lbry-sdk/lbrynet/core/BlobManager.py
2017-09-20 13:59:26 -04:00

262 lines
11 KiB
Python

import logging
import os
import time
import sqlite3
from twisted.internet import threads, defer, reactor
from twisted.enterprise import adbapi
from lbrynet import conf
from lbrynet.blob.blob_file import BlobFile
from lbrynet.blob.creator import BlobFileCreator
from lbrynet.core.server.DHTHashAnnouncer import DHTHashSupplier
from lbrynet.core.sqlite_helpers import rerun_if_locked
log = logging.getLogger(__name__)
class DiskBlobManager(DHTHashSupplier):
def __init__(self, hash_announcer, blob_dir, db_dir):
"""
This class stores blobs on the hard disk,
blob_dir - directory where blobs are stored
db_dir - directory where sqlite database of blob information is stored
"""
DHTHashSupplier.__init__(self, hash_announcer)
self.announce_head_blobs_only = conf.settings['announce_head_blobs_only']
self.blob_dir = blob_dir
self.db_file = os.path.join(db_dir, "blobs.db")
self.db_conn = adbapi.ConnectionPool('sqlite3', self.db_file, check_same_thread=False)
self.blob_creator_type = BlobFileCreator
# TODO: consider using an LRU for blobs as there could potentially
# be thousands of blobs loaded up, many stale
self.blobs = {}
self.blob_hashes_to_delete = {} # {blob_hash: being_deleted (True/False)}
@defer.inlineCallbacks
def setup(self):
log.info("Starting disk blob manager. blob_dir: %s, db_file: %s", str(self.blob_dir),
str(self.db_file))
yield self._open_db()
def stop(self):
log.info("Stopping disk blob manager.")
self.db_conn.close()
return defer.succeed(True)
def get_blob(self, blob_hash, length=None):
"""Return a blob identified by blob_hash, which may be a new blob or a
blob that is already on the hard disk
"""
if length is not None and not isinstance(length, int):
raise Exception("invalid length type: %s (%s)", length, str(type(length)))
if blob_hash in self.blobs:
return defer.succeed(self.blobs[blob_hash])
return self._make_new_blob(blob_hash, length)
def get_blob_creator(self):
return self.blob_creator_type(self.blob_dir)
def _make_new_blob(self, blob_hash, length=None):
log.debug('Making a new blob for %s', blob_hash)
blob = BlobFile(self.blob_dir, blob_hash, length)
self.blobs[blob_hash] = blob
return defer.succeed(blob)
def _immediate_announce(self, blob_hashes):
if self.hash_announcer:
return self.hash_announcer.immediate_announce(blob_hashes)
raise Exception("Hash announcer not set")
@defer.inlineCallbacks
def blob_completed(self, blob, next_announce_time=None, should_announce=True):
if next_announce_time is None:
next_announce_time = self.get_next_announce_time()
yield self._add_completed_blob(blob.blob_hash, blob.length,
next_announce_time, should_announce)
# we announce all blobs immediately, if announce_head_blob_only is False
# otherwise, announce only if marked as should_announce
if not self.announce_head_blobs_only or should_announce:
reactor.callLater(0, self._immediate_announce, [blob.blob_hash])
def completed_blobs(self, blobhashes_to_check):
return self._completed_blobs(blobhashes_to_check)
def hashes_to_announce(self):
return self._get_blobs_to_announce()
def creator_finished(self, blob_creator, should_announce):
log.debug("blob_creator.blob_hash: %s", blob_creator.blob_hash)
if blob_creator.blob_hash is None:
raise Exception("Blob hash is None")
if blob_creator.blob_hash in self.blobs:
raise Exception("Creator finished for blob that is already marked as completed")
if blob_creator.length is None:
raise Exception("Blob has a length of 0")
new_blob = BlobFile(self.blob_dir, blob_creator.blob_hash, blob_creator.length)
self.blobs[blob_creator.blob_hash] = new_blob
next_announce_time = self.get_next_announce_time()
d = self.blob_completed(new_blob, next_announce_time, should_announce)
return d
def immediate_announce_all_blobs(self):
d = self._get_all_verified_blob_hashes()
d.addCallback(self._immediate_announce)
return d
def get_all_verified_blobs(self):
d = self._get_all_verified_blob_hashes()
d.addCallback(self.completed_blobs)
return d
def add_blob_to_download_history(self, blob_hash, host, rate):
d = self._add_blob_to_download_history(blob_hash, host, rate)
return d
def add_blob_to_upload_history(self, blob_hash, host, rate):
d = self._add_blob_to_upload_history(blob_hash, host, rate)
return d
@defer.inlineCallbacks
def delete_blobs(self, blob_hashes):
bh_to_delete_from_db = []
for blob_hash in blob_hashes:
try:
blob = yield self.get_blob(blob_hash)
yield blob.delete()
bh_to_delete_from_db.append(blob_hash)
except Exception as e:
log.warning("Failed to delete blob file. Reason: %s", e)
yield self._delete_blobs_from_db(bh_to_delete_from_db)
######### database calls #########
def _open_db(self):
