diff mbox

[v6,01/10] qemu.py: Pylint/style fixes

Message ID 20170818142613.32394-2-ldoktor@redhat.com (mailing list archive)
State New, archived
Headers show

Commit Message

Lukáš Doktor Aug. 18, 2017, 2:26 p.m. UTC 
No actual code changes, just several pylint/style fixes and docstring
clarifications.

Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 scripts/qemu.py | 73 +++++++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 55 insertions(+), 18 deletions(-)

Comments

Cleber Rosa Aug. 24, 2017, 10:38 p.m. UTC | #1 
On 08/18/2017 10:26 AM, Lukáš Doktor wrote:
> No actual code changes, just several pylint/style fixes and docstring
> clarifications.
> 
> Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>  scripts/qemu.py | 73 +++++++++++++++++++++++++++++++++++++++++++--------------
>  1 file changed, 55 insertions(+), 18 deletions(-)
> 
> diff --git a/scripts/qemu.py b/scripts/qemu.py
> index 880e3e8..dd679f1 100644
> --- a/scripts/qemu.py
> +++ b/scripts/qemu.py
> @@ -23,8 +23,22 @@ import qmp.qmp
>  class QEMUMachine(object):
>      '''A QEMU VM'''
>  
> -    def __init__(self, binary, args=[], wrapper=[], name=None, test_dir="/var/tmp",
> -                 monitor_address=None, socket_scm_helper=None, debug=False):
> +    def __init__(self, binary, args=[], wrapper=[], name=None,
> +                 test_dir="/var/tmp", monitor_address=None,
> +                 socket_scm_helper=None, debug=False):
> +        '''
> +        Initialize a QEMUMachine
> +
> +        @param binary: path to the qemu binary
> +        @param args: list of extra arguments
> +        @param wrapper: list of arguments used as prefix to qemu binary
> +        @param name: prefix for socket and log file names (default: qemu-PID)
> +        @param test_dir: where to create socket and log file
> +        @param monitor_address: address for QMP monitor
> +        @param socket_scm_helper: helper program, required for send_fd_scm()"
> +        @param debug: enable debug mode
> +        @note: Qemu process is not started until launch() is used.
> +        '''
>          if name is None:
>              name = "qemu-%d" % os.getpid()
>          if monitor_address is None:
> @@ -33,12 +47,13 @@ class QEMUMachine(object):
>          self._qemu_log_path = os.path.join(test_dir, name + ".log")
>          self._popen = None
>          self._binary = binary
> -        self._args = list(args) # Force copy args in case we modify them
> +        self._args = list(args)     # Force copy args in case we modify them
>          self._wrapper = wrapper
>          self._events = []
>          self._iolog = None
>          self._socket_scm_helper = socket_scm_helper
>          self._debug = debug
> +        self._qmp = None
>  
>      # This can be used to add an unused monitor instance.
>      def add_monitor_telnet(self, ip, port):
> @@ -64,16 +79,16 @@ class QEMUMachine(object):
>          if self._socket_scm_helper is None:
>              print >>sys.stderr, "No path to socket_scm_helper set"
>              return -1
> -        if os.path.exists(self._socket_scm_helper) == False:
> +        if not os.path.exists(self._socket_scm_helper):
>              print >>sys.stderr, "%s does not exist" % self._socket_scm_helper
>              return -1
>          fd_param = ["%s" % self._socket_scm_helper,
>                      "%d" % self._qmp.get_sock_fd(),
>                      "%s" % fd_file_path]
>          devnull = open('/dev/null', 'rb')
> -        p = subprocess.Popen(fd_param, stdin=devnull, stdout=sys.stdout,
> -                             stderr=sys.stderr)
> -        return p.wait()
> +        proc = subprocess.Popen(fd_param, stdin=devnull, stdout=sys.stdout,
> +                                stderr=sys.stderr)
> +        return proc.wait()
>  
>      @staticmethod
>      def _remove_if_exists(path):
> @@ -99,8 +114,8 @@ class QEMUMachine(object):
>          return self._popen.pid
>  
>      def _load_io_log(self):
> -        with open(self._qemu_log_path, "r") as fh:
> -            self._iolog = fh.read()
> +        with open(self._qemu_log_path, "r") as iolog:
> +            self._iolog = iolog.read()
>  
>      def _base_args(self):
>          if isinstance(self._monitor_address, tuple):
> @@ -114,7 +129,8 @@ class QEMUMachine(object):
>                  '-display', 'none', '-vga', 'none']
>  
>      def _pre_launch(self):
> -        self._qmp = qmp.qmp.QEMUMonitorProtocol(self._monitor_address, server=True,
> +        self._qmp = qmp.qmp.QEMUMonitorProtocol(self._monitor_address,
> +                                                server=True,
>                                                  debug=self._debug)
>  
>      def _post_launch(self):
> @@ -131,9 +147,11 @@ class QEMUMachine(object):
>          qemulog = open(self._qemu_log_path, 'wb')
>          try:
>              self._pre_launch()
> -            args = self._wrapper + [self._binary] + self._base_args() + self._args
> +            args = (self._wrapper + [self._binary] + self._base_args() +
> +                    self._args)
>              self._popen = subprocess.Popen(args, stdin=devnull, stdout=qemulog,
> -                                           stderr=subprocess.STDOUT, shell=False)
> +                                           stderr=subprocess.STDOUT,
> +                                           shell=False)
>              self._post_launch()
>          except:
>              if self.is_running():
> @@ -154,23 +172,30 @@ class QEMUMachine(object):
>  
>              exitcode = self._popen.wait()
>              if exitcode < 0:
> -                sys.stderr.write('qemu received signal %i: %s\n' % (-exitcode, ' '.join(self._args)))
> +                sys.stderr.write('qemu received signal %i: %s\n'
> +                                 % (-exitcode, ' '.join(self._args)))
>              self._load_io_log()
>              self._post_shutdown()
>  
>      underscore_to_dash = string.maketrans('_', '-')
> +
>      def qmp(self, cmd, conv_keys=True, **args):
> -        '''Invoke a QMP command and return the result dict'''
> +        '''Invoke a QMP command and return the response dict'''
>          qmp_args = dict()
> -        for k in args.keys():
> +        for key in args.keys():
>              if conv_keys:
> -                qmp_args[k.translate(self.underscore_to_dash)] = args[k]
> +                qmp_args[key.translate(self.underscore_to_dash)] = args[key]
>              else:
> -                qmp_args[k] = args[k]
> +                qmp_args[key] = args[key]
>  
>          return self._qmp.cmd(cmd, args=qmp_args)
>  
>      def command(self, cmd, conv_keys=True, **args):
> +        '''
> +        Invoke a QMP command.
> +        On success return the response dict.
> +        On failure raise an exception.
> +        '''
>          reply = self.qmp(cmd, conv_keys, **args)
>          if reply is None:
>              raise Exception("Monitor is closed")
> @@ -193,7 +218,15 @@ class QEMUMachine(object):
>          return events
>  
>      def event_wait(self, name, timeout=60.0, match=None):
> -        # Test if 'match' is a recursive subset of 'event'
> +        '''
> +        Wait for specified timeout on named event in QMP; optionally filter
> +        results by match.
> +
> +        The 'match' is checked to be a recursive subset of the 'event'; skips
> +        branch processing on match's value None
> +           {"foo": {"bar": 1}} matches {"foo": None}
> +           {"foo": {"bar": 1}} does not matches {"foo": {"baz": None}}
> +        '''
>          def event_match(event, match=None):
>              if match is None:
>                  return True
> @@ -226,4 +259,8 @@ class QEMUMachine(object):
>          return None
>  
>      def get_log(self):
> +        '''
> +        After self.shutdown or failed qemu execution, this returns the output
> +        of the qemu process.
> +        '''
>          return self._iolog
> 

