2 """An sqlite database for storing persistent files and hashes."""
4 from datetime import datetime, timedelta
5 from pysqlite2 import dbapi2 as sqlite
6 from binascii import a2b_base64, b2a_base64
10 from twisted.python.filepath import FilePath
11 from twisted.trial import unittest
13 assert sqlite.version_info >= (2, 1)
15 class DBExcept(Exception):
16 """An error occurred in accessing the database."""
20 """Dummy class to convert all hashes to base64 for storing in the DB."""
22 # Initialize the database to work with 'khash' objects (binary strings)
23 sqlite.register_adapter(khash, b2a_base64)
24 sqlite.register_converter("KHASH", a2b_base64)
25 sqlite.register_converter("khash", a2b_base64)
26 sqlite.enable_callback_tracebacks(True)
29 """An sqlite database for storing persistent files and hashes.
31 @type db: L{twisted.python.filepath.FilePath}
32 @ivar db: the database file to use
33 @type conn: L{pysqlite2.dbapi2.Connection}
34 @ivar conn: an open connection to the sqlite database
37 def __init__(self, db):
38 """Load or create the database file.
40 @type db: L{twisted.python.filepath.FilePath}
41 @param db: the database file to use
49 self.conn.text_factory = str
50 self.conn.row_factory = sqlite.Row
54 """Open a new connection to the existing database file"""
56 self.conn = sqlite.connect(database=self.db.path, detect_types=sqlite.PARSE_DECLTYPES)
59 raise DBExcept, "Couldn't open DB", traceback.format_exc()
61 def _createNewDB(self):
62 """Open a connection to a new database and create the necessary tables."""
63 if not self.db.parent().exists():
64 self.db.parent().makedirs()
65 self.conn = sqlite.connect(database=self.db.path, detect_types=sqlite.PARSE_DECLTYPES)
66 c = self.conn.cursor()
67 c.execute("CREATE TABLE files (path TEXT PRIMARY KEY UNIQUE, hashID INTEGER, " +
68 "dht BOOL, size NUMBER, mtime NUMBER)")
69 c.execute("CREATE TABLE hashes (hashID INTEGER PRIMARY KEY AUTOINCREMENT, " +
70 "hash KHASH UNIQUE, pieces KHASH, " +
71 "piecehash KHASH, refreshed TIMESTAMP)")
72 c.execute("CREATE TABLE stats (param TEXT PRIMARY KEY UNIQUE, value NUMERIC)")
73 c.execute("CREATE INDEX hashes_hash ON hashes(hash)")
74 c.execute("CREATE INDEX hashes_refreshed ON hashes(refreshed)")
75 c.execute("CREATE INDEX hashes_piecehash ON hashes(piecehash)")
80 """Close the database connection."""
84 def _removeChanged(self, file, row):
85 """If the file has changed or is missing, remove it from the DB.
87 @type file: L{twisted.python.filepath.FilePath}
88 @param file: the file to check
89 @type row: C{dictionary}-like object
90 @param row: contains the expected 'size' and 'mtime' of the file
92 @return: True if the file is unchanged, False if it is changed,
93 and None if it is missing
99 # Compare the current with the expected file properties
100 res = (row['size'] == file.getsize() and row['mtime'] == file.getmtime())
102 # Remove the file from the database
103 c = self.conn.cursor()
104 c.execute("DELETE FROM files WHERE path = ?", (file.path, ))
109 def storeFile(self, file, hash, dht = True, pieces = ''):
110 """Store or update a file in the database.
