# class MIME::Multipart::Builder

- MIME::Multipart::Builder
- Reference
- Object

##
Overview

Builds a multipart MIME message.

###
Example

    require "mime/multipart"

    io = IO::Memory.new # This is a stub. Actually, any IO can be used.
    multipart = MIME::Multipart::Builder.new(io)
    multipart.body_part HTTP::Headers{"Content-Type" => "text/plain"}, "hello!"
    multipart.finish
    io.to_s # => "----------------------------DTf61dRTHYzprx7rwVQhTWr7\r\nContent-Type: text/plain\r\n\r\nhello!\r\n----------------------------DTf61dRTHYzprx7rwVQhTWr7--"

##
Defined in:

mime/multipart/builder.cr

##
Constructors

- .new(io : IO, boundary : String = Multipart.generate_boundary)

  Creates a new `Multipart::Builder` which writes the generated multipart message to io, using the multipart boundary boundary.

##
Instance Method Summary

- #body_part(headers : HTTP::Headers, string : String) : Nil

  Appends a body part to the multipart message with the given headers and string.

- #body_part(headers : HTTP::Headers, data : Bytes) : Nil

  Appends a body part to the multipart message with the given headers and data.

- #body_part(headers : HTTP::Headers, body_io : IO) : Nil

  Appends a body part to the multipart message with the given headers and data from body_io.

- #body_part(headers : HTTP::Headers, &)

  Yields an IO that can be used to write to a body part which is appended to the multipart message with the given headers.

- #body_part(headers : HTTP::Headers) : Nil

  Appends a body part to the multipart message with the given headers and no body data.

- #boundary : String
- #content_type(subtype : String = "mixed") : String

  Returns a content type header with multipart subtype subtype, and boundary parameter added.

- #epilogue(string : String) : Nil

  Appends string to the epilogue segment of the multipart message.

- #epilogue(data : Bytes) : Nil

  Appends data to the epilogue segment of the multipart message.

- #epilogue(epilogue_io : IO) : Nil

  Appends preamble_io to the epilogue segment of the multipart message.

- #epilogue(&)

  Yields an IO that can be used to append to the epilogue of the multipart message.

- #finish : Nil

  Finalizes the multipart message, this method must be called to properly end the multipart message.

- #preamble(string : String) : Nil

  Appends string to the preamble segment of the multipart message.

- #preamble(data : Bytes) : Nil

  Appends data to the preamble segment of the multipart message.

- #preamble(preamble_io : IO) : Nil

  Appends preamble_io to the preamble segment of the multipart message.

- #preamble(&)

  Yields an IO that can be used to append to the preamble of the multipart message.

### Instance methods inherited from class `Reference`

==(other : self)
==(other : JSON::Any)
==(other : YAML::Any)
==(other) ==, dup dup, hash(hasher) hash, initialize initialize, inspect(io : IO) : Nil inspect, object_id : UInt64 object_id, pretty_print(pp) : Nil pretty_print, same?(other : Reference) : Bool
same?(other : Nil) same?, to_s(io : IO) : Nil to_s

### Constructor methods inherited from class `Reference`

new new, unsafe_construct(address : Pointer, *args, **opts) : self unsafe_construct

### Class methods inherited from class `Reference`

pre_initialize(address : Pointer) pre_initialize

### Instance methods inherited from class `Object`

! : Bool !, !=(other) !=, !~(other) !~, ==(other) ==, ===(other : JSON::Any)
===(other : YAML::Any)
===(other) ===, =~(other) =~, as(type : Class) as, as?(type : Class) as?, class class, dup dup, hash(hasher)
hash hash, in?(collection : Object) : Bool
in?(*values : Object) : Bool in?, inspect(io : IO) : Nil
inspect : String inspect, is_a?(type : Class) : Bool is_a?, itself itself, nil? : Bool nil?, not_nil!(message)
not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, responds_to?(name : Symbol) : Bool responds_to?, tap(&) tap, to_json(io : IO) : Nil
to_json : String to_json, to_pretty_json(indent : String = " ") : String
to_pretty_json(io : IO, indent : String = " ") : Nil to_pretty_json, to_s(io : IO) : Nil
to_s : String to_s, to_yaml(io : IO) : Nil
to_yaml : String to_yaml, try(&) try, unsafe_as(type : T.class) forall T unsafe_as

