Add mistral-event-engine image

Mistral now has an event engine for triggering cron-like events.

Change-Id: I039e812113c7ad565e11af6045cb3bd1a7af706b

docker/mistral/mistral-event-engine/Dockerfile.j2

@@ -0,0 +1,22 @@
+FROM {{ namespace }}/{{ image_prefix }}mistral-base:{{ tag }}
+LABEL maintainer="{{ maintainer }}" name="{{ image_name }}" build-date="{{ build_date }}"
+
+{% block mistral_event_engine_header %}{% endblock %}
+
+{% import "macros.j2" as macros with context %}
+
+{% if install_type == 'binary' %}
+    {% if base_distro in ['centos', 'oraclelinux', 'rhel'] %}
+        {% set mistral_event_engine_packages = ['openstack-mistral-event-engine'] %}
+        {{ macros.install_packages(mistral_event_engine_packages | customizable("packages")) }}
+    {% elif base_distro in ['debian', 'ubuntu'] %}
+RUN echo '{{ install_type }} not yet available for {{ base_distro }}' \
+    && /bin/false
+    {% endif %}
+
+{% endif %}
+
+{% block mistral_event_engine_footer %}{% endblock %}
+{% block footer %}{% endblock %}
+
+USER mistral

releasenotes/notes/add-mistral-event-engine-053ebdfbd50e2e65.yaml

@@ -0,0 +1,3 @@
+---
+features:
+  - Add mistral-event-engine image.

tests/test_build.py

@@ -121,6 +121,7 @@ class BuildTestUbuntuBinary(BuildTest, base.BaseTestCase):
         "heat-all",
         "karbor-base",
         "kuryr-base",
+        "mistral-event-engine",
         "monasca-base",
         "neutron-sfc-agent",
         "octavia-base",
@@ -163,6 +164,7 @@ class BuildTestDebianBinary(BuildTest, base.BaseTestCase):
         "heat-all",
         "karbor-base",
         "kuryr-base",
+        "mistral-event-engine",
         "monasca-base",
         "neutron-sfc-agent",
         "octavia-base",