1:mod:`mimetypes` --- Map filenames to MIME types 2================================================ 3 4.. module:: mimetypes 5 :synopsis: Mapping of filename extensions to MIME types. 6 7.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org> 8 9**Source code:** :source:`Lib/mimetypes.py` 10 11.. index:: pair: MIME; content type 12 13-------------- 14 15The :mod:`mimetypes` module converts between a filename or URL and the MIME type 16associated with the filename extension. Conversions are provided from filename 17to MIME type and from MIME type to filename extension; encodings are not 18supported for the latter conversion. 19 20The module provides one class and a number of convenience functions. The 21functions are the normal interface to this module, but some applications may be 22interested in the class as well. 23 24The functions described below provide the primary interface for this module. If 25the module has not been initialized, they will call :func:`init` if they rely on 26the information :func:`init` sets up. 27 28 29.. function:: guess_type(url, strict=True) 30 31 .. index:: pair: MIME; headers 32 33 Guess the type of a file based on its filename or URL, given by *url*. The 34 return value is a tuple ``(type, encoding)`` where *type* is ``None`` if the 35 type can't be guessed (missing or unknown suffix) or a string of the form 36 ``'type/subtype'``, usable for a MIME :mailheader:`content-type` header. 37 38 *encoding* is ``None`` for no encoding or the name of the program used to encode 39 (e.g. :program:`compress` or :program:`gzip`). The encoding is suitable for use 40 as a :mailheader:`Content-Encoding` header, **not** as a 41 :mailheader:`Content-Transfer-Encoding` header. The mappings are table driven. 42 Encoding suffixes are case sensitive; type suffixes are first tried case 43 sensitively, then case insensitively. 44 45 The optional *strict* argument is a flag specifying whether the list of known MIME types 46 is limited to only the official types `registered with IANA 47 <https://www.iana.org/assignments/media-types/media-types.xhtml>`_. 48 When *strict* is ``True`` (the default), only the IANA types are supported; when 49 *strict* is ``False``, some additional non-standard but commonly used MIME types 50 are also recognized. 51 52 53.. function:: guess_all_extensions(type, strict=True) 54 55 Guess the extensions for a file based on its MIME type, given by *type*. The 56 return value is a list of strings giving all possible filename extensions, 57 including the leading dot (``'.'``). The extensions are not guaranteed to have 58 been associated with any particular data stream, but would be mapped to the MIME 59 type *type* by :func:`guess_type`. 60 61 The optional *strict* argument has the same meaning as with the :func:`guess_type` function. 62 63 64.. function:: guess_extension(type, strict=True) 65 66 Guess the extension for a file based on its MIME type, given by *type*. The 67 return value is a string giving a filename extension, including the leading dot 68 (``'.'``). The extension is not guaranteed to have been associated with any 69 particular data stream, but would be mapped to the MIME type *type* by 70 :func:`guess_type`. If no extension can be guessed for *type*, ``None`` is 71 returned. 72 73 The optional *strict* argument has the same meaning as with the :func:`guess_type` function. 74 75Some additional functions and data items are available for controlling the 76behavior of the module. 77 78 79.. function:: init(files=None) 80 81 Initialize the internal data structures. If given, *files* must be a sequence 82 of file names which should be used to augment the default type map. If omitted, 83 the file names to use are taken from :const:`knownfiles`; on Windows, the 84 current registry settings are loaded. Each file named in *files* or 85 :const:`knownfiles` takes precedence over those named before it. Calling 86 :func:`init` repeatedly is allowed. 87 88 Specifying an empty list for *files* will prevent the system defaults from 89 being applied: only the well-known values will be present from a built-in list. 90 91 If *files* is ``None`` the internal data structure is completely rebuilt to its 92 initial default value. This is a stable operation and will produce the same results 93 when called multiple times. 94 95 .. versionchanged:: 3.2 96 Previously, Windows registry settings were ignored. 97 98 99.. function:: read_mime_types(filename) 100 101 Load the type map given in the file *filename*, if it exists. The type map is 102 returned as a dictionary mapping filename extensions, including the leading dot 103 (``'.'``), to strings of the form ``'type/subtype'``. If the file *filename* 104 does not exist or cannot be read, ``None`` is returned. 105 106 107.. function:: add_type(type, ext, strict=True) 108 109 Add a mapping from the MIME type *type* to the extension *ext*. When the 110 extension is already known, the new type will replace the old one. When the type 111 is already known the extension will be added to the list of known extensions. 