OpenStack-Ansible mistral role¶

This role installs the following Systemd services:

mistral-api

mistral-engine

mistral-executor

mistral-notifier

To clone or view the source code for this repository, visit the role repository for os_mistral.

Default variables¶

# Installation method
mistral_install_method: "source"
mistral_venv_python_executable: "{{ openstack_venv_python_executable | default('python2') }}"

# Operating system user & groups
mistral_system_user_name: mistral
mistral_system_group_name: mistral
mistral_system_shell: /sbin/nologin
mistral_system_comment: Mistral Daemons
mistral_system_user_home: /var/lib/mistral

# Distribution deployment
mistral_package_state: latest

# 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
# by the py_pkgs lookup.
mistral_role_project_group: mistral_all

# Source package builds
mistral_git_repo: https://git.openstack.org/openstack/mistral
mistral_git_install_branch: master
mistral_upper_constraints_url: "{{ requirements_git_url | default('https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt?h=' ~ requirements_git_install_branch | default('master')) }}"
mistral_git_constraints:
  - "git+{{ mistral_git_repo }}@{{ mistral_git_install_branch }}#egg=mistral"
  - "--constraint {{ mistral_upper_constraints_url }}"
mistral_pip_packages:
  - mistral
  - PyMySQL
  - python-memcached
  - systemd-python

mistral_optional_oslomsg_amqp1_pip_packages:
  - oslo.messaging[amqp1]
mistral_venv_tag: "{{ venv_tag | default('untagged') }}"
mistral_bin: "{{ _mistral_bin }}"

mistral_pip_install_args: "{{ pip_install_options | default('') }}"

# Services
mistral_services:
  mistral-notifier:
    group: mistral_notifier
    service_name: mistral-notifier
    init_config_overrides: "{{ mistral_notifier_init_overrides }}"
    start_order: 1
    execstarts: "{{ _mistral_bin }}/mistral-server --server notifier"
  mistral-executor:
    group: mistral_executor
    service_name: mistral-executor
    init_config_overrides: "{{ mistral_executor_init_overrides }}"
    start_order: 1
    execstarts: "{{ _mistral_bin }}/mistral-server --server executor"
  mistral-engine:
    group: mistral_engine
    service_name: mistral-engine
    init_config_overrides: "{{ mistral_engine_init_overrides }}"
    start_order: 1
    execstarts: "{{ _mistral_bin }}/mistral-server --server engine"
  mistral-api:
    group: mistral_api
    service_name: mistral-api
    init_config_overrides: "{{ mistral_api_init_overrides }}"
    start_order: 2
    wsgi_app: true
    wsgi_name: mistral-wsgi-api
    uwsgi_overrides: "{{ mistral_api_uwsgi_ini_overrides }}"
    uwsgi_bind_address: "{{ mistral_bind_address }}"
    uwsgi_port: "{{ mistral_service_port }}"

# UWSGI settings
mistral_wsgi_processes_max: 16
mistral_wsgi_processes: "{{ [[ansible_processor_vcpus|default(1), 1] | max * 2, mistral_wsgi_processes_max] | min }}"
mistral_wsgi_threads: 1

# RPC
mistral_oslomsg_rpc_host_group: "{{ oslomsg_rpc_host_group | default('rabbitmq_all') }}"
mistral_oslomsg_rpc_setup_host: "{{ (mistral_oslomsg_rpc_host_group in groups) | ternary(groups[mistral_oslomsg_rpc_host_group][0], 'localhost') }}"
mistral_oslomsg_rpc_transport: "{{ oslomsg_rpc_transport | default('rabbit') }}"
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

