lbry-sdk/lbry/wallet/server/daemon.py
2020-03-01 15:17:21 -05:00

357 lines
14 KiB
Python

import asyncio
import itertools
import json
import time
from functools import wraps
from pylru import lrucache
import aiohttp
from lbry.wallet.rpc.jsonrpc import RPCError
from lbry.wallet.server.util import hex_to_bytes, class_logger
from lbry.wallet.rpc import JSONRPC
from lbry.wallet.server.prometheus import LBRYCRD_REQUEST_TIMES, LBRYCRD_PENDING_COUNT
class DaemonError(Exception):
"""Raised when the daemon returns an error in its results."""
class WarmingUpError(Exception):
"""Internal - when the daemon is warming up."""
class WorkQueueFullError(Exception):
"""Internal - when the daemon's work queue is full."""
class Daemon:
"""Handles connections to a daemon at the given URL."""
WARMING_UP = -28
id_counter = itertools.count()
def __init__(self, coin, url, max_workqueue=10, init_retry=0.25,
max_retry=4.0):
self.coin = coin
self.logger = class_logger(__name__, self.__class__.__name__)
self.set_url(url)
# Limit concurrent RPC calls to this number.
# See DEFAULT_HTTP_WORKQUEUE in bitcoind, which is typically 16
self.workqueue_semaphore = asyncio.Semaphore(value=max_workqueue)
self.init_retry = init_retry
self.max_retry = max_retry
self._height = None
self.available_rpcs = {}
self.connector = aiohttp.TCPConnector()
self._block_hash_cache = lrucache(1000000)
self._block_cache = lrucache(100000)
async def close(self):
if self.connector:
await self.connector.close()
self.connector = None
def set_url(self, url):
"""Set the URLS to the given list, and switch to the first one."""
urls = url.split(',')
urls = [self.coin.sanitize_url(url) for url in urls]
for n, url in enumerate(urls):
status = '' if n else ' (current)'
logged_url = self.logged_url(url)
self.logger.info(f'daemon #{n + 1} at {logged_url}{status}')
self.url_index = 0
self.urls = urls
def current_url(self):
"""Returns the current daemon URL."""
return self.urls[self.url_index]
def logged_url(self, url=None):
"""The host and port part, for logging."""
url = url or self.current_url()
return url[url.rindex('@') + 1:]
def failover(self):
"""Call to fail-over to the next daemon URL.
Returns False if there is only one, otherwise True.
"""
if len(self.urls) > 1:
self.url_index = (self.url_index + 1) % len(self.urls)
self.logger.info(f'failing over to {self.logged_url()}')
return True
return False
def client_session(self):
"""An aiohttp client session."""
return aiohttp.ClientSession(connector=self.connector, connector_owner=False)
async def _send_data(self, data):
if not self.connector:
raise asyncio.CancelledError('Tried to send request during shutdown.')
async with self.workqueue_semaphore:
async with self.client_session() as session:
async with session.post(self.current_url(), data=data) as resp:
kind = resp.headers.get('Content-Type', None)
if kind == 'application/json':
return await resp.json()
# bitcoind's HTTP protocol "handling" is a bad joke
text = await resp.text()
if 'Work queue depth exceeded' in text:
raise WorkQueueFullError
text = text.strip() or resp.reason
self.logger.error(text)
raise DaemonError(text)
async def _send(self, payload, processor):
"""Send a payload to be converted to JSON.
Handles temporary connection issues. Daemon response errors
are raise through DaemonError.
