branch-rewrite.py doesn't flush and leaves the seat up

[Stuart Bishop]

scripts/branch-rewrite.py needs to explicitly flush sys.stdout after printing a response for Apache and there is no guarantee it will be done implicitly. If the flush doesn't occur, the whole system blocks.

[Stuart Bishop (stub)]

Needs to land for 3.1.11 or codehosting will likely fallover again.

[Tom Haddon (mthaddon)]

Diff is:

=== modified file 'scripts/branch-rewrite.py'
--- scripts/branch-rewrite.py 2009-07-24 07:08:33 +0000
+++ scripts/branch-rewrite.py 2009-11-05 12:31:00 +0000
@@ -53,6 +53,7 @@
                 # Mod-rewrite always gives us a newline terminated string.
                 if line:
                     print rewriter.rewriteLine(line.strip())
+ sys.stdout.flush()
                 else:
                     # Standard input has been closed, so die.
                     return

[Tom Haddon (mthaddon)]

Er, well, with proper indenting...

[Michael Hudson-Doyle (mwhudson)]

So what likely happened here is that the hashbang line in the script says "-u" and this wasn't carried over to invoking the script with "$rf/bin/py". It'd probably be a good idea to stick the -u back in -- otherwise I worry slightly about input buffering.

[Aaron Bentley (abentley)]

This has been fixed by supplying -u to the python interpreter, rather than using flush. This change has been made made in rewrite_wrapper.sh on crowberry (which is an unversioned file).