Get rid of code patching in containers

When generating CNI container our scripts were applying two patches to
the Kuryr codebase. One was making sure k8s_client will correctly split
WATCH responses with b"\n" and second was patching cni.main to enable
daemonized mode for os_vif's privsep instead of sudo/rootwrap mode.

This was critically unmaintainable, as any changes to patched files might
make the patches unapplyable and break the container building scripts.

This commit resolves the problem by completely removing step of applying
patches:
* k8s_client patch is applied directly into the codbase as it's a no-op
  in Python 2.7 and in Python 3.5 should be a correct way of doing
  things.
* cni.main patch gets removed completely, as CNI container is run with
  sudo privileges, so privsep in rootwrap/sudo mode will work fine (and
  maybe even better as it gets rid of "broken pipe" errors in kubelet
  logs).

Change-Id: I4171e3807dece12e41e04abefa1d16eb675f7d06

cni_builder.Dockerfile

@@ -3,7 +3,6 @@ LABEL authors="Antoni Segura Puimedon<toni@kuryr.org>, Vikas Choudhary<vichoudh@
 
 RUN yum install --setopt=tsflags=nodocs --assumeyes \
         net-tools \
-        patch \
         gcc \
         python-devel \
         wget \
@@ -28,8 +27,6 @@ COPY . /opt/kuryr-kubernetes
 
 # Installing from dev because of this issue, https://github.com/pyinstaller/pyinstaller/issues/2434
 RUN cd /opt/kuryr-kubernetes \
-    && patch -b kuryr_kubernetes/k8s_client.py < k8s_client.patch \
-    && patch -b kuryr_kubernetes/cni/main.py < cni_main.patch \
     && pip3.5 install --no-cache-dir . \
     && pip3.5 install git+https://github.com/pyinstaller/pyinstaller.git \
     && pip3.5 install pyroute2 \

cni_main.patch

@@ -1,12 +0,0 @@
---- /root/tmp/kuryr-kubernetes/kuryr_kubernetes/cni/main.py	2017-06-19 07:15:39.898398766 -0400
-+++ kuryr_kubernetes/cni/main.py	2017-06-22 04:28:41.421123949 -0400
-@@ -61,6 +61,9 @@
-         config.init(args)
-         config.setup_logging()
-         os_vif.initialize()
-+        ovs = os_vif._EXT_MANAGER['ovs'].obj
-+        ovs_mod = sys.modules[ovs.__module__]
-+        ovs_mod.linux_net.privsep.vif_plug.start(ovs_mod.linux_net.privsep.priv_context.Method.FORK)
-         clients.setup_kubernetes_client()
-         self._pipeline = h_cni.CNIPipeline()
-         self._watcher = k_watcher.Watcher(self._pipeline)

k8s_client.patch

@@ -1,11 +0,0 @@
---- /root/tmp/kuryr-kubernetes/kuryr_kubernetes/k8s_client.py	2017-06-19 07:15:39.901398831 -0400
-+++ kuryr_kubernetes/k8s_client.py	2017-06-22 06:14:48.177325667 -0400
-@@ -138,7 +138,7 @@
-                                  headers=header)) as response:
-                 if not response.ok:
-                     raise exc.K8sClientException(response.text)
--                for line in response.iter_lines(delimiter='\n'):
-+                for line in response.iter_lines(delimiter=b'\n'):
-                     line = line.strip()
-                     if line:
-                         yield jsonutils.loads(line)

kuryr_kubernetes/k8s_client.py

@@ -162,7 +162,7 @@ class K8sClient(object):
                                  headers=header)) as response:
                 if not response.ok:
                     raise exc.K8sClientException(response.text)
-                for line in response.iter_lines(delimiter='\n'):
+                for line in response.iter_lines(delimiter=b'\n'):
                     line = line.strip()
                     if line:
                         yield jsonutils.loads(line)