branchmap: allow to use cache of subset
Filtered repository are *subset* of unfiltered repository. This means that a
filtered branchmap could be use to compute the unfiltered version.
And filtered version happen to be subset of each other:
- "all() - unserved()" is a subset of "all() - hidden()"
- "all() - hidden()" is a subset of "all()"
This means that branchmap with "unfiltered" filter can be used as a base for
"hidden" branchmap that itself could be used as a base for unfiltered
branchmap.
unserved < hidden < None
This changeset implements this mechanism. If the on disk branchcache is not valid
we use the branchcache of the nearest subset as base instead of computing it from
scratch. Such fallback can be cascaded multiple time is necessary.
Note that both "hidden" and "unserved" set are a bit volatile. We will add more
stable filtering in next changesets.
This changeset enables collaboration between no filtering and "unserved"
filtering. Fixing performance regression introduced by 47f00b0de337
[ original upstream message ]
#!/usr/bin/env python
"""This does HTTP GET requests given a host:port and path and returns
a subset of the headers plus the body of the result."""
import httplib, sys
try:
import msvcrt, os
msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
msvcrt.setmode(sys.stderr.fileno(), os.O_BINARY)
except ImportError:
pass
twice = False
if '--twice' in sys.argv:
sys.argv.remove('--twice')
twice = True
reasons = {'Not modified': 'Not Modified'} # python 2.4
tag = None
def request(host, path, show):
assert not path.startswith('/'), path
global tag
headers = {}
if tag:
headers['If-None-Match'] = tag
conn = httplib.HTTPConnection(host)
conn.request("GET", '/' + path, None, headers)
response = conn.getresponse()
print response.status, reasons.get(response.reason, response.reason)
for h in [h.lower() for h in show]:
if response.getheader(h, None) is not None:
print "%s: %s" % (h, response.getheader(h))
print
data = response.read()
sys.stdout.write(data)
if twice and response.getheader('ETag', None):
tag = response.getheader('ETag')
return response.status
status = request(sys.argv[1], sys.argv[2], sys.argv[3:])
if twice:
status = request(sys.argv[1], sys.argv[2], sys.argv[3:])
if 200 <= status <= 305:
sys.exit(0)
sys.exit(1)