From 8b1547cbe53c14208ea4001997b3c45453f60c95 Mon Sep 17 00:00:00 2001
From: Unrud <unrud@outlook.com>
Date: Fri, 20 Apr 2018 22:53:42 +0200
Subject: [PATCH] Move WSGI initialization into module

---
 radicale.fcgi        | 12 ++----------
 radicale.wsgi        | 13 +------------
 radicale/__init__.py | 24 +++++++++++++++++++++++-
 3 files changed, 26 insertions(+), 23 deletions(-)

diff --git a/radicale.fcgi b/radicale.fcgi
index 591afb06..52021abb 100755
--- a/radicale.fcgi
+++ b/radicale.fcgi
@@ -26,16 +26,8 @@ WSGI-to-FastCGI mapper.
 
 """
 
-import os
 from flup.server.fcgi import WSGIServer
-from radicale import Application, config, log
+from radicale import application
 
 
-config_paths = []
-if os.environ.get("RADICALE_CONFIG"):
-    config_paths.append(os.environ["RADICALE_CONFIG"])
-configuration = config.load(config_paths, ignore_missing_paths=False)
-filename = os.path.expanduser(configuration.get("logging", "config"))
-debug = configuration.getboolean("logging", "debug")
-logger = log.start("radicale", filename, debug)
-WSGIServer(Application(configuration, logger)).run()
+WSGIServer(application).run()
diff --git a/radicale.wsgi b/radicale.wsgi
index dbbd02c3..637ec9f6 100755
--- a/radicale.wsgi
+++ b/radicale.wsgi
@@ -21,15 +21,4 @@ Radicale WSGI file (mod_wsgi and uWSGI compliant).
 
 """
 
-import os
-from radicale import Application, config, log
-
-
-config_paths = []
-if os.environ.get("RADICALE_CONFIG"):
-    config_paths.append(os.environ["RADICALE_CONFIG"])
-configuration = config.load(config_paths, ignore_missing_paths=False)
-filename = os.path.expanduser(configuration.get("logging", "config"))
-debug = configuration.getboolean("logging", "debug")
-logger = log.start("radicale", filename, debug)
-application = Application(configuration, logger)
+from radicale import application
diff --git a/radicale/__init__.py b/radicale/__init__.py
index 82c2ea95..85828565 100644
--- a/radicale/__init__.py
+++ b/radicale/__init__.py
@@ -51,7 +51,7 @@ from xml.etree import ElementTree as ET
 
 import vobject
 
-from radicale import auth, rights, storage, web, xmlutils
+from radicale import auth, config, log, rights, storage, web, xmlutils
 
 
 VERSION = pkg_resources.get_distribution('radicale').version
@@ -949,3 +949,25 @@ class Application:
                     "Bad REPORT request on %r: %s", path, e, exc_info=True)
                 return BAD_REQUEST
             return (status, headers, self._write_xml_content(xml_answer))
+
+
+_application = None
+_application_lock = threading.Lock()
+
+
+def application(environ, start_response):
+    global _application
+    if _application is None:
+        with _application_lock:
+            if _application is None:
+                config_paths = []
+                if os.environ.get("RADICALE_CONFIG"):
+                    config_paths.append(os.environ["RADICALE_CONFIG"])
+                configuration = config.load(config_paths,
+                                            ignore_missing_paths=False)
+                filename = os.path.expanduser(configuration.get("logging",
+                                                                "config"))
+                debug = configuration.getboolean("logging", "debug")
+                logger = log.start("radicale", filename, debug)
+                _application = Application(configuration, logger)
+    return _application(environ, start_response)