diff options
Diffstat (limited to 'client/src/leap/soledad/client/http_target/api.py')
| -rw-r--r-- | client/src/leap/soledad/client/http_target/api.py | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/client/src/leap/soledad/client/http_target/api.py b/client/src/leap/soledad/client/http_target/api.py new file mode 100644 index 00000000..9e677304 --- /dev/null +++ b/client/src/leap/soledad/client/http_target/api.py @@ -0,0 +1,251 @@ +import json +import base64 + +from uuid import uuid4 +from u1db import SyncTarget + +from twisted.web.error import Error +from twisted.internet import defer + +from leap.soledad.common.errors import InvalidAuthTokenError +from leap.soledad.client.http_target.support import readBody + +from leap.common.http import HTTPClient + + +class SyncTargetAPI(SyncTarget): + + def __init__(self, url, source_replica_uid, creds, crypto, cert_file, + sync_db=None, sync_enc_pool=None): + """ + Initialize the sync target. + + :param url: The server sync url. + :type url: str + :param source_replica_uid: The source replica uid which we use when + deferring decryption. + :type source_replica_uid: str + :param creds: A dictionary containing the uuid and token. + :type creds: creds + :param crypto: An instance of SoledadCrypto so we can encrypt/decrypt + document contents when syncing. + :type crypto: soledad.crypto.SoledadCrypto + :param cert_file: Path to the certificate of the ca used to validate + the SSL certificate used by the remote soledad + server. + :type cert_file: str + :param sync_db: Optional. handler for the db with the symmetric + encryption of the syncing documents. If + None, encryption will be done in-place, + instead of retreiving it from the dedicated + database. + :type sync_db: Sqlite handler + :param sync_enc_pool: The encryption pool to use to defer encryption. + If None is passed the encryption will not be + deferred. + :type sync_enc_pool: leap.soledad.client.encdecpool.SyncEncrypterPool + """ + if url.endswith("/"): + url = url[:-1] + self._url = str(url) + "/sync-from/" + str(source_replica_uid) + self.source_replica_uid = source_replica_uid + self._auth_header = None + self.set_creds(creds) + self._crypto = crypto + self._sync_db = sync_db + self._sync_enc_pool = sync_enc_pool + self._insert_doc_cb = None + # asynchronous encryption/decryption attributes + self._decryption_callback = None + self._sync_decr_pool = None + self._http = HTTPClient(cert_file) + + def close(self): + self._http.close() + + def set_creds(self, creds): + """ + Update credentials. + + :param creds: A dictionary containing the uuid and token. + :type creds: dict + """ + uuid = creds['token']['uuid'] + token = creds['token']['token'] + auth = '%s:%s' % (uuid, token) + b64_token = base64.b64encode(auth) + self._auth_header = {'Authorization': ['Token %s' % b64_token]} + + @property + def _base_header(self): + return self._auth_header.copy() if self._auth_header else {} + + @property + def _defer_encryption(self): + return self._sync_enc_pool is not None + + def _http_request(self, url, method='GET', body=None, headers=None, content_type=None): + headers = headers or self._base_header + if content_type: + headers.update({'content-type': [content_type]}) + d = self._http.request(url, method, body, headers, readBody) + d.addErrback(_unauth_to_invalid_token_error) + return d + + @defer.inlineCallbacks + def get_sync_info(self, source_replica_uid): + """ + Return information about known state of remote database. + + Return the replica_uid and the current database generation of the + remote database, and its last-seen database generation for the client + replica. + + :param source_replica_uid: The client-size replica uid. + :type source_replica_uid: str + + :return: A deferred which fires with (target_replica_uid, + target_replica_generation, target_trans_id, + source_replica_last_known_generation, + source_replica_last_known_transaction_id) + :rtype: twisted.internet.defer.Deferred + """ + raw = yield self._http_request(self._url) + res = json.loads(raw) + defer.returnValue([ + res['target_replica_uid'], + res['target_replica_generation'], + res['target_replica_transaction_id'], + res['source_replica_generation'], + res['source_transaction_id'] + ]) + + def