diff options
Diffstat (limited to 'python/walmgr.py')
| -rwxr-xr-x | python/walmgr.py | 191 |
1 files changed, 127 insertions, 64 deletions
diff --git a/python/walmgr.py b/python/walmgr.py index 67ce9927..4725427a 100755 --- a/python/walmgr.py +++ b/python/walmgr.py @@ -168,6 +168,66 @@ class BackupLabel: if m: self.label_string = m.group(1) +class PostgresConfiguration: + """Postgres configuration manipulation""" + + def __init__(self, walmgr): + """load the configuration from master_config""" + self.walmgr = walmgr + self.log = walmgr.log + self.cf_file = walmgr.cf.get("master_config") + self.cf_buf = open(self.cf_file, "r").read() + + def param_value(self, param_name): + """Return value for specified parameter""" + m = re.search("^\s*%s\s*=\s*'?(.*)'?\s*#?.*$" % param_name, self.cf_buf, re.M | re.I) + if m: + return m.group(1) + return None + + def modify(self, cf_params): + """Change the configuration parameters supplied in cf_params""" + + for (param, value) in cf_params.iteritems(): + r_active = re.compile("^[ ]*%s[ ]*=[ ]*'(.*)'.*$" % param, re.M) + r_disabled = re.compile("^.*%s.*$" % param, re.M) + + cf_full = "%s = '%s'" % (param, value) + + m = r_active.search(self.cf_buf) + if m: + old_val = m.group(1) + if old_val == value: + self.log.debug("parameter %s already set to '%s'" % (param, value)) + else: + self.log.debug("found parameter %s with value '%s'" % (param, old_val)) + self.cf_buf = "%s%s%s" % (self.cf_buf[:m.start()], cf_full, self.cf_buf[m.end():]) + else: + m = r_disabled.search(self.cf_buf) + if m: + self.log.debug("found disabled parameter %s" % param) + self.cf_buf = "%s\n%s%s" % (self.cf_buf[:m.end()], cf_full, self.cf_buf[m.end():]) + else: + self.log.debug("found no value") + self.cf_buf = "%s\n%s\n\n" % (self.cf_buf, cf_full) + + def write(self): + """Write the configuration back to file""" + cf_old = self.cf_file + ".old" + cf_new = self.cf_file + ".new" + + if self.walmgr.not_really: + cf_new = "/tmp/postgresql.conf.new" + open(cf_new, "w").write(self.cf_buf) + self.log.info("Showing diff") + os.system("diff -u %s %s" % (self.cf_file, cf_new)) + self.log.info("Done diff") + os.remove(cf_new) + return + + # polite method does not work, as usually not enough perms for it + open(self.cf_file, "w").write(self.cf_buf) + class WalMgr(skytools.DBScript): def init_optparse(self, parser=None): @@ -322,6 +382,12 @@ class WalMgr(skytools.DBScript): self.log.fatal("exec failed, res=%d (%s)" % (res, repr(cmdline))) sys.exit(1) + def exec_system(self, cmdline): + self.log.debug("Execute cmd: '%s'" % (cmdline)) + if self.not_really: + return 0 + return os.WEXITSTATUS(os.system(cmdline)) + def chdir(self, loc): self.log.debug("chdir: '%s'" % (loc)) if self.not_really: @@ -364,10 +430,21 @@ class WalMgr(skytools.DBScript): def master_stop(self): """Deconfigure archiving, attempt to stop syncdaemon""" + data_dir = self.cf.get("master_data") + restart_cmd = self.cf.get("master_restart_cmd", "") + self.assert_valid_role(MASTER) self.log.info("Disabling WAL archiving") - self.master_configure_archiving('') + self.master_configure_archiving(False, restart_cmd) + + # if we have a restart command, then use it, otherwise signal + if restart_cmd: + self.log.info("Restarting postmaster") + self.exec_system(restart_cmd) + else: + self.log.info("Sending SIGHUP to postmaster") + self.signal_postmaster(data_dir, signal.SIGHUP) # stop any running syncdaemons pidfile = self.cf.get("pidfile") @@ -376,63 +453,43 @@ class WalMgr(skytools.DBScript): self.exec_cmd([self.script, self.cfgfile, "syncdaemon", "-s"]) self.log.info("Done") - def master_configure_archiving(self, cf_val): - cf_file = self.cf.get("master_config") - data_dir = self.cf.get("master_data") - r_active = re.compile("^[ ]*archive_command[ ]*=[ ]*'(.*)'.*$", re.M) - r_disabled = re.compile("^.*archive_command.*$", re.M) + def master_configure_archiving(self, enable_archiving, can_restart): + """Turn the archiving on or off""" - cf_full = "archive_command = '%s'" % cf_val + cf = PostgresConfiguration(self) - if not os.path.isfile(cf_file): - self.log.fatal("Config file not found: %s" % cf_file) - self.log.info("Using config file: %s", cf_file) + if enable_archiving: + # enable archiving + cf_file = os.path.abspath(self.cf.filename) + xarchive = "%s %s %s" % (self.script, cf_file, "xarchive %p %f") + cf_params = { "archive_command": xarchive } - buf = open(cf_file, "r").read() - m = r_active.search(buf) - if m: - old_val = m.group(1) - if old_val == cf_val: - self.log.debug("postmaster already configured") + if cf.param_value('archive_mode'): + # archive