Merge "Rework swift_rings.py to use the RingBuilder class"

This commit is contained in:
Jenkins 2017-03-10 12:46:17 +00:00 committed by Gerrit Code Review
commit 3a1b7c5387

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@ -15,14 +15,16 @@
from __future__ import print_function
from optparse import OptionParser
from os.path import exists
from os.path import exists, dirname, join, basename
from swift.cli.ringbuilder import main as rb_main
from swift.common.ring import RingBuilder
from swift.common.ring.utils import parse_builder_ring_filename_args
import json
import pickle
import sys
import threading
import os
import time
from datetime import timedelta
USAGE = "usage: %prog -f <swift_ring.contents> -r <managed_region>"
@ -36,54 +38,8 @@ class RingValidationError(Exception):
pass
class ThreadWithErr(threading.Thread):
def run(self):
try:
threading.Thread.run(self)
except BaseException as err:
self.err = err
else:
self.err = None
def create_buildfile(build_file, part_power, repl, min_part_hours,
update=False, data=None, validate=False):
if update:
# build file exists, so lets just update the existing build file
if not data:
data = get_build_file_data(build_file)
if data is None:
data = {}
if repl != data.get('replicas') and not validate:
run_and_wait(rb_main, ["swift-ring-builder", build_file,
"set_replicas", repl])
if min_part_hours != data.get('min_part_hours') and not validate:
run_and_wait(rb_main, ["swift-ring-builder", build_file,
"set_min_part_hours", min_part_hours])
if part_power != data.get('part_power'):
raise RingValidationError('Part power cannot be changed! '
'you must rebuild the ring if you need '
'to change it.\nRing part power: %s '
'Inventory part power: %s'
% (data.get('part_power'), part_power))
elif not validate:
run_and_wait(rb_main, ["swift-ring-builder", build_file, "create",
part_power, repl, min_part_hours])
def change_host_weight(build_file, host_search_str, weight):
run_and_wait(rb_main, ["swift-ring-builder", build_file, "set_weight",
host_search_str, str(weight)])
def remove_host_from_ring(build_file, host):
run_and_wait(rb_main, ["swift-ring-builder", build_file, "remove",
host])
def update_host_in_ring(build_file, new_host, old_host, validate=False):
def update_host_in_ring(ringbuilder, new_host, old_host, old_host_idx,
validate=False):
if new_host.get('zone', 0) != old_host['zone']:
devstr = DEVICE_KEY % new_host
raise RingValidationError('Cannot update zone on %s, this can only be '
@ -102,111 +58,115 @@ def update_host_in_ring(build_file, new_host, old_host, validate=False):
if new_host_str != old_host_str:
if not validate:
run_and_wait(rb_main, ["swift-ring-builder", build_file,
"set_info", old_host_str,
new_host_str])
ringbuilder.devs[old_host_idx].update(new_host)
ringbuilder.devs_changed = True
ringbuilder.version += 1
except Exception as ex:
raise RingValidationError(ex)
if new_weight != old_weight and not validate:
change_host_weight(build_file, FULL_HOST_KEY % new_host, new_weight)
ringbuilder.set_dev_weight(ringbuilder.devs[old_host_idx]['id'],
new_weight)
def add_host_to_ring(build_file, host, validate=False):
host_str = ""
def add_host_to_ring(ringbuilder, host, validate=False):
new_host = {'region': 1, 'zone': 0, 'meta': ''}
new_host.update(host)
try:
if host.get('region') is not None:
host_str += 'r%(region)d' % host
host_str += "z%(zone)d-" % host
host_str += FULL_HOST_KEY % host
weight = host.get('weight')
if validate:
ringbuilder.add_dev(new_host)
except Exception as ex:
raise RingValidationError(ex)
if not validate:
run_and_wait(rb_main, ["swift-ring-builder", build_file, 'add',
host_str, str(weight)])
def run_and_wait(func, *args):
t = ThreadWithErr(target=func, args=args)
t.start()
t.join()
if t.err and t.err.code > 0:
sys.exit(t.err.code)
def get_build_file_data(build_file):
build_file_data = None
if exists(build_file):
try:
with open(build_file) as bf_stream:
build_file_data = pickle.load(bf_stream)
except Exception as ex:
