class MIME::Types
MIME::Types is a registry of MIME types. It is both a class (created with ::new) and a default registry (loaded automatically or through interactions with #[] and #type_for).
The Default mime-types Registry¶ ↑
The default mime-types registry is loaded automatically when the library is
required (require 'mime/types'
), but it may be lazily
loaded (loaded on first use) with the use of the environment variable
RUBY_MIME_TYPES_LAZY_LOAD
having any value other than
false
. The initial startup is about 14× faster (~10 ms vs ~140
ms), but the registry will be loaded at some point in the future.
The default mime-types registry can also be loaded from a Marshal cache
file specific to the version of MIME::Types being
loaded. This will be handled automatically with the use of a file referred
to in the environment variable RUBY_MIME_TYPES_CACHE
. MIME::Types will attempt to load the registry from
this cache file (MIME::Type::Cache.load); if it cannot be loaded (because
the file does not exist, there is an error, or the data is for a different
version of mime-types), the default registry will be loaded from the normal
JSON version and then the cache file will be written to
the location indicated by RUBY_MIME_TYPES_CACHE
. Cache file
loads just over 4½× faster (~30 ms vs ~140 ms). loads.
Notes:
-
The loading of the default registry is not atomic; when using a multi-threaded environment, it is recommended that lazy loading is not used and mime-types is loaded as early as possible.
-
Cache files should be specified per application in a multiprocess environment and should be initialized during deployment or before forking to minimize the chance that the multiple processes will be trying to write to the same cache file at the same time, or that two applications that are on different versions of mime-types would be thrashing the cache.
-
Unless cache files are preinitialized, the application using the mime-types cache file must have read/write permission to the cache file.
Usage¶ ↑
require 'mime/types' plaintext = MIME::Types['text/plain'] print plaintext.media_type # => 'text' print plaintext.sub_type # => 'plain' puts plaintext.extensions.join(" ") # => 'asc txt c cc h hh cpp' puts plaintext.encoding # => 8bit puts plaintext.binary? # => false puts plaintext.ascii? # => true puts plaintext.obsolete? # => false puts plaintext.registered? # => true puts plaintext.provisional? # => false puts plaintext == 'text/plain' # => true puts MIME::Type.simplified('x-appl/x-zip') # => 'appl/zip'
Constants
- VERSION
The release version of Ruby MIME::Types
Attributes
Configure the MIME::Types logger. This defaults to an instance of a logger that passes messages (unformatted) through to Kernel#warn.
Public Class Methods
#[] against the default MIME::Types registry.
# File lib/mime/types/registry.rb, line 13 def [](type_id, complete: false, registered: false) __types__[type_id, complete: complete, registered: registered] end
#add against the default MIME::Types registry.
# File lib/mime/types/registry.rb, line 38 def add(*types) __types__.add(*types) end
#count against the default MIME::Types registry.
# File lib/mime/types/registry.rb, line 18 def count __types__.count end
#each against the default MIME::Types registry.
# File lib/mime/types/registry.rb, line 23 def each if block_given? __types__.each { |t| yield t } else enum_for(:each) end end
Creates a new MIME::Types registry.
# File lib/mime/types.rb, line 74 def initialize @type_variants = Container.new @extension_index = Container.new end
#type_for against the default MIME::Types registry.
# File lib/mime/types/registry.rb, line 32 def type_for(filename) __types__.type_for(filename) end
Private Class Methods
# File lib/mime/types/registry.rb, line 74 def __instances__ @__instances__ ||= Set.new end
# File lib/mime/types/registry.rb, line 54 def __types__ (defined?(@__types__) && @__types__) || load_default_mime_types end
# File lib/mime/types/registry.rb, line 44 def lazy_load? return unless ENV.key?("RUBY_MIME_TYPES_LAZY_LOAD") MIME::Types.logger.warn <<-WARNING.chomp.strip Lazy loading ($RUBY_MIME_TYPES_LAZY_LOAD) is deprecated and will be removed. WARNING (lazy = ENV["RUBY_MIME_TYPES_LAZY_LOAD"]) && (lazy != "false") end
# File lib/mime/types/registry.rb, line 64 def load_default_mime_types(mode = load_mode) if (@__types__ = MIME::Types::Cache.load) __instances__.add(@__types__) else @__types__ = MIME::Types::Loader.load(mode) MIME::Types::Cache.save(@__types__) end @__types__ end
# File lib/mime/types/full.rb, line 10 def load_mode {columnar: false} end
# File lib/mime/types/registry.rb, line 78 def reindex_extensions(type) __instances__.each do |instance| instance.send(:reindex_extensions!, type) end true end
Public Instance Methods
Returns a list of MIME::Type objects, which may be
empty. The optional flag parameters are :complete
(finds only
complete MIME::Type objects) and
:registered
(finds only MIME::Types
that are registered). It is possible for multiple matches to be returned
for either type (in the example below, 'text/plain' returns two
values – one for the general case, and one for VMS systems).
