[refactor] make blobs backend write_blob() agnostic of twisted.web requests

3 files changed, 82 insertions, 36 deletions

diff --git a/src/leap/soledad/server/_blobs.py b/src/leap/soledad/server/_blobs.py
index 893f752e..86bbcdcb 100644
--- a/src/leap/soledad/server/_blobs.py
+++ b/src/leap/soledad/server/_blobs.py
@@ -65,6 +65,18 @@ class BlobNotFound(Exception):
     """
 
 
+class BlobExists(Exception):
+    """
+    Raised when a blob already exists in data storage backend.
+    """
+
+
+class QuotaExceeded(Exception):
+    """
+    Raised when the quota would be exceeded if an operation would be held.
+    """
+
+
 @implementer(interfaces.IBlobsBackend)
 class FilesystemBlobsBackend(object):
 
@@ -107,7 +119,7 @@ class FilesystemBlobsBackend(object):
             flags_file.write(raw_flags)
 
     @defer.inlineCallbacks
-    def write_blob(self, user, blob_id, request, namespace=''):
+    def write_blob(self, user, blob_id, fd, namespace=''):
         yield self.semaphore.acquire()
         path = self._get_path(user, blob_id, namespace)
         try:
@@ -115,18 +127,12 @@ class FilesystemBlobsBackend(object):
         except OSError as e:
             logger.warn("Got exception trying to create directory: %r" % e)
         if os.path.isfile(path):
-            # 409 - Conflict
-            request.setResponseCode(409)
-            request.write("Blob already exists: %s" % blob_id)
-            defer.returnValue(None)
+            raise BlobExists
         used = yield self.get_total_storage(user)
         if used > self.quota:
-            logger.error("Error 507: Quota exceeded for user: %s" % user)
-            request.setResponseCode(507)
-            request.write('Quota Exceeded!')
-            defer.returnValue(None)
+            raise QuotaExceeded
         logger.info('writing blob: %s - %s' % (user, blob_id))
-        fbp = FileBodyProducer(request.content)
+        fbp = FileBodyProducer(fd)
         with open(path, 'wb') as blobfile:
             yield fbp.startProducing(blobfile)
         yield self.semaphore.release()
@@ -304,8 +310,25 @@ class BlobsResource(resource.Resource):
     def render_PUT(self, request):
         logger.info("http put: %s" % request.path)
         user, blob_id, namespace = self._validate(request)
-        d = self._handler.write_blob(user, blob_id, request, namespace)
+
+        def catchBlobExists(failure):
+            failure.trap(BlobExists)
+            request.setResponseCode(409)
+            request.write("Blob already exists: %s" % blob_id)
+            request.finish()
+
+        def catchQuotaExceeded(failure):
+            failure.trap(QuotaExceeded)
+            logger.error("Error 507: Quota exceeded for user: %s" % user)
+            request.setResponseCode(507)
+            request.write('Quota Exceeded!')
+            request.finish()
+
+        fd = request.content
+        d = self._handler.write_blob(user, blob_id, fd, namespace=namespace)
         d.addCallback(lambda _: request.finish())
+        d.addErrback(catchBlobExists)
+        d.addErrback(catchQuotaExceeded)
         d.addErrback(self._error, request)
         return NOT_DONE_YET
 
diff --git a/src/leap/soledad/server/_incoming.py b/src/leap/soledad/server/_incoming.py
index be172b22..362039af 100644
--- a/src/leap/soledad/server/_incoming.py
+++ b/src/leap/soledad/server/_incoming.py
@@ -34,6 +34,8 @@ from leap.soledad.common.log import getLogger
 
 from leap.soledad.server._config import get_config
 from leap.soledad.server._blobs import BlobsServerState
+from leap.soledad.server._blobs import BlobExists
+from leap.soledad.server._blobs import QuotaExceeded
 
 
 __all__ = ['IncomingResource']
@@ -65,29 +67,49 @@ class IncomingResource(Resource):
         scheme = EncryptionSchemes.PUBKEY
         db = self.factory.open_database(uuid)
         if uses_legacy(db):
-            try:
-                doc = ServerDocument(doc_id)
-                content = request.content.read()
-                doc.content = self.formatter.format(content, scheme)
-                db.put_doc(doc)
-                self._finish(request)
-            except Exception as e:
-                self._error(e, request)
+            self._put_legacy(doc_id, scheme, db, 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='MX')
-            # FIXME: We really need to decouple request handling from the
-            # backend! This is very ugly, but will change when this refactor
-            # is done.
-            flags = [Flags.PENDING]
-            d.addCallback(lambda _: db.set_flags(uuid, doc_id, flags,
-                                                 namespace='MX'))
-            d.addCallback(lambda _: self._finish(request))
-            d.addErrback(self._error, request)
+            self._put_incoming(uuid, doc_id, scheme, db, request)
         return NOT_DONE_YET
 
+    def _put_legacy(self, doc_id, scheme, db, request):
+        try:
+            doc = ServerDocument(doc_id)
+            content = request.content.read()
+            doc.content = self.formatter.format(content, scheme)
+            db.put_doc(doc)
+            self._finish(request)
+        except Exception as e:
+            self._error(e, request)
+
+    def _put_incoming(self, user, blob_id, scheme, db, request):
+        raw_content = request.content.read()
+        preamble = self.formatter.preamble(raw_content, blob_id)
+        request.content = BytesIO(preamble + ' ' + raw_content)
+
+        def catchBlobExists(failure):
+            failure.trap(BlobExists)
+            request.setResponseCode(409)
+            request.write("Blob already exists: %s" % blob_id)
+            request.finish()
+
+        def catchQuotaExceeded(failure):
+            failure.trap(QuotaExceeded)
+            logger.error("Error 507: Quota exceeded for user: %s" % user)
+            request.setResponseCode(507)
+            request.write('Quota Exceeded!')
+            request.finish()
+
+        fd = request.content
+        d = db.write_blob(user, blob_id, fd, namespace='MX')
+        flags = [Flags.PENDING]
+        d.addCallback(lambda _: db.set_flags(user, blob_id, flags,
+                                             namespace='MX'))
+        d.addCallback(lambda _: request.finish())
+        d.addErrback(catchBlobExists)
+        d.addErrback(catchQuotaExceeded)
+        d.addErrback(self._error, request)
+
     def _finish(self, request):
         request.write('{"success": true}')
         request.finish()
diff --git a/src/leap/soledad/server/interfaces.py b/src/leap/soledad/server/interfaces.py
index a4dead70..11d75f11 100644
--- a/src/leap/soledad/server/interfaces.py
+++ b/src/leap/soledad/server/interfaces.py
@@ -45,22 +45,23 @@ class IBlobsBackend(Interface):
         :rtype: twisted.web.resource.Resource
         """
 
-    def write_blob(user, blob_id, request, namespace=''):
+    def write_blob(user, blob_id, fd, namespace=''):
         """
-        Write a blob to the backend storage after reading it from a request.
+        Write a blob to the backend storage.
 
         :param user: The id of the user who owns the blob.
         :type user: str
         :param blob_id: The id of the blob.
         :type blob_id: str
-        :param request: A representation of all of the information about the
-            request that is being made.
-        :type request: twisted.web.server.Request
+        :param fd: A file-like object into which the contents of the blob
+            should be written.
+        :type fd: file-like
         :param namespace: An optional namespace for the blob.
         :type namespace: str
 
         :return: A deferred that fires when the blob has been written to the
                  backend storage.
+        :rtype: twisted.internet.defer.Deferred
         """
 
     def delete_blob(user, blob_id, namespace=''):