Add wsgi module

The wsgi_script feature is being removed because of some changes in
underlying python packaging tooling. This makes heat to vendor the wsgi
module which can be used instead of the wsgi script, according to
the proposed community goal[1]. The existing wsgi scripts are kept now
for smooth transition.

[1] https://review.opendev.org/c/openstack/governance/+/902807

Depends-On: https://review.opendev.org/c/openstack/devstack/+/902758
Change-Id: I4dc92f06610753171215913180ce7cdab15ba047

devstack/lib/heat

@@ -39,7 +39,7 @@ GITBRANCH["python-heatclient"]=${HEATCLIENT_BRANCH:-master}
 HEAT_USE_APACHE=${HEAT_USE_APACHE:-${HEAT_USE_MOD_WSGI:-True}}
 
 HEAT_DIR=$DEST/heat
-HEAT_FILES_DIR=$HEAT_DIR/heat/httpd/files
+HEAT_HTTPD_VHOST_FILES_DIR=$HEAT_DIR/etc/heat/httpd
 
 HEAT_STANDALONE=$(trueorfalse False HEAT_STANDALONE)
 HEAT_ENABLE_ADOPT_ABANDON=$(trueorfalse False HEAT_ENABLE_ADOPT_ABANDON)
@@ -58,8 +58,8 @@ HEAT_TRUSTEE_DOMAIN=${HEAT_TRUSTEE_DOMAIN:-default}
 HEAT_BIN_DIR=$(get_python_exec_prefix)
 HEAT_API_UWSGI_CONF=$HEAT_CONF_DIR/heat-api-uwsgi.ini
 HEAT_CFN_API_UWSGI_CONF=$HEAT_CONF_DIR/heat-api-cfn-uwsgi.ini
-HEAT_API_UWSGI=$HEAT_BIN_DIR/heat-wsgi-api
-HEAT_CFN_API_UWSGI=$HEAT_BIN_DIR/heat-wsgi-api-cfn
+HEAT_API_UWSGI=heat.wsgi.api:application
+HEAT_CFN_API_UWSGI=heat.wsgi.cfn:application
 
 # Flag to set the oslo_policy.enforce_scope and oslo_policy.enforce_new_defaults.
 # This is used to disable the compute API policies scope and new defaults.
@@ -159,12 +159,12 @@ function configure_heat {
 
     if [[ "$HEAT_USE_APACHE" == "True" ]]; then
         if [[ $WSGI_MODE == "uwsgi" ]]; then
-            write_uwsgi_config "$HEAT_API_UWSGI_CONF" "$HEAT_API_UWSGI" "/heat-api"
+            write_uwsgi_config "$HEAT_API_UWSGI_CONF" "$HEAT_API_UWSGI" "/heat-api" "" "heat-api"
             # configure threads for h-api to avoid IO wait and messaging timeout. We use
             # 'nproc/4' to calculate API workers, hence, 4 would be probably correct
             # approximation.
             iniset "$HEAT_API_UWSGI_CONF" uwsgi threads 4
-            write_uwsgi_config "$HEAT_CFN_API_UWSGI_CONF" "$HEAT_CFN_API_UWSGI" "/heat-api-cfn"
+            write_uwsgi_config "$HEAT_CFN_API_UWSGI_CONF" "$HEAT_CFN_API_UWSGI" "/heat-api-cfn" "" "heat-api-cfn"
         else
             _config_heat_apache_wsgi
         fi
@@ -368,11 +368,11 @@ function _config_heat_apache_wsgi {
     local heat_cfn_api_port=$HEAT_API_CFN_PORT
     local venv_path=""
 
-    sudo cp $HEAT_FILES_DIR/heat-api.conf $heat_apache_conf
+    sudo cp $HEAT_HTTPD_VHOST_FILES_DIR/heat-api.conf $heat_apache_conf
     sudo sed -e "
         s|%PUBLICPORT%|$heat_api_port|g;
         s|%APACHE_NAME%|$APACHE_NAME|g;
-        s|%HEAT_BIN_DIR%|$HEAT_BIN_DIR|g;
+        s|%HEAT_DIR%|$HEAT_DIR|g;
         s|%API_WORKERS%|$API_WORKERS|g;
         s|%SSLENGINE%|$heat_ssl|g;
         s|%SSLCERTFILE%|$heat_certfile|g;
@@ -381,11 +381,11 @@ function _config_heat_apache_wsgi {
         s|%VIRTUALENV%|$venv_path|g
     " -i $heat_apache_conf
 
