# NAME

HTTP::Message - HTTP style message (base class)

# VERSION

version 7.01

# SYNOPSIS

    use parent 'HTTP::Message';

# DESCRIPTION

An `HTTP::Message` object contains some headers and a content body.
The following methods are available:

- $mess = HTTP::Message->new
- $mess = HTTP::Message->new( $headers )
- $mess = HTTP::Message->new( $headers, $content )

    This constructs a new message object.  Normally you would want
    construct `HTTP::Request` or `HTTP::Response` objects instead.

    The optional $header argument should be a reference to an
    `HTTP::Headers` object or a plain array reference of key/value pairs.
    If an `HTTP::Headers` object is provided then a copy of it will be
    embedded into the constructed message, i.e. it will not be owned and
    can be modified afterwards without affecting the message.

    The optional $content argument should be a string of bytes.

- $mess = HTTP::Message->parse( $str )

    This constructs a new message object by parsing the given string.

- $mess->headers

    Returns the embedded `HTTP::Headers` object.

- $mess->headers\_as\_string
- $mess->headers\_as\_string( $eol )

    Call the as\_string() method for the headers in the
    message.  This will be the same as

        $mess->headers->as_string

    but it will make your program a whole character shorter :-)

- $mess->content
- $mess->content( $bytes )

    The content() method sets the raw content if an argument is given.  If no
    argument is given the content is not touched.  In either case the
    original raw content is returned.

    If the `undef` argument is given, the content is reset to its default value,
    which is an empty string.

    Note that the content should be a string of bytes.  Strings in perl
    can contain characters outside the range of a byte.  The `Encode`
    module can be used to turn such strings into a string of bytes.

- $mess->add\_content( $bytes )

    The add\_content() methods appends more data bytes to the end of the
    current content buffer.

- $mess->add\_content\_utf8( $string )

    The add\_content\_utf8() method appends the UTF-8 bytes representing the
    string to the end of the current content buffer.

- $mess->content\_ref
- $mess->content\_ref( \\$bytes )

    The content\_ref() method will return a reference to content buffer string.
    It can be more efficient to access the content this way if the content
    is huge, and it can even be used for direct manipulation of the content,
    for instance:

        ${$res->content_ref} =~ s/\bfoo\b/bar/g;

    This example would modify the content buffer in-place.

    If an argument is passed it will setup the content to reference some
    external source.  The content() and add\_content() methods
    will automatically dereference scalar references passed this way.  For
    other references content() will return the reference itself and
    add\_content() will refuse to do anything.

- $mess->content\_charset

    This returns the charset used by the content in the message.  The
    charset is either found as the charset attribute of the
    `Content-Type` header or by guessing.

    See [http://www.w3.org/TR/REC-html40/charset.html#spec-char-encoding](http://www.w3.org/TR/REC-html40/charset.html#spec-char-encoding)
    for details about how charset is determined.

- $mess->decoded\_content( %options )

    Returns the content with any `Content-Encoding` undone and, for textual content
    (`Content-Type` values starting with `text/`, exactly matching
    `application/xml`, or ending with `+xml`), the raw content's character set
    decoded into Perl's Unicode string format. Note that this
    [does not currently](https://github.com/libwww-perl/HTTP-Message/pull/99)
    attempt to decode declared character sets for any other content types like
    `application/json` or `application/javascript`.  If the `Content-Encoding`
    or `charset` of the message is unknown, this method will fail by returning
    `undef`.

    The following options can be specified.

    - `charset`

        This overrides the charset parameter for text content.  The value
        `none` can used to suppress decoding of the charset.

    - `default_charset`

        This overrides the default charset guessed by content\_charset() or
        if that fails "ISO-8859-1".

    - `alt_charset`

        If decoding fails because the charset specified in the Content-Type header
        isn't recognized by Perl's Encode module, then try decoding using this charset
        instead of failing.  The `alt_charset` might be specified as `none` to simply
        return the string without any decoding of charset as alternative.

    - `charset_strict`

        Abort decoding if malformed characters is found in the content.  By
        default you get the substitution character ("\\x{FFFD}") in place of
        malformed characters.

    - `raise_error`

        If TRUE then raise an exception if not able to decode content.  Reason
        might be that the specified `Content-Encoding` or `charset` is not
        supported.  If this option is FALSE, then decoded\_content() will return
        `undef` on errors, but will still set $@.

    - `ref`

        If TRUE then a reference to decoded content is returned.  This might
        be more efficient in cases where the decoded content is identical to
        the raw content as no data copying is required in this case.

- $mess->decodable
- HTTP::Message::decodable()

    This returns the encoding identifiers that decoded\_content() can
    process.  In scalar context returns a comma separated string of
    identifiers.

    This value is suitable for initializing the `Accept-Encoding` request
    header field.

- $mess->decode

    This method tries to replace the content of the message with the
    decoded version and removes the `Content-Encoding` header.  Returns
    TRUE if successful and FALSE if not.

