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
53 """Open a new connection to the existing database file"""
55 self.conn = sqlite.connect(database=self.db.path, detect_types=sqlite.PARSE_DECLTYPES)
58 raise DBExcept, "Couldn't open DB", traceback.format_exc()
60 def _createNewDB(self):
61 """Open a connection to a new database and create the necessary tables."""
62 if not self.db.parent().exists():
63 self.db.parent().makedirs()
64 self.conn = sqlite.connect(database=self.db.path, detect_types=sqlite.PARSE_DECLTYPES)
65 c = self.conn.cursor()
66 c.execute("CREATE TABLE files (path TEXT PRIMARY KEY UNIQUE, hashID INTEGER, " +
67 "size NUMBER, mtime NUMBER)")
68 c.execute("CREATE TABLE hashes (hashID INTEGER PRIMARY KEY AUTOINCREMENT, " +
69 "hash KHASH UNIQUE, pieces KHASH, " +
70 "piecehash KHASH, refreshed TIMESTAMP)")
71 c.execute("CREATE INDEX hashes_refreshed ON hashes(refreshed)")
72 c.execute("CREATE INDEX hashes_piecehash ON hashes(piecehash)")
76 def _removeChanged(self, file, row):
77 """If the file has changed or is missing, remove it from the DB.
79 @type file: L{twisted.python.filepath.FilePath}
80 @param file: the file to check
81 @type row: C{dictionary}-like object
82 @param row: contains the expected 'size' and 'mtime' of the file
84 @return: True if the file is unchanged, False if it is changed,
85 and None if it is missing
91 # Compare the current with the expected file properties
92 res = (row['size'] == file.getsize() and row['mtime'] == file.getmtime())
94 # Remove the file from the database
95 c = self.conn.cursor()
96 c.execute("DELETE FROM files WHERE path = ?", (file.path, ))
101 def storeFile(self, file, hash, pieces = ''):
102 """Store or update a file in the database.
104 @type file: L{twisted.python.filepath.FilePath}
105 @param file: the file to check
106 @type hash: C{string}
107 @param hash: the hash of the file
108 @type pieces: C{string}
109 @param pieces: the concatenated list of the hashes of the pieces of
110 the file (optional, defaults to the empty string)
111 @return: True if the hash was not in the database before
112 (so it needs to be added to the DHT)
114 # Hash the pieces to get the piecehash
117 piecehash = sha.new(pieces).digest()
119 # Check the database for the hash
120 c = self.conn.cursor()
121 c.execute("SELECT hashID, piecehash FROM hashes WHERE hash = ?", (khash(hash), ))
124 assert piecehash == row['piecehash']
126 hashID = row['hashID']
128 # Add the new hash to the database
129 c = self.conn.cursor()
130 c.execute("INSERT OR REPLACE INTO hashes (hash, pieces, piecehash, refreshed) VALUES (?, ?, ?, ?)",
131 (khash(hash), khash(pieces), khash(piecehash), datetime.now()))
136 # Add the file to the database
138 c.execute("INSERT OR REPLACE INTO files (path, hashID, size, mtime) VALUES (?, ?, ?, ?)",
139 (file.path, hashID, file.getsize(), file.getmtime()))
145 def getFile(self, file):
146 """Get a file from the database.
148 If it has changed or is missing, it is removed from the database.
150 @type file: L{twisted.python.filepath.FilePath}
151 @param file: the file to check
152 @return: dictionary of info for the file, False if changed, or
153 None if not in database or missing
155 c = self.conn.cursor()
156 c.execute("SELECT hash, size, mtime, pieces FROM files JOIN hashes USING (hashID) WHERE path = ?", (file.path, ))
160 res = self._removeChanged(file, row)
163 res['hash'] = row['hash']
164 res['size'] = row['size']
165 res['pieces'] = row['pieces']
169 def lookupHash(self, hash, filesOnly = False):
170 """Find a file by hash in the database.
172 If any found files have changed or are missing, they are removed
173 from the database. If filesOnly is False then it will also look for
174 piece string hashes if no files can be found.