112 @type file: L{twisted.python.filepath.FilePath}
113 @param file: the file to check
114 @type hash: C{string}
115 @param hash: the hash of the file
116 @param dht: whether the file is added to the DHT
117 (optional, defaults to true)
118 @type pieces: C{string}
119 @param pieces: the concatenated list of the hashes of the pieces of
120 the file (optional, defaults to the empty string)
121 @return: True if the hash was not in the database before
122 (so it needs to be added to the DHT)
124 # Hash the pieces to get the piecehash
127 piecehash = sha.new(pieces).digest()
129 # Check the database for the hash
130 c = self.conn.cursor()
131 c.execute("SELECT hashID, piecehash FROM hashes WHERE hash = ?", (khash(hash), ))
134 assert piecehash == row['piecehash']
136 hashID = row['hashID']
138 # Add the new hash to the database
139 c = self.conn.cursor()
140 c.execute("INSERT OR REPLACE INTO hashes (hash, pieces, piecehash, refreshed) VALUES (?, ?, ?, ?)",
141 (khash(hash), khash(pieces), khash(piecehash), datetime.now()))
146 # Add the file to the database
148 c.execute("INSERT OR REPLACE INTO files (path, hashID, dht, size, mtime) VALUES (?, ?, ?, ?, ?)",
149 (file.path, hashID, dht, file.getsize(), file.getmtime()))
155 def getFile(self, file):
156 """Get a file from the database.
158 If it has changed or is missing, it is removed from the database.
160 @type file: L{twisted.python.filepath.FilePath}
161 @param file: the file to check
162 @return: dictionary of info for the file, False if changed, or
163 None if not in database or missing
165 c = self.conn.cursor()
166 c.execute("SELECT hash, size, mtime, pieces FROM files JOIN hashes USING (hashID) WHERE path = ?", (file.path, ))
170 res = self._removeChanged(file, row)
173 res['hash'] = row['hash']
174 res['size'] = row['size']
175 res['pieces'] = row['pieces']
179 def lookupHash(self, hash, filesOnly = False):
180 """Find a file by hash in the database.
182 If any found files have changed or are missing, they are removed
183 from the database. If filesOnly is False then it will also look for
184 piece string hashes if no files can be found.
186 @return: list of dictionaries of info for the found files
188 # Try to find the hash in the files table
189 c = self.conn.cursor()
190 c.execute("SELECT path, size, mtime, refreshed, pieces FROM files JOIN hashes USING (hashID) WHERE hash = ?", (khash(hash), ))
194 # Save the file to the list of found files
195 file = FilePath(row['path'])
196 res = self._removeChanged(file, row)
200 res['size'] = row['size']
201 res['refreshed'] = row['refreshed']
202 res['pieces'] = row['pieces']
206 if not filesOnly and not files:
207 # No files were found, so check the piecehashes as well
208 c.execute("SELECT refreshed, pieces, piecehash FROM hashes WHERE piecehash = ?", (khash(hash), ))
212 res['refreshed'] = row['refreshed']
213 res['pieces'] = row['pieces']
219 def isUnchanged(self, file):
220 """Check if a file in the file system has changed.
222 If it has changed, it is removed from the database.
224 @return: True if unchanged, False if changed, None if not in database
226 c = self.conn.cursor()
227 c.execute("SELECT size, mtime FROM files WHERE path = ?", (file.path, ))
229 return self._removeChanged(file, row)
231 def refreshHash(self, hash):
232 """Refresh the publishing time of a hash."""
233 c = self.conn.cursor()
234 c.execute("UPDATE hashes SET refreshed = ? WHERE hash = ?", (datetime.now(), khash(hash)))
237 def expiredHashes(self, expireAfter):
238 """Find files that need refreshing after expireAfter seconds.