print("Error: failed to load build file '%s': %s" % (build_file,
ex))
build_file_data = None
return build_file_data
def build_ring(build_name, repl, min_part_hours, part_power, hosts,
region=None, validate=False, reset_mph_clock=False):
# Create the build file
build_file = "%s.builder" % build_name
build_file_data = get_build_file_data(build_file)
if exists(build_file):
ringbuilder = RingBuilder.load(build_file)
else:
ringbuilder = RingBuilder(part_power, repl, min_part_hours)
update = build_file_data is not None
create_buildfile(
build_file,
part_power,
repl,
min_part_hours,
update,
data=build_file_data,
validate=validate
)
# run some checks
if repl != ringbuilder.replicas and not validate:
ringbuilder.set_replicas(repl)
if min_part_hours != ringbuilder.min_part_hours and not validate:
ringbuilder.change_min_part_hours(min_part_hours)
if part_power != ringbuilder.part_power:
raise RingValidationError(
'Part power cannot be changed! you must rebuild the ring if you '
'need to change it.\nRing part power: %s Inventory part power: %s'
% (ringbuilder.part_power, part_power))
old_hosts = {}
if update:
for i, dev in enumerate(build_file_data['devs']):
if dev is not None:
if region is None or int(region) == int(dev['region']):
old_hosts[DEVICE_KEY % dev] = i
for i, dev in enumerate(ringbuilder.devs):
if dev is not None:
if region is None or int(region) == int(dev['region']):
old_hosts[DEVICE_KEY % dev] = i
for host in hosts:
host_key = DEVICE_KEY % host
if region is None or int(region) == int(host['region']):
if host_key in old_hosts:
old_host = build_file_data['devs'][old_hosts[host_key]]
update_host_in_ring(build_file, host, old_host,
validate=validate)
old_host = ringbuilder.devs[old_hosts[host_key]]
update_host_in_ring(ringbuilder, host, old_host,
old_hosts[host_key], validate=validate)
old_hosts.pop(host_key)
else:
add_host_to_ring(build_file, host, validate=validate)
add_host_to_ring(ringbuilder, host, validate=validate)
if old_hosts and not validate:
# There are still old hosts, these hosts must've been removed
for host in old_hosts:
remove_host_from_ring(build_file, host)
try:
for host, idx in old_hosts.items():
ringbuilder.remove_dev(ringbuilder.devs[idx]['id'])
except Exception as ex:
raise RingValidationError(ex)
build_file, ring_file = parse_builder_ring_filename_args(('', build_file))
# serialise to disk before we think about writing the ring
backup_folder = join(dirname(build_file), 'backups')
try:
os.mkdir(backup_folder)
except OSError:
if not os.path.isdir(backup_folder):
raise
ts = time.time()
ringbuilder.save(build_file)
ringbuilder.save(join(backup_folder, '%d.' % ts + basename(build_file)))
# Rebalance ring
if not validate:
if not hosts:
run_and_wait(
rb_main, ["swift-ring-builder", build_file, "write_ring"]
)
ringdata = ringbuilder.get_ring()
ringdata.save(join(backup_folder, '%d.' % ts +
basename(ring_file)))
ringdata.save(ring_file)
else:
if reset_mph_clock:
run_and_wait(
rb_main, ["swift-ring-builder", build_file,
"pretend_min_part_hours_passed"]
)
run_and_wait(
rb_main, ["swift-ring-builder", build_file, "rebalance"]
)
# In case no changes that require a rebalance have happened
# We may still need to write the ring for device changes.
run_and_wait(
rb_main, ["swift-ring-builder", build_file, "write_ring"]
)
ringbuilder.pretend_min_part_hours_passed()
if ringbuilder.min_part_seconds_left > 0:
raise RingValidationError(
'The time between rebalances must be at least '
'min_part_hours: %s hours (%s remaining)' %
(ringbuilder.min_part_hours,
timedelta(seconds=ringbuilder.min_part_seconds_left)))
exit(2)
parts, balance, removed_devs = ringbuilder.rebalance()
try:
ringbuilder.validate()
except Exception as ex:
raise RingValidationError(ex)
ringbuilder.save(join(backup_folder, '%d.' % ts +
basename(build_file)))
ringbuilder.save(build_file)
ringdata = ringbuilder.get_ring()
ringdata.save(join(backup_folder, '%d.' % ts +
basename(ring_file)))
ringdata.save(ring_file)
def main(setup, region, reset_mph_clock):