--- /dev/null
+
+"""An sqlite database for storing persistent files and hashes."""
+
+from datetime import datetime, timedelta
+from pysqlite2 import dbapi2 as sqlite
+from binascii import a2b_base64, b2a_base64
+from time import sleep
+import os
+
+from twisted.python.filepath import FilePath
+from twisted.trial import unittest
+
+assert sqlite.version_info >= (2, 1)
+
+class DBExcept(Exception):
+ """An error occurred in accessing the database."""
+ pass
+
+class khash(str):
+ """Dummy class to convert all hashes to base64 for storing in the DB."""
+
+# Initialize the database to work with 'khash' objects (binary strings)
+sqlite.register_adapter(khash, b2a_base64)
+sqlite.register_converter("KHASH", a2b_base64)
+sqlite.register_converter("khash", a2b_base64)
+sqlite.enable_callback_tracebacks(True)
+
+class DB:
+ """An sqlite database for storing persistent files and hashes.
+
+ @type db: L{twisted.python.filepath.FilePath}
+ @ivar db: the database file to use
+ @type conn: L{pysqlite2.dbapi2.Connection}
+ @ivar conn: an open connection to the sqlite database
+ """
+
+ def __init__(self, db):
+ """Load or create the database file.
+
+ @type db: L{twisted.python.filepath.FilePath}
+ @param db: the database file to use
+ """
+ self.db = db
+ self.db.restat(False)
+ if self.db.exists():
+ self._loadDB()
+ else:
+ self._createNewDB()
+ self.conn.text_factory = str
+ self.conn.row_factory = sqlite.Row
+
+ def _loadDB(self):
+ """Open a new connection to the existing database file"""
+ try:
+ self.conn = sqlite.connect(database=self.db.path, detect_types=sqlite.PARSE_DECLTYPES)
+ except:
+ import traceback
+ raise DBExcept, "Couldn't open DB", traceback.format_exc()
+
+ def _createNewDB(self):
+ """Open a connection to a new database and create the necessary tables."""
+ if not self.db.parent().exists():
+ self.db.parent().makedirs()
+ self.conn = sqlite.connect(database=self.db.path, detect_types=sqlite.PARSE_DECLTYPES)
+ c = self.conn.cursor()
+ c.execute("CREATE TABLE files (path TEXT PRIMARY KEY UNIQUE, hashID INTEGER, " +
+ "size NUMBER, mtime NUMBER)")
+ c.execute("CREATE TABLE hashes (hashID INTEGER PRIMARY KEY AUTOINCREMENT, " +
+ "hash KHASH UNIQUE, pieces KHASH, " +
+ "piecehash KHASH, refreshed TIMESTAMP)")
+ c.execute("CREATE INDEX hashes_refreshed ON hashes(refreshed)")
+ c.execute("CREATE INDEX hashes_piecehash ON hashes(piecehash)")
+ c.close()
+ self.conn.commit()
+
+ def _removeChanged(self, file, row):
+ """If the file has changed or is missing, remove it from the DB.
+
+ @type file: L{twisted.python.filepath.FilePath}
+ @param file: the file to check
+ @type row: C{dictionary}-like object
+ @param row: contains the expected 'size' and 'mtime' of the file
+ @rtype: C{boolean}
+ @return: True if the file is unchanged, False if it is changed,
+ and None if it is missing
+ """
+ res = None
+ if row:
+ file.restat(False)
+ if file.exists():
+ # Compare the current with the expected file properties
+ res = (row['size'] == file.getsize() and row['mtime'] == file.getmtime())
+ if not res:
+ # Remove the file from the database
+ c = self.conn.cursor()
+ c.execute("DELETE FROM files WHERE path = ?", (file.path, ))
+ self.conn.commit()
+ c.close()
+ return res
+
+ def storeFile(self, file, hash, pieces = ''):
+ """Store or update a file in the database.