Reviewed-by: Cleber Rosa <crosa@redhat.com>
diff mbox

Patch

diff --git a/scripts/qemu.py b/scripts/qemu.py
index 880e3e8..dd679f1 100644
--- a/scripts/qemu.py
+++ b/scripts/qemu.py
@@ -23,8 +23,22 @@  import qmp.qmp
 class QEMUMachine(object):
     '''A QEMU VM'''
 
-    def __init__(self, binary, args=[], wrapper=[], name=None, test_dir="/var/tmp",
-                 monitor_address=None, socket_scm_helper=None, debug=False):
+    def __init__(self, binary, args=[], wrapper=[], name=None,
+                 test_dir="/var/tmp", monitor_address=None,
+                 socket_scm_helper=None, debug=False):
+        '''
+        Initialize a QEMUMachine
+
+        @param binary: path to the qemu binary
+        @param args: list of extra arguments
+        @param wrapper: list of arguments used as prefix to qemu binary
+        @param name: prefix for socket and log file names (default: qemu-PID)
+        @param test_dir: where to create socket and log file
+        @param monitor_address: address for QMP monitor
+        @param socket_scm_helper: helper program, required for send_fd_scm()"
+        @param debug: enable debug mode
+        @note: Qemu process is not started until launch() is used.
+        '''
         if name is None:
             name = "qemu-%d" % os.getpid()
         if monitor_address is None:
@@ -33,12 +47,13 @@  class QEMUMachine(object):
         self._qemu_log_path = os.path.join(test_dir, name + ".log")
         self._popen = None
         self._binary = binary
-        self._args = list(args) # Force copy args in case we modify them
+        self._args = list(args)     # Force copy args in case we modify them
         self._wrapper = wrapper
         self._events = []
         self._iolog = None
         self._socket_scm_helper = socket_scm_helper
         self._debug = debug
+        self._qmp = None
 
