Supply EPUB Metadata

7.3.10.4 Supply EPUB Metadata

As an extension to the original Markdown spec from John Gruber, the content for the metadata section of an EPUB opf file may be provided following the literal {:metadata} on a line by itself, as in the following example:

{:metadata}
		<dc:identifier id="pub-identifier">notenik.app/kb</dc:identifier>
		<dc:title id="pub-title">The Notenik Knowledge Base</dc:title>
		<dc:creator id="author">Herb Bowie</dc:creator>
		<dc:language id="pub-language">en</dc:language>
		<meta property="dcterms:modified">2023-04-13T12:00:00Z</meta>

Note that the metadata elements shown above are considered mandatory in order to create a valid EPUB.

The content following this command within the body of the current Note will be used as the publication metadata when using the Export as Web Book function to create an actual EPUB file.

This command should appear as the first line within the body of a Note, and the remainder of the body will be used, in its entirety, and without further parsting, as the content appearing in the metadata element for a generated EPUB opf file.

A Note containing this command may appear anywhere within a Collection, and be given any convenient and meaningful title.

See the EPUB Metadata Note within the Notenik Knowledge Base for an example.

Since a Note containing such a command is not meant to be read sequentially as part of the overall Collection, Notenik will generally skip such pages when formatting Streamlined Reading navigational elements.

Varying the modified date

Note that the dcterms:modified value is used as part of the key to form a unique identifier for an ebook. So if you have multiple copies of the same book, and this date-and-time value does not change, then e-book readers such as Apple Books will not be able to distinguish between them (and may in fact refuse to import something it considers a duplicate).

In order to avoid such duplicates, the user may wish to replace a line like the one above – containing a fixed value – with something like the line below:

	<meta property="dcterms:modified">=$today&yyyy-MM-dd'T'HH:mm:ss'Z'$=</meta>

Notenik will then replace the =$today&yyyy-MM-dd'T'HH:mm:ss'Z'$= string with the properly formatted current date and time, as part of the EPUB export operation.

Next: 8. Files and Folders