1 files changed, 135 insertions, 0 deletions
diff --git a/u1db/remote/http_target.py b/u1db/remote/http_target.py
new file mode 100644
index 00000000..1028963e
--- /dev/null
+++ b/u1db/remote/http_target.py
@@ -0,0 +1,135 @@
+# Copyright 2011-2012 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/>.
+
+"""SyncTarget API implementation to a remote HTTP server."""
+
+try:
+    import simplejson as json
+except ImportError:
+    import json  # noqa
+
+from u1db import (
+    Document,
+    SyncTarget,
+    )
+from u1db.errors import (
+    BrokenSyncStream,
+    )
+from u1db.remote import (
+    http_client,
+    utils,
+    )
+
+
+class HTTPSyncTarget(http_client.HTTPClientBase, SyncTarget):
+    """Implement the SyncTarget api to a remote HTTP server."""
+
+    @staticmethod
+    def connect(url):
+        return HTTPSyncTarget(url)
+
+    def get_sync_info(self, source_replica_uid):
+        self._ensure_connection()
+        res, _ = self._request_json('GET', ['sync-from', source_replica_uid])
+        return (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_transaction_id):
+        self._ensure_connection()
+        if self._trace_hook:  # for tests
+            self._trace_hook('record_sync_info')
+        self._request_json('PUT', ['sync-from', source_replica_uid], {},
+                              {'generation': source_replica_generation,
+                               'transaction_id': source_transaction_id})
+
+    def _parse_sync_stream(self, data, return_doc_cb, ensure_callback=None):
+        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 = Document(entry['id'], entry['rev'], 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):
+        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_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']
+
+    # for tests
+    _trace_hook = None
+
+    def _set_trace_hook_shallow(self, cb):
+        self._trace_hook = cb