feat: Add new gcloud commands, API clients, and third-party libraries across various services.

gcloud auth application-default login/google-cloud-sdk/lib/third_party/portpicker/LICENSE

@@ -0,0 +1,176 @@
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gcloud auth application-default login/google-cloud-sdk/lib/third_party/portpicker/__init__.py

@@ -0,0 +1,499 @@
+#!/usr/bin/python3
+#
+# Copyright 2007 Google Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+"""Pure python code for finding unused ports on a host.
+
+This module provides a pick_unused_port() function.
+It can also be called via the command line for use in shell scripts.
+When called from the command line, it takes one optional argument, which,
+if given, is sent to portserver instead of portpicker's PID.
+To reserve a port for the lifetime of a bash script, use $BASHPID as this
+argument.
+
+There is a race condition between picking a port and your application code
+binding to it.  The use of a port server to prevent that is recommended on
+loaded test hosts running many tests at a time.
+
+If your code can accept a bound socket as input rather than being handed a
+port number consider using socket.bind(('localhost', 0)) to bind to an
+available port without a race condition rather than using this library.
+
+Typical usage:
+  test_port = portpicker.pick_unused_port()
+"""
+
+# pylint: disable=consider-using-f-string
+# Some people still use this on old Pythons despite our test matrix and
+# supported versions.  Be kind for now, until it gets in our way.
+from __future__ import print_function
+
+import logging
+import os
+import random
+import socket
+import sys
+import time
+
+_winapi = None  # pylint: disable=invalid-name
+if sys.platform == 'win32':
+    try:
+        import _winapi
+    except ImportError:
+        _winapi = None
+
+# The legacy Bind, IsPortFree, etc. names are not exported.
+__all__ = ('bind', 'is_port_free', 'pick_unused_port', 'return_port',
+           'add_reserved_port', 'get_port_from_port_server')
+
+_PROTOS = [(socket.SOCK_STREAM, socket.IPPROTO_TCP),
+           (socket.SOCK_DGRAM, socket.IPPROTO_UDP)]
+
+
+# Ports that are currently available to be given out.
+_free_ports = set()
+
+# Ports that are reserved or from the portserver that may be returned.
+_owned_ports = set()
+
+# Ports that we chose randomly that may be returned.
+_random_ports = set()
+
+
+class NoFreePortFoundError(Exception):
+    """Exception indicating that no free port could be found."""
+
+
+def add_reserved_port(port):
+    """Add a port that was acquired by means other than the port server."""
+    _free_ports.add(port)
+
+
+def return_port(port):
+    """Return a port that is no longer being used so it can be reused."""
+    if port in _random_ports:
+        _random_ports.remove(port)
+    elif port in _owned_ports:
+        _owned_ports.remove(port)
+        _free_ports.add(port)
+    elif port in _free_ports:
+        logging.info("Returning a port that was already returned: %s", port)
+    else:
+        logging.info("Returning a port that wasn't given by portpicker: %s",
+                     port)
+
+
+def bind(port, socket_type, socket_proto):
+    """Try to bind to a socket of the specified type, protocol, and port.
+
+    This is primarily a helper function for PickUnusedPort, used to see
+    if a particular port number is available.
+
+    For the port to be considered available, the kernel must support at least
+    one of (IPv6, IPv4), and the port must be available on each supported
+    family.
+
+    Args:
+      port: The port number to bind to, or 0 to have the OS pick a free port.
+      socket_type: The type of the socket (ex: socket.SOCK_STREAM).
+      socket_proto: The protocol of the socket (ex: socket.IPPROTO_TCP).
+
+    Returns:
+      The port number on success or None on failure.
+    """
+    return _bind(port, socket_type, socket_proto)
+
+
+def _bind(port, socket_type, socket_proto, return_socket=None,
+          return_family=socket.AF_INET6):
+    """Internal implementation of bind.
+
+    Args:
+      port, socket_type, socket_proto: see bind().
+      return_socket: If supplied, a list that we will append an open bound
+          reuseaddr socket on the port in question to.
+      return_family: The socket family to return in return_socket.
+
+    Returns:
+      The port number on success or None on failure.
+    """
+    # Our return family must come last when returning a bound socket
+    # as we cannot keep it bound while testing a bind on the other
+    # family with many network stack configurations.
