Merge pull request #931 from lbryio/fix_blob_reader_closing

Fixes to Blob (unify way to read from BlobFile, move conf.py BLOB_SIZE  )

CHANGELOG.md

@@ -22,7 +22,7 @@ at anytime.
   *
 
 ### Changed
-  *
+  * Moved BLOB_SIZE from conf.py to MAX_BLOB_SIZE in blob/blob_file.py
   *
 
 ### Added
@@ -30,7 +30,7 @@ at anytime.
   *
 
 ### Removed
-  *
+  * Removed some alternate methods of reading from blob files
   *
 
 

lbrynet/blob/blob_file.py

@@ -1,18 +1,16 @@
 import logging
 import os
 from twisted.internet import defer, threads
-from twisted.protocols.basic import FileSender
 from twisted.web.client import FileBodyProducer
 from twisted.python.failure import Failure
-from lbrynet import conf
 from lbrynet.core.Error import DownloadCanceledError, InvalidDataError, InvalidBlobHashError
 from lbrynet.core.utils import is_valid_blobhash
 from lbrynet.blob.writer import HashBlobWriter
-from lbrynet.blob.reader import HashBlobReader, HashBlobReader_v0
-
+from lbrynet.blob.reader import HashBlobReader
 
 log = logging.getLogger(__name__)
 
+MAX_BLOB_SIZE = 2 * 2 ** 20
 
 class BlobFile(object):
     """
@@ -78,7 +76,8 @@ class BlobFile(object):
         finished
         """
         if self._verified is True:
-            reader = HashBlobReader(self.file_path, self.reader_finished)
+            f = open(self.file_path, 'rb')
+            reader = HashBlobReader(f, self.reader_finished)
             self.readers += 1
             return reader
         return None
@@ -124,7 +123,7 @@ class BlobFile(object):
     def set_length(self, length):
         if self.length is not None and length == self.length:
             return True
-        if self.length is None and 0 <= length <= conf.settings['BLOB_SIZE']:
+        if self.length is None and 0 <= length <= MAX_BLOB_SIZE:
             self.length = length
             return True
         log.warning("Got an invalid length. Previous length: %s, Invalid length: %s",
@@ -142,33 +141,6 @@ class BlobFile(object):
             return True
         return False
 
-    def read(self, write_func):
-        """
-        This function is only used in StreamBlobDecryptor
-        and should be deprecated in favor of open_for_reading()
-        """
-        def close_self(*args):
-            self.close_read_handle(file_handle)
-            return args[0]
-
-        file_sender = FileSender()
-        reader = HashBlobReader_v0(write_func)
-        file_handle = self.open_for_reading()
-        if file_handle is not None:
-            d = file_sender.beginFileTransfer(file_handle, reader)
-            d.addCallback(close_self)
-        else:
-            d = defer.fail(IOError("Could not read the blob"))
-        return d
-
-    def close_read_handle(self, file_handle):
-        """
-        This function is only used in StreamBlobDecryptor
-        and should be deprecated in favor of open_for_reading()
-        """
-        if file_handle is not None:
-            file_handle.close()
-
     def reader_finished(self, reader):
         self.readers -= 1
         return defer.succeed(True)

lbrynet/blob/reader.py

@@ -1,50 +1,22 @@
 import logging
-from twisted.internet import interfaces
-from zope.interface import implements
 
 log = logging.getLogger(__name__)
 
 
-class HashBlobReader_v0(object):
-    """
-    This is a class that is only used in StreamBlobDecryptor
-    and should be deprecated
-    """
-    implements(interfaces.IConsumer)
-
-    def __init__(self, write_func):
-        self.write_func = write_func
-
-    def registerProducer(self, producer, streaming):
-        from twisted.internet import reactor
-
-        self.producer = producer
-        self.streaming = streaming
-        if self.streaming is False:
-            reactor.callLater(0, self.producer.resumeProducing)
-
-    def unregisterProducer(self):
-        pass
-
-    def write(self, data):
-        from twisted.internet import reactor
-
-        self.write_func(data)
-        if self.streaming is False:
-            reactor.callLater(0, self.producer.resumeProducing)
-
-
 class HashBlobReader(object):
     """
     This is a file like reader class that supports
     read(size) and close()
     """
-    def __init__(self, file_path, finished_cb):
+    def __init__(self, read_handle, finished_cb):
         self.finished_cb = finished_cb
         self.finished_cb_d = None
-        self.read_handle = open(file_path, 'rb')
+        self.read_handle = read_handle
 
     def __del__(self):
+        if self.finished_cb_d is None:
+            log.warn("Garbage collection was called, but reader for %s was not closed yet",
+                        self.read_handle.name)
         self.close()
 
     def read(self, size=-1):

lbrynet/blob/writer.py

@@ -16,6 +16,11 @@ class HashBlobWriter(object):
         self._hashsum = get_lbry_hash_obj()
         self.len_so_far = 0
 
