rfc2731.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

   Contributor (other entity that made a contribution)
   -----------

    <meta name    = "DC.Contributor"
          content = "Curie, Marie">

    <meta name    = "DC.Contributor.Photographer"
          content = "Adams, Ansel">
    <meta name    = "DC.Contributor.Artist"
          content = "Sendak, Maurice">
    <meta name    = "DC.Contributor.Editor"
          content = "Starr, Kenneth">





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   Date (of an event in the life of the resource; [WTN8601] recommended)
   ----

    <meta name    = "DC.Date"
          content = "1972">

    <meta name    = "DC.Date"
          content = "1998-05-14">
    <meta name    = "DC.Date"
          scheme  = "WTN8601"
          content = "1998-05-14">

    <meta name    = "DC.Date.Created"
          content = "1998-05-14">
    <meta name    = "DC.Date.Available"
          content = "1998-05-21">
    <meta name    = "DC.Date.Valid"
          content = "1998-05-28">

    <meta name    = "DC.Date.Created"
          content = "triassic">
    <meta name    = "DC.Date.Acquired"
          content = "1957">

    <meta name    = "DC.Date.Accepted"
          scheme  = "WTN8601"
          content = "1998-12-02T16:59">

    <meta name    = "DC.Date.DataGathered"
          scheme  = "ISO8601"
          content = "98-W49-3T1659">

    <meta name    = "DC.Date.Issued"
          scheme  = "ANSI.X3.X30-1985"
          content = "19980514">

   Type (nature, genre, or category; [DCT1] recommended)
   ----

    <meta name    = "DC.Type"
          content = "poem">

    <meta name    = "DC.Type"
          scheme  = "DCT1"
          content = "software">
    <meta name    = "DC.Type"
          content = "software program source code">




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    <meta name    = "DC.Type"
          content = "interactive video game">

    <meta name    = "DC.Type"
          scheme  = "DCT1"
          content = "dataset">

    <meta name    = "DC.Type"
          content = "web home page">
    <meta name    = "DC.Type"
          content = "web bibliography">

    <meta name    = "DC.Type"
          content = "painting">
    <meta name    = "DC.Type"
          content = "image; woodblock">
    <meta name    = "DC.Type"
          scheme  = "AAT"
          content = "clipeus (portrait)">
    <meta name    = "DC.Type"
          lang    = "en-US"
          content = "image; advertizement">

    <meta name    = "DC.Type"
          scheme  = "DCT1"
          content = "event">
    <meta name    = "DC.Type"
          content = "event; periodic">

   Format (physical or digital data format, plus optional dimensions)
   ------

    <meta name    = "DC.Format"
          content = "text/xml">
    <meta name    = "DC.Format"
          scheme  = "IMT"
          content = "text/xml">

    <meta name    = "DC.Format"
          scheme  = "IMT"
          content = "image/jpeg">
    <meta name    = "DC.Format"
          content = "A text file with mono-spaced tables and diagrams.">

    <meta name    = "DC.Format"
          content = "video/mpeg; 14 minutes">





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    <meta name    = "DC.Format"
          content = "unix tar archive, gzip compressed; 1.5 Mbytes">

    <meta name    = "DC.Format"
          content = "watercolor; 23 cm x 31 cm">

   Identifier (of the resource)
   ----------

    <meta name    = "DC.Identifier"
          content = "http://foo.bar.org/zaf/">

    <meta name    = "DC.Identifier"
          content = "urn:ietf:rfc:1766">

    <meta name    = "DC.Identifier"
          scheme  = "ISBN"
          content = "1-56592-149-6">

    <meta name    = "DC.Identifier"
          scheme  = "LCCN"
          content = "67-26020">

    <meta name    = "DC.Identifier"
          scheme  = "DOI"
          content = "10.12345/33-824688ab">

   Source (reference to the resource's origin)
   ------

    <meta name    = "DC.Source"
          content = "Shakespeare's Romeo and Juliet">

    <meta name    = "DC.Source"
          content = "http://a.b.org/manon/">

   Language (of the content of the resource; [RFC1766] recommended)
   --------

    <meta name    = "DC.Language"
          content = "en">
    <meta name    = "DC.Language"
          scheme  = "rfc1766"
          content = "en">
    <meta name    = "DC.Language"
          scheme  = "ISO639-2"
          content = "eng">




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    <meta name    = "DC.Language"
          scheme  = "rfc1766"
          content = "en-US">

    <meta name    = "DC.Language"
          content = "zh">
    <meta name    = "DC.Language"
          content = "ja">
    <meta name    = "DC.Language"
          content = "es">
    <meta name    = "DC.Language"
          content = "de">

    <meta name    = "DC.Language"
          content = "german">
    <meta name    = "DC.Language"
          lang    = "fr"
          content = "allemand">

   Relation (reference to a related resource)
   --------

    <meta name    = "DC.Relation.IsPartOf"
          content = "http://foo.bar.org/abc/proceedings/1998/">

    <meta name    = "DC.Relation.IsFormatOf"
          content = "http://foo.bar.org/cd145.sgml">

    <meta name    = "DC.Relation.IsVersionOf"
          content = "http://foo.bar.org/draft9.4.4.2">

    <meta name    = "DC.Relation.References"
          content = "urn:isbn:1-56592-149-6">

    <meta name    = "DC.Relation.IsBasedOn"
          content = "Shakespeare's Romeo and Juliet">

    <meta name    = "DC.Relation.Requires"
          content = "LWP::UserAgent; HTML::Parse; URI::URL;
                     Net::DNS; Tk::Pixmap; Tk::Bitmap; Tk::Photo">

