try: import simplejson as json except ImportError: import json # noqa from u1db import Document from u1db.remote.http_target import HTTPSyncTarget from u1db.remote.http_database import HTTPDatabase import base64 class NoDefaultKey(Exception): pass class LeapDocument(Document): """ LEAP Documents are standard u1db documents with cabability of returning an encrypted version of the document json string as well as setting document content based on an encrypted version of json string. """ def __init__(self, doc_id=None, rev=None, json='{}', has_conflicts=False, encrypted_json=None, default_key=None, gpg_wrapper=None): super(LeapDocument, self).__init__(doc_id, rev, json, has_conflicts) if gpg_wrapper: self._gpg = gpg_wrapper else: self._gpg = GPGWrapper() if encrypted_json: self.set_encrypted_json(encrypted_json) self._default_key = default_key def get_encrypted_json(self): """ Returns document's json serialization encrypted with user's public key. """ if self._default_key is None: raise NoDefaultKey() cyphertext = self._gpg.encrypt(self.get_json(), self._default_key, always_trust = True) # TODO: always trust? return json.dumps({'cyphertext' : str(cyphertext)}) def set_encrypted_json(self, encrypted_json): """ Set document's content based on encrypted version of json string. """ cyphertext = json.loads(encrypted_json)['cyphertext'] plaintext = str(self._gpg.decrypt(cyphertext)) return self.set_json(plaintext) class LeapDatabase(HTTPDatabase): """Implement the HTTP remote database API to a Leap server.""" @staticmethod def open_database(url, create): db = LeapDatabase(url) db.open(create) return db @staticmethod def delete_database(url): db = LeapDatabase(url) db._delete() db.close() def get_sync_target(self): st = LeapSyncTarget(self._url.geturl()) st._creds = self._creds return st class LeapSyncTarget(HTTPSyncTarget): def _parse_sync_stream(self, data, return_doc_cb, ensure_callback=None): """ Does the same as parent's method but ensures incoming content will be decrypted. """ parts = data.splitlines() # one at a time if not parts or parts[0] != '[': raise BrokenSyncStream data = parts[1:-1] comma = False if data: line, comma = utils.check_and_strip_comma(data[0]) res = json.loads(line) if ensure_callback and 'replica_uid' in res: ensure_callback(res['replica_uid']) for entry in data[1:]: if not comma: # missing in between comma raise BrokenSyncStream line, comma = utils.check_and_strip_comma(entry) entry = json.loads(line) doc = LeapDocument(entry['id'], entry['rev'], encrypted_json=entry['content']) return_doc_cb(doc, entry['gen'], entry['trans_id']) if parts[-1] != ']': try: partdic = json.loads(parts[-1]) except ValueError: pass else: if isinstance(partdic, dict): self._error(partdic) raise BrokenSyncStream if not data or comma: # no entries or bad extra comma raise BrokenSyncStream return res def sync_exchange(self, docs_by_generations, source_replica_uid, last_known_generation, last_known_trans_id, return_doc_cb, ensure_callback=None): """ Does the same as parent's method but encrypts content before syncing. """ self._ensure_connection() if self._trace_hook: # for tests self._trace_hook('sync_exchange') url = '%s/sync-from/%s' % (self._url.path, source_replica_uid) self._conn.putrequest('POST', url) self._conn.putheader('content-type', 'application/x-u1db-sync-stream') for header_name, header_value in self._sign_request('POST', url, {}): self._conn.putheader(header_name, header_value) entries = ['['] size = 1 def prepare(**dic): entry = comma + '\r\n' + json.dumps(dic) entries.append(entry) return len(entry) comma = '' size += prepare( last_known_generation=last_known_generation, last_known_trans_id=last_known_trans_id, ensure=ensure_callback is not None) comma = ',' for doc, gen, trans_id in docs_by_generations: size += prepare(id=doc.doc_id, rev=doc.rev, content=doc.get_encrypted_json(), gen=gen, trans_id=trans_id) entries.append('\r\n]') size += len(entries[-1]) self._conn.putheader('content-length', str(size)) self._conn.endheaders() for entry in entries: self._conn.send(entry) entries = None data, _ = self._response() res = self._parse_sync_stream(data, return_doc_cb, ensure_callback) data = None return res['new_generation'], res['new_transaction_id']