From bf435e2032a3faa48cb7c571c139fe4b0af344bf Mon Sep 17 00:00:00 2001 From: John Jarvis Date: Tue, 12 Nov 2013 19:02:01 -0500 Subject: [PATCH] Adding more wait conditions to the wait_for module Adds a new option to wait_for to wait for a file to exist on the file system before continuing, optionally takes a search_regex param to match text in the file. --- library/utilities/wait_for | 116 +++++++++++++++++++++++++++---------- 1 file changed, 86 insertions(+), 30 deletions(-) diff --git a/library/utilities/wait_for b/library/utilities/wait_for index fd7b8cbc29..8644673eb5 100644 --- a/library/utilities/wait_for +++ b/library/utilities/wait_for @@ -22,16 +22,20 @@ import socket import datetime import time import sys +import re DOCUMENTATION = ''' --- module: wait_for -short_description: Waits for a given port to become accessible on a server. +short_description: Waits for a condition before continuing. description: - - This is useful for when services are not immediately available after - their init scripts return - which is true of certain Java application - servers. It is also useful when starting guests with the M(virt) module and - needing to pause until they are ready. + - Waiting for a port to become available is useful for when services + are not immediately available after their init scripts return - + which is true of certain Java application servers. It is also + useful when starting guests with the M(virt) module and + needing to pause until they are ready. This module can + also be used to wait for a file to be available on the filesystem + or with a regex match a string to be present in a file. version_added: "0.7" options: host: @@ -53,21 +57,41 @@ options: port: description: - port number to poll - required: true + required: false state: description: - - either C(started), or C(stopped) depending on whether the module should - poll for the port being open or closed. - choices: [ "started", "stopped" ] + - either C(present), C(started), or C(stopped) + - When checking a port C(started) will ensure the port is open, C(stopped) will check that it is closed + - When checking for a file or a search string C(present) or C(started) will ensure that the file or string is present before continuing + choices: [ "present", "started", "stopped" ] default: "started" + path: + version_added: "1.4" + required: false + description: + - path to a file on the filesytem that must exist before continuing + search_regex: + version_added: "1.4" + required: false + description: + - with the path option can be used match a string in the file that must match before continuing. Defaults to a multiline regex. + notes: [] requirements: [] -author: Jeroen Hoekx +author: Jeroen Hoekx, John Jarvis ''' EXAMPLES = ''' + # wait 300 seconds for port 8000 to become open on the host, don't start checking for 10 seconds - wait_for: port=8000 delay=10" + +# wait until the file /tmp/foo is present before continuing +- wait_for: path=/tmp/foo + +# wait until the string "completed" is in the file /tmp/foo before continuing +- wait_for: path=/tmp/foo search_regex=completed + ''' def main(): @@ -78,8 +102,10 @@ def main(): timeout=dict(default=300), connect_timeout=dict(default=5), delay=dict(default=0), - port=dict(required=True), - state=dict(default='started', choices=['started', 'stopped']), + port=dict(default=None), + path=dict(default=None), + search_regex=dict(default=None), + state=dict(default='started', choices=['started', 'stopped', 'present']), ), ) @@ -89,16 +115,26 @@ def main(): timeout = int(params['timeout']) connect_timeout = int(params['connect_timeout']) delay = int(params['delay']) - port = int(params['port']) + if params['port']: + port = int(params['port']) + else: + port = None state = params['state'] - + path = params['path'] + search_regex = params['search_regex'] + + if port and path: + module.fail_json(msg="port and path parameter can not both be passed to wait_for") + if path and state == 'stopped': + module.fail_json(msg="state=stopped should only be used for checking a port in the wait_for module") + start = datetime.datetime.now() if delay: time.sleep(delay) if state == 'stopped': - ### first wait for the host to go down + ### first wait for the stop condition end = start + datetime.timedelta(seconds=timeout) while datetime.datetime.now() < end: @@ -115,27 +151,47 @@ def main(): elapsed = datetime.datetime.now() - start module.fail_json(msg="Timeout when waiting for %s:%s to stop." % (host, port), elapsed=elapsed.seconds) - elif state == 'started': - ### wait for the host to come up + elif state in ['started', 'present']: + ### wait for start condition end = start + datetime.timedelta(seconds=timeout) - while datetime.datetime.now() < end: - s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) - s.settimeout(connect_timeout) - try: - s.connect( (host, port) ) - s.shutdown(socket.SHUT_RDWR) - s.close() - break - except: - time.sleep(1) - pass + if path: + try: + with open(path) as f: + if search_regex: + if re.search(search_regex, f.read(), re.MULTILINE): + break + else: + time.sleep(1) + else: + break + except IOError: + time.sleep(1) + pass + elif port: + s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) + s.settimeout(connect_timeout) + try: + s.connect( (host, port) ) + s.shutdown(socket.SHUT_RDWR) + s.close() + break + except: + time.sleep(1) + pass else: elapsed = datetime.datetime.now() - start - module.fail_json(msg="Timeout when waiting for %s:%s" % (host, port), elapsed=elapsed.seconds) + if port: + module.fail_json(msg="Timeout when waiting for %s:%s" % (host, port), elapsed=elapsed.seconds) + elif path: + if search_regex: + module.fail_json(msg="Timeout when waiting for search string %s in %s" % (search_regex, path), elapsed=elapsed.seconds) + else: + module.fail_json(msg="Timeout when waiting for file %s" % (path), elapsed=elapsed.seconds) + elapsed = datetime.datetime.now() - start - module.exit_json(state=state, port=port, elapsed=elapsed.seconds) + module.exit_json(state=state, port=port, search_regex=search_regex, path=path, elapsed=elapsed.seconds) # this is magic, see lib/ansible/module_common.py #<>