cpython/Lib/mimetypes.py
Fred Drake eeee4ec4f1 Refactor so that it is easier to work with alternate MIME types databases,
and programmatically extend the database in different ways.

This closes the SF bug (feature request) #439710.
2001-08-03 21:01:44 +00:00

314 lines
9.8 KiB
Python

"""Guess the MIME type of a file.
This module defines two useful functions:
guess_type(url) -- guess the MIME type and encoding of a URL.
guess_extension(type) -- guess the extension for a given MIME type.
It also contains the following, for tuning the behavior:
Data:
knownfiles -- list of files to parse
inited -- flag set when init() has been called
suffix_map -- dictionary mapping suffixes to suffixes
encodings_map -- dictionary mapping suffixes to encodings
types_map -- dictionary mapping suffixes to types
Functions:
init([files]) -- parse a list of files, default knownfiles
read_mime_types(file) -- parse one file, return a dictionary or None
"""
import os
import posixpath
import urllib
__all__ = ["guess_type","guess_extension","read_mime_types","init"]
knownfiles = [
"/usr/local/etc/httpd/conf/mime.types",
"/usr/local/lib/netscape/mime.types",
"/usr/local/etc/httpd/conf/mime.types", # Apache 1.2
"/usr/local/etc/mime.types", # Apache 1.3
]
inited = 0
class MimeTypes:
"""MIME-types datastore.
This datastore can handle information from mime.types-style files
and supports basic determination of MIME type from a filename or
URL, and can guess a reasonable extension given a MIME type.
"""
def __init__(self, filenames=()):
if not inited:
init()
self.encodings_map = encodings_map.copy()
self.suffix_map = suffix_map.copy()
self.types_map = types_map.copy()
for name in filenames:
self.read(name)
def guess_type(self, url):
"""Guess the type of a file based on its URL.
Return value is a tuple (type, encoding) where type is None if
the type can't be guessed (no or unknown suffix) or a string
of the form type/subtype, usable for a MIME Content-type
header; and encoding is None for no encoding or the name of
the program used to encode (e.g. compress or gzip). The
mappings are table driven. Encoding suffixes are case
sensitive; type suffixes are first tried case sensitive, then
case insensitive.
The suffixes .tgz, .taz and .tz (case sensitive!) are all
mapped to '.tar.gz'. (This is table-driven too, using the
dictionary suffix_map.)
"""
scheme, url = urllib.splittype(url)
if scheme == 'data':
# syntax of data URLs:
# dataurl := "data:" [ mediatype ] [ ";base64" ] "," data
# mediatype := [ type "/" subtype ] *( ";" parameter )
# data := *urlchar
# parameter := attribute "=" value
# type/subtype defaults to "text/plain"
comma = url.find(',')
if comma < 0:
# bad data URL
return None, None
semi = url.find(';', 0, comma)
if semi >= 0:
type = url[:semi]
else:
type = url[:comma]
if '=' in type or '/' not in type:
type = 'text/plain'
return type, None # never compressed, so encoding is None
base, ext = posixpath.splitext(url)
while self.suffix_map.has_key(ext):
base, ext = posixpath.splitext(base + self.suffix_map[ext])
if self.encodings_map.has_key(ext):
encoding = self.encodings_map[ext]
base, ext = posixpath.splitext(base)
else:
encoding = None
types_map = self.types_map
if types_map.has_key(ext):
return types_map[ext], encoding
elif types_map.has_key(ext.lower()):
return types_map[ext.lower()], encoding
else:
return None, encoding
def guess_extension(self, type):
"""Guess the extension for a file based on its MIME type.
Return value is a string giving a filename extension,
including the leading dot ('.'). The extension is not
guaranteed to have been associated with any particular data
stream, but would be mapped to the MIME type `type' by
guess_type(). If no extension can be guessed for `type', None
is returned.
"""
type = type.lower()
for ext, stype in self.types_map.items():
if type == stype:
return ext
return None
def read(self, filename):
"""Read a single mime.types-format file, specified by pathname."""
fp = open(filename)
self.readfp(fp)
fp.close()
def readfp(self):
"""Read a single mime.types-format file."""
map = self.types_map
while 1:
line = f.readline()
if not line:
break
words = line.split()
for i in range(len(words)):
if words[i][0] == '#':
del words[i:]
break
if not words:
continue
type, suffixes = words[0], words[1:]
for suff in suffixes:
map['.' + suff] = type
