diff options
Diffstat (limited to 'src/leap/soledad/u1db/backends')
| -rw-r--r-- | src/leap/soledad/u1db/backends/__init__.py | 211 | ||||
| -rw-r--r-- | src/leap/soledad/u1db/backends/dbschema.sql | 42 | ||||
| -rw-r--r-- | src/leap/soledad/u1db/backends/inmemory.py | 469 | ||||
| -rw-r--r-- | src/leap/soledad/u1db/backends/sqlite_backend.py | 926 |
4 files changed, 1648 insertions, 0 deletions
diff --git a/src/leap/soledad/u1db/backends/__init__.py b/src/leap/soledad/u1db/backends/__init__.py new file mode 100644 index 00000000..c8e5adc6 --- /dev/null +++ b/src/leap/soledad/u1db/backends/__init__.py @@ -0,0 +1,211 @@ +# 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 <http://www.gnu.org/licenses/>. + +"""Abstract classes and common implementations for the backends.""" + +import re +try: + import simplejson as json +except ImportError: + import json # noqa +import uuid + +import u1db +from u1db import ( + errors, +) +import u1db.sync +from u1db.vectorclock import VectorClockRev + + +check_doc_id_re = re.compile("^" + u1db.DOC_ID_CONSTRAINTS + "$", re.UNICODE) + + +class CommonSyncTarget(u1db.sync.LocalSyncTarget): + pass + + +class CommonBackend(u1db.Database): + + document_size_limit = 0 + + def _allocate_doc_id(self): + """Generate a unique identifier for this document.""" + return 'D-' + uuid.uuid4().hex # 'D-' stands for document + + def _allocate_transaction_id(self): + return 'T-' + uuid.uuid4().hex # 'T-' stands for transaction + + def _allocate_doc_rev(self, old_doc_rev): + vcr = VectorClockRev(old_doc_rev) + vcr.increment(self._replica_uid) + return vcr.as_str() + + def _check_doc_id(self, doc_id): + if not check_doc_id_re.match(doc_id): + raise errors.InvalidDocId() + + def _check_doc_size(self, doc): + if not self.document_size_limit: + return + if doc.get_size() > self.document_size_limit: + raise errors.DocumentTooBig + + def _get_generation(self): + """Return the current generation. + + """ + raise NotImplementedError(self._get_generation) + + def _get_generation_info(self): + """Return the current generation and transaction id. + + """ + raise NotImplementedError(self._get_generation_info) + + def _get_doc(self, doc_id, check_for_conflicts=False): + """Extract the document from storage. + + This can return None if the document doesn't exist. + """ + raise NotImplementedError(self._get_doc) + + def _has_conflicts(self, doc_id): + """Return True if the doc has conflicts, False otherwise.""" + raise NotImplementedError(self._has_conflicts) + + def create_doc(self, content, doc_id=None): + json_string = json.dumps(content) + if doc_id is None: + doc_id = self._allocate_doc_id() + doc = self._factory(doc_id, None, json_string) + self.put_doc(doc) + return doc + + def create_doc_from_json(self, json, doc_id=None): + if doc_id is None: + doc_id = self._allocate_doc_id() + doc = self._factory(doc_id, None, json) + self.put_doc(doc) + return doc + + def _get_transaction_log(self): + """This is only for the test suite, it is not part of the api.""" + raise NotImplementedError(self._get_transaction_log) + + def _put_and_update_indexes(self, doc_id, old_doc, new_rev, content): + raise NotImplementedError(self._put_and_update_indexes) + + def get_docs(self, doc_ids, check_for_conflicts=True, + include_deleted=False): + for doc_id in doc_ids: + doc = self._get_doc( + doc_id, check_for_conflicts=check_for_conflicts) + if doc.is_tombstone() and not include_deleted: + continue + yield doc + + def _get_trans_id_for_gen(self, generation): + """Get the transaction id corresponding to a particular generation. + + Raises an InvalidGeneration when the generation does not exist. + + """ + raise NotImplementedError(self._get_trans_id_for_gen) + + def validate_gen_and_trans_id(self, generation, trans_id): + """Validate the generation and transaction id. + + Raises an InvalidGeneration when the generation does not exist, and an + InvalidTransactionId when it does but with a different transaction id. + + """ + if generation == 0: + return + known_trans_id = self._get_trans_id_for_gen(generation) + if known_trans_id != trans_id: + raise errors.InvalidTransactionId + + def _validate_source(self, other_replica_uid, other_generation, + other_transaction_id): + """Validate the new generation and transaction id. + + other_generation must be greater than what we have stored for this + replica, *or* it must be the same and the transaction_id must be the + same as well. + """ + (old_generation, + old_transaction_id) = self._get_replica_gen_and_trans_id( + other_replica_uid) + if other_generation < old_generation: + raise errors.InvalidGeneration + if other_generation > old_generation: + return + if other_transaction_id == old_transaction_id: + return + raise errors.InvalidTransactionId + + def _put_doc_if_newer(self, doc, save_conflict, replica_uid, replica_gen, + replica_trans_id=''): + cur_doc = self._get_doc(doc.doc_id) + doc_vcr = VectorClockRev(doc.rev) + if cur_doc is None: + cur_vcr = VectorClockRev(None) + else: + cur_vcr = VectorClockRev(cur_doc.rev) + self._validate_source(replica_uid, replica_gen, replica_trans_id) + if doc_vcr.is_newer(cur_vcr): + rev = doc.rev + self._prune_conflicts(doc, doc_vcr) + if doc.rev != rev: + # conflicts have been autoresolved + state = 'superseded' + else: + state = 'inserted' + self._put_and_update_indexes(cur_doc, doc) + elif doc.rev == cur_doc.rev: + # magical convergence + state = 'converged' + elif cur_vcr.is_newer(doc_vcr): + # Don't add this to seen_ids, because we have something newer, + # so we should send it back, and we should not generate a + # conflict + state = 'superseded' + elif cur_doc.same_content_as(doc): + # the documents have been edited to the same thing at both ends + doc_vcr.maximize(cur_vcr) + doc_vcr.increment(self._replica_uid) + doc.rev = doc_vcr.as_str() + self._put_and_update_indexes(cur_doc, doc) + state = 'superseded' + else: + state = 'conflicted' + if save_conflict: + self._force_doc_sync_conflict(doc) + if replica_uid is not None and replica_gen is not None: + self._do_set_replica_gen_and_trans_id( + replica_uid, replica_gen, replica_trans_id) + return state, self._get_generation() + + def _ensure_maximal_rev(self, cur_rev, extra_revs): + vcr = VectorClockRev(cur_rev) + for rev in extra_revs: + vcr.maximize(VectorClockRev(rev)) + vcr.increment(self._replica_uid) + return vcr.as_str() + + def set_document_size_limit(self, limit): + self.document_size_limit = limit diff --git a/src/leap/soledad/u1db/backends/dbschema.sql b/src/leap/soledad/u1db/backends/dbschema.sql new file mode 100644 index 00000000..ae027fc5 --- /dev/null +++ b/src/leap/soledad/u1db/backends/dbschema.sql @@ -0,0 +1,42 @@ +-- Database schema +CREATE TABLE transaction_log ( + generation INTEGER PRIMARY KEY AUTOINCREMENT, + doc_id TEXT NOT NULL, + transaction_id TEXT NOT NULL +); +CREATE TABLE document ( + doc_id TEXT PRIMARY KEY, + doc_rev TEXT NOT NULL, + content TEXT +); +CREATE TABLE document_fields ( + doc_id TEXT NOT NULL, + field_name TEXT NOT NULL, + value TEXT +); +CREATE INDEX document_fields_field_value_doc_idx + ON document_fields(field_name, value, doc_id); + +CREATE TABLE sync_log ( + replica_uid TEXT PRIMARY KEY, + known_generation INTEGER, + known_transaction_id TEXT +); +CREATE TABLE conflicts ( + doc_id TEXT, + doc_rev TEXT, + content TEXT, + CONSTRAINT conflicts_pkey PRIMARY KEY (doc_id, doc_rev) +); +CREATE TABLE index_definitions ( + name TEXT, + offset INT, + field TEXT, + CONSTRAINT index_definitions_pkey PRIMARY KEY (name, offset) +); +create index index_definitions_field on index_definitions(field); +CREATE TABLE u1db_config ( + name TEXT PRIMARY KEY, + value TEXT +); +INSERT INTO u1db_config VALUES ('sql_schema', '0'); diff --git a/src/leap/soledad/u1db/backends/inmemory.py b/src/leap/soledad/u1db/backends/inmemory.py new file mode 100644 index 00000000..a271bb37 --- /dev/null +++ b/src/leap/soledad/u1db/backends/inmemory.py @@ -0,0 +1,469 @@ +# 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 <http://www.gnu.org/licenses/>. + +"""The in-memory Database class for U1DB.""" + +try: + import simplejson as json +except ImportError: + import json # noqa + +from u1db import ( + Document, + errors, + query_parser, + vectorclock, + ) +from u1db.backends import CommonBackend, CommonSyncTarget + + +def get_prefix(value): + key_prefix = '\x01'.join(value) + return key_prefix.rstrip('*') + + +class InMemoryDatabase(CommonBackend): + """A database that only stores the data internally.""" + + def __init__(self, replica_uid, document_factory=None): + self._transaction_log = [] + self._docs = {} + # Map from doc_id => [(doc_rev, doc)] conflicts beyond 'winner' + self._conflicts = {} + self._other_generations = {} + self._indexes = {} + self._replica_uid = replica_uid + self._factory = document_factory or Document + + def _set_replica_uid(self, replica_uid): + """Force the replica_uid