Add PBR wsgi_scripts entrypoint for barbican api

This commit makes the barbican wsgi script consistent with other
services by leveraging the pbr wsgi_scripts entrypoint to expose it.
While you could still leverage the bundled app.wsgi the entrypoint
barbican's behavior the same as other services. As part of this the
app.wsgi script is deprecated and will be removed in the future.

Change-Id: Id42f76dbfd59209232b37096a708ee18cbf96431

barbican/api/app.py

@@ -18,6 +18,7 @@ API application handler for Barbican
 """
 import os
 
+from paste import deploy
 import pecan
 
 try:
@@ -101,3 +102,9 @@ def create_main_app(global_config, **local_conf):
 def create_version_app(global_config, **local_conf):
     wsgi_app = pecan.make_app(versions.VersionsController())
     return wsgi_app
+
+
+def get_api_wsgi_script():
+    conf = '/etc/barbican/barbican-api-paste.ini'
+    application = deploy.loadapp('config:%s' % conf)
+    return application

barbican/api/app.wsgi

@@ -16,10 +16,11 @@
 """Use this file for deploying the API under mod_wsgi.
 
 See http://pecan.readthedocs.org/en/latest/deployment.html for details.
+
+NOTE(mtreinish): This wsgi script is deprecated since the wsgi app is now
+exposed as an entrypoint via barbican-wsgi-api
 """
 
-from paste import deploy
+from barbican.api import app
-
-conf = '/etc/barbican/barbican-api-paste.ini'
-application = deploy.loadapp('config:%s' % conf)
 
+application = app.get_api_wsgi_script()

setup.cfg

@@ -40,6 +40,9 @@ console_scripts =
     pkcs11-key-generation = barbican.cmd.pkcs11_key_generation:main
     barbican-retry = barbican.cmd.retry_scheduler:main
 
+wsgi_scripts =
+    barbican-wsgi-api = barbican.api.app:get_api_wsgi_script
+
 barbican.secretstore.plugin =
     store_crypto = barbican.plugin.store_crypto:StoreCryptoAdapterPlugin
     dogtag_crypto = barbican.plugin.dogtag:DogtagKRAPlugin