5 # Permission is hereby granted, free of charge, to any person obtaining a copy
6 # of this software and associated documentation files (the "Software"), to deal
7 # in the Software without restriction, including without limitation the rights
8 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9 # copies of the Software, and to permit persons to whom the Software is
10 # furnished to do so, subject to the following conditions:
12 # The above copyright notice and this permission notice shall be included in
13 # all copies or substantial portions of the Software.
15 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
28 class InvalidICS(Exception): pass
29 class IncompleteICS(InvalidICS): pass
31 def lineJoiner(oldcal, encoding='utf-8'):
32 '''Takes a string containing a calendar and returns an array of its lines'''
34 if not oldcal[0:15] == 'BEGIN:VCALENDAR':
35 raise InvalidICS, "Does not appear to be a valid ICS file"
37 if not 'END:VCALENDAR' in oldcal[-15:-1]:
38 raise IncompleteICS, "File appears to be incomplete"
40 if list(oldcal) == oldcal:
41 oldcal = '\r\n'.join(oldcal)
43 oldcal = oldcal.replace('\r\n ', '').replace('\r\n\t','')
44 return [unicode(x, encoding) for x in oldcal.strip().split('\r\n')]
47 def lineFolder(oldcal, length=75):
48 '''Folds content lines to a specified length, returns a list'''
51 sys.stderr.write('WARN: lines > 75 octets are not RFC compliant\n')
57 line = uline.encode('utf-8')
59 # Line fits inside length, do nothing
60 if len(line) <= length:
67 ufold = unicode(line[0:ll], 'utf-8', 'ignore')
68 fold = ufold.encode('utf-8')
69 uline = uline.replace(ufold,u'',1)
70 line = uline.encode('utf-8')
71 foldedline.append(fold)
73 # Subsequent lines are shorter as they include a space
75 cal.append('\r\n '.join(foldedline))
81 '''Takes a list of lines in a calendar file and returns a list of tuples
82 as (key, value) pairs'''
84 ical = [tuple(x.split(':',1)) for x in cal]
86 # Check that we got 2 items on every line
88 if not len(line) == 2:
89 raise InvalidICS, "Didn't find a content key on: %s"%(line)
95 '''Takes a list of tuples that make up a calendar file and returns it to a
98 return [':'.join(x) for x in ical]
101 def getContent(url='',stdin=False):
102 '''Generic content retriever, DO NOT use this function in a CGI script as
103 it can read from the local disk (which you probably don't want it to).
106 encoding = '' # If we don't populate this, the script will assume UTF-8
108 # Special case, if this is a HTTP url, return the data from it using
109 # the HTTP functions which attempt to play a bit nicer.
110 parsedURL = urlparse.urlparse(url)
111 if 'http' in parsedURL[0]: return getHTTPContent(url)
114 content = sys.stdin.read()
115 return (content, encoding)
118 try: content = open(os.path.abspath(url),'r').read()
119 except (IOError, OSError), e:
120 sys.stderr.write('%s\n'%e)
122 return (content, encoding)
124 # If we've survived, use python's generic URL opening library to handle it
127 res = urllib2.urlopen(url)
130 except (urllib2.URLError, OSError), e:
131 sys.stderr.write('%s\n'%e)
133 return (content, encoding)
136 def getHTTPContent(url='',cache='.httplib2-cache'):
137 '''This function attempts to play nice when retrieving content from HTTP
138 services. It's what you should use in a CGI script.'''
145 if not url: return ''
147 encoding = '' # If we don't populate this, the script will assume UTF-8
149 if 'httplib2' in sys.modules:
150 try: h = httplib2.Http('.httplib2-cache')
151 except OSError: h = httplib2.Http()
158 if 'content-type' in req[0]:
159 for ct in req[0]['content-type'].split(';'):
163 encoding = ct.split('=')[1]
164 return (content, encoding)
165 except ValueError, e:
166 sys.stderr.write('%s\n'%e)
170 content = urllib2.urlopen(url).read()
171 return (content, encoding)
172 except (urllib2.URLError, OSError), e:
173 sys.stderr.write('%s\n'%e)
180 '''Attempts to load a series of rules into a list'''
186 rules = [getattr(parserrules, rule) for rule in dir(parserrules) if callable(getattr(parserrules, rule))]
190 def applyRules(ical, rules=[], verbose=False):
191 'Runs a series of rules on the lines in ical and mangles its output'
195 if rule.__doc__ and verbose:
199 out = rule(line[0],line[1])
205 # Drop lines that are boolean False
206 if not out and not out == None: continue
208 # If the rule did something and is a tuple or a list we'll accept it
209 # otherwise, pay no attention to the man behind the curtain
211 if tuple(out) == out or list(out) == out and len(out) == 2:
212 output.append(tuple(out))
223 def writeOutput(cal, outfile=''):
224 '''Takes a list of lines and outputs to the specified file'''
227 sys.stderr.write('Refusing to write out an empty file')
234 out = open(outfile, 'w')
235 except (IOError, OSError), e:
236 sys.stderr.write('%s\n'%e)
239 if cal[-1]: cal.append('')
241 out.write('\r\n'.join(cal))
243 if not out == sys.stdout:
247 if __name__ == '__main__':
248 from optparse import OptionParser
249 # If the user passed us a 'stdin' argument, we'll go with that,
250 # otherwise we'll try for a url opener
252 parser = OptionParser('usage: %prog [options] url')
253 parser.add_option('-s', '--stdin', action='store_true', dest='stdin',
254 default=False, help='Take a calendar from standard input')
255 parser.add_option('-v', '--verbose', action='store_true', dest='verbose',
256 default=False, help='Be verbose when rules are being applied')
257 parser.add_option('-o', '--output', dest='outfile', default='',
258 help='Specify output file (defaults to standard output)')
259 parser.add_option('-m','--encoding', dest='encoding', default='',
260 help='Specify a different character encoding'
261 '(ignored if the remote server also specifies one)')
263 (options, args) = parser.parse_args()
265 if not args and not options.stdin:
268 elif not options.stdin:
273 (content, encoding) = getContent(url, options.stdin)
274 encoding = encoding or options.encoding or 'utf-8'
275 cal = lineJoiner(content, encoding)
276 ical = applyRules(splitFields(cal), generateRules(), options.verbose)
277 output = lineFolder(joinFields(ical))
278 writeOutput(output, options.outfile)