Source code for pyngrok.process

import atexit
import logging
import os
import shlex
import subprocess
import threading
import time
from http import HTTPStatus
from urllib.request import Request, urlopen

import yaml

from pyngrok import conf, installer
from pyngrok.exception import PyngrokNgrokError, PyngrokSecurityError

__author__ = "Alex Laird"
__copyright__ = "Copyright 2021, Alex Laird"
__version__ = "5.1.0"

logger = logging.getLogger(__name__)
ngrok_logger = logging.getLogger("{}.ngrok".format(__name__))

_current_processes = {}


[docs]class NgrokProcess: """ An object containing information about the ``ngrok`` process. :var proc: The child process that is running ``ngrok``. :vartype proc: subprocess.Popen :var pyngrok_config: The ``pyngrok`` configuration to use with ``ngrok``. :vartype pyngrok_config: PyngrokConfig :var api_url: The API URL for the ``ngrok`` web interface. :vartype api_url: str :var logs: A list of the most recent logs from ``ngrok``, limited in size to ``max_logs``. :vartype logs: list[NgrokLog] :var startup_error: If ``ngrok`` startup fails, this will be the log of the failure. :vartype startup_error: str """ def __init__(self, proc, pyngrok_config): self.proc = proc self.pyngrok_config = pyngrok_config self.api_url = None self.logs = [] self.startup_error = None self._tunnel_started = False self._client_connected = False self._monitor_thread = None def __repr__(self): return "<NgrokProcess: \"{}\">".format(self.api_url) def __str__(self): # pragma: no cover return "NgrokProcess: \"{}\"".format(self.api_url) @staticmethod def _line_has_error(log): return log.lvl in ["ERROR", "CRITICAL"]
[docs] def _log_startup_line(self, line): """ Parse the given startup log line and use it to manage the startup state of the ``ngrok`` process. :param line: The line to be parsed and logged. :type line: str :return: The parsed log. :rtype: NgrokLog """ log = self._log_line(line) if log is None: return elif self._line_has_error(log): self.startup_error = log.err elif log.msg: # Log ngrok startup states as they come in if "starting web service" in log.msg and log.addr is not None: self.api_url = "http://{}".format(log.addr) elif "tunnel session started" in log.msg: self._tunnel_started = True elif "client session established" in log.msg: self._client_connected = True return log
[docs] def _log_line(self, line): """ Parse, log, and emit (if ``log_event_callback`` in :class:`~pyngrok.conf.PyngrokConfig` is registered) the given log line. :param line: The line to be processed. :type line: str :return: The parsed log. :rtype: NgrokLog """ log = NgrokLog(line) if log.line == "": return None ngrok_logger.log(getattr(logging, log.lvl), log.line) self.logs.append(log) if len(self.logs) > self.pyngrok_config.max_logs: self.logs.pop(0) if self.pyngrok_config.log_event_callback is not None: self.pyngrok_config.log_event_callback(log) return log
[docs] def healthy(self): """ Check whether the ``ngrok`` process has finished starting up and is in a running, healthy state. :return: ``True`` if the ``ngrok`` process is started, running, and healthy. :rtype: bool """ if self.api_url is None or \ not self._tunnel_started or \ not self._client_connected: return False if not self.api_url.lower().startswith("http"): raise PyngrokSecurityError("URL must start with \"http\": {}".format(self.api_url)) # Ensure the process is available for requests before registering it as healthy request = Request("{}/api/tunnels".format(self.api_url)) response = urlopen(request) if response.getcode() != HTTPStatus.OK: return False return self.proc.poll() is None
def _monitor_process(self): thread = threading.current_thread() thread.alive = True while thread.alive and self.proc.poll() is None: self._log_line(self.proc.stdout.readline()) self._monitor_thread = None
[docs] def start_monitor_thread(self): """ Start a thread that will monitor the ``ngrok`` process and its logs until it completes. If a monitor thread is already running, nothing will be done. """ if self._monitor_thread is None: logger.debug("Monitor thread will be started") self._monitor_thread = threading.Thread(target=self._monitor_process) self._monitor_thread.daemon = True self._monitor_thread.start()
[docs] def stop_monitor_thread(self): """ Set the monitor thread to stop monitoring the ``ngrok`` process after the next log event. This will not necessarily terminate the thread immediately, as the thread may currently be idle, rather it sets a flag on the thread telling it to terminate the next time it wakes up. This has no impact on the ``ngrok`` process itself, only ``pyngrok``'s monitor of the process and its logs. """ if self._monitor_thread is not None: logger.debug("Monitor thread will be stopped") self._monitor_thread.alive = False
