Process HEAD API requests to return property metadata

4 files changed, 83 insertions, 2 deletions

diff --git a/sugar_network/db/commands.py b/sugar_network/db/commands.py
index 07a733b..5cee8c3 100644
--- a/sugar_network/db/commands.py
+++ b/sugar_network/db/commands.py
@@ -203,6 +203,9 @@ class Response(dict):
         args = ['%s=%r' % i for i in self.items()]
         return '<Response %s>' % ' '.join(args)
 
+    def __contains__(self, key):
+        dict.__contains__(self, key.lower())
+
     def __getitem__(self, key):
         return self.get(key.lower())
 
diff --git a/sugar_network/db/router.py b/sugar_network/db/router.py
index e3e56eb..19eab12 100644
--- a/sugar_network/db/router.py
+++ b/sugar_network/db/router.py
@@ -184,7 +184,8 @@ class Router(object):
         elif not result_streamed:
             if response.content_type == 'application/json':
                 result = json.dumps(result)
-            response.content_length = len(result) if result else 0
+            if 'content-length' not in response:
+                response.content_length = len(result) if result else 0
 
         _logger.trace('Called %s: response=%r result=%r streamed=%r',
                 request_repr, response, result, result_streamed)
diff --git a/sugar_network/db/volume.py b/sugar_network/db/volume.py
index 1408a83..7b28b75 100644
--- a/sugar_network/db/volume.py
+++ b/sugar_network/db/volume.py
@@ -17,6 +17,7 @@ import os
 import re
 import sys
 import time
+import json
 import hashlib
 import logging
 from contextlib import contextmanager
@@ -201,7 +202,7 @@ class VolumeCommands(CommandsProcessor):
         return self._get_props(doc, request, reply)
 
     @property_command(method='GET', mime_type='application/json')
-    def get_prop(self, document, guid, prop, request, response, part=None):
+    def get_prop(self, document, guid, prop, request, response):
         directory = self.volume[document]
         prop = directory.metadata[prop]
         doc = directory.get(guid)
@@ -221,6 +222,29 @@ class VolumeCommands(CommandsProcessor):
                     http.NotFound, 'BLOB does not exist')
             return meta
 
+    @property_command(method='HEAD')
+    def get_prop_meta(self, document, guid, prop, request, response):
+        directory = self.volume[document]
+        prop = directory.metadata[prop]
+        doc = directory.get(guid)
+        doc.request = request
+
+        prop.assert_access(env.ACCESS_READ)
+
+        if isinstance(prop, StoredProperty):
+            meta = doc.meta(prop.name)
+            value = meta.pop('value')
+            response.content_length = len(json.dumps(value))
+        else:
+            meta = prop.on_get(doc, doc.meta(prop.name))
+            enforce(meta is not None and ('blob' in meta or 'url' in meta),
+                    http.NotFound, 'BLOB does not exist')
+            if 'blob' in meta:
+                meta.pop('blob')
+                meta['url'] = '/'.join([request.static_prefix] + request.path)
+            response.content_length = meta['blob_size']
+        response['SN-property'] = json.dumps(meta)
+
     def on_create(self, request, props, event):
         if 'guid' in props:
             # TODO Temporal security hole, see TODO
diff --git a/tests/units/db/volume.py b/tests/units/db/volume.py
index 70f3adf..6af78ee 100755
--- a/tests/units/db/volume.py
+++ b/tests/units/db/volume.py
@@ -4,6 +4,7 @@
 import os
 import sys
 import time
+import json
 import shutil
 import hashlib
 from cStringIO import StringIO
@@ -1131,6 +1132,58 @@ class VolumeTest(tests.Test):
         guid = self.call('POST', document='testdocument', content={'prop2': 'value2'})
         self.assertEqual('value2', self.call('GET', document='testdocument', guid=guid, prop='prop1'))
 
+    def test_prop_meta(self):
+
+        class TestDocument(db.Document):
+
+            @db.indexed_property(slot=1, default='')
+            def prop(self, value):
+                return value
+
+            @db.blob_property()
+            def blob1(self, value):
+                return value
+
+            @db.blob_property()
+            def blob2(self, value):
+                return value
+
+            @blob2.setter
+            def blob2(self, value):
+                return {'url': 'http://new', 'foo': 'bar', 'blob_size': 100}
+
+        volume = db.Volume(tests.tmpdir, [TestDocument])
+        cp = VolumeCommands(volume)
+
+        request = db.Request(method='POST', document='testdocument')
+        request.content = {'prop': 'prop', 'blob1': 'blob', 'blob2': ''}
+        guid = cp.call(request, db.Response())
+
+        request = db.Request(method='HEAD', document='testdocument', guid=guid, prop='prop')
+        response = db.Response()
+        assert cp.call(request, response) is None
+        meta = volume['testdocument'].get(guid).meta('prop')
+        meta.pop('value')
+        self.assertEqual(meta, json.loads(response['SN-property']))
+
+        request = db.Request(method='HEAD', document='testdocument', guid=guid, prop='blob1')
+        request.static_prefix = 'http://localhost'
+        request.path = ['path']
+        response = db.Response()
+        assert cp.call(request, response) is None
+        meta = volume['testdocument'].get(guid).meta('blob1')
+        meta.pop('blob')
+        meta['url'] = 'http://localhost/path'
+        self.assertEqual(meta, json.loads(response['SN-property']))
+        self.assertEqual(len('blob'), response.content_length)
+
+        request = db.Request(method='HEAD', document='testdocument', guid=guid, prop='blob2')
+        response = db.Response()
+        assert cp.call(request, response) is None
+        meta = volume['testdocument'].get(guid).meta('blob2')
+        self.assertEqual(meta, json.loads(response['SN-property']))
+        self.assertEqual(100, response.content_length)
+
     def call(self, method, document=None, guid=None, prop=None,
             accept_language=None, content=None, content_stream=None,
             content_type=None, if_modified_since=None, static_prefix=None,