Using Unrestricted Languages - PostgreSQL Server Programming - page 196

turing; if it is called with the argument, do_capture set to false , and the second
one returns everything captured:
CREATE OR REPLACE FUNCTION
capture_stdout(do_capture bool)
RETURNS text
AS $$
import sys
if do_capture:
try:
sys.stdout = GD['stdout_to_notice']
except KeyError:
class WriteAsNotice:
def __init__(self, old_stdout):
self.old_stdout = old_stdout
self.printed = []
def write(self, s):
self.printed.append(s)
def read(self):
text = ''.join(self.printed)
self.printed = []
return text
GD['stdout_to_notice'] =
WriteAsNotice(sys.stdout)
sys.stdout = GD['stdout_to_notice']
return "sys.stdout captured"
else:
sys.stdout =
SD['stdout_to_notice'].old_stdout
return "restored original sys.stdout"
$$ LANGUAGE plpythonu;
CREATE OR REPLACE FUNCTION read_stdout()
RETURNS text
AS $$
return GD['stdout_to_notice'].read()
$$ LANGUAGE plpythonu;