Merge pull request #667 from tahoe-lafs/3265.reuse-storage-plugin-web-resource

reuse storage plugin web resource

src/allmydata/test/storage_plugin.py

@@ -16,6 +16,9 @@ from zope.interface import (
 from twisted.internet.defer import (
     succeed,
 )
+from twisted.web.resource import (
+    Resource,
+)
 from twisted.web.static import (
     Data,
 )
@@ -78,10 +81,26 @@ class DummyStorage(object):
             rendered, as an aid to testing.
         """
         items = configuration.items(self._client_section_name, [])
-        return Data(
+        resource = Data(
             dumps(dict(items)),
             b"text/json",
         )
+        # Give it some dynamic stuff too.
+        resource.putChild(b"counter", GetCounter())
+        return resource
+
+
+class GetCounter(Resource, object):
+    """
+    ``GetCounter`` is a resource that returns a count of the number of times
+    it has rendered a response to a GET request.
+
+    :ivar int value: The number of ``GET`` requests rendered so far.
+    """
+    value = 0
+    def render_GET(self, request):
+        self.value += 1
+        return dumps({"value": self.value})
 
 
 @implementer(RIDummy)

src/allmydata/test/test_storage_client.py

@@ -2,6 +2,7 @@ import hashlib
 from mock import Mock
 from json import (
     dumps,
+    loads,
 )
 from fixtures import (
     TempDir,
@@ -25,6 +26,10 @@ from zope.interface.verify import (
     verifyObject,
 )
 
+from hyperlink import (
+    URL,
+)
+
 from twisted.application.service import (
     Service,
 )
@@ -459,6 +464,32 @@ class StoragePluginWebPresence(AsyncTestCase):
         result = yield do_http(b"get", url)
         self.assertThat(result, Equals(dumps({b"web": b"1"})))
 
+    @inlineCallbacks
+    def test_plugin_resource_persistent_across_requests(self):
+        """
+        The plugin's resource is loaded and then saved and re-used for future
+        requests.
+        """
+        url = URL(
+            scheme=u"http",
+            host=u"127.0.0.1",
+            port=self.port,
+            path=(
+                u"storage-plugins",
+                self.storage_plugin.decode("utf-8"),
+                u"counter",
+            ),
+        ).to_text().encode("utf-8")
+        values = {
+            loads((yield do_http(b"get", url)))[u"value"],
+            loads((yield do_http(b"get", url)))[u"value"],
+        }
+        self.assertThat(
+            values,
+            # If the counter manages to go up then the state stuck around.
+            Equals({1, 2}),
+        )
+
 
 def make_broker(tub_maker=lambda h: Mock()):
     """

src/allmydata/web/storage_plugins.py

@@ -29,6 +29,8 @@ class StoragePlugins(Resource, object):
         """
         resources = self._client.get_client_storage_plugin_web_resources()
         try:
-            return resources[segment]
+            result = resources[segment]
         except KeyError:
-            return NoResource()
+            result = NoResource()
+        self.putChild(segment, result)
+        return result