+
+ @type file: L{twisted.python.filepath.FilePath}
+ @param file: the file to check
+ @type hash: C{string}
+ @param hash: the hash of the file
+ @type pieces: C{string}
+ @param pieces: the concatenated list of the hashes of the pieces of
+ the file (optional, defaults to the empty string)
+ @return: True if the hash was not in the database before
+ (so it needs to be added to the DHT)
+ """
+ # Hash the pieces to get the piecehash
+ piecehash = ''
+ if pieces:
+ s = sha.new().update(pieces)
+ piecehash = sha.digest()
+
+ # Check the database for the hash
+ c = self.conn.cursor()
+ c.execute("SELECT hashID, piecehash FROM hashes WHERE hash = ?", (khash(hash), ))
+ row = c.fetchone()
+ if row:
+ assert piecehash == row['piecehash']
+ new_hash = False
+ hashID = row['hashID']
+ else:
+ # Add the new hash to the database
+ c = self.conn.cursor()
+ c.execute("INSERT OR REPLACE INTO hashes (hash, pieces, piecehash, refreshed) VALUES (?, ?, ?, ?)",
+ (khash(hash), khash(pieces), khash(piecehash), datetime.now()))
+ self.conn.commit()
+ new_hash = True
+ hashID = c.lastrowid
+
+ # Add the file to the database
+ file.restat()
+ c.execute("INSERT OR REPLACE INTO files (path, hashID, size, mtime) VALUES (?, ?, ?, ?)",
+ (file.path, hashID, file.getsize(), file.getmtime()))
+ self.conn.commit()
+ c.close()
+
+ return new_hash
+
+ def getFile(self, file):
+ """Get a file from the database.
+
+ If it has changed or is missing, it is removed from the database.
+
+ @type file: L{twisted.python.filepath.FilePath}
+ @param file: the file to check
+ @return: dictionary of info for the file, False if changed, or
+ None if not in database or missing
+ """
+ c = self.conn.cursor()
+ c.execute("SELECT hash, size, mtime, pieces FROM files JOIN hashes USING (hashID) WHERE path = ?", (file.path, ))
+ row = c.fetchone()
+ res = None
+ if row:
+ res = self._removeChanged(file, row)
+ if res:
+ res = {}
+ res['hash'] = row['hash']
+ res['size'] = row['size']
+ res['pieces'] = row['pieces']
+ c.close()
+ return res
+
+ def lookupHash(self, hash, filesOnly = False):
+ """Find a file by hash in the database.
+
+ If any found files have changed or are missing, they are removed
+ from the database. If filesOnly is False then it will also look for
+ piece string hashes if no files can be found.
+
+ @return: list of dictionaries of info for the found files
+ """
+ # Try to find the hash in the files table
+ c = self.conn.cursor()
+ c.execute("SELECT path, size, mtime, refreshed, pieces FROM files JOIN hashes USING (hashID) WHERE hash = ?", (khash(hash), ))
+ row = c.fetchone()
+ files = []
+ while row:
+ # Save the file to the list of found files
+ file = FilePath(row['path'])
+ res = self._removeChanged(file, row)
+ if res:
+ res = {}
+ res['path'] = file
+ res['size'] = row['size']
+ res['refreshed'] = row['refreshed']
+ res['pieces'] = row['pieces']
+ files.append(res)
+ row = c.fetchone()
+
+ if not filesOnly and not files:
+ # No files were found, so check the piecehashes as well
+ c.execute("SELECT refreshed, pieces, piecehash FROM hashes WHERE piecehash = ?", (khash(hash), ))
+ row = c.fetchone()
+ if row:
+ res = {}
+ res['refreshed'] = row['refreshed']
+ res['pieces'] = row['pieces']
+ files.append(res)
+
+ c.close()
+ return files
+
+ def isUnchanged(self, file):
+ """Check if a file in the file system has changed.
+
+ If it has changed, it is removed from the database.
+
+ @return: True if unchanged, False if changed, None if not in database
+ """
+ c = self.conn.cursor()
+ c.execute("SELECT size, mtime FROM files WHERE path = ?", (file.path, ))
+ row = c.fetchone()
+ return self._removeChanged(file, row)
+
+ def refreshHash(self, hash):
+ """Refresh the publishing time of a hash."""
