1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446 | {
"archive": "pdfa3b",
"metadata": {
"title": "Records office cover sheet RO-2026-004318",
"author": "Olivier Pons",
"subject": "An archival sheet carrying metadata of its own",
"keywords": "archive, planning, retention",
"producer": "hqf-pdf",
"created": "2026-07-14T09:30:00+02:00",
"modified": "2026-09-17T14:05:00+02:00",
"schemas": [
{
"name": "Records Office Schema",
"namespace": "https://hqf-pdf.example/ns/records/1.0/",
"prefix": "rec",
"properties": [
{
"name": "Reference",
"value": "RO-2026-004318",
"description": "The reference the records office files the dossier under",
"value_type": "text",
"category": "external"
},
{
"name": "Department",
"value": "Planning",
"description": "The department the dossier came from",
"value_type": "text",
"category": "external"
},
{
"name": "RetainUntil",
"value": "2056-12-31T23:59:59+01:00",
"description": "The date the dossier may be destroyed, and not before",
"value_type": "date",
"category": "internal"
},
{
"name": "Classification",
"value": "Public",
"description": "How widely the dossier may be circulated",
"value_type": "text",
"category": "external"
},
{
"name": "Sheets",
"value": "1",
"description": "How many sheets the dossier holds",
"value_type": "integer",
"category": "internal"
}
]
},
{
"name": "Loan Record Schema",
"namespace": "https://hqf-pdf.example/ns/loans/1.0/",
"prefix": "loan",
"properties": [
{
"name": "Sealed",
"value": "True",
"description": "Whether the dossier left the office sealed",
"value_type": "boolean"
},
{
"name": "Format",
"value": "application/pdf",
"description": "The media type the dossier is lent in",
"value_type": "mime_type"
},
{
"name": "Custodian",
"value": "HQF Development",
"description": "Who holds the dossier while it is out",
"value_type": "proper_name"
},
{
"name": "ShelfMetres",
"value": "1.5",
"description": "How much shelf the dossier takes, in metres",
"value_type": "real"
},
{
"name": "Series",
"value": "https://hqf-pdf.com/records/series/42",
"description": "The series the dossier belongs to",
"value_type": "uri"
},
{
"name": "Catalogue",
"value": "https://hqf-pdf.com/records/catalogue",
"description": "Where the office's catalogue is read",
"value_type": "url"
},
{
"name": "Witnesses",
"value": {
"bag": [
"Claire Martin",
"Jan de Vries"
]
},
"description": "Who witnessed the loan",
"value_type": {
"bag": "proper_name"
}
},
{
"name": "Movements",
"value": {
"seq": [
{
"structure": [
{
"field": "When",
"value": "2026-09-01"
},
{
"field": "Holder",
"value": "Claire Martin"
}
]
},
{
"structure": [
{
"field": "When",
"value": "2026-09-17"
},
{
"field": "Holder",
"value": "HQF Development"
}
]
}
]
},
"description": "Each time the dossier changed hands, in order",
"value_type": {
"seq": {
"name": "Movement",
"namespace": "https://hqf-pdf.example/ns/loans/movement/1.0/",
"prefix": "mvt",
"description": "One change of hands of a dossier",
"fields": [
{
"name": "When",
"value_type": "date",
"description": "The day the dossier changed hands"
},
{
"name": "Holder",
"value_type": "proper_name",
"description": "Who took the dossier"
}
]
}
}
},
{
"name": "Conditions",
"value": {
"lang_alt": [
{
"language": "x-default",
"text": "To be returned unopened by 31 December 2026"
},
{
"language": "fr",
"text": "À rendre sans l’ouvrir, au plus tard le 31 décembre 2026"
},
{
"language": "de",
"text": "Ungeöffnet bis zum 31. Dezember 2026 zurückzugeben"
}
]
},
"description": "The conditions of the loan, in each language they were agreed in",
"value_type": "lang_alt"
}
]
}
]
},
"items": [
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 742.0,
"urx": 523.0,
"ury": 780.0
},
"content": "Records office cover sheet",
"font": "DejaVuSans",
"font_size": 20.0,
"space_after": 14.0,
"pages": [
1
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 651.0,
"urx": 523.0,
"ury": 742.0
},
"content": "The fields below are the records office's own. No part of the PDF standard knows what a retention date is, so the file explains itself: each field arrives in the metadata packet with its name, the way it is to be read, who it is written for, and what it means. An archival validator accepts them on that description, and refuses metadata that turns up without one.",
"font": "DejaVuSans",
"font_size": 10.5,
"leading": 15.0,
"align": "justify",
"space_after": 16.0,
"pages": [
1
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 608.6,
"urx": 523.0,
"ury": 651.0
},
"content": "What the sheet says",
"font": "DejaVuSans",
"font_size": 12.0,
"space_before": 20.0,
"space_after": 8.0,
"pages": [
1
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 523.6,
"urx": 523.0,
"ury": 608.6
},
"content": "Reference\tRO-2026-004318\nDepartment\tPlanning\nRetainUntil\t2056-12-31T23:59:59+01:00\nClassification\tPublic\nSheets\t1",
"font": "DejaVuSans",
"font_size": 11.0,
"leading": 17.0,
"tabs": {
"method": "ruler",