+    if return_socket is None or return_family == socket.AF_INET:
+        socket_families = (socket.AF_INET6, socket.AF_INET)
+    elif return_family == socket.AF_INET6:
+        socket_families = (socket.AF_INET, socket.AF_INET6)
+    else:
+        raise ValueError('unknown return_family %s' % return_family)
+    got_socket = False
+    for family in socket_families:
+        try:
+            sock = socket.socket(family, socket_type, socket_proto)
+            got_socket = True
+        except socket.error:
+            continue
+        try:
+            sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+            sock.bind(('', port))
+            if socket_type == socket.SOCK_STREAM:
+                sock.listen(1)
+            port = sock.getsockname()[1]
+        except socket.error:
+            return None
+        finally:
+            if return_socket is None or family != return_family:
+                try:
+                    # Adding this resolved 1 in ~500 flakiness that we were
+                    # seeing from an integration test framework managing a set
+                    # of ports with is_port_free().  close() doesn't move the
+                    # TCP state machine along quickly.
+                    sock.shutdown(socket.SHUT_RDWR)
+                except OSError:
+                    pass
+                sock.close()
+        if return_socket is not None and family == return_family:
+            return_socket.append(sock)
+            break  # Final iteration due to pre-loop logic; don't close.
+    return port if got_socket else None
+
+
+def is_port_free(port):
+    """Check if specified port is free.
+
+    Args:
+      port: integer, port to check
+
+    Returns:
+      bool, whether port is free to use for both TCP and UDP.
+    """
+    return _is_port_free(port)
+
+
+def _is_port_free(port, return_sockets=None):
+    """Internal implementation of is_port_free.
+
+    Args:
+      port: integer, port to check
+      return_sockets: If supplied, a list that we will append open bound
+        sockets on the port in question to rather than closing them.
+
+    Returns:
+      bool, whether port is free to use for both TCP and UDP.
+    """
+    return (_bind(port, *_PROTOS[0], return_socket=return_sockets) and
+            _bind(port, *_PROTOS[1], return_socket=return_sockets))
+
+
+def pick_unused_port(pid=None, portserver_address=None):
+    """Picks an unused port and reserves it for use by a given process id.
+
+    Args:
+      pid: PID to tell the portserver to associate the reservation with. If
+        None, the current process's PID is used.
+      portserver_address: The address (path) of a unix domain socket
+        with which to connect to a portserver, a leading '@'
+        character indicates an address in the "abstract namespace".  OR
+        On systems without socket.AF_UNIX, this is an AF_INET address.
+        If None, or no port is returned by the portserver at the provided
+        address, the environment will be checked for a PORTSERVER_ADDRESS
+        variable.  If that is not set, no port server will be used.
+
+    If no portserver is used, no pid based reservation is managed by any
+    central authority. Race conditions and duplicate assignments may occur.
+
+    Returns:
+      A port number that is unused on both TCP and UDP.
+
+    Raises:
+      NoFreePortFoundError: No free port could be found.
+    """
+    return _pick_unused_port(pid, portserver_address)
+
+
+def _pick_unused_port(pid=None, portserver_address=None,
+                     noserver_bind_timeout=0):
+    """Internal implementation of pick_unused_port.
+
+    Args:
+      pid, portserver_address: See pick_unused_port().
+      noserver_bind_timeout: If no portserver was used, this is the number of
+        seconds we will attempt to keep a child process around with the ports
+        returned open and bound SO_REUSEADDR style to help avoid race condition
+        port reuse. A non-zero value attempts os.fork(). Do not use it in a
+        multithreaded process.
+    """
+    try:  # Instead of `if _free_ports:` to handle the race condition.
+        port = _free_ports.pop()
+    except KeyError:
+        pass
+    else:
+        _owned_ports.add(port)
+        return port
+    # Provide access to the portserver on an opt-in basis.
+    if portserver_address:
+        port = get_port_from_port_server(portserver_address, pid=pid)
+        if port:
+            return port
+    if 'PORTSERVER_ADDRESS' in os.environ:
+        port = get_port_from_port_server(os.environ['PORTSERVER_ADDRESS'],
+                                         pid=pid)
+        if port:
+            return port
+    return _pick_unused_port_without_server(bind_timeout=noserver_bind_timeout)
+
+
+def _spawn_bound_port_holding_daemon(port, bound_sockets, timeout):
+    """If possible, fork()s a daemon process to hold bound_sockets open.
