import sys
import urlparse
import os
+from cgi import parse_header
+
class InvalidICS(Exception): pass
-class notJoined(Exception): pass
+class IncompleteICS(InvalidICS): pass
-def lineJoiner(oldcal):
+def lineJoiner(oldcal, encoding='utf-8'):
'''Takes a string containing a calendar and returns an array of its lines'''
+ try:
+ oldcal = unicode(oldcal, encoding)
+ oldcal = oldcal.replace('\r\n ', '').replace('\r\n\t','')
+ except UnicodeDecodeError:
+ # This is probably a file with badly folded lines
+ oldcal = oldcal.replace('\r\n ', '').replace('\r\n\t','')
+ try: oldcal = unicode(oldcal, encoding)
+ except UnicodeDecodeError:
+ sys.stderr.write('Malformed File')
+ raise
+
+ if not oldcal[0:15] == 'BEGIN:VCALENDAR':
+ raise InvalidICS, "Does not appear to be a valid ICS file"
+
+ if not 'END:VCALENDAR' in oldcal[-15:-1]:
+ raise IncompleteICS, "File appears to be incomplete"
if list(oldcal) == oldcal:
oldcal = '\r\n'.join(oldcal)
- oldcal.replace('\r\n ', '')
return oldcal.split('\r\n')
cal = []
sl = length - 1
- for line in oldcal:
+ for uline in oldcal:
+ line = uline.encode('utf-8')
+
# Line fits inside length, do nothing
- if len(line.rstrip()) <= length:
+ if len(line) <= length:
cal.append(line)
+
else:
- brokenline = [line[0:length] + '\r\n']
ll = length
- while ll < len(line.rstrip('\r\n')) + 1:
- brokenline.append(' ' + line[ll:sl+ll].rstrip('\r\n') + '\r\n')
- ll += sl
- cal += brokenline
+ foldedline = []
+ while uline:
+ ufold = unicode(line[0:ll], 'utf-8', 'ignore')
+ fold = ufold.encode('utf-8')
+ uline = uline.replace(ufold,u'',1)
+ line = uline.encode('utf-8')
+ foldedline.append(fold)
+
+ # Subsequent lines are shorter as they include a space
+ ll = length - 1
+ cal.append('\r\n '.join(foldedline))
return cal
+
+def splitFields(cal):
+ '''Takes a list of lines in a calendar file and returns a list of tuples
+ as (key, value) pairs'''
+
+ ical = []
+
+ # Check that we got 2 items on every line
+ for line in [tuple(x.split(':',1)) for x in cal]:
+ if not len(line) == 2 and line[0]:
+ raise InvalidICS, 'Unusual content line: %s'%line
+ elif line[0]:
+ ical.append(line)
+
+ return ical
+
+
+def joinFields(ical):
+ '''Takes a list of tuples that make up a calendar file and returns it to a
+ list of lines'''
+
+ return [':'.join(x) for x in ical]
+
+
def getContent(url='',stdin=False):
'''Generic content retriever, DO NOT use this function in a CGI script as
it can read from the local disk (which you probably don't want it to).
'''
+ encoding = '' # If we don't populate this, the script will assume UTF-8
+
# Special case, if this is a HTTP url, return the data from it using
# the HTTP functions which attempt to play a bit nicer.
parsedURL = urlparse.urlparse(url)
if stdin:
content = sys.stdin.read()
- return content
+ return (content, encoding)
- if not parsedURL[0]:
- try: content = open(os.path.abspath(url),'r').read()
- except (IOError, OSError), e:
- sys.stderr.write('%s\n'%e)
- sys.exit(1)
- return content
+ if not parsedURL[0]: url = 'file://' + os.path.abspath(url)
# If we've survived, use python's generic URL opening library to handle it
import urllib2
try:
res = urllib2.urlopen(url)
content = res.read()
+ ct = res.info().getplist()
res.close()
- except (urllib2.URLError, ValueError), e:
+ except (urllib2.URLError, OSError), e:
sys.stderr.write('%s\n'%e)
sys.exit(1)
- return content
+
+ for param in ct:
+ if 'charset' in param:
+ encoding = param.split('=')[1]
+ break
+
+ return (content, encoding)
def getHTTPContent(url='',cache='.httplib2-cache'):
'''This function attempts to play nice when retrieving content from HTTP
- services. It's what you should use in a CGI script. It will (by default)
- slurp the first 20 bytes of the file and check that we are indeed looking
- at an ICS file before going for broke.'''