240 For each hash that needs refreshing, finds all the files with that hash.
241 If the file has changed or is missing, it is removed from the table.
243 @return: dictionary with keys the hashes, values a list of FilePaths
245 t = datetime.now() - timedelta(seconds=expireAfter)
247 # Find all the hashes that need refreshing
248 c = self.conn.cursor()
249 c.execute("SELECT hashID, hash, pieces FROM hashes WHERE refreshed < ?", (t, ))
253 res = expired.setdefault(row['hash'], {})
254 res['hashID'] = row['hashID']
255 res['hash'] = row['hash']
256 res['pieces'] = row['pieces']
259 # Make sure there are still valid DHT files for each hash
260 for hash in expired.values():
263 c.execute("SELECT path, dht, size, mtime FROM files WHERE hashID = ?", (hash['hashID'], ))
272 # Remove hashes for which no DHT files are still available
273 del expired[hash['hash']]
275 # Remove hashes for which no files are still available
276 c.execute("DELETE FROM hashes WHERE hashID = ?", (hash['hashID'], ))
278 # There are still some non-DHT files available, so refresh them
279 c.execute("UPDATE hashes SET refreshed = ? WHERE hashID = ?",
280 (datetime.now(), hash['hashID']))
287 def removeUntrackedFiles(self, dirs):
288 """Remove files that are no longer tracked by the program.
290 @type dirs: C{list} of L{twisted.python.filepath.FilePath}
291 @param dirs: a list of the directories that we are tracking
292 @return: list of files that were removed
294 assert len(dirs) >= 1
296 # Create a list of globs and an SQL statement for the directories
300 newdirs.append(dir.child('*').path)
301 sql += " path NOT GLOB ? AND"
304 # Get a listing of all the files that will be removed
305 c = self.conn.cursor()
306 c.execute("SELECT path FROM files " + sql, newdirs)
310 removed.append(FilePath(row['path']))
313 # Delete all the removed files from the database
315 c.execute("DELETE FROM files " + sql, newdirs)
318 c.execute("SELECT path FROM files")
321 if not os.path.exists(row['path']):
322 # Leave hashes, they will be removed on next refresh
323 c.execute("DELETE FROM files WHERE path = ?", (row['path'], ))
324 removed.append(FilePath(row['path']))
331 """Count the total number of files and hashes in the database.
333 @rtype: (C{int}, C{int})
334 @return: the number of distinct hashes and total files in the database
336 c = self.conn.cursor()
337 c.execute("SELECT COUNT(hash) as num_hashes FROM hashes")
342 c.execute("SELECT COUNT(path) as num_files FROM files")
350 """Retrieve the saved statistics from the DB.
352 @return: dictionary of statistics
354 c = self.conn.cursor()
355 c.execute("SELECT param, value FROM stats")
359 stats[row['param']] = row['value']
364 def saveStats(self, stats):
365 """Save the statistics to the DB."""
366 c = self.conn.cursor()
368 c.execute("INSERT OR REPLACE INTO stats (param, value) VALUES (?, ?)",
369 (param, stats[param]))
373 class TestDB(unittest.TestCase):
374 """Tests for the khashmir database."""
377 db = FilePath('/tmp/khashmir.db')
378 hash = '\xca\xec\xb8\x0c\x00\xe7\x07\xf8~])\x8f\x9d\xe5_B\xff\x1a\xc4!'
379 directory = FilePath('/tmp/apt-p2p/')
380 file = FilePath('/tmp/apt-p2p/khashmir.test')
381 testfile = 'tmp/khashmir.test'
382 dirs = [FilePath('/tmp/apt-p2p/top1'),
383 FilePath('/tmp/apt-p2p/top2/sub1'),
384 FilePath('/tmp/apt-p2p/top2/sub2/')]
387 if not self.file.parent().exists():
388 self.file.parent().makedirs()
389 self.file.setContent('fgfhds')
391 self.store = DB(self.db)
392 self.store.storeFile(self.file, self.hash)
394 def test_openExistingDB(self):
395 """Tests opening an existing database."""
399 self.store = DB(self.db)
400 res = self.store.isUnchanged(self.file)
403 def test_getFile(self):
404 """Tests retrieving a file from the database."""
405 res = self.store.getFile(self.file)
407 self.failUnlessEqual(res['hash'], self.hash)
409 def test_lookupHash(self):
410 """Tests looking up a hash in the database."""