### Class methods inherited from class `Object`

from_json(string_or_io : String | IO, root : String)
from_json(string_or_io : String | IO) from_json, from_yaml(string_or_io : String | IO) from_yaml

### Macros inherited from class `Object`

class_getter(*names, &block) class_getter, class_getter!(*names) class_getter!, class_getter?(*names, &block) class_getter?, class_property(*names, &block) class_property, class_property!(*names) class_property!, class_property?(*names, &block) class_property?, class_setter(*names) class_setter, def_clone def_clone, def_equals(*fields) def_equals, def_equals_and_hash(*fields) def_equals_and_hash, def_hash(*fields) def_hash, delegate(*methods, to object) delegate, forward_missing_to(delegate) forward_missing_to, getter(*names, &block) getter, getter!(*names) getter!, getter?(*names, &block) getter?, property(*names, &block) property, property!(*names) property!, property?(*names, &block) property?, setter(*names) setter

##
Constructor Detail

def self.new(io : IO, boundary : String = Multipart.generate_boundary) #

Creates a new `Multipart::Builder` which writes the generated multipart message to io, using the multipart boundary boundary.

##
Instance Method Detail

def body_part(headers : HTTP::Headers, string : String) : Nil #

Appends a body part to the multipart message with the given headers and string. Throws if `#finish` or `#epilogue` is called before this method.

def body_part(headers : HTTP::Headers, data : Bytes) : Nil #

Appends a body part to the multipart message with the given headers and data. Throws if `#finish` or `#epilogue` is called before this method.

def body_part(headers : HTTP::Headers, body_io : IO) : Nil #

Appends a body part to the multipart message with the given headers and data from body_io. Throws if `#finish` or `#epilogue` is called before this method.

def body_part(headers : HTTP::Headers, &) #

Yields an IO that can be used to write to a body part which is appended to the multipart message with the given headers. Throws if `#finish` or `#epilogue` is called before this method.

def body_part(headers : HTTP::Headers) : Nil #

Appends a body part to the multipart message with the given headers and no body data. Throws is `#finish` or `#epilogue` is called before this method.

def boundary : String #
def content_type(subtype : String = "mixed") : String #

Returns a content type header with multipart subtype subtype, and boundary parameter added.

    require "mime/multipart"

    io = IO::Memory.new # This is a stub. Actually, any IO can be used.
    builder = MIME::Multipart::Builder.new(io, "a4VF")
    builder.content_type("mixed") # => "multipart/mixed; boundary=a4VF"

def epilogue(string : String) : Nil #

Appends string to the epilogue segment of the multipart message. Throws if `#finish` is called before this method, or no body parts have been appended.

Can be called multiple times to append to the epilogue multiple times.

def epilogue(data : Bytes) : Nil #

Appends data to the epilogue segment of the multipart message. Throws if `#finish` is called before this method, or no body parts have been appended.

Can be called multiple times to append to the epilogue multiple times.

def epilogue(epilogue_io : IO) : Nil #

Appends preamble_io to the epilogue segment of the multipart message. Throws if `#finish` is called before this method, or no body parts have been appended.

Can be called multiple times to append to the epilogue multiple times.

def epilogue(&) #

Yields an IO that can be used to append to the epilogue of the multipart message. Throws if `#finish` is called before this method, or no body parts have been appended.

Can be called multiple times to append to the preamble multiple times.

def finish : Nil #

Finalizes the multipart message, this method must be called to properly end the multipart message.

def preamble(string : String) : Nil #

Appends string to the preamble segment of the multipart message. Throws if `#body_part` is called before this method.

Can be called multiple times to append to the preamble multiple times.

def preamble(data : Bytes) : Nil #

Appends data to the preamble segment of the multipart message. Throws if `#body_part` is called before this method.

Can be called multiple times to append to the preamble multiple times.

def preamble(preamble_io : IO) : Nil #

Appends preamble_io to the preamble segment of the multipart message. Throws if `#body_part` is called before this method.

Can be called multiple times to append to the preamble multiple times.

def preamble(&) #

Yields an IO that can be used to append to the preamble of the multipart message. Throws if `#body_part` is called before this method.

Can be called multiple times to append to the preamble multiple times.