From be12175c8a98acb7dd35405a2634ee681fb7ce1e Mon Sep 17 00:00:00 2001
From: "roberto@sirius" <roberto@sirius>
Date: Tue, 20 Apr 2010 10:19:00 +0200
Subject: [PATCH] psycopg2 async example

---
 tests/psycopg2_green.py | 50 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 tests/psycopg2_green.py

diff --git a/tests/psycopg2_green.py b/tests/psycopg2_green.py
new file mode 100644
index 00000000..e2e04faf
--- /dev/null
+++ b/tests/psycopg2_green.py
@@ -0,0 +1,50 @@
+import uwsgi
+import psycopg2
+
+def async_wait(conn):
+	# conn can be a connection or a cursor
+	if not hasattr(conn, 'poll'):
+		conn = conn.connection
+	
+	# interesting part: suspend until ready
+	while True:
+		state = conn.poll()
+		if state == psycopg2.extensions.POLL_OK:
+			break
+		elif state == psycopg2.extensions.POLL_READ:
+			uwsgi.green_wait_fdread(conn.fileno())
+		elif state == psycopg2.extensions.POLL_WRITE:
+			uwsgi.green_wait_fdwrite(conn.fileno())
+		else:
+			raise Exception("Unexpected result from poll: %r", state)
+
+			
+
+
+
+def application(env, start_response):
+
+	start_response('200 Ok', [('Content-type', 'text/html')])
+
+	conn = psycopg2.connect("dbname=prova user=postgres", async=True)
+
+	# suspend until connection
+	async_wait(conn)
+
+	curs = conn.cursor()
+
+	yield "<table>"
+
+	curs.execute("SELECT * FROM tests")
+
+	# suspend until result
+	async_wait(curs)
+
+	while True:
+		row = curs.fetchone()
+		if not row: break
+		yield "<tr><td>%s</td></tr>" % str(row)
+
+	yield "</table>"
+
+	conn.close()