[docs]class NgrokLog: """ An object containing a parsed log from the ``ngrok`` process. :var line: The raw, unparsed log line. :vartype line: str :var t: The log's ISO 8601 timestamp. :vartype t: str :var lvl: The log's level. :vartype lvl: str :var msg: The log's message. :vartype msg: str :var err: The log's error, if applicable. :vartype err: str :var addr: The URL, if ``obj`` is "web". :vartype addr: str """ def __init__(self, line): self.line = line.strip() self.t = None self.lvl = "NOTSET" self.msg = None self.err = None self.addr = None for i in shlex.split(self.line): if "=" not in i: continue key, value = i.split("=", 1) if key == "lvl": if not value: value = self.lvl value = value.upper() if value == "CRIT": value = "CRITICAL" elif value in ["ERR", "EROR"]: value = "ERROR" elif value == "WARN": value = "WARNING" if not hasattr(logging, value): value = self.lvl setattr(self, key, value) def __repr__(self): return "<NgrokLog: t={} lvl={} msg=\"{}\">".format(self.t, self.lvl, self.msg) def __str__(self): # pragma: no cover attrs = [attr for attr in dir(self) if not attr.startswith("_") and getattr(self, attr) is not None] attrs.remove("line") return " ".join("{}=\"{}\"".format(attr, getattr(self, attr)) for attr in attrs)
[docs]def set_auth_token(pyngrok_config, token): """ Set the ``ngrok`` auth token in the config file, enabling authenticated features (for instance, more concurrent tunnels, custom subdomains, etc.). :param pyngrok_config: The ``pyngrok`` configuration to use when interacting with the ``ngrok`` binary. :type pyngrok_config: PyngrokConfig :param token: The auth token to set. :type token: str """ start = [pyngrok_config.ngrok_path, "authtoken", token, "--log=stdout"] if pyngrok_config.config_path: logger.info("Updating authtoken for \"config_path\": {}".format(pyngrok_config.config_path)) start.append("--config={}".format(pyngrok_config.config_path)) else: logger.info( "Updating authtoken for default \"config_path\" of \"ngrok_path\": {}".format(pyngrok_config.ngrok_path)) result = subprocess.check_output(start) if "Authtoken saved" not in str(result): raise PyngrokNgrokError("An error occurred when saving the auth token: {}".format(result))
[docs]def is_process_running(ngrok_path): """ Check if the ``ngrok`` process is currently running. :param ngrok_path: The path to the ``ngrok`` binary. :type ngrok_path: str :return: ``True`` if ``ngrok`` is running from the given path. """ if ngrok_path in _current_processes: # Ensure the process is still running and hasn't been killed externally, otherwise cleanup if _current_processes[ngrok_path].proc.poll() is None: return True else: logger.debug( "Removing stale process for \"ngrok_path\" {}".format(ngrok_path)) _current_processes.pop(ngrok_path, None) return False
[docs]def get_process(pyngrok_config): """ Get the current ``ngrok`` process for the given config's ``ngrok_path``. If ``ngrok`` is not running, calling this method will first start a process with :class:`~pyngrok.conf.PyngrokConfig`. :param pyngrok_config: The ``pyngrok`` configuration to use when interacting with the ``ngrok`` binary. :type pyngrok_config: PyngrokConfig :return: The ``ngrok`` process. :rtype: NgrokProcess """ if is_process_running(pyngrok_config.ngrok_path): return _current_processes[pyngrok_config.ngrok_path] return _start_process(pyngrok_config)
[docs]def kill_process(ngrok_path): """ Terminate the ``ngrok`` processes, if running, for the given path. This method will not block, it will just issue a kill request. :param ngrok_path: The path to the ``ngrok`` binary. :type ngrok_path: str """ if is_process_running(ngrok_path): ngrok_process = _current_processes[ngrok_path] logger.info("Killing ngrok process: {}".format(ngrok_process.proc.pid)) try: ngrok_process.proc.kill() ngrok_process.proc.wait() except OSError as e: # pragma: no cover # If the process was already killed, nothing to do but cleanup state if e.errno != 3: raise e _current_processes.pop(ngrok_path, None) else: logger.debug("\"ngrok_path\" {} is not running a process".format(ngrok_path))
[docs]def run_process(ngrok_path, args): """ Start a blocking ``ngrok`` process with the binary at the given path and the passed args. This method is meant for invoking ``ngrok`` directly (for instance, from the command line) and is not necessarily compatible with non-blocking API methods. For that, use :func:`~pyngrok.process.get_process`. :param ngrok_path: The path to the ``ngrok`` binary. :type ngrok_path: str :param args: The args to pass to ``ngrok``. :type args: list[str] """ _validate_path(ngrok_path) start = [ngrok_path] + args subprocess.call(start)
