The Identity Card a Single Page Carries
Give one page its own title, author, subject and dates, so a document cut back into pieces keeps each piece's identity.
See It in a Real PDF
A File That Explains Its Own Entries
A records office's reference, the department it came from, the date until which the document must be kept and its classification, carried inside a file an archive still accepts. No archiving rule knows what a keep-until date is, so each entry carries a description of itself, and that description is what makes a checker accept a fact you alone invented. A second page adds a loan record whose entries are a yes or no, a type of file, a person's name, a measurement and two web addresses, and gives that page a hidden record of its own.
Open the PDF The Whole Example
Also shown in: A Register Whose Pages Say Where They Came From
Summary
A document has an identity card: a title, an author, a subject, a date. When one PDF holds a hundred separate things — a register of sittings, a run of statements — one card for the whole is not enough, because the hundred were written by different hands on different days. It is the same information as the document's own card, written for one page instead of for all of them.
Technically
Written at the top level of a request, under
"page_metadata"
page_metadata writes an XMP /Metadata packet on the page itself, in the same shape as the document's. Two forms are accepted: facts, the fields written out — title, author, subject, keywords, the dates — from which the packet is built; or packet, a packet already written, carried across as it stands. A page named twice takes the last packet given for it. The document's own packet is untouched: this adds a card to a page, it does not replace the one on the front.
Request Schema
-
page_metadata— array, optional, empty by default. -
page_metadata[].page— integer, required, counting from 1, as every page number in a request counts. -
page_metadata[].metadata— object, required. Eitherfacts, an object of the fields the document's own card takes (title,author,subject,keywords,created,modified), orpacket, a packet already written and carried across unchanged.
Scope: the pages named. A page named twice takes the last packet given for it. metadata settles the document's own card and is not touched by this.
A Whole Request That Creates a PDF
{
"page_metadata": [
{
"page": 1,
"metadata": {
"facts": {
"title": "First sitting",
"author": "R. Delaunay, clerk",
"subject": "One sitting of the register",
"created": "1911-03-14T09:00:00+01:00"
}
}
}
],
"standard_fonts": [{ "name": "sans", "face": "helvetica" }],
"items": [
{
"type": "text",
"rect": { "llx": 72, "lly": 700, "urx": 523, "ury": 740 },
"content": ["A page carrying an identity card of its own"],
"font": "sans",
"font_size": 12
}
]
}The document as a whole
The Numbers Reading Software Shows A Hundred Letters in a Single File What the Document Says about Itself What the Document Says about Itself, Said Once Text Nobody Can Copy The Notes a Program Leaves in the File for Itself The Notes a Program Leaves on One Page The Data a Program Hangs on a Run of Ink A File Still Readable Decades from Now The Print Standard the Document Claims The Variable Print Standard the Document Claims The Password That Opens It, and What May Be Done with It An Invoice a Person and a Machine Both Read The Address Relative Links Are Read Against The PDF Version the File Declares The Extensions to PDF the File Says It Uses What a Picture Says about Itself, and How It Is Read The Attachments the Document Carries Beside Its Pages Files the Document Names without Carrying The Attachments Shown as a Portfolio Which Attachments a Page Claims Which Attachments a Font Claims The Identity Card a Single Font Carries Which Attachments the Document's Card Claims A Document Card Written Elsewhere The Areas of a Page a Reader Measures In The Accessibility Standard the Document Claims The Standards the Finished Document Is Measured Against
Where to Go Next
Every JSON key of a request, in one page The other forty-one settings of a request