-    sudo cp $HEAT_FILES_DIR/heat-api-cfn.conf $heat_cfn_apache_conf
+    sudo cp $HEAT_HTTPD_VHOST_FILES_DIR/heat-api-cfn.conf $heat_cfn_apache_conf
     sudo sed -e "
         s|%PUBLICPORT%|$heat_cfn_api_port|g;
         s|%APACHE_NAME%|$APACHE_NAME|g;
-        s|%HEAT_BIN_DIR%|$HEAT_BIN_DIR|g;
+        s|%HEAT_DIR%|$HEAT_DIR|g;
         s|%API_WORKERS%|$API_WORKERS|g;
         s|%SSLENGINE%|$heat_ssl|g;
         s|%SSLCERTFILE%|$heat_certfile|g;

doc/source/conf.py

@@ -180,10 +180,10 @@ apidoc_excluded_paths = [
     'engine/resources/aws',
     'engine/resources/openstack',
     'hacking',
-    'httpd',
     'locale',
     'tests',
     'version.py',
+    'wsgi',
 ]
 
 

etc/heat/httpd/heat-api-cfn.conf

@@ -3,7 +3,7 @@ Listen %PUBLICPORT%
 <VirtualHost *:%PUBLICPORT%>
     WSGIDaemonProcess heat-api-cfn processes=%API_WORKERS% threads=1 user=%USER% display-name=%{GROUP} %VIRTUALENV%
     WSGIProcessGroup heat-api-cfn
-    WSGIScriptAlias / %HEAT_BIN_DIR%/heat-wsgi-api-cfn
+    WSGIScriptAlias / %HEAT_DIR%/cfn/wsgi.py
     WSGIApplicationGroup %{GLOBAL}
     WSGIPassAuthorization On
     AllowEncodedSlashes On

etc/heat/httpd/heat-api.conf

@@ -3,7 +3,7 @@ Listen %PUBLICPORT%
 <VirtualHost *:%PUBLICPORT%>
     WSGIDaemonProcess heat-api processes=%API_WORKERS% threads=10 user=%USER% display-name=%{GROUP} %VIRTUALENV%
     WSGIProcessGroup heat-api
-    WSGIScriptAlias / %HEAT_BIN_DIR%/heat-wsgi-api
+    WSGIScriptAlias / %HEAT_DIR%/api/wsgi.py
     WSGIApplicationGroup %{GLOBAL}
     WSGIPassAuthorization On
     AllowEncodedSlashes On

etc/heat/uwsgi/heat-api-cfn-uwsgi.ini

@@ -11,4 +11,4 @@ die-on-term = true
 master = true
 processes = 4
 http = 127.0.0.1:80998
-wsgi-file = /usr/local/bin/heat-wsgi-api-cfn
+module = heat.wsgi.cfn:application

etc/heat/uwsgi/heat-api-uwsgi.ini

@@ -11,4 +11,4 @@ die-on-term = true
 master = true
 processes = 4
 http = 127.0.0.1:80999
-wsgi-file = /usr/local/bin/heat-wsgi-api
+module = heat.wsgi.api:application

heat/httpd/files/uwsgi-heat-api-cfn.conf

@@ -1,2 +0,0 @@
-KeepAlive Off
-ProxyPass "/heat-api-cfn" "http://127.0.0.1:80998" retry=0

heat/httpd/files/uwsgi-heat-api.conf

@@ -1,2 +0,0 @@
-KeepAlive Off
-ProxyPass "/heat-api" "http://127.0.0.1:80999" retry=0

heat/wsgi/api.py

@@ -0,0 +1,24 @@
+# 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.
+
+"""WSGI application entry-point for the Heat API."""
+
+import threading
+
+from heat.api.openstack import wsgi
+
+application = None
+
+lock = threading.Lock()
+with lock:
+    if application is None:
+        application = wsgi.init_application()

heat/wsgi/cfn.py

@@ -0,0 +1,24 @@
+# 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.
+
+"""WSGI application entry-point for the Heat API."""
+
+import threading
+
+from heat.api.cfn import wsgi
+
+application = None
+
+lock = threading.Lock()
+with lock:
+    if application is None:
+        application = wsgi.init_application()

releasenotes/notes/add-heat-wsgi-module-bd75e71b4fc47568.yaml

@@ -0,0 +1,22 @@
+---
+features:
+  - |
+    A new module, ``heat.wsgi``, has been added as a place to gather WSGI
+    ``application`` objects. This is intended to ease deployment by providing
+    a consistent location for these objects. For example, if using uWSGI then
+    instead of:
+
+    .. code-block:: ini
+
+        [uwsgi]
+        wsgi-file = /bin/heat-api
+
+    You can now use:
+
+    .. code-block:: ini
+
+        [uwsgi]
+        module = heat.wsgi.api:application
+
+    This also simplifies deployment with other WSGI servers that expect module
+    paths such as gunicorn.

setup.cfg

@@ -43,8 +43,8 @@ console_scripts =
     heat-status = heat.cmd.status:main
 
 wsgi_scripts =
-    heat-wsgi-api = heat.httpd.heat_api:init_application
-    heat-wsgi-api-cfn = heat.httpd.heat_api_cfn:init_application
+    heat-wsgi-api = heat.api.openstack.wsgi:init_application
+    heat-wsgi-api-cfn = heat.api.cfn.wsgi:init_application
 
 oslo.config.opts =
     heat.common.cache = heat.common.cache:list_opts