+ services. It's what you should use in a CGI script.'''
try:
import httplib2
except ImportError:
import urllib2
- if not url: return ''
+ if not url: return ('','')
+
+ if not 'http' in urlparse.urlparse(url)[0]: return ('','')
if 'httplib2' in sys.modules:
try: h = httplib2.Http('.httplib2-cache')
except OSError: h = httplib2.Http()
else: h = False
+ if h:
+ try:
+ req = h.request(url)
+ except ValueError, e:
+ sys.stderr.write('%s\n'%e)
+ sys.exit(1)
+
+ resp, content = req
+ if 'content-type' in resp:
+ ct = 'Content-Type: %s'%req[0]['content-type']
+ ct = parse_header(ct)
+ if 'charset' in ct[1]: encoding = ct[1]['charset']
+ else: encoding = ''
+ else:
+ ct = ''
+ encoding = ''
+
+ else:
+ try:
+ req = urllib2.urlopen(url)
+ except urllib2.URLError, e:
+ sys.stderr.write('%s\n'%e)
+ sys.exit(1)
+
+ content = req.read()
+ ct = req.info().getplist()
+ for param in ct:
+ if 'charset' in param:
+ encoding = param.split('=')[1]
+ break
+
+ return (content, encoding)
+
+
+def generateRules():
+ '''Attempts to load a series of rules into a list'''
try:
- if h: content = h.request(url)[1]
- return content
- except ValueError, e:
- sys.stderr.write('%s\n'%e)
- sys.exit(1)
+ import parserrules
+ except ImportError:
+ return []
+
+ rules = [getattr(parserrules, rule) for rule in dir(parserrules) if callable(getattr(parserrules, rule))]
+ return rules
+
+
+def applyRules(ical, rules=[], verbose=False):
+ 'Runs a series of rules on the lines in ical and mangles its output'
+
+ for rule in rules:
+ output = []
+ if rule.__doc__ and verbose:
+ print(rule.__doc__)
+ for line in ical:
+ try:
+ out = rule(line[0],line[1])
+ except TypeError, e:
+ output.append(line)
+ print(e)
+ continue
+
+ # Drop lines that are boolean False
+ if not out and not out == None: continue
+
+ # If the rule did something and is a tuple or a list we'll accept it
+ # otherwise, pay no attention to the man behind the curtain
+ try:
+ if tuple(out) == out or list(out) == out and len(out) == 2:
+ output.append(tuple(out))
+ else:
+ output.append(line)
+ except TypeError, e:
+ output.append(line)
+
+ ical = output
+
+ return ical
+
+
+def writeOutput(cal, outfile=''):
+ '''Takes a list of lines and outputs to the specified file'''
+
+ if not cal:
+ sys.stderr.write('Refusing to write out an empty file')
+ sys.exit(0)
+
+ if not outfile:
+ out = sys.stdout
+ else:
+ try:
+ out = open(outfile, 'w')
+ except (IOError, OSError), e:
+ sys.stderr.write('%s\n'%e)
+ sys.exit(1)
+
+ if cal[-1]: cal.append('')
+
+ out.write('\r\n'.join(cal))
+
+ if not out == sys.stdout:
+ out.close()
+
+
+def vobjectRules(ics):
+ '''Applies rules to the ICS file before we have our way with it'''
try:
- content = urllib2.urlopen(url).read()
- return content
- except urllib2.URLError, e:
- sys.stderr.write('%s\n'%e)
- sys.exit(1)
+ import vobjectRules
+ except ImportError:
+ sys.stderr.write('Vobject rules file could not be imported\n')
+ return ics
+
+ for rule in vobjectRules.runRules:
+ ics = rule(ics)
+
+ return ics
- return ''
if __name__ == '__main__':
from optparse import OptionParser
parser = OptionParser('usage: %prog [options] url')
parser.add_option('-s', '--stdin', action='store_true', dest='stdin',
default=False, help='Take a calendar from standard input')
+ parser.add_option('-v', '--verbose', action='store_true', dest='verbose',
+ default=False, help='Be verbose when rules are being applied')
parser.add_option('-o', '--output', dest='outfile', default='',
help='Specify output file (defaults to standard output)')
+ parser.add_option('-m','--encoding', dest='encoding', default='',
+ help='Specify a different character encoding'
+ '(ignored if the remote server also specifies one)')
+ parser.add_option('-r','--vobject-rules',
+ action='store_true', dest='vobject',
+ help='Run rules written for vobject stored in vobjectRules.py')
(options, args) = parser.parse_args()
else:
url = ''
- content = getContent(url, options.stdin)
+ (content, encoding) = getContent(url, options.stdin)
+ encoding = encoding or options.encoding or 'utf-8'
+ if options.vobject: content = vobjectRules(content)
+ cal = lineJoiner(content, encoding)
+ ical = applyRules(splitFields(cal), generateRules(), options.verbose)
+ output = lineFolder(joinFields(ical))
+ writeOutput(output, options.outfile)