mirror/mirror-index/make-index.py

167 lines
5.9 KiB
Python
Executable File

#!/usr/bin/env python
"""make-index.py
Generates an nice index of the directories from a
template.
Original Author: Jeremy Roman <jbroman@csclub.uwaterloo.ca>
So if you don't like how I did something,
I'm the person you get to complain to.
Please be gentle.
"""
import os, sys, time
from subprocess import Popen, PIPE
from optparse import OptionParser
import yaml, mako.exceptions, webhelpers.html.tags
from mako.template import Template
def reformat_size(size):
"""Reformats '124M' to '124 MB', et cetera."""
if size[-1].isalpha():
return size[:-1] + " " + size[-1] + "B"
else:
return size
def atomic_write(filename, body):
"""Atomically write to a file by writing a
temporary file and then moving it to replace
the desired output file.
This ensures that partial files are never seen
by clients."""
# generate an appropriate temporary filename
# in the same directory
tmp_filename = "%s.%d.tmp" % (filename, os.getpid())
# open the directory so that we can fsync it
dir = os.open(os.path.realpath(os.path.dirname(filename)), \
os.O_DIRECTORY | os.O_RDONLY)
# write to the temporary file
tmp = open(tmp_filename, 'w')
print >>tmp, body
tmp.flush()
os.fsync(tmp.fileno())
tmp.close()
# atomically replace the actual file
os.rename(tmp_filename, filename)
os.fsync(dir)
os.close(dir)
def main():
# accept command-line arguments
parser = OptionParser()
parser.add_option("-c", "--config", dest="config", default="config.yaml",
help="configuration file to be used", metavar="FILE")
parser.add_option("-D", "--docroot", dest="docroot",
help="directory to be scanned", metavar="DIR")
parser.add_option("-F", "--duflags", dest="duflags",
help="flags to be passed to du, replaces any in config")
parser.add_option("-o", "--output", dest="output", metavar="FILE",
help="file to which index page will be written. "
"Use /dev/stdout to send to standard out.")
parser.add_option("-t", "--template", dest="template",
help="Mako template to render", metavar="FILE")
parser.add_option("--nonatomic", dest="nonatomic", action="store_true",
default=False, help="write the output to the path "
"given without creating a temporary file in between. "
"This is automatically set if the output appears "
"to be a character device, not a file.")
(options, args) = parser.parse_args()
# load config file
try:
config = yaml.load(file(options.config,'r'))
except:
config = None
if not config or type(config) != dict:
print >>sys.stderr, "Unable to load configuration '%s'." % options.config
sys.exit(-1)
# determine important variables based on an appropriate order of
# precedence (command-line flags first, then the config file,
# then built-in fallbacks)
#
# fallback value for nonatomic is used so that character devices
# (e.g. /dev/stdout, /dev/null) are written to in the regular way
docroot = options.docroot or config.get('docroot')
duflags = options.duflags or config.get('duflags') or "-h --max-depth=1"
output = options.output or config.get('output')
template = options.template or config.get("template") or "index.mako"
nonatomic = options.nonatomic or config.get("nonatomic") or \
(os.path.exists(output) and not os.path.isfile(output))
# sanity checks
if not docroot:
print >>sys.stderr, "docroot not specified."
print >>sys.stderr, "Define it in the config file or pass -D on the command line."
sys.exit(-1)
elif not output:
print >>sys.stderr, "output not specified."
print >>sys.stderr, "Define it in the config file or pass -o on the command line."
elif not config.get('directories'):
print >>sys.stderr, "directories not specified."
print >>sys.stderr, "Define it in the config file."
sys.exit(-1)
elif not os.path.isdir(docroot):
print >>sys.stderr, "docroot '%s' not found or not a directory." % docroot
sys.exit(-1)
elif not os.path.exists(template) or os.path.isdir(template):
print >>sys.stderr, "template '%s' not found or is a directory." % template
sys.exit(-1)
# Call du to compute size
du = Popen(
"/usr/bin/du %s %s | /usr/bin/sort -fk2" % (docroot, duflags),
shell=True, stdout=PIPE, stderr=PIPE).communicate()
# Check that du executed successfully
# If there's anything on stderr, send it
# out our own stderr and terminate.
if len(du[1].strip()) > 0:
sys.stderr.write(du[1])
print >>sys.stderr, "du terminated unsuccessfully. Not generating index."
sys.exit(-1)
# first one should be total, grab its size and format
du = du[0].splitlines() # we only care about stdout now
total_size = reformat_size(du[0].split(None,2)[0])
# the rest are the sizes we want
directories = []
for line in du[1:]:
(size, dir) = line.split(None, 2)
dir = os.path.basename(dir)
info = {'dir':dir, 'size':reformat_size(size)}
# use info from config.yaml, if found
# otherwise, skip this directory
if dir in config['directories']:
info.update(config['directories'][dir])
else:
continue
directories.append(info)
# render the template to a string
body = Template(filename=template).render(
total_size=total_size,
directories=directories,
config=config,
h=webhelpers.html.tags)
# write the rendered output
if nonatomic:
print >>file(output,'w'), body
else:
atomic_write(output, body)
if __name__ == "__main__":
main()