From 84e4bf0a810e097f7d4a4aed7bfc611050392afd Mon Sep 17 00:00:00 2001 From: drebs Date: Thu, 6 Dec 2012 11:08:11 -0200 Subject: Add sqlcipher backend. --- backends/sqlcipher.py | 954 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 954 insertions(+) create mode 100644 backends/sqlcipher.py diff --git a/backends/sqlcipher.py b/backends/sqlcipher.py new file mode 100644 index 00000000..24f47eed --- /dev/null +++ b/backends/sqlcipher.py @@ -0,0 +1,954 @@ +# Copyright 2011 Canonical Ltd. +# +# This file is part of u1db. +# +# u1db is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 +# as published by the Free Software Foundation. +# +# u1db is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with u1db. If not, see . + +"""A U1DB implementation that uses SQLCipher as its persistence layer.""" + +import errno +import os +try: + import simplejson as json +except ImportError: + import json # noqa +from sqlite3 import dbapi2 +import sys +import time +import uuid + +import pkg_resources + +from u1db.backends import CommonBackend, CommonSyncTarget +from u1db import ( + Document, + errors, + query_parser, + vectorclock, + ) + + +def open(path, create, document_factory=None, password=None): + """Open a database at the given location. + + Will raise u1db.errors.DatabaseDoesNotExist if create=False and the + database does not already exist. + + :param path: The filesystem path for the database to open. + :param create: True/False, should the database be created if it doesn't + already exist? + :param document_factory: A function that will be called with the same + parameters as Document.__init__. + :return: An instance of Database. + """ + from u1db.backends import sqlite_backend + return sqlite_backend.SQLCipherDatabase.open_database( + path, create=create, document_factory=document_factory, password=password) + + +class SQLCipherDatabase(CommonBackend): + """A U1DB implementation that uses SQLCipher as its persistence layer.""" + + _sqlite_registry = {} + + @classmethod + def set_pragma_key(cls, db_handle, key): + db_handle.cursor().execute("PRAGMA key = '%s'" % key) + + def __init__(self, sqlite_file, document_factory=None, password=None): + """Create a new sqlite file.""" + self._db_handle = dbapi2.connect(sqlite_file) + if password: + SQLiteDatabase.set_pragma_key(self._db_handle, password) + self._real_replica_uid = None + self._ensure_schema() + self._factory = document_factory or Document + + def set_document_factory(self, factory): + self._factory = factory + + def get_sync_target(self): + return SQLCipherSyncTarget(self) + + @classmethod + def _which_index_storage(cls, c): + try: + c.execute("SELECT value FROM u1db_config" + " WHERE name = 'index_storage'") + except dbapi2.OperationalError, e: + # The table does not exist yet + return None, e + else: + return c.fetchone()[0], None + + WAIT_FOR_PARALLEL_INIT_HALF_INTERVAL = 0.5 + + @classmethod + def _open_database(cls, sqlite_file, document_factory=None, password=None): + if not os.path.isfile(sqlite_file): + raise errors.DatabaseDoesNotExist() + tries = 2 + while True: + # Note: There seems to be a bug in sqlite 3.5.9 (with python2.6) + # where without re-opening the database on Windows, it + # doesn't see the transaction that was just committed + db_handle = dbapi2.connect(sqlite_file) + if password: + SQLiteDatabase.set_pragma_key(db_handle, password) + c = db_handle.cursor() + v, err = cls._which_index_storage(c) + db_handle.close() + if v is not None: + break + # possibly another process is initializing it, wait for it to be + # done + if tries == 0: + raise err # go for the richest error? + tries -= 1 + time.sleep(cls.WAIT_FOR_PARALLEL_INIT_HALF_INTERVAL) + return SQLCipherDatabase._sqlite_registry[v]( + sqlite_file, document_factory=document_factory) + + @classmethod + def open_database(cls, sqlite_file, create, backend_cls=None, + document_factory=None, password=None): + try: + return