[feature] add blobs as a incoming api backend

We started with CouchDB due legacy system relying on it. This commit
adds the possibility of adding blobs as a IncomingAPI backend if blobs
is enabled on config file.

-- Resolves: #8868

2 files changed, 58 insertions, 7 deletions

diff --git a/src/leap/soledad/server/_blobs.py b/src/leap/soledad/server/_blobs.py
index f87c3818..87b171fb 100644
--- a/src/leap/soledad/server/_blobs.py
+++ b/src/leap/soledad/server/_blobs.py
@@ -237,3 +237,23 @@ if __name__ == '__main__':
     factory = Site(root)
     reactor.listenTCP(args.port, factory)
     reactor.run()
+
+
+class BlobsServerState(object):
+    """
+    Given a backend name, it gives a instance of IBlobsBackend
+    """
+    # Allowed backend classes are defined here
+    handlers = {"filesystem": FilesystemBlobsBackend}
+
+    def __init__(self, backend, **backend_kwargs):
+        if backend not in self.handlers:
+            raise ImproperlyConfiguredException("No such backend: %s", backend)
+        self.backend = self.handlers[backend](**backend_kwargs)
+
+    def open_database(self, user_id):
+        """
+        That method is just for compatibility with CouchServerState, so
+        IncomingAPI can change backends.
+        """
+        return self.backend
diff --git a/src/leap/soledad/server/_incoming.py b/src/leap/soledad/server/_incoming.py
index 6fd91a08..6fdeb7ae 100644
--- a/src/leap/soledad/server/_incoming.py
+++ b/src/leap/soledad/server/_incoming.py
@@ -17,38 +17,61 @@
 """
 A twisted resource that saves externally delivered documents into user's db.
 """
+from twisted.web.server import NOT_DONE_YET
 from twisted.web.resource import Resource
 from ._config import get_config
+from io import BytesIO
+from leap.soledad.server._blobs import BlobsServerState
 from leap.soledad.common.couch.state import CouchServerState
 from leap.soledad.common.document import ServerDocument
 from leap.soledad.common.crypto import ENC_JSON_KEY
 from leap.soledad.common.crypto import ENC_SCHEME_KEY
 from leap.soledad.common.crypto import EncryptionSchemes
+from leap.soledad.common import preamble
 
 
 __all__ = ['IncomingResource']
 
 
-def _default_backend():
+def _get_backend_from_config():
     conf = get_config()
-    return CouchServerState(conf['couch_url'], create_cmd=conf['create_cmd'])
+    if conf['blobs']:
+        return BlobsServerState("filesystem", conf['blobs_path'])
+    return CouchServerState(conf['couch_url'])
 
 
 class IncomingResource(Resource):
     isLeaf = True
 
     def __init__(self, backend_factory=None):
-        self.factory = backend_factory or _default_backend()
+        self.factory = backend_factory or _get_backend_from_config()
         self.formatter = IncomingFormatter()
 
     def render_PUT(self, request):
         uuid, doc_id = request.postpath
         scheme = EncryptionSchemes.PUBKEY
         db = self.factory.open_database(uuid)
-        doc = ServerDocument(doc_id)
-        doc.content = self.formatter.format(request.content.read(), scheme)
-        db.put_doc(doc)
-        return '{"success": true}'
+        if hasattr(db, 'put_doc'):
+            doc = ServerDocument(doc_id)
+            doc.content = self.formatter.format(request.content.read(), scheme)
+            db.put_doc(doc)
+            self._finish(request)
+        else:
+            raw_content = request.content.read()
+            preamble = self.formatter.preamble(raw_content, doc_id)
+            request.content = BytesIO(preamble + raw_content)
+            d = db.write_blob(uuid, doc_id, request, namespace='incoming')
+            d.addCallback(lambda _: self._finish(request))
+        return NOT_DONE_YET
+
+    def _finish(self, request):
+        request.write('{"success": true}')
+        request.finish()
+
+    def _error(self, e, request):
+        request.write('{"success": false}')
+        request.setResponseCode(500)
+        request.finish()
 
 
 class IncomingFormatter(object):
@@ -65,3 +88,11 @@ class IncomingFormatter(object):
                 self.ERROR_DECRYPTING_KEY: False,
                 ENC_SCHEME_KEY: EncryptionSchemes.NONE,
                 ENC_JSON_KEY: raw_content}
+
+    def preamble(self, raw_content, doc_id):
+        rev = '0'
+        scheme = preamble.ENC_SCHEME.external
+        method = preamble.ENC_METHOD.pgp
+        size = len(raw_content)
+        return preamble.Preamble(doc_id, rev, scheme, method,
+                                 content_size=size).encode()