     # This can be used to add an unused monitor instance.
     def add_monitor_telnet(self, ip, port):
@@ -64,16 +79,16 @@  class QEMUMachine(object):
         if self._socket_scm_helper is None:
             print >>sys.stderr, "No path to socket_scm_helper set"
             return -1
-        if os.path.exists(self._socket_scm_helper) == False:
+        if not os.path.exists(self._socket_scm_helper):
             print >>sys.stderr, "%s does not exist" % self._socket_scm_helper
             return -1
         fd_param = ["%s" % self._socket_scm_helper,
                     "%d" % self._qmp.get_sock_fd(),
                     "%s" % fd_file_path]
         devnull = open('/dev/null', 'rb')
-        p = subprocess.Popen(fd_param, stdin=devnull, stdout=sys.stdout,
-                             stderr=sys.stderr)
-        return p.wait()
+        proc = subprocess.Popen(fd_param, stdin=devnull, stdout=sys.stdout,
+                                stderr=sys.stderr)
+        return proc.wait()
 
     @staticmethod
     def _remove_if_exists(path):
@@ -99,8 +114,8 @@  class QEMUMachine(object):
         return self._popen.pid
 
     def _load_io_log(self):
-        with open(self._qemu_log_path, "r") as fh:
-            self._iolog = fh.read()
+        with open(self._qemu_log_path, "r") as iolog:
+            self._iolog = iolog.read()
 
     def _base_args(self):
         if isinstance(self._monitor_address, tuple):
@@ -114,7 +129,8 @@  class QEMUMachine(object):
                 '-display', 'none', '-vga', 'none']
 
     def _pre_launch(self):
-        self._qmp = qmp.qmp.QEMUMonitorProtocol(self._monitor_address, server=True,
+        self._qmp = qmp.qmp.QEMUMonitorProtocol(self._monitor_address,
+                                                server=True,
                                                 debug=self._debug)
 
     def _post_launch(self):
@@ -131,9 +147,11 @@  class QEMUMachine(object):
         qemulog = open(self._qemu_log_path, 'wb')
         try:
             self._pre_launch()
-            args = self._wrapper + [self._binary] + self._base_args() + self._args
+            args = (self._wrapper + [self._binary] + self._base_args() +
+                    self._args)
             self._popen = subprocess.Popen(args, stdin=devnull, stdout=qemulog,
-                                           stderr=subprocess.STDOUT, shell=False)
+                                           stderr=subprocess.STDOUT,
+                                           shell=False)
             self._post_launch()
         except:
             if self.is_running():
@@ -154,23 +172,30 @@  class QEMUMachine(object):
 
             exitcode = self._popen.wait()
             if exitcode < 0:
-                sys.stderr.write('qemu received signal %i: %s\n' % (-exitcode, ' '.join(self._args)))
+                sys.stderr.write('qemu received signal %i: %s\n'
+                                 % (-exitcode, ' '.join(self._args)))
             self._load_io_log()
             self._post_shutdown()
 
     underscore_to_dash = string.maketrans('_', '-')
+
     def qmp(self, cmd, conv_keys=True, **args):
-        '''Invoke a QMP command and return the result dict'''
+        '''Invoke a QMP command and return the response dict'''
         qmp_args = dict()
-        for k in args.keys():
+        for key in args.keys():
             if conv_keys:
-                qmp_args[k.translate(self.underscore_to_dash)] = args[k]
+                qmp_args[key.translate(self.underscore_to_dash)] = args[key]
             else:
-                qmp_args[k] = args[k]
+                qmp_args[key] = args[key]
 
         return self._qmp.cmd(cmd, args=qmp_args)
 
     def command(self, cmd, conv_keys=True, **args):
+        '''
+        Invoke a QMP command.
+        On success return the response dict.
+        On failure raise an exception.
+        '''
         reply = self.qmp(cmd, conv_keys, **args)
         if reply is None:
             raise Exception("Monitor is closed")
@@ -193,7 +218,15 @@  class QEMUMachine(object):
         return events
 
     def event_wait(self, name, timeout=60.0, match=None):
-        # Test if 'match' is a recursive subset of 'event'
+        '''
+        Wait for specified timeout on named event in QMP; optionally filter
+        results by match.
+
+        The 'match' is checked to be a recursive subset of the 'event'; skips
+        branch processing on match's value None
+           {"foo": {"bar": 1}} matches {"foo": None}
+           {"foo": {"bar": 1}} does not matches {"foo": {"baz": None}}
+        '''
         def event_match(event, match=None):
             if match is None:
                 return True
@@ -226,4 +259,8 @@  class QEMUMachine(object):
         return None
 
     def get_log(self):
+        '''
+        After self.shutdown or failed qemu execution, this returns the output
+        of the qemu process.
+        '''
         return self._iolog