cls._open_database(sqlite_file, + document_factory=document_factory, + password=password) + except errors.DatabaseDoesNotExist: + if not create: + raise + if backend_cls is None: + # default is SQLCipherPartialExpandDatabase + backend_cls = SQLCipherPartialExpandDatabase + return backend_cls(sqlite_file, document_factory=document_factory, + password=password) + + @staticmethod + def delete_database(sqlite_file): + try: + os.unlink(sqlite_file) + except OSError as ex: + if ex.errno == errno.ENOENT: + raise errors.DatabaseDoesNotExist() + raise + + @staticmethod + def register_implementation(klass): + """Register that we implement an SQLCipherDatabase. + + The attribute _index_storage_value will be used as the lookup key. + """ + SQLCipherDatabase._sqlite_registry[klass._index_storage_value] = klass + + def _get_sqlite_handle(self): + """Get access to the underlying sqlite database. + + This should only be used by the test suite, etc, for examining the + state of the underlying database. + """ + return self._db_handle + + def _close_sqlite_handle(self): + """Release access to the underlying sqlite database.""" + self._db_handle.close() + + def close(self): + self._close_sqlite_handle() + + def _is_initialized(self, c): + """Check if this database has been initialized.""" + c.execute("PRAGMA case_sensitive_like=ON") + try: + c.execute("SELECT value FROM u1db_config" + " WHERE name = 'sql_schema'") + except dbapi2.OperationalError: + # The table does not exist yet + val = None + else: + val = c.fetchone() + if val is not None: + return True + return False + + def _initialize(self, c): + """Create the schema in the database.""" + #read the script with sql commands + # TODO: Change how we set up the dependency. Most likely use something + # like lp:dirspec to grab the file from a common resource + # directory. Doesn't specifically need to be handled until we get + # to the point of packaging this. + schema_content = pkg_resources.resource_string( + __name__, 'dbschema.sql') + # Note: We'd like to use c.executescript() here, but it seems that + # executescript always commits, even if you set + # isolation_level = None, so if we want to properly handle + # exclusive locking and rollbacks between processes, we need + # to execute it line-by-line + for line in schema_content.split(';'): + if not line: + continue + c.execute(line) + #add extra fields + self._extra_schema_init(c) + # A unique identifier should be set for this replica. Implementations + # don't have to strictly use uuid here, but we do want the uid to be + # unique amongst all databases that will sync with each other. + # We might extend this to using something with hostname for easier + # debugging. + self._set_replica_uid_in_transaction(uuid.uuid4().hex) + c.execute("INSERT INTO u1db_config VALUES" " ('index_storage', ?)", + (self._index_storage_value,)) + + def _ensure_schema(self): + """Ensure that the database schema has been created.""" + old_isolation_level = self._db_handle.isolation_level + c = self._db_handle.cursor() + if self._is_initialized(c): + return + try: + # autocommit/own mgmt of transactions + self._db_handle.isolation_level = None + with self._db_handle: + # only one execution path should initialize the db + c.execute("begin exclusive") + if self._is_initialized(c): + return + self._initialize(c) + finally: + self._db_handle.isolation_level = old_isolation_level + + def _extra_schema_init(self, c): + """Add any extra fields, etc to the basic table definitions.""" + + def _parse_index_definition(self, index_field): + """Parse a field definition for an index, returning a Getter.""" + # Note: We may want to keep a Parser object around, and cache the + # Getter objects for a greater length of time. Specifically, if + # you create a bunch of indexes, and then insert 50k docs, you'll + # re-parse the indexes between puts. The time to insert the docs + # is still likely to dominate put_doc time, though. + parser = query_parser.Parser() + getter = parser.parse(index_field) + return getter + + def _update_indexes(self, doc_id, raw_doc, getters, db_cursor): + """Update document_fields for a single document. + + :param doc_id: Identifier for this document + :param raw_doc: The python dict representation of the document. + :param getters: A list of [(field_name, Getter)]. Getter.get will be + called to evaluate the index definition for this document, and the + results will be inserted into the db. + :param db_cursor: An sqlite Cursor. + :return: None + """ + values = [] + for field_name, getter in getters: + for idx_value in getter.get(raw_doc): + values.append((doc_id, field_name, idx_value)) + if values: + db_cursor.executemany( + "INSERT INTO document_fields VALUES (?, ?, ?)", values) + + def _set_replica_uid(self, replica_uid): + """Force the replica_uid to be set.""" + with self._db_handle: + self._set_replica_uid_in_transaction(replica_uid) + + def _set_replica_uid_in_transaction(self, replica_uid): + """Set the replica_uid. A transaction should already be held.""" + c = self._db_handle.cursor() + c.execute("INSERT OR REPLACE INTO u1db_config" + " VALUES ('replica_uid', ?)", + (replica_uid,)) + self._real_replica_uid = replica_uid + + def _get_replica_uid(self): + if self._real_replica_uid is not None: + return self._real_replica_uid + c = self._db_handle.cursor() + c.execute("SELECT value FROM u1db_config WHERE name = 'replica_uid'") + val = c.fetchone() + if val is None: + return None + self._real_replica_uid = val[0] + return self._real_replica_uid + + _replica_uid = property(_get_replica_uid) + + def _get_generation(self): + c = self._db_handle.cursor() + c.execute('SELECT max(generation) FROM transaction_log') + val = c.fetchone()[0] + if val is None: + return 0 + return val + + def _get_generation_info(self): + c = self._db_handle.cursor() + c.execute( + 'SELECT max(generation), transaction_id FROM transaction_log ') + val = c.fetchone() + if val[0] is None: + return(0, '') + return val + + def _get_trans_id_for_gen(self, generation): + if generation == 0: + return '' + c = self._db_handle.cursor() + c.execute( + 'SELECT transaction_id FROM transaction_log WHERE generation = ?', + (generation,)) + val = c.fetchone() + if val is None: + raise errors.InvalidGeneration + return val[0] + + def _get_transaction_log(self): + c = self._db_handle.cursor() + c.execute("SELECT doc_id, transaction_id FROM transaction_log" + " ORDER BY generation") + return c.fetchall() + + def _get_doc(self, doc_id, check_for_conflicts=False): + """Get just the document content, without fancy handling.""" + c = self._db_handle.cursor() + if check_for_conflicts: + c.execute( + "SELECT document.doc_rev, document.content, " + "count(conflicts.doc_rev) FROM document LEFT OUTER JOIN " + "conflicts ON conflicts.doc_id = document.doc_id WHERE " + "document.doc_id = ? GROUP BY document.doc_id, " + "document.doc_rev, document.content;", (doc_id,)) + else: + c.execute( + "SELECT doc_rev, content, 0 FROM document WHERE doc_id = ?", + (doc_id,)) + val = c.fetchone() + if val is None: + return None + doc_rev, content, conflicts = val + doc = self._factory(doc_id, doc_rev, content) + doc.has_conflicts = conflicts > 0 + return doc + + def _has_conflicts(self, doc_id): + c = self._db_handle.cursor() + c.execute("SELECT 1 FROM conflicts WHERE doc_id = ? LIMIT 1", + (doc_id,)) + val = c.fetchone() + if val is None: + return False + else: + return True + + def get_doc(self, doc_id, include_deleted=False): + doc = self._get_doc(doc_id, check_for_conflicts=True) + if doc is None: + return None + if doc.is_tombstone() and not include_deleted: + return None + return doc + + def get_all_docs(self, include_deleted=False): + """Get all documents from the database.""" + generation = self._get_generation() + results = [] + c = self._db_handle.cursor() + c.execute( + "SELECT document.doc_id, document.doc_rev, document.content, " + "count(conflicts.doc_rev) FROM