176 @return: list of dictionaries of info for the found files
178 # Try to find the hash in the files table
179 c = self.conn.cursor()
180 c.execute("SELECT path, size, mtime, refreshed, pieces FROM files JOIN hashes USING (hashID) WHERE hash = ?", (khash(hash), ))
184 # Save the file to the list of found files
185 file = FilePath(row['path'])
186 res = self._removeChanged(file, row)
190 res['size'] = row['size']
191 res['refreshed'] = row['refreshed']
192 res['pieces'] = row['pieces']
196 if not filesOnly and not files:
197 # No files were found, so check the piecehashes as well
198 c.execute("SELECT refreshed, pieces, piecehash FROM hashes WHERE piecehash = ?", (khash(hash), ))
202 res['refreshed'] = row['refreshed']
203 res['pieces'] = row['pieces']
209 def isUnchanged(self, file):
210 """Check if a file in the file system has changed.
212 If it has changed, it is removed from the database.
214 @return: True if unchanged, False if changed, None if not in database
216 c = self.conn.cursor()
217 c.execute("SELECT size, mtime FROM files WHERE path = ?", (file.path, ))
219 return self._removeChanged(file, row)
221 def refreshHash(self, hash):
222 """Refresh the publishing time of a hash."""
223 c = self.conn.cursor()
224 c.execute("UPDATE hashes SET refreshed = ? WHERE hash = ?", (datetime.now(), khash(hash)))
227 def expiredHashes(self, expireAfter):
228 """Find files that need refreshing after expireAfter seconds.
230 For each hash that needs refreshing, finds all the files with that hash.
231 If the file has changed or is missing, it is removed from the table.
233 @return: dictionary with keys the hashes, values a list of FilePaths
235 t = datetime.now() - timedelta(seconds=expireAfter)
237 # Find all the hashes that need refreshing
238 c = self.conn.cursor()
239 c.execute("SELECT hashID, hash, pieces FROM hashes WHERE refreshed < ?", (t, ))
243 res = expired.setdefault(row['hash'], {})
244 res['hashID'] = row['hashID']
245 res['hash'] = row['hash']
246 res['pieces'] = row['pieces']
249 # Make sure there are still valid files for each hash
250 for hash in expired.values():
252 c.execute("SELECT path, size, mtime FROM files WHERE hashID = ?", (hash['hashID'], ))
255 res = self._removeChanged(FilePath(row['path']), row)
260 # Remove hashes for which no files are still available
261 del expired[hash['hash']]
262 c.execute("DELETE FROM hashes WHERE hashID = ?", (hash['hashID'], ))
269 def removeUntrackedFiles(self, dirs):
270 """Remove files that are no longer tracked by the program.
272 @type dirs: C{list} of L{twisted.python.filepath.FilePath}
273 @param dirs: a list of the directories that we are tracking
274 @return: list of files that were removed
276 assert len(dirs) >= 1
278 # Create a list of globs and an SQL statement for the directories
282 newdirs.append(dir.child('*').path)
283 sql += " path NOT GLOB ? AND"
286 # Get a listing of all the files that will be removed
287 c = self.conn.cursor()
288 c.execute("SELECT path FROM files " + sql, newdirs)
292 removed.append(FilePath(row['path']))
295 # Delete all the removed files from the database
297 c.execute("DELETE FROM files " + sql, newdirs)
303 """Close the database connection."""
306 class TestDB(unittest.TestCase):
307 """Tests for the khashmir database."""
310 db = FilePath('/tmp/khashmir.db')
311 hash = '\xca\xec\xb8\x0c\x00\xe7\x07\xf8~])\x8f\x9d\xe5_B\xff\x1a\xc4!'
312 directory = FilePath('/tmp/apt-p2p/')
313 file = FilePath('/tmp/apt-p2p/khashmir.test')
314 testfile = 'tmp/khashmir.test'
315 dirs = [FilePath('/tmp/apt-p2p/top1'),
316 FilePath('/tmp/apt-p2p/top2/sub1'),
317 FilePath('/tmp/apt-p2p/top2/sub2/')]
320 if not self.file.parent().exists():
321 self.file.parent().makedirs()
322 self.file.setContent('fgfhds')
324 self.store = DB(self.db)
325 self.store.storeFile(self.file, self.hash)
327 def test_openExistingDB(self):
328 """Tests opening an existing database."""
