tests/get-with-headers.py

revsetbenchmarks: allow running multiple variants per revset

The current benchmarks were only testing the whole iteration. This is suboptimal
because some changes are meaningful for things like first result, minimum or
sorting.

We introduce a "variants" feature that let you systematically add some variants
to all revsets tested.

A typical variants value would be 'plain,min,last,sort'. When testing 'all()' it
will also provide testing for:
- all()
- min(all())
- last(all())
- sort(sort)

and output:

   plain         min            last           sort
0) 0.034568      0.037857       0.000074       0.034238
1) 0.011358  32% 0.020181  53%  0.000080 108%  0.011405  33%

Using revsets (who hit the API) instead of the internal API add some overhead,
but the overhead should be the same everywhere so it still allow comparison.
This is is more simple to implement and allows comparison with older versions
who do not have the same API.

#!/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 json
except ImportError:
    try:
        import simplejson as json
    except ImportError:
        json = None

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
headeronly = False
if '--headeronly' in sys.argv:
    sys.argv.remove('--headeronly')
    headeronly = True
formatjson = False
if '--json' in sys.argv:
    sys.argv.remove('--json')
    formatjson = True

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, response.reason
    if show[:1] == ['-']:
        show = sorted(h for h, v in response.getheaders()
                      if h.lower() not in show)
    for h in [h.lower() for h in show]:
        if response.getheader(h, None) is not None:
            print "%s: %s" % (h, response.getheader(h))
    if not headeronly:
        print
        data = response.read()

        # Pretty print JSON. This also has the beneficial side-effect
        # of verifying emitted JSON is well-formed.
        if formatjson:
            if not json:
                print 'no json module not available'
                print 'did you forget a #require json?'
                sys.exit(1)

            # json.dumps() will print trailing newlines. Eliminate them
            # to make tests easier to write.
            data = json.loads(data)
            lines = json.dumps(data, sort_keys=True, indent=2).splitlines()
            for line in lines:
                print line.rstrip()
        else:
            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)