document LEFT OUTER JOIN conflicts " + "ON conflicts.doc_id = document.doc_id GROUP BY document.doc_id, " + "document.doc_rev, document.content;") + rows = c.fetchall() + for doc_id, doc_rev, content, conflicts in rows: + if content is None and not include_deleted: + continue + doc = self._factory(doc_id, doc_rev, content) + doc.has_conflicts = conflicts > 0 + results.append(doc) + return (generation, results) + + def put_doc(self, doc): + if doc.doc_id is None: + raise errors.InvalidDocId() + self._check_doc_id(doc.doc_id) + self._check_doc_size(doc) + with self._db_handle: + old_doc = self._get_doc(doc.doc_id, check_for_conflicts=True) + if old_doc and old_doc.has_conflicts: + raise errors.ConflictedDoc() + if old_doc and doc.rev is None and old_doc.is_tombstone(): + new_rev = self._allocate_doc_rev(old_doc.rev) + else: + if old_doc is not None: + if old_doc.rev != doc.rev: + raise errors.RevisionConflict() + else: + if doc.rev is not None: + raise errors.RevisionConflict() + new_rev = self._allocate_doc_rev(doc.rev) + doc.rev = new_rev + self._put_and_update_indexes(old_doc, doc) + return new_rev + + def _expand_to_fields(self, doc_id, base_field, raw_doc, save_none): + """Convert a dict representation into named fields. + + So something like: {'key1': 'val1', 'key2': 'val2'} + gets converted into: [(doc_id, 'key1', 'val1', 0) + (doc_id, 'key2', 'val2', 0)] + :param doc_id: Just added to every record. + :param base_field: if set, these are nested keys, so each field should + be appropriately prefixed. + :param raw_doc: The python dictionary. + """ + # TODO: Handle lists + values = [] + for field_name, value in raw_doc.iteritems(): + if value is None and not save_none: + continue + if base_field: + full_name = base_field + '.' + field_name + else: + full_name = field_name + if value is None or isinstance(value, (int, float, basestring)): + values.append((doc_id, full_name, value, len(values))) + else: + subvalues = self._expand_to_fields(doc_id, full_name, value, + save_none) + for _, subfield_name, val, _ in subvalues: + values.append((doc_id, subfield_name, val, len(values))) + return values + + def _put_and_update_indexes(self, old_doc, doc): + """Actually insert a document into the database. + + This both updates the existing documents content, and any indexes that + refer to this document. + """ + raise NotImplementedError(self._put_and_update_indexes) + + def whats_changed(self, old_generation=0): + c = self._db_handle.cursor() + c.execute("SELECT generation, doc_id, transaction_id" + " FROM transaction_log" + " WHERE generation > ? ORDER BY generation DESC", + (old_generation,)) + results = c.fetchall() + cur_gen = old_generation + seen = set() + changes = [] + newest_trans_id = '' + for generation, doc_id, trans_id in results: + if doc_id not in seen: + changes.append((doc_id, generation, trans_id)) + seen.add(doc_id) + if changes: + cur_gen = changes[0][1] # max generation + newest_trans_id = changes[0][2] + changes.reverse() + else: + c.execute("SELECT generation, transaction_id" + " FROM transaction_log ORDER BY generation DESC LIMIT 1") + results = c.fetchone() + if not results: + cur_gen = 0 + newest_trans_id = '' + else: + cur_gen, newest_trans_id = results + + return cur_gen, newest_trans_id, changes + + def delete_doc(self, doc): + with self._db_handle: + old_doc = self._get_doc(doc.doc_id, check_for_conflicts=True) + if old_doc is None: + raise errors.DocumentDoesNotExist + if old_doc.rev != doc.rev: + raise errors.RevisionConflict() + if old_doc.is_tombstone(): + raise errors.DocumentAlreadyDeleted + if old_doc.has_conflicts: + raise errors.ConflictedDoc() + new_rev = self._allocate_doc_rev(doc.rev) + doc.rev = new_rev + doc.make_tombstone() + self._put_and_update_indexes(old_doc, doc) + return new_rev + + def _get_conflicts(self, doc_id): + c = self._db_handle.cursor() + c.execute("SELECT doc_rev, content FROM conflicts WHERE doc_id = ?", + (doc_id,)) + return [self._factory(doc_id, doc_rev, content) + for doc_rev, content in c.fetchall()] + + def get_doc_conflicts(self, doc_id): + with self._db_handle: + conflict_docs = self._get_conflicts(doc_id) + if not conflict_docs: + return [] + this_doc = self._get_doc(doc_id) + this_doc.has_conflicts = True + return [this_doc] + conflict_docs + + def _get_replica_gen_and_trans_id(self, other_replica_uid): + c = self._db_handle.cursor() + c.execute("SELECT known_generation, known_transaction_id FROM sync_log" + " WHERE replica_uid = ?", + (other_replica_uid,)) + val = c.fetchone() + if val is None: + other_gen = 0 + trans_id = '' + else: + other_gen = val[0] + trans_id = val[1] + return other_gen, trans_id + + def _set_replica_gen_and_trans_id(self, other_replica_uid, + other_generation, other_transaction_id): + with self._db_handle: + self._do_set_replica_gen_and_trans_id( + other_replica_uid, other_generation, other_transaction_id) + + def _do_set_replica_gen_and_trans_id(self, other_replica_uid, + other_generation, + other_transaction_id): + c = self._db_handle.cursor() + c.execute("INSERT OR REPLACE INTO sync_log VALUES (?, ?, ?)", + (other_replica_uid, other_generation, + other_transaction_id)) + + def _put_doc_if_newer(self, doc, save_conflict, replica_uid=None, + replica_gen=None, replica_trans_id=None): + with self._db_handle: + return super(SQLCipherDatabase, self)._put_doc_if_newer(doc, + save_conflict=save_conflict, + replica_uid=replica_uid, replica_gen=replica_gen, + replica_trans_id=replica_trans_id) + + def _add_conflict(self, c, doc_id, my_doc_rev, my_content): + c.execute("INSERT INTO conflicts VALUES (?, ?, ?)", + (doc_id, my_doc_rev, my_content)) + + def _delete_conflicts(self, c, doc, conflict_revs): + deleting = [(doc.doc_id, c_rev) for c_rev in conflict_revs] + c.executemany("DELETE FROM conflicts" + " WHERE doc_id=? AND doc_rev=?", deleting) + doc.has_conflicts = self._has_conflicts(doc.doc_id) + + def _prune_conflicts(self, doc, doc_vcr): + if self._has_conflicts(doc.doc_id): + autoresolved = False + c_revs_to_prune = [] + for c_doc in self._get_conflicts(doc.doc_id): + c_vcr = vectorclock.VectorClockRev(c_doc.rev) + if doc_vcr.is_newer(c_vcr): + c_revs_to_prune.append(c_doc.rev) + elif doc.same_content_as(c_doc): + c_revs_to_prune.append(c_doc.rev) + doc_vcr.maximize(c_vcr) + autoresolved = True + if autoresolved: + doc_vcr.increment(self._replica_uid) + doc.rev = doc_vcr.as_str() + c = self._db_handle.cursor() + self._delete_conflicts(c, doc, c_revs_to_prune) + + def _force_doc_sync_conflict(self, doc): + my_doc = self._get_doc(doc.doc_id) + c = self._db_handle.cursor() + self._prune_conflicts(doc, vectorclock.VectorClockRev(doc.rev)) + self._add_conflict(c, doc.doc_id, my_doc.rev, my_doc.get_json()) + doc.has_conflicts = True + self._put_and_update_indexes(my_doc, doc) + + def resolve_doc(self, doc, conflicted_doc_revs): + with self._db_handle: + cur_doc = self._get_doc(doc.doc_id) + # TODO: https://bugs.launchpad.net/u1db/+bug/928274 + # I think we have a logic bug in resolve_doc + # Specifically, cur_doc.rev is always in the final vector + # clock of revisions that we supersede, even if it wasn't in + # conflicted_doc_revs. We still add it as a conflict, but the + # fact that _put_doc_if_newer propagates resolutions means I + # think that conflict could accidentally be resolved. We need + # to add a test for this case first. (create a rev, create a + # conflict, create another conflict, resolve the first rev + # and first conflict, then make sure that the resolved + # rev doesn't supersede the second conflict rev.) It *might* + # not matter, because the superseding rev is in as a + # conflict, but it does seem incorrect + new_rev = self._ensure_maximal_rev(cur_doc.rev, + conflicted_doc_revs) + superseded_revs = set(conflicted_doc_revs) + c = self._db_handle.cursor() + doc.rev = new_rev + if cur_doc.rev in superseded_revs: + self._put_and_update_indexes(cur_doc, doc) + else: + self._add_conflict(c, doc.doc_id, new_rev, doc.get_json()) + # TODO: Is there some way that we could construct a rev that would + # end up in superseded_revs, such that we add a conflict, and + # then immediately delete it? + self._delete_conflicts(c, doc, superseded_revs) + + def list_indexes(self): + """Return the list of indexes and their definitions.""" + c = self._db_handle.cursor() + # TODO: How do we test the ordering? + c.execute("SELECT name, field FROM index_definitions" + " ORDER BY name, offset") + definitions = [] + cur_name = None + for name, field in c.fetchall(): + if cur_name != name: + definitions.append((name, [])) + cur_name = name + definitions[-1][-1].append(field) + return definitions + + def _get_index_definition(self, index_name): + """Return the stored definition for a given index_name.""" + c = self._db_handle.cursor() + c.execute("SELECT field FROM index_definitions" + " WHERE name = ? ORDER BY offset", (index_name,)) + fields = [x[0] for x in c.fetchall()] + if not fields: + raise errors.IndexDoesNotExist + return fields + + @staticmethod + def _strip_glob(value): + """Remove the trailing * from a value.""" + assert value[-1] == '*' + return value[:-1] + + def _format_query(self, definition, key_values): + # First, build the definition. We join the document_fields table + # against itself, as many times as the 'width' of our definition. + # We then do a query for each key_value, one-at-a-time. + # Note: All of these strings are static, we could cache them, etc. + tables = ["document_fields d%d" % i for i in range(len(definition))] + novalue_where = ["d.doc_id = d%d.doc_id" + " AND d%d.field_name = ?" + % (i, i) for i in range(len(definition))] + wildcard_where = [novalue_where[i] + + (" AND d%d.value NOT NULL" % (i,)) + for i in range(len(definition))] + exact_where = [novalue_where[i] + + (" AND d%d.value = ?" % (i,)) + for i in range(len(definition))] + like_where = [novalue_where[i] + + (" AND d%d.value GLOB ?" % (i,)) + for i in range(len(definition))] + is_wildcard = False + # Merge the lists together, so that: + # [field1, field2, field3], [val1, val2, val3] + # Becomes: + # (field1, val1, field2, val2, field3, val3) + args = [] + where = [] + for idx, (field, value) in enumerate(zip(definition, key_values)): + args.append(field) + if value.endswith('*'): + if value == '*': + where.append(wildcard_where[idx]) + else: + # This is a glob match + if is_wildcard: + # We can't have a partial wildcard following + # another wildcard + raise errors.InvalidGlobbing + where.append(like_where[idx]) + args.append(value) + is_wildcard = True + else: + if is_wildcard: + raise errors.InvalidGlobbing + where.append(exact_where[idx]) + args.append(value) + statement = ( + "SELECT d.doc_id, d.doc_rev, d.content, count(c.doc_rev) FROM " + "document d, %s LEFT OUTER JOIN conflicts c ON c.doc_id = " + "d.doc_id WHERE %s GROUP BY d.doc_id, d.doc_rev, d.content ORDER " + "BY %s;" % (', '.join(tables), ' AND '.join(where), ', '.join( + ['d%d.value' % i for i in range(len(definition))]))) + return statement, args + + def get_from_index(self, index_name, *key_values): + definition = self._get_index_definition(index_name) + if len(key_values) != len(definition): + raise errors.InvalidValueForIndex() + statement, args = self._format_query(definition, key_values) + c = self._db_handle.cursor() + try: + c.execute(statement, tuple(args)) + except dbapi2.OperationalError, e: + raise dbapi2.OperationalError(str(e) + + '\nstatement: %s\nargs: %s\n' % (statement, args)) + res = c.fetchall() + results = [] + for row in res: + doc = self._factory(row[0], row[1], row[2]) + doc.has_conflicts = row[3] > 0 + results.append(doc) + return results + + def _format_range_query(self, definition, start_value, end_value): + tables = ["document_fields d%d" % i for i in range(len(definition))] + novalue_where = [ + "d.doc_id = d%d.doc_id AND d%d.field_name = ?" % (i, i) for