"ruler": [
150.0
]
},
"pages": [
1
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 481.2,
"urx": 523.0,
"ury": 523.6
},
"content": "What the packet declares of each of them",
"font": "DejaVuSans",
"font_size": 12.0,
"space_before": 20.0,
"space_after": 8.0,
"pages": [
1
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 383.2,
"urx": 523.0,
"ury": 481.2
},
"content": "rec:Reference\tText · external · The reference the records office files the dossier under\nrec:Department\tText · external · The department the dossier came from\nrec:RetainUntil\tDate · internal · The date the dossier may be destroyed, and not before\nrec:Classification\tText · external · How widely the dossier may be circulated\nrec:Sheets\tInteger · internal · How many sheets the dossier holds",
"font": "DejaVuSans",
"font_size": 9.5,
"leading": 14.0,
"hanging_list": {
"marker": 0.0,
"body": 150.0
},
"pages": [
1
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 326.2,
"urx": 523.0,
"ury": 383.2
},
"content": "Every value above is written twice: once on this page, and once in the packet a machine reads, under the prefix the schema names. Reading the file's metadata gives back this table, field for field.",
"font": "DejaVuSans",
"font_size": 9.0,
"leading": 13.0,
"space_before": 18.0,
"pages": [
1
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 742.0,
"urx": 523.0,
"ury": 780.0
},
"content": "What else a packet can carry",
"font": "DejaVuSans",
"font_size": 20.0,
"space_after": 14.0,
"pages": [
2
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 636.0,
"urx": 523.0,
"ury": 742.0
},
"content": "A second schema, the loan record's, carries fields of the six other kinds a property may be read as, and two lists: the witnesses to the loan, in no particular order, and each change of hands, in order, which is a structure the packet describes field by field. The conditions of the loan are one text in three languages, each version marked with its language. The document states its keywords, when it changed and whether it was trapped, and this page carries a packet of its own.",
"font": "DejaVuSans",
"font_size": 10.5,
"leading": 15.0,
"align": "justify",
"space_after": 16.0,
"pages": [
2
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 612.0,
"urx": 523.0,
"ury": 636.0
},
"content": "Declared in the namespace https://hqf-pdf.example/ns/loans/1.0/, under the prefix loan:",
"font": "DejaVuSans",
"font_size": 10.0,
"leading": 14.0,
"space_before": 10.0,
"pages": [
2
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 290.0,
"urx": 523.0,
"ury": 612.0
},
"content": "loan:Sealed\tTrue · Boolean · Whether the dossier left the office sealed\nloan:Format\tapplication/pdf · MIMEType · The media type the dossier is lent in\nloan:Custodian\tHQF Development · ProperName · Who holds the dossier while it is out\nloan:ShelfMetres\t1.5 · Real · How much shelf the dossier takes, in metres\nloan:Series\thttps://hqf-pdf.com/records/series/42 · URI · The series the dossier belongs to\nloan:Catalogue\thttps://hqf-pdf.com/records/catalogue · URL · Where the office's catalogue is read\nloan:Witnesses\tClaire Martin; Jan de Vries · bag ProperName · Who witnessed the loan\nloan:Movements\t2026-09-01, Claire Martin; 2026-09-17, HQF Development · seq Movement · Each time the dossier changed hands, in order\nloan:Conditions\tx-default: To be returned unopened by 31 December 2026; fr: À rendre sans l’ouvrir, au plus tard le 31 décembre 2026; de: Ungeöffnet bis zum 31. Dezember 2026 zurückzugeben · Lang Alt · The conditions of the loan, in each language they were agreed in\nMovement\tOne change of hands of a dossier\nmvt:When\tDate · The day the dossier changed hands\nmvt:Holder\tProperName · Who took the dossier",
"font": "DejaVuSans",
"font_size": 9.5,
"leading": 14.0,
"hanging_list": {
"marker": 0.0,
"body": 150.0
},
"pages": [
2
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 252.0,
"urx": 523.0,
"ury": 290.0
},
"content": "The document's keywords: archive, planning, retention; it changed on 2026-09-17T14:05:00+02:00; trapped: not known.",
"font": "DejaVuSans",
"font_size": 10.0,
"leading": 14.0,
"space_before": 10.0,
"pages": [
2
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 214.0,
"urx": 523.0,
"ury": 252.0
},
"content": "That date as PDF writes it: D:20260917140500+02'00'; read back: 2026-09-17T14:05:00+02:00.",
"font": "DejaVuSans",
"font_size": 10.0,
"leading": 14.0,
"space_before": 10.0,
"pages": [
2
]
},
{
"type": "flow",
"rect": {
"llx": 72.0,
"lly": 176.0,
"urx": 523.0,
"ury": 214.0
},
"content": "This page carries a packet of 2420 bytes of its own; the same facts claiming PDF/A-3b, PDF/UA-1 and PDF/X-4 would weigh 4885 bytes.",
"font": "DejaVuSans",
"font_size": 10.0,
"leading": 14.0,
"space_before": 10.0,
"pages": [
2
]
}
],
"page_metadata": [
{
"page": 2,
"metadata": {
"facts": {
"title": "What else a packet can carry"
}
}
}
]
}
|