    If the message does not have a `Content-Encoding` header this method
    does nothing and returns TRUE.

    Note that the content of the message is still bytes after this method
    has been called and you still need to call decoded\_content() if you
    want to process its content as a string.

- $mess->encode( $encoding, ... )

    Apply the given encodings to the content of the message.  Returns TRUE
    if successful. The "identity" (non-)encoding is always supported; other
    currently supported encodings, subject to availability of required
    additional modules, are "gzip", "deflate", "x-bzip2", "base64" and "br".

    A successful call to this function will set the `Content-Encoding`
    header.

    Note that `multipart/*` or `message/*` messages can't be encoded and
    this method will croak if you try.

- $mess->parts
- $mess->parts( @parts )
- $mess->parts( \\@parts )

    Messages can be composite, i.e. contain other messages.  The composite
    messages have a content type of `multipart/*` or `message/*`.  This
    method give access to the contained messages.

    The argumentless form will return a list of `HTTP::Message` objects.
    If the content type of $msg is not `multipart/*` or `message/*` then
    this will return the empty list.  In scalar context only the first
    object is returned.  The returned message parts should be regarded as
    read-only (future versions of this library might make it possible
    to modify the parent by modifying the parts).

    If the content type of $msg is `message/*` then there will only be
    one part returned.

    If the content type is `message/http`, then the return value will be
    either an `HTTP::Request` or an `HTTP::Response` object.

    If a @parts argument is given, then the content of the message will be
    modified. The array reference form is provided so that an empty list
    can be provided.  The @parts array should contain `HTTP::Message`
    objects.  The @parts objects are owned by $mess after this call and
    should not be modified or made part of other messages.

    When updating the message with this method and the old content type of
    $mess is not `multipart/*` or `message/*`, then the content type is
    set to `multipart/mixed` and all other content headers are cleared.

    This method will croak if the content type is `message/*` and more
    than one part is provided.

- $mess->add\_part( $part )

    This will add a part to a message.  The $part argument should be
    another `HTTP::Message` object.  If the previous content type of
    $mess is not `multipart/*` then the old content (together with all
    content headers) will be made part #1 and the content type made
    `multipart/mixed` before the new part is added.  The $part object is
    owned by $mess after this call and should not be modified or made part
    of other messages.

    There is no return value.

- $mess->clear

    Will clear the headers and set the content to the empty string.  There
    is no return value

- $mess->protocol
- $mess->protocol( $proto )

    Sets the HTTP protocol used for the message.  The protocol() is a string
    like `HTTP/1.0` or `HTTP/1.1`.

- $mess->clone

    Returns a copy of the message object.

- $mess->as\_string
- $mess->as\_string( $eol )

    Returns the message formatted as a single string.

    The optional $eol parameter specifies the line ending sequence to use.
    The default is "\\n".  If no $eol is given then as\_string will ensure
    that the returned string is newline terminated (even when the message
    content is not).  No extra newline is appended if an explicit $eol is
    passed.

- $mess->dump( %opt )

    Returns the message formatted as a string.  In void context print the string.

    This differs from `$mess->as_string` in that it escapes the bytes
    of the content so that it's safe to print them and it limits how much
    content to print.  The escapes syntax used is the same as for Perl's
    double quoted strings.  If there is no content the string "(no
    content)" is shown in its place.

    Options to influence the output can be passed as key/value pairs. The
    following options are recognized:

    - maxlength => $num

        How much of the content to show.  The default is 512.  Set this to 0
        for unlimited.

        If the content is longer then the string is chopped at the limit and
        the string "...\\n(### more bytes not shown)" appended.

    - no\_content => $str

        Replaces the "(no content)" marker.

    - prefix => $str

        A string that will be prefixed to each line of the dump.

All methods unknown to `HTTP::Message` itself are delegated to the
`HTTP::Headers` object that is part of every message.  This allows
convenient access to these methods.  Refer to [HTTP::Headers](https://metacpan.org/pod/HTTP%3A%3AHeaders) for
details of these methods:

    $mess->header( $field => $val )
    $mess->push_header( $field => $val )
    $mess->init_header( $field => $val )
    $mess->remove_header( $field )
    $mess->remove_content_headers
    $mess->header_field_names
    $mess->scan( \&doit )

    $mess->date
    $mess->expires
    $mess->if_modified_since
    $mess->if_unmodified_since
    $mess->last_modified
    $mess->content_type
    $mess->content_encoding
    $mess->content_length
    $mess->content_language
    $mess->title
    $mess->user_agent
    $mess->server
    $mess->from
    $mess->referer
    $mess->www_authenticate
    $mess->authorization
    $mess->proxy_authorization
    $mess->authorization_basic
    $mess->proxy_authorization_basic

# AUTHOR

Gisle Aas <gisle@activestate.com>

# COPYRIGHT AND LICENSE

This software is copyright (c) 1994 by Gisle Aas.

This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