# Notify
mistral_oslomsg_notify_host_group: "{{ oslomsg_notify_host_group | default('rabbitmq_all') }}"
mistral_oslomsg_notify_setup_host: "{{ (mistral_oslomsg_notify_host_group in groups) | ternary(groups[mistral_oslomsg_notify_host_group][0], 'localhost') }}"
mistral_oslomsg_notify_transport: "{{ oslomsg_notify_transport | default('rabbit') }}"
mistral_oslomsg_notify_servers: "{{ oslomsg_notify_servers | default('127.0.0.1') }}"
mistral_oslomsg_notify_port: "{{ oslomsg_notify_port | default('5672') }}"
mistral_oslomsg_notify_use_ssl: "{{ oslomsg_notify_use_ssl | default(False) }}"
mistral_oslomsg_notify_userid: "{{ mistral_oslomsg_rpc_userid }}"
mistral_oslomsg_notify_password: "{{ mistral_oslomsg_rpc_password }}"
mistral_oslomsg_notify_vhost: "{{ mistral_oslomsg_rpc_vhost }}"

# (Qdrouterd) integration
mistral_oslomsg_amqp1_enabled: "{{ mistral_oslomsg_rpc_transport == 'amqp' }}"

# Database
mistral_db_setup_host: "{{ ('galera_all' in groups) | ternary(groups['galera_all'][0], 'localhost') }}"
mistral_galera_address: "{{ galera_address | default('127.0.0.1') }}"
mistral_galera_database: mistral
mistral_galera_user: mistral

# Configuration options
mistral_debug: "{{ debug | default(false) }}"
mistral_bind_address: "{{ openstack_service_bind_address | default('0.0.0.0') }}"
mistral_service_port: 8989

# Overrides
mistral_notifier_init_overrides: {}
mistral_executor_init_overrides: {}
mistral_engine_init_overrides: {}
mistral_api_init_overrides: {}
mistral_api_uwsgi_ini_overrides: {}
mistral_mistral_conf_overrides: {}
mistral_policy_overrides: {}

# Service setup
mistral_service_setup_host: "{{ openstack_service_setup_host | default('localhost') }}"
mistral_service_setup_host_python_interpreter: "{{ openstack_service_setup_host_python_interpreter | default((mistral_service_setup_host == 'localhost') | ternary(ansible_playbook_python, ansible_python['executable'])) }}"
mistral_service_name: mistral
mistral_service_type: workflowv2
mistral_service_description: OpenStack Workflow service
mistral_service_in_ldap: false
mistral_service_user_domain_id: default
mistral_service_user_name: mistral
mistral_service_project_domain_id: default
mistral_service_project_name: service
mistral_role_name: admin
mistral_service_region: RegionOne
mistral_service_proto: http
mistral_service_publicuri_proto: "{{ openstack_service_publicuri_proto | default(mistral_service_proto) }}"
mistral_service_publicurl: "{{ mistral_service_publicuri_proto }}://{{ external_lb_vip_address }}:{{ mistral_service_port }}/v2"
mistral_service_internaluri_proto: "{{ openstack_service_internaluri_proto | default(mistral_service_proto) }}"
mistral_service_internalurl: "{{ mistral_service_internaluri_proto }}://{{ internal_lb_vip_address }}:{{ mistral_service_port }}/v2"
mistral_service_adminuri_proto: "{{ openstack_service_adminuri_proto | default(mistral_service_proto) }}"
mistral_service_adminurl: "{{ mistral_service_adminuri_proto }}://{{ internal_lb_vip_address }}:{{ mistral_service_port }}/v2"

# Specific pip packages provided by the user
mistral_user_pip_packages: []

Example playbook¶

---
- name: Install mistral server
  hosts: mistral_all
  user: root
  roles:
    - { role: "os_mistral", tags: [ "os-mistral" ] }

External Restart Hooks¶

When the role performs a restart of the service, it will notify an Ansible handler named Manage LB, which is a noop within this role. In the playbook, other roles may be loaded before and after this role which will implement Ansible handler listeners for Manage LB, allowing external roles to manage the load balancer endpoints responsible for sending traffic to the servers being restarted by marking them in maintenance or active mode, draining sessions, etc. For an example implementation, please reference the ansible-haproxy-endpoints role used by the openstack-ansible project.

Tags¶

This role supports two tags: mistral-install and mistral-config. The mistral-install tag can be used to install and upgrade. The mistral-config tag can be used to manage configuration.