record_sync_info( + self, source_replica_uid, source_replica_generation, + source_replica_transaction_id): + """ + Record tip information for another replica. + + After sync_exchange has been processed, the caller will have + received new content from this replica. This call allows the + source replica instigating the sync to inform us what their + generation became after applying the documents we returned. + + This is used to allow future sync operations to not need to repeat data + that we just talked about. It also means that if this is called at the + wrong time, there can be database records that will never be + synchronized. + + :param source_replica_uid: The identifier for the source replica. + :type source_replica_uid: str + :param source_replica_generation: The database generation for the + source replica. + :type source_replica_generation: int + :param source_replica_transaction_id: The transaction id associated + with the source replica + generation. + :type source_replica_transaction_id: str + + :return: A deferred which fires with the result of the query. + :rtype: twisted.internet.defer.Deferred + """ + data = json.dumps({ + 'generation': source_replica_generation, + 'transaction_id': source_replica_transaction_id + }) + return self._http_request( + self._url, + method='PUT', + body=data, + content_type='application/json') + + @defer.inlineCallbacks + def sync_exchange(self, docs_by_generation, source_replica_uid, + last_known_generation, last_known_trans_id, + insert_doc_cb, ensure_callback=None, + defer_decryption=True, sync_id=None): + """ + Find out which documents the remote database does not know about, + encrypt and send them. After that, receive documents from the remote + database. + + :param docs_by_generations: A list of (doc_id, generation, trans_id) + of local documents that were changed since + the last local generation the remote + replica knows about. + :type docs_by_generations: list of tuples + + :param source_replica_uid: The uid of the source replica. + :type source_replica_uid: str + + :param last_known_generation: Target's last known generation. + :type last_known_generation: int + + :param last_known_trans_id: Target's last known transaction id. + :type last_known_trans_id: str + + :param insert_doc_cb: A callback for inserting received documents from + target. If not overriden, this will call u1db + insert_doc_from_target in synchronizer, which + implements the TAKE OTHER semantics. + :type insert_doc_cb: function + + :param ensure_callback: A callback that ensures we know the target + replica uid if the target replica was just + created. + :type ensure_callback: function + + :param defer_decryption: Whether to defer the decryption process using + the intermediate database. If False, + decryption will be done inline. + :type defer_decryption: bool + + :return: A deferred which fires with the new generation and + transaction id of the target replica. + :rtype: twisted.internet.defer.Deferred + """ + + self._ensure_callback = ensure_callback + + if sync_id is None: + sync_id = str(uuid4()) + self.source_replica_uid = source_replica_uid + + # save a reference to the callback so we can use it after decrypting + self._insert_doc_cb = insert_doc_cb + + gen_after_send, trans_id_after_send = yield self._send_docs( + docs_by_generation, + last_known_generation, + last_known_trans_id, + sync_id) + + cur_target_gen, cur_target_trans_id = yield self._receive_docs( + last_known_generation, last_known_trans_id, + ensure_callback, sync_id, + defer_decryption=defer_decryption) + + # update gen and trans id info in case we just sent and did not + # receive docs. + if gen_after_send is not None and gen_after_send > cur_target_gen: + cur_target_gen = gen_after_send + cur_target_trans_id = trans_id_after_send + + defer.returnValue([cur_target_gen, cur_target_trans_id]) + + +def _unauth_to_invalid_token_error(failure): + """ + An errback to translate unauthorized errors to our own invalid token + class. + + :param failure: The original failure. + :type failure: twisted.python.failure.Failure + + :return: Either the original failure or an invalid auth token error. + :rtype: twisted.python.failure.Failure + """ + failure.trap(Error) + if failure.getErrorMessage() == "401 Unauthorized": + raise InvalidAuthTokenError + return failure |