mode specified in config, turn it on + self.log.debug("found 'archive_mode' in config -- enabling it") + cf_params["archive_mode"] = "on" else: - self.log.debug("found active but different conf") - newbuf = "%s%s%s" % (buf[:m.start()], cf_full, buf[m.end():]) - self.change_config(cf_file, newbuf) + self.log.debug("seems that archive_mode is not set, ignoring it.") + else: - m = r_disabled.search(buf) - if m: - self.log.debug("found disabled value") - newbuf = "%s\n%s%s" % (buf[:m.end()], cf_full, buf[m.end():]) - self.change_config(cf_file, newbuf) + # disable archiving + if not cf.param_value('archive_mode'): + # archive_mode not set, just reset archive_command and its done + self.log.debug("archive_mode not set in config, leaving as is") + cf_params = { "archive_command": "" } + elif can_restart: + # restart possible, turn off archiving, reset archive_command + cf_params = { "archive_mode": "off", "archive_command": "" } else: - self.log.debug("found no value") - newbuf = "%s\n%s\n\n" % (buf, cf_full) - self.change_config(cf_file, newbuf) - - self.log.info("Sending SIGHUP to postmaster") - self.signal_postmaster(data_dir, signal.SIGHUP) + # not possible to change archive_mode (requires restart), so we + # just set the archive_command to /bin/true to avoid WAL pileup. + self.log.debug("master_restart_cmd not specified, leaving archive_mode as is") + cf_params = { "archive_command": "/bin/true" } - def change_config(self, cf_file, buf): - cf_old = cf_file + ".old" - cf_new = cf_file + ".new" + self.log.debug("modifying configuration: %s" % cf_params) - if self.not_really: - cf_new = "/tmp/postgresql.conf.new" - open(cf_new, "w").write(buf) - self.log.info("Showing diff") - os.system("diff -u %s %s" % (cf_file, cf_new)) - self.log.info("Done diff") - os.remove(cf_new) - return - - # polite method does not work, as usually not enough perms for it - if 0: - open(cf_new, "w").write(buf) - bak = open(cf_file, "r").read() - open(cf_old, "w").write(bak) - os.rename(cf_new, cf_file) - else: - open(cf_file, "w").write(buf) + cf.modify(cf_params) + cf.write() def remote_mkdir(self, remdir): tmp = remdir.split(":", 1) @@ -473,10 +530,19 @@ class WalMgr(skytools.DBScript): if self.wtype == MASTER: self.log.info("Configuring WAL archiving") - cf_file = os.path.abspath(self.cf.filename) - cf_val = "%s %s %s" % (self.script, cf_file, "xarchive %p %f") + data_dir = self.cf.get("master_data") + restart_cmd = self.cf.get("master_restart_cmd", "") + + self.master_configure_archiving(True, restart_cmd) + + # if we have a restart command, then use it, otherwise signal + if restart_cmd: + self.log.info("Restarting postmaster") + self.exec_system(restart_cmd) + else: + self.log.info("Sending SIGHUP to postmaster") + self.signal_postmaster(data_dir, signal.SIGHUP) - self.master_configure_archiving(cf_val) # ask slave to init self.remote_walmgr("setup") self.log.info("Done") @@ -515,7 +581,7 @@ class WalMgr(skytools.DBScript): self.log.info("Running periodic command: %s" % periodic_command) if not elapsed or elapsed > command_interval: if not self.not_really: - rc = os.WEXITSTATUS(os.system(periodic_command)) + rc = os.WEXITSTATUS(self.exec_system(periodic_command)) if rc != 0: self.log.error("Periodic command exited with status %d" % rc) # dont update timestamp - try again next time @@ -1093,9 +1159,8 @@ STOP TIME: %(stop_time)s # stop postmaster if ordered if stop_cmd and os.path.isfile(pidfile): self.log.info("Stopping postmaster: " + stop_cmd) - if not self.not_really: - os.system(stop_cmd) - time.sleep(3) + self.exec_system(stop_cmd) + time.sleep(3) # is it dead? if pidfile and os.path.isfile(pidfile): @@ -1215,8 +1280,7 @@ STOP TIME: %(stop_time)s # run database in recovery mode self.log.info("Starting postmaster: " + start_cmd) - if not self.not_really: - os.system(start_cmd) + self.exec_system(start_cmd) else: self.log.info("Data files restored, recovery.conf created.") self.log.info("postgresql.conf and additional WAL files may need to be restored manually.") @@ -1424,11 +1488,10 @@ STOP TIME: %(stop_time)s if archive_command: cmdline = archive_command.replace("$BACKUPDIR", last) self.log.info("Executing archive_command: " + cmdline) - if not self.not_really: - rc = os.WEXITSTATUS(os.system(cmdline)) - if rc != 0: - self.log.error("Backup archiving returned %d, exiting!" % rc) - sys.exit(1) + rc = self.exec_system(cmdline) + if rc != 0: + self.log.error("Backup archiving returned %d, exiting!" % rc) + sys.exit(1) self.log.info("Removing expired backup directory: %s" % last) if self.not_really: |