X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=lttng_ivc%2Futils%2Futils.py;h=3efc2b1f8cd5f06906fb57106f919f62491a64d3;hb=ac21c1f5e0a2dcdb21abc4a7d8416dd78344912c;hp=b2de919301768f1748489b1222d1336ae77d9047;hpb=29cf55b3540b1c31f1718035f36cc7a5a3dc671a;p=deliverable%2Flttng-ivc.git diff --git a/lttng_ivc/utils/utils.py b/lttng_ivc/utils/utils.py index b2de919..3efc2b1 100644 --- a/lttng_ivc/utils/utils.py +++ b/lttng_ivc/utils/utils.py @@ -1,5 +1,12 @@ import signal import hashlib +import os +import time +import socket + +from lxml import etree +from contextlib import closing + def line_count(file_path): line_count = 0 @@ -17,16 +24,158 @@ def sha256_checksum(filename, block_size=65536): return sha256.hexdigest() +# TODO: timeout as a parameter or Settings +# TODO: Custom exception +def wait_for_file(path): + i = 0 + timeout = 60 + while not os.path.exists(path): + time.sleep(1) + i = i + 1 + if i > timeout: + raise Exception("File still does not exists. Timeout expired") + + +# TODO: find better exception +def create_empty_file(path): + if os.path.exists(path): + raise Exception("Path already exist") + open(path, 'w').close() + + def __dummy_sigusr1_handler(): pass -def sessiond_spawn(runtime): +def sessiond_spawn(runtime, opt_args=""): + agent_port = find_free_port() previous_handler = signal.signal(signal.SIGUSR1, __dummy_sigusr1_handler) - sessiond = runtime.spawn_subprocess("lttng-sessiond -vvv -S") + cmd = "lttng-sessiond -vvv --verbose-consumer -S --agent-tcp-port {}".format(agent_port) + cmd = " ".join([cmd, opt_args]) + sessiond = runtime.spawn_subprocess(cmd) signal.sigtimedwait({signal.SIGUSR1}, 60) previous_handler = signal.signal(signal.SIGUSR1, previous_handler) return sessiond +def relayd_spawn(runtime, url="localhost"): + """ + Return a tuple (relayd_uuid, ctrl_port, data_port, live_port) + """ + ports = find_multiple_free_port(3) + data_port = ports.pop() + ctrl_port = ports.pop() + live_port = ports.pop() + + base_cmd = "lttng-relayd -vvv" + data_string = "-D tcp://{}:{}".format(url, data_port) + ctrl_string = "-C tcp://{}:{}".format(url, ctrl_port) + live_string = "-L tcp://{}:{}".format(url, live_port) + + cmd = " ".join([base_cmd, data_string, ctrl_string, live_string]) + relayd = runtime.spawn_subprocess(cmd) + + # Synchronization based on verbosity since no -S is available for + # lttng-relayd yet. + log_path = runtime.get_subprocess_stderr_path(relayd) + + # TODO: Move to settings. + ready_cue = "Listener accepting live viewers connections" + # TODO: Move to settings. + timeout = 60 + ready = False + for i in range(timeout): + if file_contains(log_path, ready_cue): + ready = True + break + time.sleep(1) + + if not ready: + # Cleanup is performed by runtime + raise Exception("Relayd readyness timeout expired") + + return (relayd, ctrl_port, data_port, live_port) + + +def find_free_port(): + # There is no guarantee that the port will be free at runtime but should be + # good enough + with closing(socket.socket(socket.AF_INET, socket.SOCK_STREAM)) as s: + s.bind(('', 0)) + return s.getsockname()[1] + + +def find_multiple_free_port(number): + """ + Return a list of supposedly free port + """ + assert(number >= 0) + ports = [] + while(len(ports) != number): + port = find_free_port() + if port in ports: + continue + ports.append(port) + return ports + + +def file_contains(file_path, list_of_string): + with open(file_path, 'r') as f: + for line in f: + for s in list_of_string: + if s in line: + return True + + +def find_dir(root, name): + """ + Returns the absolute path or None. + """ + abs_path = None + for base, dirs, files in os.walk(root): + for tmp in dirs: + if tmp.endswith(name): + abs_path = os.path.abspath(os.path.join(base, tmp)) + return abs_path + + +def find_file(root, name): + """ + Returns the absolute path or None. + """ + abs_path = None + for base, dirs, files in os.walk(root): + for tmp in files: + if tmp.endswith(name): + abs_path = os.path.abspath(os.path.join(base, tmp)) + return abs_path + + +def validate(xml_path, xsd_path): + + xmlschema_doc = etree.parse(xsd_path) + xmlschema = etree.XMLSchema(xmlschema_doc) + + xml_doc = etree.parse(xml_path) + result = xmlschema.validate(xml_doc) + + return result + +def xpath_query(xml_file, xpath): + """ + Return a list of xml node corresponding to the xpath. The list can be of lenght + zero. + """ + with open(xml_file, 'r') as f: + tree = etree.parse(f) + root = tree.getroot() + # Remove all namespace + # https://stackoverflow.com/questions/18159221/remove-namespace-and-prefix-from-xml-in-python-using-lxml + for elem in root.getiterator(): + if not hasattr(elem.tag, 'find'): + continue + i = elem.tag.find('}') + if i >= 0: + elem.tag = elem.tag[i+1:] + return root.xpath(xpath)