puts "\nMIME::Types['text/plain']" MIME::Types['text/plain'].each { |t| puts t.to_a.join(", ") } puts "\nMIME::Types[/^image/, complete: true]" MIME::Types[/^image/, :complete => true].each do |t| puts t.to_a.join(", ") end
If multiple type definitions are returned, returns them sorted as follows:
1. Complete definitions sort before incomplete ones; 2. IANA-registered definitions sort before LTSW-recorded definitions. 3. Current definitions sort before obsolete ones; 4. Obsolete definitions with use-instead clauses sort before those without; 5. Obsolete definitions use-instead clauses are compared. 6. Sort on name.
# File lib/mime/types.rb, line 124 def [](type_id, complete: false, registered: false) matches = case type_id when MIME::Type @type_variants[type_id.simplified] when Regexp match(type_id) else @type_variants[MIME::Type.simplified(type_id)] end prune_matches(matches, complete, registered).sort { |a, b| a.priority_compare(b) } end
Add one or more MIME::Type objects to the set of known types. If the type is already known, a warning will be displayed.
The last parameter may be the value :silent
or
true
which will suppress duplicate MIME type warnings.
# File lib/mime/types.rb, line 166 def add(*types) quiet = ((types.last == :silent) || (types.last == true)) types.each do |mime_type| case mime_type when true, false, nil, Symbol nil when MIME::Types variants = mime_type.instance_variable_get(:@type_variants) add(*variants.values.inject(Set.new, :+).to_a, quiet) when Array add(*mime_type, quiet) else add_type(mime_type, quiet) end end end
Add a single MIME::Type object to the set of known
types. If the type
is already known, a warning will be
displayed. The quiet
parameter may be a truthy value to
suppress that warning.
# File lib/mime/types.rb, line 187 def add_type(type, quiet = false) if !quiet && @type_variants[type.simplified].include?(type) MIME::Types.logger.warn <<-WARNING.chomp.strip Type #{type} is already registered as a variant of #{type.simplified}. WARNING end add_type_variant!(type) index_extensions!(type) end
Returns the number of known type variants.
# File lib/mime/types.rb, line 80 def count @type_variants.values.inject(0) { |a, e| a + e.size } end
Iterates through the type variants.
# File lib/mime/types.rb, line 89 def each if block_given? @type_variants.each_value { |tv| tv.each { |t| yield t } } else enum_for(:each) end end
Return the list of MIME::Types which belongs to the file based on its filename extension. If there is no extension, the filename will be used as the matching criteria on its own.
This will always return a merged, flatten, priority sorted, unique array.
puts MIME::Types.type_for('citydesk.xml') => [application/xml, text/xml] puts MIME::Types.type_for('citydesk.gif') => [image/gif] puts MIME::Types.type_for(%w(citydesk.xml citydesk.gif)) => [application/xml, image/gif, text/xml]
# File lib/mime/types.rb, line 152 def type_for(filename) Array(filename).flat_map { |fn| @extension_index[fn.chomp.downcase[/\.?([^.]*?)$/, 1]] }.compact.inject(Set.new, :+).sort { |a, b| a.priority_compare(b) } end
Private Instance Methods
# File lib/mime/types.rb, line 200 def add_type_variant!(mime_type) @type_variants.add(mime_type.simplified, mime_type) end
# File lib/mime/types.rb, line 210 def index_extensions!(mime_type) mime_type.extensions.each { |ext| @extension_index.add(ext, mime_type) } end
# File lib/mime/types.rb, line 220 def match(pattern) @type_variants.select { |k, _| k =~ pattern }.values.inject(Set.new, :+) end
# File lib/mime/types.rb, line 214 def prune_matches(matches, complete, registered) matches.delete_if { |e| !e.complete? } if complete matches.delete_if { |e| !e.registered? } if registered matches end
# File lib/mime/types.rb, line 204 def reindex_extensions!(mime_type) return unless @type_variants[mime_type.simplified].include?(mime_type) index_extensions!(mime_type) end