Update to get things working with kubernetes

This is mostly for the sake of learning: the fact that the sqlite
database is in container means it's fairly useless: you can't scale
horizontally. Future work will explore different ways of dealing
what that.

The Dockerfile is update to reflect the latest placement extraction
changes and to put config in the container rather than using a
shared volume.

The placement-uwsgi.ini is update so it runs http directly.
There's no need for an nginx or apache setup, a k8s LoadBalancer
in deployment.yaml takes care of that.

The uwsgi ini is based on info at:
nginx/kubernetes-ingress#143 (comment)

Using minikube the steps are:

    eval $(minikube docker-env)
    docker build -t placedock:1.0 .
    kubectl apply -f deployment.yaml
    kubectl expose deployment placement-deployment --type=LoadBalancer
    minikube service placement-deployment --url

Dockerfile

@@ -20,26 +20,27 @@ RUN pip3 install -r placement-requirements.txt
 
 # Do this all in one big piece otherwise the nova bits are out of date
 # Thanks to ingy for figuring out a faster way to do this.
+# We must get rid of a symlink which can lead to errors, see:
+# https://github.com/python/cpython/pull/4267
 RUN git clone --depth=1 https://git.openstack.org/openstack/nova && \
     cd nova && \
     git fetch --depth=2 --append origin \
-        refs/changes/62/549862/11 \
-        refs/changes/66/362766/75 \
-        refs/changes/35/541435/17 \
+        refs/changes/62/549862/14 \
+        refs/changes/66/362766/79 \
+        refs/changes/35/541435/21 \
+        refs/changes/57/553857/2 \
         refs/changes/62/543262/7 && \
     git cherry-pick $(cut -f1 .git/FETCH_HEAD) && \
-    # get rid of a symlink which can lead to errors, see:
-    # https://github.com/python/cpython/pull/4267
     find . -type l -exec rm {} \; && \
     pip3 install --no-deps .
 
 
-
 # create the placement db
 ADD sync.py /
-ADD /shared/etc/nova/nova.conf /
-RUN python3 sync.py --config-file nova.conf
+ADD /shared/placement-uwsgi.ini /
+RUN mkdir /etc/nova
+ADD /shared/etc/nova/nova.conf /etc/nova
+RUN python3 sync.py --config-file /etc/nova/nova.conf
 
-# Mount nova config and uwsgi config
-VOLUME /shared
-ENTRYPOINT ["uwsgi", "--ini", "/shared/placement-uwsgi.ini"]
+CMD ["/usr/sbin/uwsgi", "--ini", "/placement-uwsgi.ini"]
+EXPOSE 80

deployment.yaml

@@ -0,0 +1,19 @@
+apiVersion: apps/v1  # for versions before 1.9.0 use apps/v1beta2
+kind: Deployment
+metadata:
+    name: placement-deployment
+spec:
+    selector:
+        matchLabels:
+            app: placement
+    replicas: 1
+    template:
+        metadata:
+            labels:
+                app: placement
+        spec:
+            containers:
+                - name: placement
+                  image: placedock:1.0
+                  ports:
+                  - containerPort: 80

shared/placement-uwsgi.ini

@@ -1,18 +1,43 @@
-
 [uwsgi]
-chmod-socket = 666
-socket = 172.*:80
-lazy-apps = true
-add-header = Connection: close
-buffer-size = 65535
-hook-master-start = unix_signal:15 gracefully_kill_them_all
-thunder-lock = true
 plugins = python3
-enable-threads = true
-worker-reload-mercy = 90
-exit-on-reload = false
-die-on-term = true
-master = true
-processes = 4
 wsgi-file = /usr/bin/nova-placement-api
-env = OS_PLACEMENT_CONFIG_DIR=/shared/etc/nova
+
+processes = 2
+threads = 10
+
+http-socket = :80
+http-enable-proxy-protocol = 1
+http-auto-chunked = true
+http-keepalive = 75
+http-timeout = 75
+stats = :1717
+stats-http = 1
+offload-threads = 10
+
+# Better startup/shutdown in docker:
+die-on-term = 1
+lazy-apps = 0
+
+vacuum = 1
+master = 1
+enable-threads = true
+thunder-lock = 1
+buffer-size = 65535
+
+# Logging
+log-x-forwarded-for = true
+
+# Avoid errors on aborted client connections
+ignore-sigpipe = true
+ignore-write-errors = true
+disable-write-exception = true
+
+no-defer-accept = 1
+
+# Limits, Kill requests after 120 seconds
+harakiri = 120
+harakiri-verbose = true
+post-buffering = 4096
+
+# Custom headers
+add-header = Connection: Keep-Alive