Improve tracing/logging system used in lib/naclports

lib/naclports/util.py

 # Copyright 2014 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import fcntl
 import hashlib
 import os
 import shutil
 import subprocess
 import sys
@@ skipping 23 matching lines @@
 arch_to_pkgarch = {
   'x86_64': 'x86-64',
   'i686': 'i686',
   'arm': 'arm',
   'pnacl': 'pnacl',
 }
 
 # Inverse of arch_to_pkgarch
 pkgarch_to_arch = {v:k for k, v in arch_to_pkgarch.items()}
 
-verbose = False
+LOG_ERROR   = 0

[binji, 2015/03/17 19:28:12]

The logging module uses the names debug, info, warning, error, critical for
these. Maybe this should use similar names?

+LOG_WARN    = 1
+LOG_MESSAGE = 2
+LOG_VERBOSE = 3
+LOG_TRACE   = 4
+
+log_level = LOG_MESSAGE
 color_mode = 'auto'
 
 def Color(message, color):
   if termcolor and Color.enabled:
     return termcolor.colored(message, color)
   else:
     return message
 
 
 def CheckStdoutForColorSupport():
@@ skipping 11 matching lines @@
     def __call__(self, *args):
       return self[args]
 
     def __missing__(self, key):
       ret = self[key] = self.f(*key)
       return ret
 
   return Memo(f)
 
 
-def SetVerbose(verbosity):
-  global verbose
-  verbose = verbosity
+def SetVerbose(enabled):
+  if enabled:
+    SetLogLevel(LOG_VERBOSE)
+  else:
+    SetLogLevel(LOG_MESSAGE)
 
 
-def Log(message):
+def SetLogLevel(verbosity):
+  global log_level
+  log_level = verbosity
+
+
+def Log(message, verbosity=LOG_MESSAGE):
   """Log a message to the console (stdout)."""
+  if log_level < verbosity:
+    return
   sys.stdout.write(str(message) + '\n')
   sys.stdout.flush()
 
 
 def LogHeading(message, suffix=''):
   """Log a colored/highlighted message with optional suffix."""
   if Color.enabled:
     Log(Color(message, 'green') + suffix)
   else:
-    if verbose:
+    if log_level > LOG_WARN:
       # When running in verbose mode make sure heading standout
       Log('###################################################################')
       Log(message + suffix)
       Log('###################################################################')
     else:
       Log(message + suffix)
 
 
 def Warn(message):
-  Log('warning: ' + message)
+  Log('warning: ' + message, LOG_WARN)
 
 
 def Trace(message):
-  """Log a message to the console if running in verbose mode (-v)."""
-  if verbose:
-    Log(message)
+  Log(message, LOG_TRACE)
+
+
+def LogVerbose(message):
+  Log(message, LOG_VERBOSE)
 
 
 def FindInPath(command_name):
   """Search user's PATH for a given executable.
 
   Returns:
     Full path to executable.
   """
   if os.name == 'nt':
     extensions = ('.bat', '.com', '.exe')
@@ skipping 24 matching lines @@
   if hasattr(sys.stdout, 'fileno') and os.isatty(sys.stdout.fileno()):
     # Add --progress-bar but only if stdout is a TTY device.
     curl_cmd.append('--progress-bar')
   else:
     # otherwise suppress status output, since curl always assumes its
     # talking to a TTY and writes \r and \b characters.  But add
     # --show-error so that when curl fails it at least prints something.
     curl_cmd += ['--silent', '--show-error']
   curl_cmd.append(url)
 
-  if verbose:
+  if log_level > LOG_WARN:
     Log('Downloading: %s [%s]' % (url, filename))
   else:
     Log('Downloading: %s' % url.replace(GS_URL, ''))
   try:
     subprocess.check_call(curl_cmd)
   except subprocess.CalledProcessError as e:
     raise error.Error('Error downloading file: %s' % str(e))
 
   os.rename(temp_filename, filename)
 
@@ skipping 245 matching lines @@
 
 
 class InstallLock(Lock):
   """Lock used when installing/uninstalling package"""
   def __init__(self, config):
     root = GetInstallRoot(config)
     super(InstallLock, self).__init__(root)
 
 
 CheckStdoutForColorSupport()