Implement uWSGI for octavia-api

As part of the Pike goals we are moving api services to run as WSGI
apps. octavia-api service is set up as a wsgi app, and this patch
moves it over to uWSGI.

Since this is just a drop in replacement for the existing eventlet
service, operators an deployers should notice no difference.

Additionally, fix bug whereby git_install_branch was set to
"stable/ocata" for testing.

Change-Id: I0c473977e015015bd252a486c7191a95781b38a4
Implements: blueprint goal-deploy-api-in-wsgi

defaults/main.yml

@@ -166,6 +166,7 @@ octavia_pip_packages:
   - python-swiftclient
   - python-troveclient
   - octavia
+  - uwsgi
 
 octavia_api_init_overrides: {}
 octavia_worker_init_overrides: {}
@@ -178,6 +179,13 @@ octavia_services:
     group: octavia_api
     service_name: octavia-api
     init_config_overrides: "{{ octavia_api_init_overrides }}"
+    wsgi_overrides: "{{ octavia_api_uwsgi_ini_overrides }}"
+    wsgi_app: True
+    log_string: "--logto "
+    wsgi_name: octavia-wsgi
+    uwsgi_port: "{{ octavia_service_port }}"
+    uwsgi_bind_address: "{{ octavia_uwsgi_bind_address }}"
+    program_override: "{{ octavia_bin }}/uwsgi --ini /etc/uwsgi/octavia-api.ini"
   octavia-worker:
     group: octavia_worker
     service_name: octavia-worker
@@ -369,6 +377,14 @@ octavia_iptables_rules:
     reject_with: icmp6-port-unreachable
     ip_version: ipv6
 
+# uWSGI Settings
+octavia_wsgi_processes_max: 16
+octavia_wsgi_processes: "{{ [[ansible_processor_vcpus|default(1), 1] | max * 2, octavia_wsgi_processes_max] | min }}"
+octavia_wsgi_threads: 1
+octavia_wsgi_buffer_size: 65535
+octavia_uwsgi_bind_address: "0.0.0.0"
+octavia_api_uwsgi_ini_overrides: {}
+
 # Set up the drivers
 octavia_amphora_driver: amphora_haproxy_rest_driver
 octavia_compute_driver: compute_nova_driver

releasenotes/notes/octavia_uwsgi-f5d10fec3c1950bf.yaml

@@ -0,0 +1,15 @@
+---
+features:
+  - The ``octavia-api`` service has moved to run as a
+    uWSGI application. You can set the max number of
+    WSGI processes, the number of processes, threads,
+    and buffer size utilizing the
+    ``octavia_wsgi_processes_max``,
+    ``octavia_wsgi_processes``, ``octavia_wsgi_threads``,
+    and ``octavia_wsgi_buffer_size``.
+    Additionally, you can override any settings in the
+    uWSGI ini configuration file using the
+    ``octavia_api_uwsgi_ini_overrides`` setting.
+    The uWSGI application will listen on the address
+    specified by ``octavia_uwsgi_bind_address`` which
+    defaults to ``0.0.0.0``.

tasks/main.yml

@@ -40,6 +40,10 @@
   tags:
     - octavia-install
 
+- include: octavia_uwsgi.yml
+  tags:
+    - octavia-config
+
 - include: octavia_init_common.yml
   tags:
     - octavia-install

tasks/octavia_uwsgi.yml

@@ -0,0 +1,32 @@
+---
+# Copyright 2017, Rackspace US, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+- name: Ensure uWSGI directory exists
+  file:
+    path: "/etc/uwsgi/"
+    state: directory
+    mode: "0711"
+
+- name: Apply uWSGI configuration
+  config_template:
+    src: "octavia-uwsgi.ini.j2"
+    dest: "/etc/uwsgi/{{ item.value.service_name }}.ini"
+    mode: "0744"
+    config_overrides: "{{ item.value.wsgi_overrides }}"
+    config_type: ini
+  with_dict: "{{ octavia_services }}"
+  when: item.value.wsgi_app | default(False)
+  notify:
+    - Restart octavia services

templates/octavia-systemd-init.j2

@@ -10,10 +10,10 @@ Type=simple
 User={{ octavia_system_user_name }}
 Group={{ octavia_system_group_name }}
 
-{% if program_override is defined %}
+{% if item.value.program_override is defined %}
-ExecStart={{ program_override }} {{ program_config_options|default('') }} --log-file=/var/log/octavia/{{ item.value.service_name }}.log
+ExecStart={{ item.value.program_override }} {{ item.value.program_config_options|default('') }} {{ item.value.log_string | default('--log-file=') }}/var/log/octavia/{{ item.value.service_name }}.log
 {% else %}
-ExecStart={{ octavia_bin }}/{{ item.value.service_name }} {{ program_config_options|default('') }} --log-file=/var/log/octavia/{{ item.value.service_name }}.log
+ExecStart={{ octavia_bin }}/{{ item.value.service_name }} {{ item.value.program_config_options|default('') }} --log-file=/var/log/octavia/{{ item.value.service_name }}.log
 {% endif %}
 
 # Give a reasonable amount of time for the server to start up/shut down

templates/octavia-uwsgi.ini.j2

@@ -0,0 +1,19 @@
+[uwsgi]
+uid = {{ octavia_system_user_name }}
+gid = {{ octavia_system_group_name }}
+
+virtualenv = /openstack/venvs/octavia-{{ octavia_venv_tag }}
+wsgi-file = {{ octavia_bin }}/{{ item.value.wsgi_name }}
+http-socket = {{ item.value.uwsgi_bind_address }}:{{ item.value.uwsgi_port }}
+
+master = true
+enable-threads = true
+processes = {{ octavia_wsgi_processes }}
+threads = {{ octavia_wsgi_threads }}
+exit-on-reload = true
+die-on-term = true
+lazy-apps = true
+add-header = Connection: close
+buffer-size = {{ octavia_wsgi_buffer_size }}
+thunder-lock = true
+logfile-chmod = 644

tests/os_octavia-overrides.yml

@@ -86,8 +86,6 @@ octavia_package_state: latest
 octavia_neutron_management_network_name: lbaas-mgmt
 octavia_management_net_subnet_cidr: 10.1.7.0/24
 
-octavia_git_install_branch: stable/ocata
-
 octavia_ssh_enabled: True
 
 octavia_amphora_driver: "{% if test_octavia_amphora | bool %}amphora_haproxy_rest_driver{% else %}amphora_noop_driver{% endif %}"