112 113 When *strict* is ``True`` (the default), the mapping will be added to the 114 official MIME types, otherwise to the non-standard ones. 115 116 117.. data:: inited 118 119 Flag indicating whether or not the global data structures have been initialized. 120 This is set to ``True`` by :func:`init`. 121 122 123.. data:: knownfiles 124 125 .. index:: single: file; mime.types 126 127 List of type map file names commonly installed. These files are typically named 128 :file:`mime.types` and are installed in different locations by different 129 packages. 130 131 132.. data:: suffix_map 133 134 Dictionary mapping suffixes to suffixes. This is used to allow recognition of 135 encoded files for which the encoding and the type are indicated by the same 136 extension. For example, the :file:`.tgz` extension is mapped to :file:`.tar.gz` 137 to allow the encoding and type to be recognized separately. 138 139 140.. data:: encodings_map 141 142 Dictionary mapping filename extensions to encoding types. 143 144 145.. data:: types_map 146 147 Dictionary mapping filename extensions to MIME types. 148 149 150.. data:: common_types 151 152 Dictionary mapping filename extensions to non-standard, but commonly found MIME 153 types. 154 155 156An example usage of the module:: 157 158 >>> import mimetypes 159 >>> mimetypes.init() 160 >>> mimetypes.knownfiles 161 ['/etc/mime.types', '/etc/httpd/mime.types', ... ] 162 >>> mimetypes.suffix_map['.tgz'] 163 '.tar.gz' 164 >>> mimetypes.encodings_map['.gz'] 165 'gzip' 166 >>> mimetypes.types_map['.tgz'] 167 'application/x-tar-gz' 168 169 170.. _mimetypes-objects: 171 172MimeTypes Objects 173----------------- 174 175The :class:`MimeTypes` class may be useful for applications which may want more 176than one MIME-type database; it provides an interface similar to the one of the 177:mod:`mimetypes` module. 178 179 180.. class:: MimeTypes(filenames=(), strict=True) 181 182 This class represents a MIME-types database. By default, it provides access to 183 the same database as the rest of this module. The initial database is a copy of 184 that provided by the module, and may be extended by loading additional 185 :file:`mime.types`\ -style files into the database using the :meth:`read` or 186 :meth:`readfp` methods. The mapping dictionaries may also be cleared before 187 loading additional data if the default data is not desired. 188 189 The optional *filenames* parameter can be used to cause additional files to be 190 loaded "on top" of the default database. 191 192 193 .. attribute:: MimeTypes.suffix_map 194 195 Dictionary mapping suffixes to suffixes. This is used to allow recognition of 196 encoded files for which the encoding and the type are indicated by the same 197 extension. For example, the :file:`.tgz` extension is mapped to :file:`.tar.gz` 198 to allow the encoding and type to be recognized separately. This is initially a 199 copy of the global :data:`suffix_map` defined in the module. 200 201 202 .. attribute:: MimeTypes.encodings_map 203 204 Dictionary mapping filename extensions to encoding types. This is initially a 205 copy of the global :data:`encodings_map` defined in the module. 206 207 208 .. attribute:: MimeTypes.types_map 209 210 Tuple containing two dictionaries, mapping filename extensions to MIME types: 211 the first dictionary is for the non-standards types and the second one is for 212 the standard types. They are initialized by :data:`common_types` and 213 :data:`types_map`. 214 215 216 .. attribute:: MimeTypes.types_map_inv 217 218 Tuple containing two dictionaries, mapping MIME types to a list of filename 219 extensions: the first dictionary is for the non-standards types and the 220 second one is for the standard types. They are initialized by 221 :data:`common_types` and :data:`types_map`. 222 223 224 .. method:: MimeTypes.guess_extension(type, strict=True) 225 226 Similar to the :func:`guess_extension` function, using the tables stored as part 227 of the object. 228 229 230 .. method:: MimeTypes.guess_type(url, strict=True) 231 232 Similar to the :func:`guess_type` function, using the tables stored as part of 233 the object. 234 235 236 .. method:: MimeTypes.guess_all_extensions(type, strict=True) 237 238 Similar to the :func:`guess_all_extensions` function, using the tables stored 239 as part of the object. 240 241 242 .. method:: MimeTypes.read(filename, strict=True) 243 244 Load MIME information from a file named *filename*. This uses :meth:`readfp` to 245 parse the file. 246 247 If *strict* is ``True``, information will be added to list of standard types, 248 else to the list of non-standard types. 249 250 251 .. method:: MimeTypes.readfp(fp, strict=True) 252 253 Load MIME type information from an open file *fp*. The file must have the format of 254 the standard :file:`mime.types` files. 255 256 If *strict* is ``True``, information will be added to the list of standard 257 types, else to the list of non-standard types. 258 259 260 .. method:: MimeTypes.read_windows_registry(strict=True) 261 262 Load MIME type information from the Windows registry. 263 264 .. availability:: Windows. 265 266 If *strict* is ``True``, information will be added to the list of standard 267 types, else to the list of non-standard types. 268 269 .. versionadded:: 3.2 270