blob: a897a16d11178c000eadc3ff81a81731217865f2 [file] [log] [blame]
#!/usr/bin/env python3
# Copyright (c) 2011, the Dart project authors. Please see the AUTHORS file
# for details. All rights reserved. Use of this source code is governed by a
# BSD-style license that can be found in the LICENSE file.
"""Templating to help generate structured text."""
import os
import sys
import subprocess
import time
import emitter
import logging
_logger = logging.getLogger('multiemitter')
class MultiEmitter(object):
"""A set of Emitters that write to different files.
Each entry has a key.
file --> emitter
key --> emitter
def __init__(self, logging_level=logging.WARNING):
self._key_to_emitter = {} # key -> Emitter
self._filename_to_emitter = {} # filename -> Emitter
def FileEmitter(self, filename, key=None):
"""Creates an emitter for writing to a file.
When this MultiEmitter is flushed, the contents of the emitter are written
to the file.
filename: a string, the path name of the file
key: provides an access key to retrieve the emitter.
Returns: the emitter.
e = emitter.Emitter()
self._filename_to_emitter[filename] = e
if key:
self.Associate(key, e)
return e
def Associate(self, key, emitter):
"""Associates a key with an emitter."""
self._key_to_emitter[key] = emitter
def Find(self, key):
"""Returns the emitter associated with |key|."""
return self._key_to_emitter[key]
def Flush(self, writer=None):
"""Writes all pending files.
writer: a function called for each file and it's lines.
if not writer:
writer = _WriteFile
for file in sorted(self._filename_to_emitter.keys()):
emitter = self._filename_to_emitter[file]
writer(file, emitter.Fragments())
def _WriteFile(path, lines):
(dir, file) = os.path.split(path)
# Ensure dir exists.
if dir:
if not os.path.isdir(dir):'Mkdir - %s' % dir)
# If file exists and is unchanged, return.
new_contents = ''.join(lines)
if os.path.exists(path):
with open(path) as fd:
contents =
if new_contents == contents:'Unchanged file %s' % path)
# Write the file.
num_attempts = 4
for i in range(num_attempts):
try:'Writing (attempt %d) - %s' % (i + 1, path))
with open(path, 'w') as fd:
except IOError as error:
last_attempt = (i == (num_attempts - 1))
if not last_attempt:
# Sleep for 50 ms and try again
else:'Got exception (%s) ' % error)
raise error