# check_same_thread=False is solely to quiet a spurious error that appears to be due
# to a bug in twisted, where the connection is closed by a different thread than the
# one that opened it. The individual connections in the pool are not used in multiple
# threads.
def create_tables(transaction):
transaction.execute('PRAGMA journal_mode=WAL')
transaction.execute("create table if not exists blobs (" +
" blob_hash text primary key, " +
" blob_length integer, " +
" last_verified_time real, " +
" next_announce_time real, " +
" should_announce integer)")
transaction.execute("create table if not exists download (" +
" id integer primary key autoincrement, " +
" blob text, " +
" host text, " +
" rate float, " +
" ts integer)")
transaction.execute("create table if not exists upload (" +
" id integer primary key autoincrement, " +
" blob text, " +
" host text, " +
" rate float, " +
" ts integer)")
return self.db_conn.runInteraction(create_tables)
@rerun_if_locked
def _add_completed_blob(self, blob_hash, length, next_announce_time, should_announce):
log.debug("Adding a completed blob. blob_hash=%s, length=%s", blob_hash, str(length))
should_announce = 1 if should_announce else 0
d = self.db_conn.runQuery(
"insert into blobs (blob_hash, blob_length, next_announce_time, should_announce) "+
"values (?, ?, ?, ?)",
(blob_hash, length, next_announce_time, should_announce)
)
d.addErrback(lambda err: err.trap(sqlite3.IntegrityError))
return d
@defer.inlineCallbacks
def _completed_blobs(self, blobhashes_to_check):
"""Returns of the blobhashes_to_check, which are valid"""
blobs = yield defer.DeferredList([self.get_blob(b) for b in blobhashes_to_check])
blob_hashes = [b.blob_hash for success, b in blobs if success and b.verified]
defer.returnValue(blob_hashes)
@rerun_if_locked
def _update_blob_verified_timestamp(self, blob, timestamp):
return self.db_conn.runQuery("update blobs set last_verified_time = ? where blob_hash = ?",
(blob, timestamp))
@rerun_if_locked
def _get_blobs_to_announce(self):
def get_and_update(transaction):
timestamp = time.time()
if self.announce_head_blobs_only is True:
r = transaction.execute("select blob_hash from blobs " +
"where next_announce_time < ? and blob_hash is not null "+
"and should_announce = 1",
(timestamp,))
else:
r = transaction.execute("select blob_hash from blobs " +
"where next_announce_time < ? and blob_hash is not null",
(timestamp,))
blobs = [b for b, in r.fetchall()]
next_announce_time = self.get_next_announce_time(len(blobs))
transaction.execute(
"update blobs set next_announce_time = ? where next_announce_time < ?",
(next_announce_time, timestamp))
log.debug("Got %s blobs to announce, next announce time is in %s seconds",
len(blobs), next_announce_time-time.time())
return blobs
return self.db_conn.runInteraction(get_and_update)
@rerun_if_locked
def _delete_blobs_from_db(self, blob_hashes):
def delete_blobs(transaction):
for b in blob_hashes:
transaction.execute("delete from blobs where blob_hash = ?", (b,))
return self.db_conn.runInteraction(delete_blobs)
@rerun_if_locked
def _get_all_blob_hashes(self):
d = self.db_conn.runQuery("select blob_hash from blobs")
return d
@rerun_if_locked
def _get_all_verified_blob_hashes(self):
d = self._get_all_blob_hashes()
def get_verified_blobs(blobs):
verified_blobs = []
for blob_hash, in blobs:
file_path = os.path.join(self.blob_dir, blob_hash)
if os.path.isfile(file_path):
verified_blobs.append(blob_hash)
return verified_blobs
d.addCallback(lambda blobs: threads.deferToThread(get_verified_blobs, blobs))
return d
@rerun_if_locked
def _add_blob_to_download_history(self, blob_hash, host, rate):
ts = int(time.time())
d = self.db_conn.runQuery(
"insert into download values (null, ?, ?, ?, ?) ",
(blob_hash, str(host), float(rate), ts))
return d
@rerun_if_locked
def _add_blob_to_upload_history(self, blob_hash, host, rate):
ts = int(time.time())
d = self.db_conn.runQuery(
"insert into upload values (null, ?, ?, ?, ?) ",
(blob_hash, str(host), float(rate), ts))
return d