to be set.""" + self._replica_uid = replica_uid + + def set_document_factory(self, factory): + self._factory = factory + + def close(self): + # This is a no-op, We don't want to free the data because one client + # may be closing it, while another wants to inspect the results. + pass + + def _get_replica_gen_and_trans_id(self, other_replica_uid): + return self._other_generations.get(other_replica_uid, (0, '')) + + def _set_replica_gen_and_trans_id(self, other_replica_uid, + other_generation, other_transaction_id): + 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): + # TODO: to handle race conditions, we may want to check if the current + # value is greater than this new value. + self._other_generations[other_replica_uid] = (other_generation, + other_transaction_id) + + def get_sync_target(self): + return InMemorySyncTarget(self) + + def _get_transaction_log(self): + # snapshot! + return self._transaction_log[:] + + def _get_generation(self): + return len(self._transaction_log) + + def _get_generation_info(self): + if not self._transaction_log: + return 0, '' + return len(self._transaction_log), self._transaction_log[-1][1] + + def _get_trans_id_for_gen(self, generation): + if generation == 0: + return '' + if generation > len(self._transaction_log): + raise errors.InvalidGeneration + return self._transaction_log[generation - 1][1] + + 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) + 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 _put_and_update_indexes(self, old_doc, doc): + for index in self._indexes.itervalues(): + if old_doc is not None and not old_doc.is_tombstone(): + index.remove_json(old_doc.doc_id, old_doc.get_json()) + if not doc.is_tombstone(): + index.add_json(doc.doc_id, doc.get_json()) + trans_id = self._allocate_transaction_id() + self._docs[doc.doc_id] = (doc.rev, doc.get_json()) + self._transaction_log.append((doc.doc_id, trans_id)) + + def _get_doc(self, doc_id, check_for_conflicts=False): + try: + doc_rev, content = self._docs[doc_id] + except KeyError: + return None + doc = self._factory(doc_id, doc_rev, content) + if check_for_conflicts: + doc.has_conflicts = (doc.doc_id in self._conflicts) + return doc + + def _has_conflicts(self, doc_id): + return doc_id in self._conflicts + + 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): + """Return all documents in the database.""" + generation = self._get_generation() + results = [] + for doc_id, (doc_rev, content) in self._docs.items(): + if content is None and not include_deleted: + continue + doc = self._factory(doc_id, doc_rev, content) + doc.has_conflicts = self._has_conflicts(doc_id) + results.append(doc) + return (generation, results) + + def get_doc_conflicts(self, doc_id): + if doc_id not in self._conflicts: + return [] + result = [self._get_doc(doc_id)] + result[0].has_conflicts = True + result.extend([self._factory(doc_id, rev, content) + for rev, content in self._conflicts[doc_id]]) + return result + + def _replace_conflicts(self, doc, conflicts): + if not conflicts: + del self._conflicts[doc.doc_id] + else: + self._conflicts[doc.doc_id] = conflicts + doc.has_conflicts = bool(conflicts) + + def _prune_conflicts(self, doc, doc_vcr): + if self._has_conflicts(doc.doc_id): + autoresolved = False + remaining_conflicts = [] + cur_conflicts = self._conflicts[doc.doc_id] + for c_rev, c_doc in cur_conflicts: + c_vcr = vectorclock.VectorClockRev(c_rev) + if doc_vcr.is_newer(c_vcr): + continue + if doc.same_content_as(Document(doc.doc_id, c_rev, c_doc)): + doc_vcr.maximize(c_vcr) + autoresolved = True + continue + remaining_conflicts.append((c_rev, c_doc)) + if autoresolved: + doc_vcr.increment(self._replica_uid) + doc.rev = doc_vcr.as_str() + self._replace_conflicts(doc, remaining_conflicts) + + def resolve_doc(self, doc, conflicted_doc_revs): + cur_doc = self._get_doc(doc.doc_id) + if cur_doc is None: + cur_rev = None + else: + cur_rev = cur_doc.rev + new_rev = self._ensure_maximal_rev(cur_rev, conflicted_doc_revs) + superseded_revs = set(conflicted_doc_revs) + remaining_conflicts = [] + cur_conflicts = self._conflicts[doc.doc_id] + for c_rev, c_doc in cur_conflicts: + if c_rev in superseded_revs: + continue + remaining_conflicts.append((c_rev, c_doc)) + doc.rev = new_rev + if cur_rev in superseded_revs: + self._put_and_update_indexes(cur_doc, doc) + else: + remaining_conflicts.append((new_rev, doc.get_json())) + self._replace_conflicts(doc, remaining_conflicts) + + def