"""
def log_error(error):
nonlocal last_error_log, retry
now = time.time()
if now - last_error_log > 60:
last_error_log = now
self.logger.error(f'{error} Retrying occasionally...')
if retry == self.max_retry and self.failover():
retry = 0
on_good_message = None
last_error_log = 0
data = json.dumps(payload)
retry = self.init_retry
methods = tuple(
[payload['method']] if isinstance(payload, dict) else [request['method'] for request in payload]
)
while True:
try:
for method in methods:
LBRYCRD_PENDING_COUNT.labels(method=method).inc()
result = await self._send_data(data)
result = processor(result)
if on_good_message:
self.logger.info(on_good_message)
return result
except asyncio.TimeoutError:
log_error('timeout error.')
except aiohttp.ServerDisconnectedError:
log_error('disconnected.')
on_good_message = 'connection restored'
except aiohttp.ClientConnectionError:
log_error('connection problem - is your daemon running?')
on_good_message = 'connection restored'
except aiohttp.ClientError as e:
log_error(f'daemon error: {e}')
on_good_message = 'running normally'
except WarmingUpError:
log_error('starting up checking blocks.')
on_good_message = 'running normally'
except WorkQueueFullError:
log_error('work queue full.')
on_good_message = 'running normally'
finally:
for method in methods:
LBRYCRD_PENDING_COUNT.labels(method=method).dec()
await asyncio.sleep(retry)
retry = max(min(self.max_retry, retry * 2), self.init_retry)
async def _send_single(self, method, params=None):
"""Send a single request to the daemon."""
start = time.perf_counter()
def processor(result):
err = result['error']
if not err:
return result['result']
if err.get('code') == self.WARMING_UP:
raise WarmingUpError
raise DaemonError(err)
payload = {'method': method, 'id': next(self.id_counter)}
if params:
payload['params'] = params
result = await self._send(payload, processor)
LBRYCRD_REQUEST_TIMES.labels(method=method).observe(time.perf_counter() - start)
return result
async def _send_vector(self, method, params_iterable, replace_errs=False):
"""Send several requests of the same method.
The result will be an array of the same length as params_iterable.
If replace_errs is true, any item with an error is returned as None,
otherwise an exception is raised."""
start = time.perf_counter()
def processor(result):
errs = [item['error'] for item in result if item['error']]
if any(err.get('code') == self.WARMING_UP for err in errs):
raise WarmingUpError
if not errs or replace_errs:
return [item['result'] for item in result]
raise DaemonError(errs)
payload = [{'method': method, 'params': p, 'id': next(self.id_counter)}
for p in params_iterable]
result = []
if payload:
result = await self._send(payload, processor)
LBRYCRD_REQUEST_TIMES.labels(method=method).observe(time.perf_counter()-start)
return result
async def _is_rpc_available(self, method):
"""Return whether given RPC method is available in the daemon.
Results are cached and the daemon will generally not be queried with
the same method more than once."""
available = self.available_rpcs.get(method)
if available is None:
available = True
try:
await self._send_single(method)
except DaemonError as e:
err = e.args[0]
error_code = err.get("code")
available = error_code != JSONRPC.METHOD_NOT_FOUND
self.available_rpcs[method] = available
return available
async def block_hex_hashes(self, first, count):
"""Return the hex hashes of count block starting at height first."""
if first + count < (self.cached_height() or 0) - 200:
return await self._cached_block_hex_hashes(first, count)
params_iterable = ((h, ) for h in range(first, first + count))
return await self._send_vector('getblockhash', params_iterable)
async def _cached_block_hex_hashes(self, first, count):
"""Return the hex hashes of count block starting at height first."""
cached = self._block_hash_cache.get((first, count))
if cached:
return cached
params_iterable = ((h, ) for h in range(first, first + count))
self._block_hash_cache[(first, count)] = await self._send_vector('getblockhash', params_iterable)
return self._block_hash_cache[(first, count)]
async def deserialised_block(self, hex_hash):
"""Return the deserialised block with the given hex hash."""
if not self._block_cache.get(hex_hash):
self._block_cache[hex_hash] = await self._send_single('getblock', (hex_hash, True))
return self._block_cache[hex_hash]
async def raw_blocks(self, hex_hashes):
"""Return the raw binary blocks with the given hex hashes."""
params_iterable = ((h, False) for h in hex_hashes)
blocks = await self._send_vector('getblock', params_iterable)
# Convert hex string to bytes
return [hex_to_bytes(block) for block in blocks]
async def mempool_hashes(self):
"""Update our record of the daemon's mempool hashes."""
return await self._send_single('getrawmempool')
async def estimatefee(self, block_count):
"""Return the fee estimate for the block count. Units are whole
currency units per KB, e.g. 0.00000995, or -1 if no estimate
is available.