[docs]def capture_run_process(ngrok_path, args): """ Start a blocking ``ngrok`` process with the binary at the given path and the passed args. When the process returns, so will this method, and the captured output from the process along with it. This method is meant for invoking ``ngrok`` directly (for instance, from the command line) and is not necessarily compatible with non-blocking API methods. For that, use :func:`~pyngrok.process.get_process`. :param ngrok_path: The path to the ``ngrok`` binary. :type ngrok_path: str :param args: The args to pass to ``ngrok``. :type args: list[str] :return: The output from the process. :rtype: str """ _validate_path(ngrok_path) start = [ngrok_path] + args output = subprocess.check_output(start) return output.decode("utf-8").strip()
[docs]def _validate_path(ngrok_path): """ Validate the given path exists, is a ``ngrok`` binary, and is ready to be started, otherwise raise a relevant exception. :param ngrok_path: The path to the ``ngrok`` binary. :type ngrok_path: str """ if not os.path.exists(ngrok_path): raise PyngrokNgrokError( "ngrok binary was not found. Be sure to call \"ngrok.install_ngrok()\" first for " "\"ngrok_path\": {}".format(ngrok_path)) if ngrok_path in _current_processes: raise PyngrokNgrokError("ngrok is already running for the \"ngrok_path\": {}".format(ngrok_path))
def _validate_config(config_path): with open(config_path, "r") as config_file: config = yaml.safe_load(config_file) if config is not None: installer.validate_config(config) def _terminate_process(process): if process is None: return try: process.terminate() except OSError: # pragma: no cover logger.debug("ngrok process already terminated: {}".format(process.pid))
[docs]def _start_process(pyngrok_config): """ Start a ``ngrok`` process with no tunnels. This will start the ``ngrok`` web interface, against which HTTP requests can be made to create, interact with, and destroy tunnels. :param pyngrok_config: The ``pyngrok`` configuration to use when interacting with the ``ngrok`` binary. :type pyngrok_config: PyngrokConfig :return: The ``ngrok`` process. :rtype: NgrokProcess """ if pyngrok_config.config_path is not None: config_path = pyngrok_config.config_path else: config_path = conf.DEFAULT_NGROK_CONFIG_PATH _validate_path(pyngrok_config.ngrok_path) _validate_config(config_path) start = [pyngrok_config.ngrok_path, "start", "--none", "--log=stdout"] if pyngrok_config.config_path: logger.info("Starting ngrok with config file: {}".format(pyngrok_config.config_path)) start.append("--config={}".format(pyngrok_config.config_path)) if pyngrok_config.auth_token: logger.info("Overriding default auth token") start.append("--authtoken={}".format(pyngrok_config.auth_token)) if pyngrok_config.region: logger.info("Starting ngrok in region: {}".format(pyngrok_config.region)) start.append("--region={}".format(pyngrok_config.region)) popen_kwargs = {"stdout": subprocess.PIPE, "universal_newlines": True} if os.name == "posix": popen_kwargs.update(start_new_session=pyngrok_config.start_new_session) elif pyngrok_config.start_new_session: logger.warning("Ignoring start_new_session=True, which requires POSIX") proc = subprocess.Popen(start, **popen_kwargs) atexit.register(_terminate_process, proc) logger.debug("ngrok process starting with PID: {}".format(proc.pid)) ngrok_process = NgrokProcess(proc, pyngrok_config) _current_processes[pyngrok_config.ngrok_path] = ngrok_process timeout = time.time() + pyngrok_config.startup_timeout while time.time() < timeout: line = proc.stdout.readline() ngrok_process._log_startup_line(line) if ngrok_process.healthy(): logger.debug("ngrok process has started with API URL: {}".format(ngrok_process.api_url)) ngrok_process.startup_error = None if pyngrok_config.monitor_thread: ngrok_process.start_monitor_thread() break elif ngrok_process.proc.poll() is not None: break if not ngrok_process.healthy(): # If the process did not come up in a healthy state, clean up the state kill_process(pyngrok_config.ngrok_path) if ngrok_process.startup_error is not None: raise PyngrokNgrokError("The ngrok process errored on start: {}.".format(ngrok_process.startup_error), ngrok_process.logs, ngrok_process.startup_error) else: raise PyngrokNgrokError("The ngrok process was unable to start.", ngrok_process.logs) return ngrok_process