Implement uWSGI for glance-api

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

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

Implements: blueprint goal-deploy-api-in-wsgi
Change-Id: Ie5fbf437031be01682534c466b3737d090a81c57

defaults/main.yml

@@ -218,6 +218,7 @@ glance_pip_packages:
   - python-keystoneclient
   - python-memcached
   - python-swiftclient
+  - uwsgi
   - warlock
 
 glance_api_init_overrides: {}
@@ -230,12 +231,25 @@ glance_services:
     service_name: glance-api
     init_config_overrides: "{{ glance_api_init_overrides }}"
     start_order: 1
+    wsgi_overrides: "{{ glance_api_uwsgi_ini_overrides }}"
+    wsgi_app: True
+    log_string: "--logto "
+    wsgi_name: glance-wsgi-api
+    uwsgi_bind_address: "{{glance_api_bind_address }}"
+    uwsgi_port: "{{ glance_api_service_port }}"
+    program_override: "{{ glance_bin }}/uwsgi --ini /etc/uwsgi/glance-api.ini"
   glance-registry:
     group: glance_registry
     service_name: glance-registry
     init_config_overrides: "{{ glance_registry_init_overrides }}"
     start_order: 2
 
+# Glance uWSGI settings
+glance_wsgi_processes_max: 16
+glance_wsgi_processes: "{{ [[ansible_processor_vcpus|default(1), 1] | max * 2, glance_wsgi_processes_max] | min }}"
+glance_wsgi_threads: 1
+glance_wsgi_buffer_size: 65535
+
 # This variable is used by the repo_build process to determine
 # which host group to check for members of before building the
 # pip packages required by this role. The value is picked up
@@ -253,3 +267,4 @@ glance_glance_scrubber_conf_overrides: {}
 glance_glance_scheme_json_overrides: {}
 glance_glance_swift_store_conf_overrides: {}
 glance_policy_overrides: {}
+glance_api_uwsgi_ini_overrides: {}

releasenotes/notes/glance_uwsgi-dd5fe62e6f85ecd2.yaml

@@ -0,0 +1,12 @@
+---
+features:
+  - The ``glance-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
+    ``glance_wsgi_processes_max``,
+    ``glance_wsgi_processes``, ``glance_wsgi_threads``,
+    and ``glance_wsgi_buffer_size``.
+    Additionally, you can override any settings in the
+    uWSGI ini configuration file using the
+    ``glance_api_uwsgi_ini_overrides`` setting.

tasks/glance_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: "glance-uwsgi.ini.j2"
+    dest: "/etc/uwsgi/{{ item.service_name }}.ini"
+    mode: "0744"
+    config_overrides: "{{ item.wsgi_overrides }}"
+    config_type: ini
+  with_items: "{{ filtered_glance_services }}"
+  when: item.wsgi_app | default(False)
+  notify:
+    - Restart glance services

tasks/main.yml

@@ -49,6 +49,10 @@
   tags:
     - glance-config
 
+- include: glance_uwsgi.yml
+  tags:
+    - glance-config
+
 - include: glance_service_setup.yml
   static: no
   when:

templates/glance-systemd-init.j2

@@ -11,9 +11,9 @@ User={{ glance_system_user_name }}
 Group={{ glance_system_group_name }}
 
 {% if program_override is defined %}
-ExecStart={{ program_override }} {{ program_config_options | default('') }} --log-file=/var/log/glance/{{ item.service_name }}.log
+ExecStart={{ item.program_override }} {{ item.program_config_options | default('') }} {{ item.log_string | default('--log-file=') }}/var/log/glance/{{ item.service_name }}.log
 {% else %}
-ExecStart={{ glance_bin }}/{{ item.service_name }} {{ program_config_options | default('') }} --log-file=/var/log/glance/{{ item.service_name }}.log
+ExecStart={{ glance_bin }}/{{ item.service_name }} {{ item.program_config_options | default('') }} --log-file=/var/log/glance/{{ item.service_name }}.log
 {% endif %}
 
 # Give a reasonable amount of time for the server to start up/shut down

templates/glance-uwsgi.ini.j2

@@ -0,0 +1,19 @@
+[uwsgi]
+uid = {{ glance_system_user_name }}
+gid = {{ glance_system_group_name }}
+
+virtualenv = /openstack/venvs/glance-{{ glance_venv_tag }}
+wsgi-file = {{ glance_bin }}/{{ item.wsgi_name }}
+http-socket = {{ item.uwsgi_bind_address }}:{{ item.uwsgi_port }}
+
+master = true
+enable-threads = true
+processes = {{ glance_wsgi_processes }}
+threads = {{ glance_wsgi_threads }}
+exit-on-reload = true
+die-on-term = true
+lazy-apps = true
+add-header = Connection: close
+buffer-size = {{ glance_wsgi_buffer_size }}
+thunder-lock = true
+logfile-chmod = 644