MIME::Types(3) Definition of MIME types


   is a Exporter


use MIME::Types;
my $mt = MIME::Types->new(...); # MIME::Types object
my $type = $mt->type('text/plain'); # MIME::Type object
my $type = $mt->mimeTypeOf('gif');
my $type = $mt->mimeTypeOf('picture.jpg');
my @types = $mt->httpAccept('text/html, application/json;q=0.1')


MIME types are used in many applications (for instance as part of e-mail and HTTP traffic) to indicate the type of content which is transmitted. or expected. See RFC2045 at https://www.ietf.org/rfc/rfc2045.txt

Sometimes detailed knowledge about a mime-type is need, however this module only knows about the file-name extensions which relate to some filetype. It can also be used to produce the right format: types which are not registered at IANA need to use 'x-' prefixes.

This object administers a huge list of known mime-types, combined from various sources. For instance, it contains all IANA types and the knowledge of Apache. Probably the most complete table on the net!

MIME::Types and daemons (fork)

If your program uses fork (usually for a daemon), then you want to have the type table initialized before you start forking. So, first call

   my $mt = MIME::Types->new;

Later, each time you create this object (you may, of course, also reuse the object you create here) you will get access to the same global table of types.



Create a new "MIME::Types" object which manages the data. In the current implementation, it does not matter whether you create this object often within your program, but in the future this may change.

 -Option         --Default
  db_file          <installed source>
  only_complete    <false>
  only_iana        <false>
  skip_extensions  <false>
db_file => FILENAME
The location of the database which contains the type information. Only the first instantiation of this object will have this parameter obeyed.

[2.10] This parameter can be globally overruled via the "PERL_MIME_TYPE_DB" environment variable, which may be needed in case of PAR or other tricky installations. For PAR, you probably set this environment variable to ``inc/lib/MIME/types.db''

only_complete => BOOLEAN
Only include complete MIME type definitions: requires at least one known extension. This will reduce the number of entries --and with that the amount of memory consumed--- considerably.

In your program you have to decide: the first time that you call the creator ("new") determines whether you get the full or the partial information.

only_iana => BOOLEAN
Only load the types which are currently known by IANA.
skip_extensions => BOOLEAN
Do not load the table to map extensions to types, which is quite large.


$obj->addType($type, ...)
Add one or more TYPEs to the set of known types. Each TYPE is a "MIME::Type" which must be experimental: either the main-type or the sub-type must start with "x-".

Please inform the maintainer of this module when registered types are missing. Before version MIME::Types version 1.14, a warning was produced when an unknown IANA type was added. This has been removed, because some people need that to get their application to work locally... broken applications...

Returns a list of all defined extensions.
Returns a list of all defined mime-types by name only. This will not instantiate MIME::Type objects. See types()
Returns the "MIME::Type" object which belongs to the FILENAME (or simply its filename extension) or "undef" if the file type is unknown. The extension is used and considered case-insensitive.

In some cases, more than one type is known for a certain filename extension. In that case, the preferred one is taken (for an unclear definition of preference)

example: use of mimeTypeOf()

 my $types = MIME::Types->new;
 my $mime = $types->mimeTypeOf('gif');
 my $mime = $types->mimeTypeOf('picture.jpg');
 print $mime->isBinary;
Returns the "MIME::Type" which describes the type related to STRING. [2.00] Only one type will be returned.

[before 2.00] One type may be described more than once. Different extensions may be in use for this type, and different operating systems may cause more than one "MIME::Type" object to be defined. In scalar context, only the first is returned.

Returns a list of all defined mime-types. For reasons of backwards compatibility, this will instantiate MIME::Type objects, which will be returned. See listTypes().

HTTP support

[2.07] Decompose a typical HTTP-Accept header, and sort it based on the included priority information. Returned is a sorted list of type names, where the highest priority type is first. The list may contain '*/*' (accept any) or a '*' as subtype.

Ill-formated typenames are ignored. On equal qualities, the order is kept. See RFC2616 section 14.1


  my @types = $types->httpAccept('text/html, application/json;q=0.9');
$obj->httpAcceptBest($accept|\@types, @have)
[2.07] The $accept string is processed via httpAccept() to order the types on preference. You may also provide a list of ordered @types which may have been the result of that method, called earlier.

As second parameter, you pass a LIST of types you @have to offer. Those need to be MIME::Type objects. The preferred type will get selected. When none of these are accepted by the client, this will return "undef". It should result in a 406 server response.


   my $accept = $req->header('Accept');
   my @have   = map $mt->type($_), qw[text/plain text/html];
   my @ext    = $mt->httpAcceptBest($accept, @have);
$obj->httpAcceptSelect($accept|\@types, @filenames|\@filenames)
[2.07] Like httpAcceptBest(), but now we do not return a pair with mime-type and filename, not just the type. If $accept is "undef", the first filename is returned.


   use HTTP::Status ':constants';
   use File::Glob   'bsd_glob';    # understands blanks in filename
   my @filenames   = bsd_glob "$imagedir/$fnbase.*;
   my $accept      = $req->header('Accept');
   my ($fn, $mime) = $mt->httpAcceptSelect($accept, @filenames);
   my $code        = defined $mime ? HTTP_NOT_ACCEPTABLE : HTTP_OK;


The next functions are provided for backward compatibility with MIME::Types versions [0.06] and below. This code originates from Jeff Okamoto [email protected] and others.
This function takes a media type and returns a list or anonymous array of anonymous three-element arrays whose values are the file name suffix used to identify it, the media type, and a content encoding.

TYPE can be a full type name (contains '/', and will be matched in full), a partial type (which is used as regular expression) or a real regular expression.

Like "mimeTypeOf", but does not return an "MIME::Type" object. If the file +type is unknown, both the returned media type and encoding are empty strings.

example: use of function by_suffix()

 use MIME::Types 'by_suffix';
 my ($mediatype, $encoding) = by_suffix('image.gif');
 my $refdata = by_suffix('image.gif');
 my ($mediatype, $encoding) = @$refdata;
This method has been removed: mime-types are only useful if understood by many parties. Therefore, the IANA assigns names which can be used. In the table kept by this "MIME::Types" module all these names, plus the most often used temporary names are kept. When names seem to be missing, please contact the maintainer for inclusion.


Copyrights 1999,2001-2016 by [Mark Overmeer]. For other contributors see ChangeLog.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See http://www.perl.com/perl/misc/Artistic.html