delete_doc(self, doc): + if doc.doc_id not in self._docs: + raise errors.DocumentDoesNotExist + if self._docs[doc.doc_id][1] in ('null', None): + raise errors.DocumentAlreadyDeleted + doc.make_tombstone() + self.put_doc(doc) + + def create_index(self, index_name, *index_expressions): + if index_name in self._indexes: + if self._indexes[index_name]._definition == list( + index_expressions): + return + raise errors.IndexNameTakenError + index = InMemoryIndex(index_name, list(index_expressions)) + for doc_id, (doc_rev, doc) in self._docs.iteritems(): + if doc is not None: + index.add_json(doc_id, doc) + self._indexes[index_name] = index + + def delete_index(self, index_name): + del self._indexes[index_name] + + def list_indexes(self): + definitions = [] + for idx in self._indexes.itervalues(): + definitions.append((idx._name, idx._definition)) + return definitions + + def get_from_index(self, index_name, *key_values): + try: + index = self._indexes[index_name] + except KeyError: + raise errors.IndexDoesNotExist + doc_ids = index.lookup(key_values) + result = [] + for doc_id in doc_ids: + result.append(self._get_doc(doc_id, check_for_conflicts=True)) + return result + + def get_range_from_index(self, index_name, start_value=None, + end_value=None): + """Return all documents with key values in the specified range.""" + try: + index = self._indexes[index_name] + except KeyError: + raise errors.IndexDoesNotExist + if isinstance(start_value, basestring): + start_value = (start_value,) + if isinstance(end_value, basestring): + end_value = (end_value,) + doc_ids = index.lookup_range(start_value, end_value) + result = [] + for doc_id in doc_ids: + result.append(self._get_doc(doc_id, check_for_conflicts=True)) + return result + + def get_index_keys(self, index_name): + try: + index = self._indexes[index_name] + except KeyError: + raise errors.IndexDoesNotExist + keys = index.keys() + # XXX inefficiency warning + return list(set([tuple(key.split('\x01')) for key in keys])) + + def whats_changed(self, old_generation=0): + changes = [] + relevant_tail = self._transaction_log[old_generation:] + # We don't use len(self._transaction_log) because _transaction_log may + # get mutated by a concurrent operation. + cur_generation = old_generation + len(relevant_tail) + last_trans_id = '' + if relevant_tail: + last_trans_id = relevant_tail[-1][1] + elif self._transaction_log: + last_trans_id = self._transaction_log[-1][1] + seen = set() + generation = cur_generation + for doc_id, trans_id in reversed(relevant_tail): + if doc_id not in seen: + changes.append((doc_id, generation, trans_id)) + seen.add(doc_id) + generation -= 1 + changes.reverse() + return (cur_generation, last_trans_id, changes) + + def _force_doc_sync_conflict(self, doc): + my_doc = self._get_doc(doc.doc_id) + self._prune_conflicts(doc, vectorclock.VectorClockRev(doc.rev)) + self._conflicts.setdefault(doc.doc_id, []).append( + (my_doc.rev, my_doc.get_json())) + doc.has_conflicts = True + self._put_and_update_indexes(my_doc, doc) + + +class InMemoryIndex(object): + """Interface for managing an Index.""" + + def __init__(self, index_name, index_definition): + self._name = index_name + self._definition = index_definition + self._values = {} + parser = query_parser.Parser() + self._getters = parser.parse_all(self._definition) + + def evaluate_json(self, doc): + """Determine the 'key' after applying this index to the doc.""" + raw = json.loads(doc) + return self.evaluate(raw) + + def evaluate(self, obj): + """Evaluate a dict object, applying this definition.""" + all_rows = [[]] + for getter in self._getters: + new_rows = [] + keys = getter.get(obj) + if not keys: + return [] + for key in keys: + new_rows.extend([row + [key] for row in all_rows]) + all_rows = new_rows + all_rows = ['\x01'.join(row) for row in all_rows] + return all_rows + + def add_json(self, doc_id, doc): + """Add this json doc to the index.""" + keys = self.evaluate_json(doc) + if not keys: + return + for key in keys: + self._values.setdefault(key, []).append(doc_id) + + def remove_json(self, doc_id, doc): + """Remove this json doc from the index.""" + keys = self.evaluate_json(doc) + if keys: + for key in keys: + doc_ids = self._values[key] + doc_ids.remove(doc_id) + if not doc_ids: + del self._values[key] + + def _find_non_wildcards(self, values): + """Check if this should be a wildcard match. + + Further, this will raise an exception if the syntax is improperly + defined. + + :return: The offset of the last value we need to match against. + """ + if len(values) != len(self._definition): + raise errors.InvalidValueForIndex() + is_wildcard = False + last = 0 + for idx, val in enumerate(values): + if val.endswith('*'): + if val != '*': + # We have an 'x*' style wildcard + if is_wildcard: + # We were already in wildcard mode, so this is invalid + raise errors.InvalidGlobbing + last = idx + 1 + is_wildcard = True + else: + if is_wildcard: + # We were in wildcard mode, we can't follow that with + # non-wildcard + raise errors.InvalidGlobbing + last = idx + 1 + if not is_wildcard: + return -1 + return last + + def lookup(self, values): + """Find docs that match the values.""" + last = self._find_non_wildcards(values) + if last == -1: + return self._lookup_exact(values) + else: + return self._lookup_prefix(values[:last]) + + def lookup_range(self, start_values, end_values): + """Find docs within the range.""" + # TODO: Wildly inefficient, which is unlikely to be a problem for the + # inmemory implementation. + if start_values: + self._find_non_wildcards(start_values) + start_values = get_prefix(start_values) + if end_values: + if self._find_non_wildcards(end_values) == -1: + exact = True + else: + exact = False + end_values = get_prefix(end_values) + found = [] + for key, doc_ids in sorted(self._values.iteritems()): + if start_values and start_values > key: + continue + if end_values and end_values < key: + if exact: + break + else: + if not key.startswith(end_values): + break + found.extend(doc_ids) + return found + + def keys(self): + """Find the indexed keys.""" + return self._values.keys() + + def _lookup_prefix(self, value): + """Find docs that match the prefix string in values.""" + # TODO: We need a different data structure to make prefix style fast, + # some sort of sorted list would work, but a plain dict doesn't. + key_prefix = get_prefix(value) + all_doc_ids = [] + for key, doc_ids in sorted(self._values.iteritems()): + if key.startswith(key_prefix): + all_doc_ids.extend(doc_ids) + return all_doc_ids + + def _lookup_exact(self, value): + """Find docs that match exactly.""" + key = '\x01'.join(value) + if key in self._values: + return self._values[key] + return () + + +class InMemorySyncTarget(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_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_transaction_id) diff --git a/src/leap/soledad/u1db/backends/sqlite_backend.py b/src/leap/soledad/u1db/backends/sqlite_backend.py new file mode 100644 index 00000000..773213b5 --- /dev/null +++ b/src/leap/soledad/u1db/backends/sqlite_backend.py @@ -0,0 +1,926 @@ +# 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 <http://www.gnu.org/licenses/>. + +"""A U1DB implementation that uses SQLite 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, + ) + + +class SQLiteDatabase(CommonBackend): + """A U1DB implementation that uses SQLite as its persistence layer.""" + + _sqlite_registry = {} + + def __init__(self, sqlite_file, document_factory=None): + """Create a new sqlite file.""" + self._db_handle = dbapi2.connect(sqlite_file) + 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 SQLiteSyncTarget(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): + 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) + 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 SQLiteDatabase._sqlite_registry[v]( + sqlite_file, document_factory=document_factory) + + @classmethod + def open_database(cls, sqlite_file, create, backend_cls=None, + document_factory=None): + try: + return cls._open_database( + sqlite_file, document_factory=document_factory) + except errors.DatabaseDoesNotExist: + if not create: + raise + if backend_cls is None: + # default is SQLitePartialExpandDatabase + backend_cls = SQLitePartialExpandDatabase + return backend_cls(sqlite_file, document_factory=document_factory) + + @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 SQLiteDatabase. + + The attribute _index_storage_value will be used as the lookup key. + """ + SQLiteDatabase._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(SQLiteDatabase, 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 SQLiteSyncTarget(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 SQLitePartialExpandDatabase(SQLiteDatabase): + """An SQLite 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) + +SQLiteDatabase.register_implementation(SQLitePartialExpandDatabase) |