def guess_type(url):
"""Guess the type of a file based on its URL.
Return value is a tuple (type, encoding) where type is None if the
type can't be guessed (no or unknown suffix) or a string of the
form type/subtype, usable for a MIME Content-type header; and
encoding is None for no encoding or the name of the program used
to encode (e.g. compress or gzip). The mappings are table
driven. Encoding suffixes are case sensitive; type suffixes are
first tried case sensitive, then case insensitive.
The suffixes .tgz, .taz and .tz (case sensitive!) are all mapped
to ".tar.gz". (This is table-driven too, using the dictionary
suffix_map).
"""
init()
return guess_type(url)
def guess_extension(type):
"""Guess the extension for a file based on its MIME type.
Return value is a string giving a filename extension, including the
leading dot ('.'). The extension is not guaranteed to have been
associated with any particular data stream, but would be mapped to the
MIME type `type' by guess_type(). If no extension can be guessed for
`type', None is returned.
"""
init()
return guess_extension(type)
def init(files=None):
global guess_extension, guess_type
global suffix_map, types_map, encodings_map
global inited
inited = 1
db = MimeTypes()
if files is None:
files = knownfiles
for file in files:
if os.path.isfile(file):
db.readfp(open(file))
encodings_map = db.encodings_map
suffix_map = db.encodings_map
types_map = db.types_map
guess_extension = db.guess_extension
guess_type = db.guess_type
def read_mime_types(file):
try:
f = open(file)
except IOError:
return None
db = MimeTypes()
db.readfp(f)
return db.types_map
suffix_map = {
'.tgz': '.tar.gz',
'.taz': '.tar.gz',
'.tz': '.tar.gz',
}
encodings_map = {
'.gz': 'gzip',
'.Z': 'compress',
}
types_map = {
'.a': 'application/octet-stream',
'.ai': 'application/postscript',
'.aif': 'audio/x-aiff',
'.aifc': 'audio/x-aiff',
'.aiff': 'audio/x-aiff',
'.au': 'audio/basic',
'.avi': 'video/x-msvideo',
'.bcpio': 'application/x-bcpio',
'.bin': 'application/octet-stream',
'.cdf': 'application/x-netcdf',
'.cpio': 'application/x-cpio',
'.csh': 'application/x-csh',
'.dll': 'application/octet-stream',
'.dvi': 'application/x-dvi',
'.exe': 'application/octet-stream',
'.eps': 'application/postscript',
'.etx': 'text/x-setext',
'.gif': 'image/gif',
'.gtar': 'application/x-gtar',
'.hdf': 'application/x-hdf',
'.htm': 'text/html',
'.html': 'text/html',
'.ief': 'image/ief',
'.jpe': 'image/jpeg',
'.jpeg': 'image/jpeg',
'.jpg': 'image/jpeg',
'.js': 'application/x-javascript',
'.latex': 'application/x-latex',
'.man': 'application/x-troff-man',
'.me': 'application/x-troff-me',
'.mif': 'application/x-mif',
'.mov': 'video/quicktime',
'.movie': 'video/x-sgi-movie',
'.mpe': 'video/mpeg',
'.mpeg': 'video/mpeg',
'.mpg': 'video/mpeg',
'.ms': 'application/x-troff-ms',
'.nc': 'application/x-netcdf',
'.o': 'application/octet-stream',
'.obj': 'application/octet-stream',
'.oda': 'application/oda',
'.pbm': 'image/x-portable-bitmap',
'.pdf': 'application/pdf',
'.pgm': 'image/x-portable-graymap',
'.pnm': 'image/x-portable-anymap',
'.png': 'image/png',
'.ppm': 'image/x-portable-pixmap',
'.ps': 'application/postscript',
'.py': 'text/x-python',
'.pyc': 'application/x-python-code',
'.pyo': 'application/x-python-code',
'.qt': 'video/quicktime',
'.ras': 'image/x-cmu-raster',
'.rgb': 'image/x-rgb',
'.rdf': 'application/xml',
'.roff': 'application/x-troff',
'.rtf': 'application/rtf',
'.rtx': 'text/richtext',
'.sgm': 'text/x-sgml',
'.sgml': 'text/x-sgml',
'.sh': 'application/x-sh',
'.shar': 'application/x-shar',
'.snd': 'audio/basic',
'.so': 'application/octet-stream',
'.src': 'application/x-wais-source',
'.sv4cpio': 'application/x-sv4cpio',
'.sv4crc': 'application/x-sv4crc',
'.t': 'application/x-troff',
'.tar': 'application/x-tar',
'.tcl': 'application/x-tcl',
'.tex': 'application/x-tex',
'.texi': 'application/x-texinfo',
'.texinfo': 'application/x-texinfo',
'.tif': 'image/tiff',
'.tiff': 'image/tiff',
'.tr': 'application/x-troff',
'.tsv': 'text/tab-separated-values',
'.txt': 'text/plain',
'.ustar': 'application/x-ustar',
'.wav': 'audio/x-wav',
'.xbm': 'image/x-xbitmap',
'.xml': 'text/xml',
'.xsl': 'application/xml',
'.xpm': 'image/x-xpixmap',
'.xwd': 'image/x-xwindowdump',
'.zip': 'application/zip',
}
if __name__ == '__main__':
import sys
print guess_type(sys.argv[1])