Add quorum queues support for service

This change implements and enables by default quorum support
for rabbitmq as well as providing default variables to globally tune
it's behaviour.

In order to ensure upgrade path and ability to switch back to HA queues
we change vhost names with removing leading `/`, as enabling quorum
requires to remove exchange which is tricky thing to do with running
services.

Change-Id: I900f40d7db6c26356252a7be736c1b3bdc98cace

defaults/main.yml

@@ -105,7 +105,13 @@ mistral_oslomsg_rpc_servers: "{{ oslomsg_rpc_servers | default('127.0.0.1') }}"
 mistral_oslomsg_rpc_port: "{{ oslomsg_rpc_port | default('5672') }}"
 mistral_oslomsg_rpc_use_ssl: "{{ oslomsg_rpc_use_ssl | default(False) }}"
 mistral_oslomsg_rpc_userid: mistral
-mistral_oslomsg_rpc_vhost: /mistral
+# vhost name depends on value of oslomsg_rabbit_quorum_queues. In case quorum queues
+# are not used - vhost name will be prefixed with leading `/`.
+mistral_oslomsg_rpc_vhost:
+  - name: /mistral
+    state: "{{ mistral_oslomsg_rabbit_quorum_queues | ternary('absent', 'present') }}"
+  - name: mistral
+    state: "{{ mistral_oslomsg_rabbit_quorum_queues | ternary('present', 'absent') }}"
 mistral_oslomsg_rpc_ssl_version: "{{ oslomsg_rpc_ssl_version | default('TLSv1_2') }}"
 mistral_oslomsg_rpc_ssl_ca_file: "{{ oslomsg_rpc_ssl_ca_file | default('') }}"
 
@@ -122,6 +128,11 @@ mistral_oslomsg_notify_vhost: "{{ mistral_oslomsg_rpc_vhost }}"
 mistral_oslomsg_notify_ssl_version: "{{ oslomsg_notify_ssl_version | default('TLSv1_2') }}"
 mistral_oslomsg_notify_ssl_ca_file: "{{ oslomsg_notify_ssl_ca_file | default('') }}"
 
+## RabbitMQ integration
+mistral_oslomsg_rabbit_quorum_queues: "{{ oslomsg_rabbit_quorum_queues | default(True) }}"
+mistral_oslomsg_rabbit_quorum_delivery_limit: "{{ oslomsg_rabbit_quorum_delivery_limit | default(0) }}"
+mistral_oslomsg_rabbit_quorum_max_memory_bytes: "{{ oslomsg_rabbit_quorum_max_memory_bytes | default(0) }}"
+
 # (Qdrouterd) integration
 mistral_oslomsg_amqp1_enabled: "{{ mistral_oslomsg_rpc_transport == 'amqp' }}"
 

templates/mistral.conf.j2

@@ -3,7 +3,7 @@
 [DEFAULT]
 debug = {{ mistral_debug }}
 use_journal = True
-transport_url = {{ mistral_oslomsg_rpc_transport }}://{% for host in mistral_oslomsg_rpc_servers.split(',') %}{{ mistral_oslomsg_rpc_userid }}:{{ mistral_oslomsg_rpc_password }}@{{ host }}:{{ mistral_oslomsg_rpc_port }}{% if not loop.last %},{% else %}/{{ mistral_oslomsg_rpc_vhost }}{% if mistral_oslomsg_rpc_use_ssl | bool %}?ssl=1&ssl_version={{ mistral_oslomsg_rpc_ssl_version }}&ssl_ca_file={{ mistral_oslomsg_rpc_ssl_ca_file }}{% else %}?ssl=0{% endif %}{% endif %}{% endfor %}
+transport_url = {{ mistral_oslomsg_rpc_transport }}://{% for host in mistral_oslomsg_rpc_servers.split(',') %}{{ mistral_oslomsg_rpc_userid }}:{{ mistral_oslomsg_rpc_password }}@{{ host }}:{{ mistral_oslomsg_rpc_port }}{% if not loop.last %},{% else %}/{{ _mistral_oslomsg_rpc_vhost_conf }}{% if mistral_oslomsg_rpc_use_ssl | bool %}?ssl=1&ssl_version={{ mistral_oslomsg_rpc_ssl_version }}&ssl_ca_file={{ mistral_oslomsg_rpc_ssl_ca_file }}{% else %}?ssl=0{% endif %}{% endif %}{% endfor %}
 
 [api]
 host = {{ mistral_bind_address }}
@@ -38,3 +38,9 @@ service_type = {{ mistral_service_type }}
 memcached_servers = {{ mistral_memcached_servers }}
 memcache_security_strategy = ENCRYPT
 memcache_secret_key = {{ memcached_encryption_key }}
+
+[oslo_messaging_rabbit]
+ssl = {{ mistral_oslomsg_notify_use_ssl | bool }}
+rabbit_quorum_queue = {{ mistral_oslomsg_rabbit_quorum_queues }}
+rabbit_quorum_delivery_limit = {{ mistral_oslomsg_rabbit_quorum_delivery_limit }}
+rabbit_quorum_max_memory_bytes = {{ mistral_oslomsg_rabbit_quorum_max_memory_bytes }}

vars/main.yml

@@ -18,6 +18,11 @@ _mistral_is_first_play_host: >-
     (mistral_services['mistral-api']['group'] in group_names and
       inventory_hostname == (groups[mistral_services['mistral-api']['group']] | intersect(ansible_play_hosts)) | first) | bool
   }}
+_mistral_oslomsg_rpc_vhost_conf: >-
+  {{
+    (mistral_oslomsg_rpc_vhost is string) | ternary(
+      mistral_oslomsg_rpc_vhost, mistral_oslomsg_rpc_vhost | selectattr('state', 'eq', 'present') | map(attribute='name') | first)
+  }}
 
 #
 # Compile a list of the services on a host based on whether