"""
args = (block_count, )
if await self._is_rpc_available('estimatesmartfee'):
estimate = await self._send_single('estimatesmartfee', args)
return estimate.get('feerate', -1)
return await self._send_single('estimatefee', args)
async def getnetworkinfo(self):
"""Return the result of the 'getnetworkinfo' RPC call."""
return await self._send_single('getnetworkinfo')
async def relayfee(self):
"""The minimum fee a low-priority tx must pay in order to be accepted
to the daemon's memory pool."""
network_info = await self.getnetworkinfo()
return network_info['relayfee']
async def getrawtransaction(self, hex_hash, verbose=False):
"""Return the serialized raw transaction with the given hash."""
# Cast to int because some coin daemons are old and require it
return await self._send_single('getrawtransaction',
(hex_hash, int(verbose)))
async def getrawtransactions(self, hex_hashes, replace_errs=True):
"""Return the serialized raw transactions with the given hashes.
Replaces errors with None by default."""
params_iterable = ((hex_hash, 0) for hex_hash in hex_hashes)
txs = await self._send_vector('getrawtransaction', params_iterable,
replace_errs=replace_errs)
# Convert hex strings to bytes
return [hex_to_bytes(tx) if tx else None for tx in txs]
async def broadcast_transaction(self, raw_tx):
"""Broadcast a transaction to the network."""
return await self._send_single('sendrawtransaction', (raw_tx, ))
async def height(self):
"""Query the daemon for its current height."""
self._height = await self._send_single('getblockcount')
return self._height
def cached_height(self):
"""Return the cached daemon height.
If the daemon has not been queried yet this returns None."""
return self._height
def handles_errors(decorated_function):
@wraps(decorated_function)
async def wrapper(*args, **kwargs):
try:
return await decorated_function(*args, **kwargs)
except DaemonError as daemon_error:
raise RPCError(1, daemon_error.args[0])
return wrapper
class LBCDaemon(Daemon):
@handles_errors
async def getrawtransaction(self, hex_hash, verbose=False):
return await super().getrawtransaction(hex_hash=hex_hash, verbose=verbose)
@handles_errors
async def getclaimbyid(self, claim_id):
'''Given a claim id, retrieves claim information.'''
return await self._send_single('getclaimbyid', (claim_id,))
@handles_errors
async def getclaimsbyids(self, claim_ids):
'''Given a list of claim ids, batches calls to retrieve claim information.'''
return await self._send_vector('getclaimbyid', ((claim_id,) for claim_id in claim_ids))
@handles_errors
async def getclaimsforname(self, name):
'''Given a name, retrieves all claims matching that name.'''
return await self._send_single('getclaimsforname', (name,))
@handles_errors
async def getclaimsfortx(self, txid):
'''Given a txid, returns the claims it make.'''
return await self._send_single('getclaimsfortx', (txid,)) or []
@handles_errors
async def getnameproof(self, name, block_hash=None):
'''Given a name and optional block_hash, returns a name proof and winner, if any.'''
return await self._send_single('getnameproof', (name, block_hash,) if block_hash else (name,))
@handles_errors
async def getvalueforname(self, name):
'''Given a name, returns the winning claim value.'''
return await self._send_single('getvalueforname', (name,))
@handles_errors
async def claimname(self, name, hexvalue, amount):
'''Claim a name, used for functional tests only.'''
return await self._send_single('claimname', (name, hexvalue, float(amount)))