+    def __del__(self):
+        if self.finished_cb_d is None:
+            log.warn("Garbage collection was called, but writer was not closed yet")
+        self.close()
+
     @property
     def blob_hash(self):
         return self._hashsum.hexdigest()

lbrynet/conf.py

@@ -206,7 +206,6 @@ FIXED_SETTINGS = {
     'API_ADDRESS': 'lbryapi',
     'APP_NAME': APP_NAME,
     'BLOBFILES_DIR': 'blobfiles',
-    'BLOB_SIZE': 2 * MB,
     'CRYPTSD_FILE_EXTENSION': '.cryptsd',
     'CURRENCIES': {
         'BTC': {'type': 'crypto'},

lbrynet/core/client/ClientRequest.py

@@ -1,5 +1,4 @@
-from lbrynet import conf
-
+from lbrynet.blob.blob_file import MAX_BLOB_SIZE
 
 class ClientRequest(object):
     def __init__(self, request_dict, response_identifier=None):
@@ -17,7 +16,7 @@ class ClientBlobRequest(ClientPaidRequest):
     def __init__(self, request_dict, response_identifier, write_func, finished_deferred,
                  cancel_func, blob):
         if blob.length is None:
-            max_pay_units = conf.settings['BLOB_SIZE']
+            max_pay_units = MAX_BLOB_SIZE
         else:
             max_pay_units = blob.length
         ClientPaidRequest.__init__(self, request_dict, response_identifier, max_pay_units)

lbrynet/cryptstream/CryptBlob.py

@@ -1,13 +1,14 @@
 import binascii
 import logging
+from io import BytesIO
 from twisted.internet import defer
+from twisted.web.client import FileBodyProducer
 from cryptography.hazmat.primitives.ciphers import Cipher, modes
 from cryptography.hazmat.primitives.ciphers.algorithms import AES
 from cryptography.hazmat.primitives.padding import PKCS7
 from cryptography.hazmat.backends import default_backend
-from lbrynet import conf
 from lbrynet.core.BlobInfo import BlobInfo
-
+from lbrynet.blob.blob_file import MAX_BLOB_SIZE
 
 log = logging.getLogger(__name__)
 backend = default_backend()
@@ -46,6 +47,10 @@ class StreamBlobDecryptor(object):
 
         write_func - function that takes decrypted string as
             arugment and writes it somewhere
+
+        Returns:
+
+        deferred that returns after decrypting blob and writing content
         """
 
         def remove_padding(data):
@@ -67,13 +72,20 @@ class StreamBlobDecryptor(object):
             last_chunk = self.cipher.update(data_to_decrypt) + self.cipher.finalize()
             write_func(remove_padding(last_chunk))
 
-        def decrypt_bytes(data):
-            self.buff += data
-            self.len_read += len(data)
-            write_bytes()
 
-        d = self.blob.read(decrypt_bytes)
-        d.addCallback(lambda _: finish_decrypt())
+        read_handle = self.blob.open_for_reading()
+
+        @defer.inlineCallbacks
+        def decrypt_bytes():
+            producer = FileBodyProducer(read_handle)
+            buff = BytesIO()
+            yield producer.startProducing(buff)
+            self.buff = buff.getvalue()
+            self.len_read += len(self.buff)
+            write_bytes()
+            finish_decrypt()
+
+        d = decrypt_bytes()
         return d
 
 
@@ -106,7 +118,7 @@ class CryptStreamBlobMaker(object):
         max bytes are written. num_bytes_to_write is the number
         of bytes that will be written from data in this call
         """
-        max_bytes_to_write = conf.settings['BLOB_SIZE'] - self.length - 1
+        max_bytes_to_write = MAX_BLOB_SIZE - self.length - 1
         done = False
         if max_bytes_to_write <= len(data):
             num_bytes_to_write = max_bytes_to_write

lbrynet/tests/unit/cryptstream/test_cryptblob.py

@@ -1,7 +1,7 @@
 from twisted.trial import unittest
 from twisted.internet import defer
 from lbrynet.cryptstream import CryptBlob
-from lbrynet import conf
+from lbrynet.blob.blob_file import MAX_BLOB_SIZE
 
 from lbrynet.tests.mocks import mock_conf_settings
 
@@ -9,6 +9,7 @@ from Crypto import Random
 from Crypto.Cipher import AES
 import random
 import string
+import StringIO
 
 class MocBlob(object):
     def __init__(self):
@@ -19,6 +20,9 @@ class MocBlob(object):
         write_func(data)
         return defer.succeed(True)
 
+    def open_for_reading(self):
+        return StringIO.StringIO(self.data)
+
     def write(self, data):
         self.data += data
 
@@ -53,7 +57,7 @@ class TestCryptBlob(unittest.TestCase):
         expected_encrypted_blob_size = ((size_of_data / AES.block_size) + 1) * AES.block_size
         self.assertEqual(expected_encrypted_blob_size, len(blob.data))
 
-        if size_of_data < conf.settings['BLOB_SIZE']-1:
+        if size_of_data < MAX_BLOB_SIZE-1:
             self.assertFalse(done)
         else:
             self.assertTrue(done)
@@ -64,7 +68,7 @@ class TestCryptBlob(unittest.TestCase):
 
         # decrypt string
         decryptor = CryptBlob.StreamBlobDecryptor(blob, key, iv, size_of_data)
-        decryptor.decrypt(write_func)
+        yield decryptor.decrypt(write_func)
         self.assertEqual(self.data_buf, string_to_encrypt)
 
     @defer.inlineCallbacks