+ c = self.conn.cursor()
+ c.execute("UPDATE hashes SET refreshed = ? WHERE hash = ?", (datetime.now(), khash(hash)))
+ c.close()
+
+ def expiredHashes(self, expireAfter):
+ """Find files that need refreshing after expireAfter seconds.
+
+ For each hash that needs refreshing, finds all the files with that hash.
+ If the file has changed or is missing, it is removed from the table.
+
+ @return: dictionary with keys the hashes, values a list of FilePaths
+ """
+ t = datetime.now() - timedelta(seconds=expireAfter)
+
+ # Find all the hashes that need refreshing
+ c = self.conn.cursor()
+ c.execute("SELECT hashID, hash, pieces FROM hashes WHERE refreshed < ?", (t, ))
+ row = c.fetchone()
+ expired = {}
+ while row:
+ res = expired.setdefault(row['hash'], {})
+ res['hashID'] = row['hashID']
+ res['hash'] = row['hash']
+ res['pieces'] = row['pieces']
+ row = c.fetchone()
+
+ # Make sure there are still valid files for each hash
+ for hash in expired.values():
+ valid = False
+ c.execute("SELECT path, size, mtime FROM files WHERE hashID = ?", (hash['hashID'], ))
+ row = c.fetchone()
+ while row:
+ res = self._removeChanged(FilePath(row['path']), row)
+ if res:
+ valid = True
+ row = c.fetchone()
+ if not valid:
+ # Remove hashes for which no files are still available
+ del expired[hash['hash']]
+ c.execute("DELETE FROM hashes WHERE hashID = ?", (hash['hashID'], ))
+
+ self.conn.commit()
+ c.close()
+
+ return expired
+
+ def removeUntrackedFiles(self, dirs):
+ """Remove files that are no longer tracked by the program.
+
+ @type dirs: C{list} of L{twisted.python.filepath.FilePath}
+ @param dirs: a list of the directories that we are tracking
+ @return: list of files that were removed
+ """
+ assert len(dirs) >= 1
+
+ # Create a list of globs and an SQL statement for the directories
+ newdirs = []
+ sql = "WHERE"
+ for dir in dirs:
+ newdirs.append(dir.child('*').path)
+ sql += " path NOT GLOB ? AND"
+ sql = sql[:-4]
+
+ # Get a listing of all the files that will be removed
+ c = self.conn.cursor()
+ c.execute("SELECT path FROM files " + sql, newdirs)
+ row = c.fetchone()
+ removed = []
+ while row:
+ removed.append(FilePath(row['path']))
+ row = c.fetchone()
+
+ # Delete all the removed files from the database
+ if removed:
+ c.execute("DELETE FROM files " + sql, newdirs)
+ self.conn.commit()
+
+ return removed
+
+ def close(self):
+ """Close the database connection."""
+ self.conn.close()
+
+class TestDB(unittest.TestCase):
+ """Tests for the khashmir database."""
+
+ timeout = 5
+ db = FilePath('/tmp/khashmir.db')
+ hash = '\xca\xec\xb8\x0c\x00\xe7\x07\xf8~])\x8f\x9d\xe5_B\xff\x1a\xc4!'
+ directory = FilePath('/tmp/apt-p2p/')
+ file = FilePath('/tmp/apt-p2p/khashmir.test')
+ testfile = 'tmp/khashmir.test'
+ dirs = [FilePath('/tmp/apt-p2p/top1'),
+ FilePath('/tmp/apt-p2p/top2/sub1'),
+ FilePath('/tmp/apt-p2p/top2/sub2/')]
+
+ def setUp(self):
+ if not self.file.parent().exists():
+ self.file.parent().makedirs()
+ self.file.setContent('fgfhds')
+ self.file.touch()
+ self.store = DB(self.db)
+ self.store.storeFile(self.file, self.hash)
+
+ def test_openExistingDB(self):
+ """Tests opening an existing database."""
+ self.store.close()
+ self.store = None
+ sleep(1)
+ self.store = DB(self.db)
+ res = self.store.isUnchanged(self.file)
+ self.failUnless(res)
+
+ def test_getFile(self):
+ """Tests retrieving a file from the database."""
