Generic in-process scheduler for the expensive PDF-extraction child process.
A pool runs at most `slots` jobs, keeps at most `queue` waiting, and refuses a
waiter past `wait`. Do() applies six rules in order: join an existing running
or queued job (no slot, allowed while the caller holds another, fn may be nil);
refuse a caller that already has a job in flight; take a free slot, else queue
(first-come-first-served, else ErrBusy); run fn under context.WithoutCancel so
the flight outlives a caller that leaves; broadcast the result to every sharer
with no caching and a recovered panic returned as an error. Running counts only
jobs holding a slot; Queued counts the line; Waiting(key) counts joiners.
Co-Authored-By: ornith-1.5-35b-a3b <ornith-1.5-35b-a3b@llama.cpp.invalid>
Add pdf_doc/pdf_page tables plus PDFEntry, PDFKey, PutPDF (one transaction,
old pages deleted first), GetPDF (page-ordered, updates last_hit) and TouchPDF
(304 revalidation moves only fetched_at). PDF documents count toward Size() and
are evicted whole by oldest use; PDFH/PDFM counters added. evict() now breaks
last_hit ties by rowid so same-second inserts evict in insertion order.
Co-Authored-By: ornith-1.5-35b-a3b <ornith-1.5-35b-a3b@llama.cpp.invalid>
The parser is pure Go but a goroutine cannot be killed, so extraction runs in
a child process: the binary re-executed as `sift pdftext`, reading the PDF on
stdin and writing JSON Lines on stdout, killed at a deadline by the parent.
pdftext.go holds the types, the five errors, Extract (reader.Open with
ErrWrongPassword -> ErrEncrypted, per-page recover, trailer /Info /Title, and
rule-3 UTF-16BE/Latin-1 text decode) and ChildMain (soft 768 MiB memory limit,
-no env read, no network, exit codes 0/3/4/1). outline.go walks /Outlines ->
/First -> /Next with /First children at level+1, resolving /Dest and /GoTo /A
dests to 1-based pages, bounded at 10,000 items and never visiting an object
twice. runner.go is the Runner: env-isolated child (nil env is an empty
environment), 60 s deadline, 64 MiB output cap, 200 MiB stdin cap, stderr
capped at 4 KiB, exit-code to error mapping, and Doc parsing with ErrNoText.
cmd/sift/main.go adds the unlisted `pdftext` case. tools.go is removed; the
go-pdfkit modules stay vendored.
Co-Authored-By: ornith-1.5-35b-a3b <ornith-1.5-35b-a3b@llama.cpp.invalid>
Recognise PDFs in clean.Kind (declared types and %PDF- sniffing on
octet-stream/bodyless bodies), give PDF responses the 100 MB body cap and
120 s deadline while web pages keep 5 MB / 20 s, and add FetchIf, which
sends If-None-Match / If-Modified-Since and maps a 304 to a Resource with
Status 304 and an empty Body. Fetch and FetchIf share one doFetch path for
guard, client, limits and error mapping.
Co-Authored-By: ornith-1.5-35b-a3b <ornith-1.5-35b-a3b@llama.cpp.invalid>
docs/plans/p5a: 01 kind+fetch limits, 02 pdftext child + runner, 03 dcache PDF tables,
04 pdfpool, 05 pdfdoc render (map/pages/grep), 06 api, 07 digest citations, metrics, CLI,
skill, unit, README. Given tests compile against a panic-only skeleton and fail there for the
intended reasons; PDFs for tests are built by internal/pdftest (given), plus two qpdf-encrypted
fixtures.
Owner changes for the run: vendor go-pdfkit/extract v0.3.0 + reader v0.6.0 (pinned via
tools.go until task 02); AGENTS.md, tools/run-plan.sh (enforces a Co-Authored-By trailer for
the model), docs/implementer-log.md, `make gate`; gofmt (whitespace) on clean.go and guard;
TestUnsupportedType uses a zip now that PDFs are supported; requestDeadline 90→210 s and
writeTimeout 120→240 s for the PDF path's worst case.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
kyleandornith-1.5-35b-a3b