332 self.store = DB(self.db)
333 res = self.store.isUnchanged(self.file)
336 def test_getFile(self):
337 """Tests retrieving a file from the database."""
338 res = self.store.getFile(self.file)
340 self.failUnlessEqual(res['hash'], self.hash)
342 def test_lookupHash(self):
343 """Tests looking up a hash in the database."""
344 res = self.store.lookupHash(self.hash)
346 self.failUnlessEqual(len(res), 1)
347 self.failUnlessEqual(res[0]['path'].path, self.file.path)
349 def test_isUnchanged(self):
350 """Tests checking if a file in the database is unchanged."""
351 res = self.store.isUnchanged(self.file)
355 res = self.store.isUnchanged(self.file)
356 self.failUnless(res == False)
357 res = self.store.isUnchanged(self.file)
358 self.failUnless(res is None)
360 def test_expiry(self):
361 """Tests retrieving the files from the database that have expired."""
362 res = self.store.expiredHashes(1)
363 self.failUnlessEqual(len(res.keys()), 0)
365 res = self.store.expiredHashes(1)
366 self.failUnlessEqual(len(res.keys()), 1)
367 self.failUnlessEqual(res.keys()[0], self.hash)
368 self.store.refreshHash(self.hash)
369 res = self.store.expiredHashes(1)
370 self.failUnlessEqual(len(res.keys()), 0)
372 def build_dirs(self):
373 for dir in self.dirs:
374 file = dir.preauthChild(self.testfile)
375 if not file.parent().exists():
376 file.parent().makedirs()
377 file.setContent(file.path)
379 self.store.storeFile(file, self.hash)
381 def test_multipleHashes(self):
382 """Tests looking up a hash with multiple files in the database."""
384 res = self.store.expiredHashes(1)
385 self.failUnlessEqual(len(res.keys()), 0)
386 res = self.store.lookupHash(self.hash)
388 self.failUnlessEqual(len(res), 4)
389 self.failUnlessEqual(res[0]['refreshed'], res[1]['refreshed'])
390 self.failUnlessEqual(res[0]['refreshed'], res[2]['refreshed'])
391 self.failUnlessEqual(res[0]['refreshed'], res[3]['refreshed'])
393 res = self.store.expiredHashes(1)
394 self.failUnlessEqual(len(res.keys()), 1)
395 self.failUnlessEqual(res.keys()[0], self.hash)
396 self.store.refreshHash(self.hash)
397 res = self.store.expiredHashes(1)
398 self.failUnlessEqual(len(res.keys()), 0)
400 def test_removeUntracked(self):
401 """Tests removing untracked files from the database."""
403 res = self.store.removeUntrackedFiles(self.dirs)
404 self.failUnlessEqual(len(res), 1, 'Got removed paths: %r' % res)
405 self.failUnlessEqual(res[0], self.file, 'Got removed paths: %r' % res)
406 res = self.store.removeUntrackedFiles(self.dirs)
407 self.failUnlessEqual(len(res), 0, 'Got removed paths: %r' % res)
408 res = self.store.removeUntrackedFiles(self.dirs[1:])
409 self.failUnlessEqual(len(res), 1, 'Got removed paths: %r' % res)
410 self.failUnlessEqual(res[0], self.dirs[0].preauthChild(self.testfile), 'Got removed paths: %r' % res)
411 res = self.store.removeUntrackedFiles(self.dirs[:1])
412 self.failUnlessEqual(len(res), 2, 'Got removed paths: %r' % res)
413 self.failUnlessIn(self.dirs[1].preauthChild(self.testfile), res, 'Got removed paths: %r' % res)
414 self.failUnlessIn(self.dirs[2].preauthChild(self.testfile), res, 'Got removed paths: %r' % res)
417 self.directory.remove()