411 res = self.store.lookupHash(self.hash)
413 self.failUnlessEqual(len(res), 1)
414 self.failUnlessEqual(res[0]['path'].path, self.file.path)
416 def test_isUnchanged(self):
417 """Tests checking if a file in the database is unchanged."""
418 res = self.store.isUnchanged(self.file)
422 res = self.store.isUnchanged(self.file)
423 self.failUnless(res == False)
424 res = self.store.isUnchanged(self.file)
425 self.failUnless(res is None)
427 def test_expiry(self):
428 """Tests retrieving the files from the database that have expired."""
429 res = self.store.expiredHashes(1)
430 self.failUnlessEqual(len(res.keys()), 0)
432 res = self.store.expiredHashes(1)
433 self.failUnlessEqual(len(res.keys()), 1)
434 self.failUnlessEqual(res.keys()[0], self.hash)
435 self.store.refreshHash(self.hash)
436 res = self.store.expiredHashes(1)
437 self.failUnlessEqual(len(res.keys()), 0)
439 def build_dirs(self):
440 for dir in self.dirs:
441 file = dir.preauthChild(self.testfile)
442 if not file.parent().exists():
443 file.parent().makedirs()
444 file.setContent(file.path)
446 self.store.storeFile(file, self.hash)
448 def test_multipleHashes(self):
449 """Tests looking up a hash with multiple files in the database."""
451 res = self.store.expiredHashes(1)
452 self.failUnlessEqual(len(res.keys()), 0)
453 res = self.store.lookupHash(self.hash)
455 self.failUnlessEqual(len(res), 4)
456 self.failUnlessEqual(res[0]['refreshed'], res[1]['refreshed'])
457 self.failUnlessEqual(res[0]['refreshed'], res[2]['refreshed'])
458 self.failUnlessEqual(res[0]['refreshed'], res[3]['refreshed'])
460 res = self.store.expiredHashes(1)
461 self.failUnlessEqual(len(res.keys()), 1)
462 self.failUnlessEqual(res.keys()[0], self.hash)
463 self.store.refreshHash(self.hash)
464 res = self.store.expiredHashes(1)
465 self.failUnlessEqual(len(res.keys()), 0)
467 def test_removeUntracked(self):
468 """Tests removing untracked files from the database."""
470 file = self.dirs[0].child('test.khashmir')
471 file.setContent(file.path)
473 self.store.storeFile(file, self.hash)
474 res = self.store.removeUntrackedFiles(self.dirs)
475 self.failUnlessEqual(len(res), 1, 'Got removed paths: %r' % res)
476 self.failUnlessEqual(res[0], self.file, 'Got removed paths: %r' % res)
477 res = self.store.removeUntrackedFiles(self.dirs)
478 self.failUnlessEqual(len(res), 0, 'Got removed paths: %r' % res)
480 res = self.store.removeUntrackedFiles(self.dirs)
481 self.failUnlessEqual(len(res), 1, 'Got removed paths: %r' % res)
482 self.failUnlessEqual(res[0], self.dirs[0].child('test.khashmir'), 'Got removed paths: %r' % res)
483 res = self.store.removeUntrackedFiles(self.dirs[1:])
484 self.failUnlessEqual(len(res), 1, 'Got removed paths: %r' % res)
485 self.failUnlessEqual(res[0], self.dirs[0].preauthChild(self.testfile), 'Got removed paths: %r' % res)
486 res = self.store.removeUntrackedFiles(self.dirs[:1])
487 self.failUnlessEqual(len(res), 2, 'Got removed paths: %r' % res)
488 self.failUnlessIn(self.dirs[1].preauthChild(self.testfile), res, 'Got removed paths: %r' % res)
489 self.failUnlessIn(self.dirs[2].preauthChild(self.testfile), res, 'Got removed paths: %r' % res)
492 self.directory.remove()