i in + range(len(definition))] + wildcard_where = [ + novalue_where[i] + (" AND d%d.value NOT NULL" % (i,)) for i in + range(len(definition))] + like_where = [ + novalue_where[i] + ( + " AND (d%d.value < ? OR d%d.value GLOB ?)" % (i, i)) for i in + range(len(definition))] + range_where_lower = [ + novalue_where[i] + (" AND d%d.value >= ?" % (i,)) for i in + range(len(definition))] + range_where_upper = [ + novalue_where[i] + (" AND d%d.value <= ?" % (i,)) for i in + range(len(definition))] + args = [] + where = [] + if start_value: + if isinstance(start_value, basestring): + start_value = (start_value,) + if len(start_value) != len(definition): + raise errors.InvalidValueForIndex() + is_wildcard = False + for idx, (field, value) in enumerate(zip(definition, start_value)): + args.append(field) + if value.endswith('*'): + if value == '*': + where.append(wildcard_where[idx]) + else: + # This is a glob match + if is_wildcard: + # We can't have a partial wildcard following + # another wildcard + raise errors.InvalidGlobbing + where.append(range_where_lower[idx]) + args.append(self._strip_glob(value)) + is_wildcard = True + else: + if is_wildcard: + raise errors.InvalidGlobbing + where.append(range_where_lower[idx]) + args.append(value) + if end_value: + if isinstance(end_value, basestring): + end_value = (end_value,) + if len(end_value) != len(definition): + raise errors.InvalidValueForIndex() + is_wildcard = False + for idx, (field, value) in enumerate(zip(definition, end_value)): + args.append(field) + if value.endswith('*'): + if value == '*': + where.append(wildcard_where[idx]) + else: + # This is a glob match + if is_wildcard: + # We can't have a partial wildcard following + # another wildcard + raise errors.InvalidGlobbing + where.append(like_where[idx]) + args.append(self._strip_glob(value)) + args.append(value) + is_wildcard = True + else: + if is_wildcard: + raise errors.InvalidGlobbing + where.append(range_where_upper[idx]) + args.append(value) + statement = ( + "SELECT d.doc_id, d.doc_rev, d.content, count(c.doc_rev) FROM " + "document d, %s LEFT OUTER JOIN conflicts c ON c.doc_id = " + "d.doc_id WHERE %s GROUP BY d.doc_id, d.doc_rev, d.content ORDER " + "BY %s;" % (', '.join(tables), ' AND '.join(where), ', '.join( + ['d%d.value' % i for i in range(len(definition))]))) + return statement, args + + def get_range_from_index(self, index_name, start_value=None, + end_value=None): + """Return all documents with key values in the specified range.""" + definition = self._get_index_definition(index_name) + statement, args = self._format_range_query( + definition, start_value, end_value) + c = self._db_handle.cursor() + try: + c.execute(statement, tuple(args)) + except dbapi2.OperationalError, e: + raise dbapi2.OperationalError(str(e) + + '\nstatement: %s\nargs: %s\n' % (statement, args)) + res = c.fetchall() + results = [] + for row in res: + doc = self._factory(row[0], row[1], row[2]) + doc.has_conflicts = row[3] > 0 + results.append(doc) + return results + + def get_index_keys(self, index_name): + c = self._db_handle.cursor() + definition = self._get_index_definition(index_name) + value_fields = ', '.join([ + 'd%d.value' % i for i in range(len(definition))]) + tables = ["document_fields d%d" % i for i in range(len(definition))] + novalue_where = [ + "d.doc_id = d%d.doc_id AND d%d.field_name = ?" % (i, i) for i in + range(len(definition))] + where = [ + novalue_where[i] + (" AND d%d.value NOT NULL" % (i,)) for i in + range(len(definition))] + statement = ( + "SELECT %s FROM document d, %s WHERE %s GROUP BY %s;" % ( + value_fields, ', '.join(tables), ' AND '.join(where), + value_fields)) + try: + c.execute(statement, tuple(definition)) + except dbapi2.OperationalError, e: + raise dbapi2.OperationalError(str(e) + + '\nstatement: %s\nargs: %s\n' % (statement, tuple(definition))) + return c.fetchall() + + def delete_index(self, index_name): + with self._db_handle: + c = self._db_handle.cursor() + c.execute("DELETE FROM index_definitions WHERE name = ?", + (index_name,)) + c.execute( + "DELETE FROM document_fields WHERE document_fields.field_name " + " NOT IN (SELECT field from index_definitions)") + + +class SQLCipherSyncTarget(CommonSyncTarget): + + def get_sync_info(self, source_replica_uid): + source_gen, source_trans_id = self._db._get_replica_gen_and_trans_id( + source_replica_uid) + my_gen, my_trans_id = self._db._get_generation_info() + return ( + self._db._replica_uid, my_gen, my_trans_id, source_gen, + source_trans_id) + + def record_sync_info(self, source_replica_uid, source_replica_generation, + source_replica_transaction_id): + if self._trace_hook: + self._trace_hook('record_sync_info') + self._db._set_replica_gen_and_trans_id( + source_replica_uid, source_replica_generation, + source_replica_transaction_id) + + +class SQLCipherPartialExpandDatabase(SQLCipherDatabase): + """An SQLCipher Backend that expands documents into a document_field table. + + It stores the original document text in document.doc. For fields that are + indexed, the data goes into document_fields. + """ + + _index_storage_value = 'expand referenced' + + def _get_indexed_fields(self): + """Determine what fields are indexed.""" + c = self._db_handle.cursor() + c.execute("SELECT field FROM index_definitions") + return set([x[0] for x in c.fetchall()]) + + def _evaluate_index(self, raw_doc, field): + parser = query_parser.Parser() + getter = parser.parse(field) + return getter.get(raw_doc) + + def _put_and_update_indexes(self, old_doc, doc): + c = self._db_handle.cursor() + if doc and not doc.is_tombstone(): + raw_doc = json.loads(doc.get_json()) + else: + raw_doc = {} + if old_doc is not None: + c.execute("UPDATE document SET doc_rev=?, content=?" + " WHERE doc_id = ?", + (doc.rev, doc.get_json(), doc.doc_id)) + c.execute("DELETE FROM document_fields WHERE doc_id = ?", + (doc.doc_id,)) + else: + c.execute("INSERT INTO document (doc_id, doc_rev, content)" + " VALUES (?, ?, ?)", + (doc.doc_id, doc.rev, doc.get_json())) + indexed_fields = self._get_indexed_fields() + if indexed_fields: + # It is expected that len(indexed_fields) is shorter than + # len(raw_doc) + getters = [(field, self._parse_index_definition(field)) + for field in indexed_fields] + self._update_indexes(doc.doc_id, raw_doc, getters, c) + trans_id = self._allocate_transaction_id() + c.execute("INSERT INTO transaction_log(doc_id, transaction_id)" + " VALUES (?, ?)", (doc.doc_id, trans_id)) + + def create_index(self, index_name, *index_expressions): + with self._db_handle: + c = self._db_handle.cursor() + cur_fields = self._get_indexed_fields() + definition = [(index_name, idx, field) + for idx, field in enumerate(index_expressions)] + try: + c.executemany("INSERT INTO index_definitions VALUES (?, ?, ?)", + definition) + except dbapi2.IntegrityError as e: + stored_def = self._get_index_definition(index_name) + if stored_def == [x[-1] for x in definition]: + return + raise errors.IndexNameTakenError, e, sys.exc_info()[2] + new_fields = set( + [f for f in index_expressions if f not in cur_fields]) + if new_fields: + self._update_all_indexes(new_fields) + + def _iter_all_docs(self): + c = self._db_handle.cursor() + c.execute("SELECT doc_id, content FROM document") + while True: + next_rows = c.fetchmany() + if not next_rows: + break + for row in next_rows: + yield row + + def _update_all_indexes(self, new_fields): + """Iterate all the documents, and add content to document_fields. + + :param new_fields: The index definitions that need to be added. + """ + getters = [(field, self._parse_index_definition(field)) + for field in new_fields] + c = self._db_handle.cursor() + for doc_id, doc in self._iter_all_docs(): + if doc is None: + continue + raw_doc = json.loads(doc) + self._update_indexes(doc_id, raw_doc, getters, c) + +SQLCipherDatabase.register_implementation(SQLCipherPartialExpandDatabase) -- cgit v1.2.3