From 6af3a6fc41462e5b55d4abd4b224b8e15cbb8b31 Mon Sep 17 00:00:00 2001
From: Jim Paris <jim@jtan.com>
Date: Fri, 22 Mar 2013 19:14:34 -0400
Subject: [PATCH] Add WSGI application support and documentation

---
 README.txt                |  2 ++
 docs/wsgi.md              | 18 ++++++++++++++++++
 nilmdb/server/__init__.py |  2 +-
 nilmdb/server/server.py   | 15 +++++++++++++++
 4 files changed, 36 insertions(+), 1 deletion(-)
 create mode 100644 docs/wsgi.md

diff --git a/README.txt b/README.txt
index 9adc4d2..d7c8227 100644
--- a/README.txt
+++ b/README.txt
@@ -24,3 +24,5 @@ Usage:
 
   nilmdb-server --help
   nilmtool --help
+
+See docs/wsgi.md for info on setting up a WSGI application in Apache.
diff --git a/docs/wsgi.md b/docs/wsgi.md
new file mode 100644
index 0000000..8dc8a2f
--- /dev/null
+++ b/docs/wsgi.md
@@ -0,0 +1,18 @@
+WSGI Application in Apache
+--------------------------
+
+Apache configuration should look something like:
+
+    <VirtualHost>
+        WSGIScriptAlias /nilmdb /home/nilmdb/nilmdb.wsgi
+        WSGIApplicationGroup nilmdb
+        WSGIProcessGroup nilmdb
+        WSGIDaemonProcess nilmdb threads=32
+    </VirtualHost>
+	
+where `/home/nilmdb/nilmdb.wsgi` is a file containing:
+
+    import nilmdb.server
+	application = nilmdb.server.wsgi_application("/home/nilmdb/db")
+	
+where `/home/nilmdb/db` is the path to the database.
diff --git a/nilmdb/server/__init__.py b/nilmdb/server/__init__.py
index a903088..3c30990 100644
--- a/nilmdb/server/__init__.py
+++ b/nilmdb/server/__init__.py
@@ -17,5 +17,5 @@ except (ImportError, TypeError): # pragma: no cover
     pass
 
 from nilmdb.server.nilmdb import NilmDB
-from nilmdb.server.server import Server
+from nilmdb.server.server import Server, wsgi_application
 from nilmdb.server.errors import NilmDBError, StreamError, OverlapError
diff --git a/nilmdb/server/server.py b/nilmdb/server/server.py
index f9842a5..b34b7c8 100644
--- a/nilmdb/server/server.py
+++ b/nilmdb/server/server.py
@@ -536,6 +536,14 @@ class Server(object):
         else:
             cherrypy.server.shutdown_timeout = 5
 
+    def get_application(self):
+        """Return a WSGI application object"""
+        def app(environ, start_response):
+            if environ['wsgi.multiprocess']:
+                raise Exception("can't function in a multi-process environment")
+            return cherrypy.tree(environ, start_response)
+        return app
+
     def json_error_page(self, status, message, traceback, version):
         """Return a custom error page in JSON so the client can parse it"""
         errordata = { "status" : status,
@@ -602,3 +610,10 @@ class Server(object):
 
     def stop(self):
         cherrypy.engine.exit()
+
+def wsgi_application(dbpath):
+    """Return a WSGI application object with a database at the
+    specified path."""
+    db = nilmdb.utils.serializer_proxy(nilmdb.server.NilmDB)(dbpath)
+    server = nilmdb.server.Server(db, embedded = True)
+    return server.get_application()