blobs
}
if self.lbrycrd_address:
d['lbrycrd_address'] = self.lbrycrd_address
return d
class BlobDownloadRequest(BlobMessage):
key = 'requested_blob'
def __init__(self, requested_blob: str, **kwargs) -> None:
self.requested_blob = requested_blob
def to_dict(self) -> typing.Dict:
return {
self.key: self.requested_blob
}
class BlobDownloadResponse(BlobMessage):
key = 'incoming_blob'
def __init__(self, **response: typing.Dict) -> None:
incoming_blob = response[self.key]
self.error = None
self.incoming_blob = None
if 'error' in incoming_blob:
self.error = incoming_blob['error']
else:
self.incoming_blob = {'blob_hash': incoming_blob['blob_hash'], 'length': incoming_blob['length']}
self.length = None if not self.incoming_blob else self.incoming_blob['length']
self.blob_hash = None if not self.incoming_blob else self.incoming_blob['blob_hash']
def to_dict(self) -> typing.Dict:
return {
self.key if not self.error else 'error': self.incoming_blob or self.error,
}
class BlobPaymentAddressRequest(BlobMessage):
key = 'lbrycrd_address'
def __init__(self, lbrycrd_address: str, **kwargs) -> None:
self.lbrycrd_address = lbrycrd_address
def to_dict(self) -> typing.Dict:
return {
self.key: self.lbrycrd_address
}
class BlobPaymentAddressResponse(BlobPaymentAddressRequest):
pass
class BlobErrorResponse(BlobMessage):
key = 'error'
def __init__(self, error: str, **kwargs) -> None:
self.error = error
def to_dict(self) -> typing.Dict:
return {
self.key: self.error
}
blob_request_types = typing.Union[BlobPriceRequest, BlobAvailabilityRequest, BlobDownloadRequest,
BlobPaymentAddressRequest]
blob_response_types = typing.Union[BlobPriceResponse, BlobAvailabilityResponse, BlobDownloadResponse,
BlobErrorResponse, BlobPaymentAddressResponse]
def _parse_blob_response(response_msg: bytes) -> typing.Tuple[typing.Optional[typing.Dict], bytes]:
# scenarios:
# <json>
# <blob bytes>
# <json><blob bytes>
extra_data = b''
response = None
curr_pos = 0
while True:
next_close_paren = response_msg.find(b'}', curr_pos)
if next_close_paren == -1:
break
curr_pos = next_close_paren + 1
try:
response = json.loads(response_msg[:curr_pos])
if not isinstance(response, dict):
raise ValueError()
for key in response.keys():
if key not in [
BlobPaymentAddressResponse.key,
BlobAvailabilityResponse.key,
BlobPriceResponse.key,
BlobDownloadResponse.key]:
raise ValueError()
extra_data = response_msg[curr_pos:]
break
except ValueError:
response = None
if response is None:
extra_data = response_msg
return response, extra_data
class BlobRequest:
def __init__(self, requests: typing.List[blob_request_types]) -> None:
self.requests = requests
def to_dict(self):
d = {}
for request in self.requests:
d.update(request.to_dict())
return d
def _get_request(self, request_type: blob_request_types):
request = tuple(filter(lambda r: type(r) == request_type, self.requests))
if request:
return request[0]
def get_availability_request(self) -> typing.Optional[BlobAvailabilityRequest]:
response = self._get_request(BlobAvailabilityRequest)
if response:
return response
def get_price_request(self) -> typing.Optional[BlobPriceRequest]:
response = self._get_request(BlobPriceRequest)
if response:
return response
def get_blob_request(self) -> typing.Optional[BlobDownloadRequest]:
response = self._get_request(BlobDownloadRequest)
if response:
return response
def get_address_request(self) -> typing.Optional[BlobPaymentAddressRequest]:
response = self._get_request(BlobPaymentAddressRequest)
if response:
return response
def serialize(self) -> bytes:
return json.dumps(self.to_dict()).encode()
@classmethod
def deserialize(cls, data: bytes) -> 'BlobRequest':
request = json.loads(data)
return cls([
request_type(**request)
for request_type in (BlobPriceRequest, BlobAvailabilityRequest, BlobDownloadRequest,
BlobPaymentAddressRequest)
if request_type.key in request
])
@classmethod
def make_request_for_blob_hash(cls, blob_hash: str) -> 'BlobRequest':
return cls(
[BlobAvailabilityRequest([blob_hash]), BlobPriceRequest(0.0), BlobDownloadRequest(blob_hash)]
)
class BlobResponse:
def __init__(self, responses: typing.List[blob_response_types], blob_data: typing.Optional[bytes] = None) -> None:
self.responses = responses
self.blob_data = blob_data
def to_dict(self):
d = {}
for response in self.responses:
d.update(response.to_dict())
return d
def _get_response(self, response_type: blob_response_types):
response = tuple(filter(lambda r: type(r) == response_type, self.responses))
if response:
return response[0]
def get_error_response(self) -> typing.Optional[BlobErrorResponse]:
error = self._get_response(BlobErrorResponse)
if error:
log.error(error)
return error
def get_availability_response(self) -> typing.Optional[BlobAvailabilityResponse]:
response = self._get_response(BlobAvailabilityResponse)
if response:
return response
def get_price_response(self) -> typing.Optional[BlobPriceResponse]:
response = self._get_response(BlobPriceResponse)
if response:
return response
def get_blob_response(self) -> typing.Optional[BlobDownloadResponse]:
response = self._get_response(BlobDownloadResponse)
if response:
return response
def get_address_response(self) -> typing.Optional[BlobPaymentAddressResponse]:
response = self._get_response(BlobPaymentAddressResponse)
if response:
return response
def serialize(self) -> bytes:
return json.dumps(self.to_dict()).encode()
@classmethod
def deserialize(cls, data: bytes) -> 'BlobResponse':
response, extra = _parse_blob_response(data)
requests = []
if response:
requests.extend([
response_type(**response)
for response_type in (BlobPriceResponse, BlobAvailabilityResponse, BlobDownloadResponse,
BlobErrorResponse, BlobPaymentAddressResponse)
if response_type.key in response
])
return cls(requests, extra)