MIME::Types
Section: User Contributed Perl Documentation (3)
Updated: 2021-01-27
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NAME
MIME::Types - Definition of MIME types
INHERITANCE
MIME::Types
is a Exporter
SYNOPSIS
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')
DESCRIPTION
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.
METHODS
Constructors
- MIME::Types->new(%options)
-
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.
-
Knowledge
- $obj->addType($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...
- $obj->extensions()
-
Returns a list of all defined extensions.
- $obj->listTypes()
-
Returns a list of all defined mime-types by name only. This will not
instantiate MIME::Type objects. See types()
- $obj->mimeTypeOf($filename)
-
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;
- $obj->type($string)
-
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.
- $obj->types()
-
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
- $obj->httpAccept($header)
-
[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
example:
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.
example:
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 $accept is "undef", the first
filename is returned.
example:
use HTTP::Status ':constants';
use File::Glob 'bsd_glob'; # understands blanks in filename
my @filenames = bsd_glob "$imagedir/$fnbase.*;
my $accept = $req->header('Accept');
my ($fn, $mime) = $mt->httpAcceptSelect($accept, @filenames);
my $code = defined $mime ? HTTP_NOT_ACCEPTABLE : HTTP_OK;
FUNCTIONS
The next functions are provided for backward compatibility with MIME::Types
versions [0.06] and below. This code originates from Jeff Okamoto
okamoto@corp.hp.com and others.
- by_mediatype(TYPE)
-
This function takes a media type and returns a list or anonymous array of
anonymous three-element arrays whose values are the file name suffix used to
identify it, the media type, and a content encoding.
TYPE can be a full type name (contains '/', and will be matched in full),
a partial type (which is used as regular expression) or a real regular
expression.
- by_suffix(FILENAME|SUFFIX)
-
Like "mimeTypeOf", but does not return an "MIME::Type" object. If the file
+type is unknown, both the returned media type and encoding are empty strings.
example: use of function by_suffix()
use MIME::Types 'by_suffix';
my ($mediatype, $encoding) = by_suffix('image.gif');
my $refdata = by_suffix('image.gif');
my ($mediatype, $encoding) = @$refdata;
- import_mime_types()
-
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.
SEE ALSO
This module is part of MIME-Types distribution version 2.18,
built on December 09, 2020. Website:
http://perl.overmeer.net/CPAN/
LICENSE
Copyrights 1999-2020 by [Mark Overmeer <
markov@cpan.org>]. 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://dev.perl.org/licenses/