header

        # CGI.header

(from ruby core)
---
    header(options='text/html')

---

This method is an alias for #http_header, when HTML5 tag maker is
inactive.

NOTE: use #http_header to create HTTP header blocks, this alias is only
provided for backwards compatibility.

Using #header with the HTML5 tag maker will create a <header> element.


(This method is an alias for CGI#http_header.)

Create an HTTP header block as a string.

Includes the empty line that ends the header block.

`content_type_string`
:   If this form is used, this string is the `Content-Type`
`headers_hash`
:   A Hash of header values. The following header keys are recognized:

    type
:       The Content-Type header.  Defaults to "text/html"
    charset
:       The charset of the body, appended to the Content-Type header.
    nph
:       A boolean value.  If true, prepend protocol string and status
        code, and date; and sets default values for "server" and
        "connection" if not explicitly set.
    status
:       The HTTP status code as a String, returned as the Status header.
         The values are:

        OK
:           200 OK
        PARTIAL_CONTENT
:           206 Partial Content
        MULTIPLE_CHOICES
:           300 Multiple Choices
        MOVED
:           301 Moved Permanently
        REDIRECT
:           302 Found
        NOT_MODIFIED
:           304 Not Modified
        BAD_REQUEST
:           400 Bad Request
        AUTH_REQUIRED
:           401 Authorization Required
        FORBIDDEN
:           403 Forbidden
        NOT_FOUND
:           404 Not Found
        METHOD_NOT_ALLOWED
:           405 Method Not Allowed
        NOT_ACCEPTABLE
:           406 Not Acceptable
        LENGTH_REQUIRED
:           411 Length Required
        PRECONDITION_FAILED
:           412 Precondition Failed
        SERVER_ERROR
:           500 Internal Server Error
        NOT_IMPLEMENTED
:           501 Method Not Implemented
        BAD_GATEWAY
:           502 Bad Gateway
        VARIANT_ALSO_VARIES
:           506 Variant Also Negotiates


    server
:       The server software, returned as the Server header.
    connection
:       The connection type, returned as the Connection header (for
        instance, "close".
    length
:       The length of the content that will be sent, returned as the
        Content-Length header.
    language
:       The language of the content, returned as the Content-Language
        header.
    expires
:       The time on which the current content expires, as a `Time`
        object, returned as the Expires header.
    cookie
:       A cookie or cookies, returned as one or more Set-Cookie headers.
         The value can be the literal string of the cookie; a
        CGI::Cookie object; an Array of literal cookie strings or Cookie
        objects; or a hash all of whose values are literal cookie
        strings or Cookie objects.

        These cookies are in addition to the cookies held in the
        @output_cookies field.


    Other headers can also be set; they are appended as key: value.


Examples:

    http_header
      # Content-Type: text/html

    http_header("text/plain")
      # Content-Type: text/plain

    http_header("nph"        => true,
                "status"     => "OK",  # == "200 OK"
                  # "status"     => "200 GOOD",
                "server"     => ENV['SERVER_SOFTWARE'],
                "connection" => "close",
                "type"       => "text/html",
                "charset"    => "iso-2022-jp",
                  # Content-Type: text/html; charset=iso-2022-jp
                "length"     => 103,
                "language"   => "ja",
                "expires"    => Time.now + 30,
                "cookie"     => [cookie1, cookie2],
                "my_header1" => "my_value",
                "my_header2" => "my_value")

This method does not perform charset conversion.