Merge changes from psycopg2/trunk via psycopg2.r243.

1 files changed, 79 insertions, 0 deletions

diff --git a/examples/lobject.py b/examples/lobject.py
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index 0000000..182c951
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+++ b/examples/lobject.py
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+# lobject.py - lobject example
+#
+# Copyright (C) 2001-2006 Federico Di Gregorio  <fog@debian.org>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by the
+# Free Software Foundation; either version 2, or (at your option) any later
+# version.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTIBILITY
+# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+# for more details.
+
+## put in DSN your DSN string
+
+DSN = 'dbname=test'
+
+## don't modify anything below this line (except for experimenting)
+
+import sys
+import psycopg2
+
+if len(sys.argv) > 1:
+    DSN = sys.argv[1]
+
+print "Opening connection using dns:", DSN
+conn = psycopg2.connect(DSN)
+print "Encoding for this connection is", conn.encoding
+
+# this will create a large object with a new random oid, we'll
+# use it to make some basic tests about read/write and seek.
+lobj = conn.lobject()
+loid = lobj.oid
+print "Created a new large object with oid", loid
+
+print "Manually importing some binary data into the object:"
+data = open("somehackers.jpg").read()
+len = lobj.write(data)
+print "  imported", len, "bytes of data"
+
+conn.commit()
+
+print "Trying to (re)open large object with oid", loid
+lobj = conn.lobject(loid)
+print "Manually exporting the data from the lobject:"
+data1 = lobj.read()
+len = lobj.tell()
+lobj.seek(0, 0)
+data2 = lobj.read()
+if data1 != data2:
+    print "ERROR: read after seek returned different data"
+open("somehackers_lobject1.jpg", 'wb').write(data1)
+print "  written", len, "bytes of data to somehackers_lobject1.jpg"
+
+lobj.unlink()
+print "Large object with oid", loid, "removed"
+
+conn.commit()
+
+# now we try to use the import and export functions to do the same
+lobj = conn.lobject(0, 'n', 0, "somehackers.jpg")
+loid = lobj.oid
+print "Imported a new large object with oid", loid
+
+conn.commit()
+
+print "Trying to (re)open large object with oid", loid
+lobj = conn.lobject(loid, 'n')
+print "Using export() to export the data from the large object:"
+lobj.export("somehackers_lobject2.jpg")
+print "  exported large object to somehackers_lobject2.jpg"
+
+lobj.unlink()
+print "Large object with oid", loid, "removed"
+
+conn.commit()
+
+print "\nNow try to load the new images, to check it worked!"