+
+    Emits a warning to stderr if it cannot.
+
+    Args:
+      port: The port number the sockets are bound to (informational).
+      bound_sockets: The list of bound sockets our child process will hold
+          open. If the list is empty, no action is taken.
+      timeout: A positive number of seconds the child should sleep for before
+          closing the sockets and exiting.
+    """
+    if bound_sockets and timeout > 0:
+        try:
+            fork_pid = os.fork()  # This concept only works on POSIX.
+        except Exception as err:  # pylint: disable=broad-except
+            print('WARNING: Cannot timeout unbinding close of port', port,
+                  ' closing on exit. -', err, file=sys.stderr)
+        else:
+            if fork_pid == 0:
+                # This child process inherits and holds bound_sockets open
+                # for bind_timeout seconds.
+                try:
+                    # Close the stdio fds as may be connected to
+                    # a pipe that will cause a grandparent process
+                    # to wait on before returning. (cl/427587550)
+                    os.close(sys.stdin.fileno())
+                    os.close(sys.stdout.fileno())
+                    os.close(sys.stderr.fileno())
+                    time.sleep(timeout)
+                    for held_socket in bound_sockets:
+                        held_socket.close()
+                finally:
+                    os._exit(0)
+
+
+def _pick_unused_port_without_server(bind_timeout=0):
+    """Pick an available network port without the help of a port server.
+
+    This code ensures that the port is available on both TCP and UDP.
+
+    This function is an implementation detail of PickUnusedPort(), and
+    should not be called by code outside of this module.
+
+    Args:
+      bind_timeout: number of seconds to attempt to keep a child process
+          process around bound SO_REUSEADDR style to the port. If we cannot
+          do that we emit a warning to stderr.
+
+    Returns:
+      A port number that is unused on both TCP and UDP.
+
+    Raises:
+      NoFreePortFoundError: No free port could be found.
+    """
+    # Next, try a few times to get an OS-assigned port.
+    # Ambrose discovered that on the 2.6 kernel, calling Bind() on UDP socket
+    # returns the same port over and over. So always try TCP first.
+    port = None
+    bound_sockets = [] if bind_timeout > 0 else None
+    for _ in range(10):
+        # Ask the OS for an unused port.
+        port = _bind(0, socket.SOCK_STREAM, socket.IPPROTO_TCP, bound_sockets)
+        # Check if this port is unused on the other protocol.
+        if (port and port not in _random_ports and
+            _bind(port, socket.SOCK_DGRAM, socket.IPPROTO_UDP, bound_sockets)):
+            _random_ports.add(port)
+            _spawn_bound_port_holding_daemon(port, bound_sockets, bind_timeout)
+            return port
+        if bound_sockets:
+            for held_socket in bound_sockets:
+                held_socket.close()
+            del bound_sockets[:]
+
+    # Try random ports as a last resort.
+    rng = random.Random()
+    for _ in range(10):
+        port = int(rng.randrange(15000, 25000))
+        if port not in _random_ports:
+            if _is_port_free(port, bound_sockets):
+                _random_ports.add(port)
+                _spawn_bound_port_holding_daemon(
+                        port, bound_sockets, bind_timeout)
+                return port
+            if bound_sockets:
+                for held_socket in bound_sockets:
+                    held_socket.close()
+                del bound_sockets[:]
+
+    # Give up.
+    raise NoFreePortFoundError()
+
+
+def _posix_get_port_from_port_server(portserver_address, pid):
+    # An AF_UNIX address may start with a zero byte, in which case it is in the
+    # "abstract namespace", and doesn't have any filesystem representation.
+    # See 'man 7 unix' for details.
+    # The convention is to write '@' in the address to represent this zero byte.
+    if portserver_address[0] == '@':
+        portserver_address = '\0' + portserver_address[1:]
+
+    try:
+        # Create socket.
+        if hasattr(socket, 'AF_UNIX'):
+            sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+        else:
+            # fallback to AF_INET if this is not unix
+            sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        try:
+            # Connect to portserver.
+            sock.connect(portserver_address)
+
+            # Write request.
+            sock.sendall(('%d\n' % pid).encode('ascii'))
+
+            # Read response.
+            # 1K should be ample buffer space.