+ res = self.store.getFile(self.file)
+ self.failUnless(res)
+ self.failUnlessEqual(res['hash'], self.hash)
+
+ def test_lookupHash(self):
+ """Tests looking up a hash in the database."""
+ res = self.store.lookupHash(self.hash)
+ self.failUnless(res)
+ self.failUnlessEqual(len(res), 1)
+ self.failUnlessEqual(res[0]['path'].path, self.file.path)
+
+ def test_isUnchanged(self):
+ """Tests checking if a file in the database is unchanged."""
+ res = self.store.isUnchanged(self.file)
+ self.failUnless(res)
+ sleep(2)
+ self.file.touch()
+ res = self.store.isUnchanged(self.file)
+ self.failUnless(res == False)
+ res = self.store.isUnchanged(self.file)
+ self.failUnless(res is None)
+
+ def test_expiry(self):
+ """Tests retrieving the files from the database that have expired."""
+ res = self.store.expiredHashes(1)
+ self.failUnlessEqual(len(res.keys()), 0)
+ sleep(2)
+ res = self.store.expiredHashes(1)
+ self.failUnlessEqual(len(res.keys()), 1)
+ self.failUnlessEqual(res.keys()[0], self.hash)
+ self.store.refreshHash(self.hash)
+ res = self.store.expiredHashes(1)
+ self.failUnlessEqual(len(res.keys()), 0)
+
+ def build_dirs(self):
+ for dir in self.dirs:
+ file = dir.preauthChild(self.testfile)
+ if not file.parent().exists():
+ file.parent().makedirs()
+ file.setContent(file.path)
+ file.touch()
+ self.store.storeFile(file, self.hash)
+
+ def test_multipleHashes(self):
+ """Tests looking up a hash with multiple files in the database."""
+ self.build_dirs()
+ res = self.store.expiredHashes(1)
+ self.failUnlessEqual(len(res.keys()), 0)
+ res = self.store.lookupHash(self.hash)
+ self.failUnless(res)
+ self.failUnlessEqual(len(res), 4)
+ self.failUnlessEqual(res[0]['refreshed'], res[1]['refreshed'])
+ self.failUnlessEqual(res[0]['refreshed'], res[2]['refreshed'])
+ self.failUnlessEqual(res[0]['refreshed'], res[3]['refreshed'])
+ sleep(2)
+ res = self.store.expiredHashes(1)
+ self.failUnlessEqual(len(res.keys()), 1)
+ self.failUnlessEqual(res.keys()[0], self.hash)
+ self.store.refreshHash(self.hash)
+ res = self.store.expiredHashes(1)
+ self.failUnlessEqual(len(res.keys()), 0)
+
+ def test_removeUntracked(self):
+ """Tests removing untracked files from the database."""
+ self.build_dirs()
+ res = self.store.removeUntrackedFiles(self.dirs)
+ self.failUnlessEqual(len(res), 1, 'Got removed paths: %r' % res)
+ self.failUnlessEqual(res[0], self.file, 'Got removed paths: %r' % res)
+ res = self.store.removeUntrackedFiles(self.dirs)
+ self.failUnlessEqual(len(res), 0, 'Got removed paths: %r' % res)
+ res = self.store.removeUntrackedFiles(self.dirs[1:])
+ self.failUnlessEqual(len(res), 1, 'Got removed paths: %r' % res)
+ self.failUnlessEqual(res[0], self.dirs[0].preauthChild(self.testfile), 'Got removed paths: %r' % res)
+ res = self.store.removeUntrackedFiles(self.dirs[:1])
+ self.failUnlessEqual(len(res), 2, 'Got removed paths: %r' % res)
+ self.failUnlessIn(self.dirs[1].preauthChild(self.testfile), res, 'Got removed paths: %r' % res)
+ self.failUnlessIn(self.dirs[2].preauthChild(self.testfile), res, 'Got removed paths: %r' % res)
+
+ def tearDown(self):
+ self.directory.remove()
+ self.store.close()
+ self.db.remove()
+
projects / quix0rs-apt-p2p.git / blobdiff