The first iteration of this layer landed scaffolding plus shallow
seed-URL ingest, which produced 300-1000 byte stubs (front matter
+ nav chrome only) instead of real book content. Fox flagged
that as the wrong outcome — we were supposed to track down the
actual texts.
This commit fixes it by adding the deep-ingest path: each
manifest entry now carries `crawl_url` + `crawl_depth` +
`crawl_max` fields, and `make crawl-textbooks` iterates them
through the existing BFS crawler (one shard per host).
Manifest changes
================
Three URL fixups uncovered by the first crawl attempt:
- PreTeXt textbooks (Bogart, Keller-Trotter, Levin) ship an
`index.html` that's a 1-line meta-refresh redirect; the BFS
crawler doesn't follow meta-refresh, so the seed URL has to
point at the actual content entry (`frontmatter.html`,
`app-comb-2.html`, `ctgd/index.html`).
- Open Data Structures uses trailing-slash directory paths
(`/ods-cpp/`, `/ods-python/`, `/ods-java/`), not `/ods-cpp.html`.
- `appliedcombinatorics.org` declares `Crawl-Delay: 20` in
robots.txt — full BFS takes ~25 minutes; documented in the
manifest entry's notes so operators know to background it.
Hilbert + Boole stay flagged as `urls: []` placeholders because
PG eBooks #17384 + #15114 ship as PDF/TeX only (no HTML format).
Their `tex_url` + `pdf_url` fields are now preserved on the
entry for the future PDF/TeX source ticket.
Make targets
============
- crawl-textbooks — BFS-crawl every entry with `crawl_url`
- crawl-textbooks-stats — docs/chunks/size summary across crawl shards
Helper script: `bench/scripts/textbooks_manifest.py crawl-targets`
emits one tab-separated `<url>\t<depth>\t<max>\t<id>` row per
entry that declares a `crawl_url`.
Real-content verification
=========================
Crawl results across 4 of 5 textbooks (Keller-Trotter still
running in background due to crawl-delay; expected to complete
in ~25 min):
crawl_bogart_openmathbooks_org.db docs=44 chunks=161 971 KB
crawl_discrete_openmathbooks_org.db docs=51 chunks=376 1929 KB
crawl_en_wikisource_org.db docs=30 chunks=110 1651 KB
crawl_opendatastructures_org.db docs=64 chunks= 84 1110 KB
TOTAL 189 docs, 731 chunks
FTS5 spot-checks confirm substantive content landed:
- Bogart "binomial coefficient" → "CTGD Partitions and Stirling
Numbers" chapter, top hit
- Levin "modus ponens" → "Propositional Logic" chapter, top hit
That's the real lift signal we were after. Out-of-scope
follow-ups remain: PDF/TeX support for PG editions (Hilbert,
Boole) and full Aristotle Owen-translation depth (currently
~75% complete on Wikisource).