+            return sock.recv(1024)
+        finally:
+            sock.close()
+    except socket.error as error:
+        print('Socket error when connecting to portserver:', error,
+              file=sys.stderr)
+        return None
+
+
+def _windows_get_port_from_port_server(portserver_address, pid):
+    if portserver_address[0] == '@':
+        portserver_address = '\\\\.\\pipe\\' + portserver_address[1:]
+
+    try:
+        handle = _winapi.CreateFile(
+            portserver_address,
+            _winapi.GENERIC_READ | _winapi.GENERIC_WRITE,
+            0,
+            0,
+            _winapi.OPEN_EXISTING,
+            0,
+            0)
+
+        _winapi.WriteFile(handle, ('%d\n' % pid).encode('ascii'))
+        data, _ = _winapi.ReadFile(handle, 6, 0)
+        return data
+    except FileNotFoundError as error:
+        print('File error when connecting to portserver:', error,
+              file=sys.stderr)
+        return None
+
+
+def get_port_from_port_server(portserver_address, pid=None):
+    """Request a free a port from a system-wide portserver.
+
+    This follows a very simple portserver protocol:
+    The request consists of our pid (in ASCII) followed by a newline.
+    The response is a port number and a newline, 0 on failure.
+
+    This function is an implementation detail of pick_unused_port().
+    It should not normally be called by code outside of this module.
+
+    Args:
+      portserver_address: The address (path) of a unix domain socket
+        with which to connect to the portserver.  A leading '@'
+        character indicates an address in the "abstract namespace."
+        On systems without socket.AF_UNIX, this is an AF_INET address.
+      pid: The PID to tell the portserver to associate the reservation with.
+        If None, the current process's PID is used.
+
+    Returns:
+      The port number on success or None on failure.
+    """
+    if not portserver_address:
+        return None
+
+    if pid is None:
+        pid = os.getpid()
+
+    if _winapi:
+        buf = _windows_get_port_from_port_server(portserver_address, pid)
+    else:
+        buf = _posix_get_port_from_port_server(portserver_address, pid)
+
+    if buf is None:
+        return None
+
+    try:
+        port = int(buf.split(b'\n')[0])
+    except ValueError:
+        print('Portserver failed to find a port.', file=sys.stderr)
+        return None
+    _owned_ports.add(port)
+    return port
+
+
+# Legacy APIs.
+# pylint: disable=invalid-name
+Bind = bind
+GetPortFromPortServer = get_port_from_port_server
+IsPortFree = is_port_free
+PickUnusedPort = pick_unused_port
+# pylint: enable=invalid-name
+
+
+def main(argv):
+    """If passed an arg, treat it as a PID, otherwise we use getppid().
+
+    A second optional argument can be a bind timeout in seconds that will be
+    used ONLY if no portserver is found. We attempt to leave a process around
+    holding the port open and bound with SO_REUSEADDR set for timeout seconds.
+    If the timeout bind was not possible, a warning is emitted to stderr.
+
+      #!/bin/bash
+      port="$(python -m portpicker $$ 1.23)"
+      test_my_server "$port"
+
+    This will pick a port for your script's PID and assign it to $port, if no
+    portserver was used, it attempts to keep a socket bound to $port for 1.23
+    seconds after the portpicker process has exited. This is a convenient hack
+    to attempt to prevent port reallocation during scripts outside of
+    portserver managed environments.
+
+    Older versions of the portpicker CLI ignore everything beyond the first arg.
+    Older versions also used getpid() instead of getppid(), so script users are
+    strongly encouraged to be explicit and pass $$ or your languages equivalent
+    to associate the port with the PID of the controlling process.
+    """
+    # Our command line is trivial so I avoid an argparse import. If we ever
+    # grow more than 1-2 args, switch to a using argparse.
+    if '-h' in argv or '--help' in argv:
+        print(argv[0], 'usage:\n')
+        import inspect
+        print(inspect.getdoc(main))
+        sys.exit(1)
+    pid=int(argv[1]) if len(argv) > 1 else os.getppid()
+    bind_timeout=float(argv[2]) if len(argv) > 2 else 0
+    port = _pick_unused_port(pid=pid, noserver_bind_timeout=bind_timeout)
+    if not port:
+        sys.exit(1)
+    print(port)
+
+
+if __name__ == '__main__':
+    main(sys.argv)