   Coverage (extent or scope of the content)
   --------

    <meta name    = "DC.Coverage"
          content = "US civil war era; 1861-1865">





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    <meta name    = "DC.Coverage"
          content = "Columbus, Ohio, USA; Lat: 39 57 N Long: 082 59 W">

    <meta name    = "DC.Coverage"
          scheme  = "TGN"
          content = "Columbus (C,V)">

    <meta name    = "DC.Coverage.Jurisdiction"
          content = "Commonwealth of Australia">

   Rights (text or identifier of a rights management statement)
   ------

    <meta name    = "DC.Rights"
          lang    = "en"
          content = "Copyright Acme 1999 - All rights reserved.">

    <meta name    = "DC.Rights"
          content = "http://foo.bar.org/cgi-bin/terms">

8. Security Considerations

   The syntax rules for encoding Dublin Core metadata in HTML that are
   documented here pose no direct risk to computers and networks.
   People can use these rules to encode metadata that is inaccurate or
   even deliberately misleading (creating mischief in the form of "index
   spam"), however, this reflects a general pattern of HTML META tag
   abuse that is not limited to the encoding of metadata from the Dublin
   Core set.  Even traditional metadata encoding schemes (e.g., [MARC])
   are not immune to inaccuracy, although they are generally followed in
   environments where production quality greatly exceeds that of the
   average Web site.

   Systems that process metadata encoded with META tags need to consider
   issues related to its accuracy and validity as part of their design
   and implementation, and users of such systems need to consider the
   design and implementation assumptions.  Various approaches may be
   relevant for certain applications, such as adding statements of
   metadata provenance, signing of metadata with digital signatures, and
   automating certain aspects of metadata creation; but these are far
   outside the scope of this document and the underlying META tag syntax
   that it describes.









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9. Appendix -- Perl Scripts that Manipulate HTML Encoded Metadata

   This section contains two simple programs that work with versions 4
   and 5 of the Perl [PERL] scripting language interpreter.  They may be
   taken and freely adapted for local organizational needs, research
   proposals, venture capital bids, etc.  A variety of applications are
   within easy reach of implementors that choose to build on these
   scripts.

   Script 1:  Metadata Format Conversion
   -------------------------------------

   Here is a simple Perl script that correctly recognizes every example
   of metadata encoding in this document.  It shows how a modest
   scripting effort can produce a utility that converts metadata from
   one format to another.  Minor changes are sufficient to support a
   number of output formats.

#!/depot/bin/perl
#
# This simple perl script extracts metadata embedded in an HTML file
# and outputs it in an alternate format.  Issues warning about missing
# element name or value.
#
# Handles mixed case tags and attribute values, one per line or spanning
# several lines.  Also handles a quoted string spanning multiple lines.
# No error checking.  Does not tolerate more than one "<meta" per line.

print "@(urc;\n";
while (<>) {
        next if (! /<meta/i);
        ($meta) = /(<meta.*$)/i;
        if (! /<meta.*>/i) {
                while (<>) {
                        $meta .= $_;
                        last if (/>/);
                }
        }
        $name     =    $meta =~ /name\s*=\s*"([^"]*)"/i
                        ? $1 : "MISSING ELEMENT NAME";
        $content  = $meta =~ /content\s*=\s*"([^"]*)"/i
                        ? $1 : "MISSING ELEMENT VALUE";
        ($scheme) =  $meta =~ /scheme\s*=\s*"([^"]*)"/i;
        ($lang)   =    $meta =~ /lang\s*=\s*"([^"]*)"/i;

        if ($lang || $scheme) {
                $mod = " ($lang";
                if (! $scheme)



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                        { $mod .= ")"; }
                elsif (! $lang)
                        { $mod .= "$scheme)" }
                else
                        { $mod .= ", $scheme)"; }
        }
        else
                { $mod = ""; }

        print "    @|$name$mod; $content\n";
}
print "@)urc;\n";
# ---- end of Perl script ----

   When the conversion script is run on the metadata file example from
   the LINK tag section (section 4), it produces the following output.

        @(urc;
            @|DC.Title; A Dirge
            @|DC.Creator; Shelley, Percy Bysshe
            @|DC.Type; poem
            @|DC.Date; 1820
            @|DC.Format; text/html
            @|DC.Language; en
        @)urc;

   Script 2:  Automated Metadata Creation
   --------------------------------------

   The creation and maintenance of high-quality metadata can be
   extremely expensive without automation to assist in processes such as
   supplying pre-set or computed defaults, validating syntax, verifying
   value ranges, spell checking, etc.  Considerable relief could be had
   from a script that reduced an individual provider's metadata burden
   to just the title of each document.  Below is such a script.  It lets
   the provider of an HTML document abbreviate an entire embedded
   resource description using a single HTML comment statement that looks
   like

       <!--metablock Little Red Riding Hood -->

   Our script processes this statement specially as a kind of "metadata
   block" declaration with attached title.  The general form is

       <!--metablock TITLE_OF_DOCUMENT -->






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   This statement works much like a "Web server-side include" in that
   the script replaces it with a fully-specified block of metadata and
   triggers other replacements.  Once installed, the script can output
   HTML files suitable for integration into one's production Web server
   procedures.

   The individual provider keeps a separate "template" file of
   infrequently changing pre-set values for metadata elements.  If the
   provider's needs are simple enough, the only element values besides
   the title that differ from one document to the next may be generated
   automatically.  Using the script, values may be referenced as
   variables from within the template or within the document.  Our
   variable references have the form "(--mbVARNAME)", and here is what
   they look like inside a template:

       <title> (--mbtitle) </title>