There will be no courses. What was there: one draft called "jk" with two empty
lessons, and 4,000 lines of code around it — courses, modules, lessons,
enrolments, per-lesson progress, SCORM, BigBlueButton, completion certificates,
three React pages, a router, two models.
Its real cost was everywhere else. Every query that measured practice had to
remember `Quiz.course_id.is_(None)`, and forgetting it in one place would have
silently mixed course attempts into a learner's analytics; the bank predicate
carried a subquery to exclude a course's own questions from every search,
recommendation and share; quiz access had a second, parallel rule about
enrolment. All of that is gone, so the remaining rules say what they mean.
`quizzes.allow_review` goes with it. It was only ever enforced for a course
quiz, so it had become a promise nothing keeps — the public session page was
still offering "no answer review" about sessions that review fine.
The fixtures' question 5 lived in a course quiz and stood for "a question that
exists but is not in your bank". There is no such thing now — a question is in
the bank unless it is deleted — so the counts it kept out of the numbers are
back in, and the tests that turned on it now turn on deletion or on the
attempt that actually holds a question.
Files the LMS uploaded stay on disk and stay protected: LEGACY_LMS_PREFIXES in
app/utils/upload_access.py is what keeps them unreachable.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TqXevQJhxFrM7jJg82cgZN
The document matcher decided by extension and fell through to "decode whatever
this is as UTF-8" for everything that was not a .pdf. A shell script, an HTML
page, a CSV or a JPEG all became a search query, and a file called report.pdf
holding something else was read as a PDF.
Three questions now, in order, before anything else touches the file: is it
under 2 MB (read one byte past the cap, so a huge file is never held in memory
to be measured); what is it, sniffed from the leading bytes; and what text is
in it. PDF, DOCX and images, and nothing else — 415 with a sentence naming what
to upload instead. DOCX is parsed from the zip with no new dependency and is
checked against the one attack that shape allows, a member that unpacks to far
more than the file's size suggests. An image is read by the tool model, and
where no tool model is configured it says so rather than 500ing.
On injection, since that is the question people mean: there is no path from an
uploaded file to code that runs. The extracted text is a search query — bound
parameter to Postgres, never concatenated into SQL — and the content of a
message to a model. It is never rendered as HTML, never written to disk, never
passed to a shell. Control characters are stripped because they make queries
that match nothing, not because anything would interpret them.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TqXevQJhxFrM7jJg82cgZN
`Question.is_shared` defaulted to 1 and was only ever set by a route nothing
called, so in practice it divided the bank into "everything" and "everything,
plus your own private ones" — a distinction that cost every recommendation
denominator a join and never changed an answer. Who may reach the bank is the
site's own access rules; who may manage a question is the category grant tree.
So the two predicates the whole bank was built on are now the same thing, and
say what they actually mean: a question is out of reach if it has been deleted
or belongs to a course. Nothing else. The column is dropped, the route that set
it is gone, the bulk "share" action with it, and the Private tile and pill go
from the question manager.
The tests that turned on it have been rewritten rather than deleted, because
the rule they were really about survives: revoking a question still revokes
every session carrying it — by deleting it, which is the only revocation left.
Several others named a category holding exactly two reachable questions and
then answered two particular ids; that category holds four now, so they name
the pair instead. A session's own sharing flag is untouched — that is a
different thing, and it is still how a session is handed to somebody.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TqXevQJhxFrM7jJg82cgZN
Exams (migration v4b5c6d7e8f9)
"Pediatrics Boards" was a hardcoded checkbox that filtered nothing. Exams are now
rows: Pediatrics Boards and USMLE Step 2 CK ship seeded, and everything already
in the bank is linked to the boards. Membership is a link table, not a column,
because one paediatric cardiology question can count towards several exams.
The learner's choice lives on `users.active_exam_id`, so it follows them between
devices instead of sitting in one browser's storage. Choosing an exam scopes the
bank; a question with no exam links stays visible, since unlinked content is
unclassified rather than excluded. A switcher sits in the navbar.
AI mode — matching, never generating
Both entry points build a test from the educator-reviewed questions that already
exist, ranked against the request. Nothing is invented:
- POST /questions/builder/describe turns "what I want to study" into a test.
- POST /questions/builder/from-upload matches a document against the bank. The
file is read in memory and never stored — it is a search query, not a source
of questions, so there is nothing to retain or expire. 10 MB cap, 30 questions.
Handing a whole document to `websearch_to_tsquery` builds one enormous
conjunction that matches nothing, so text over 300 characters is reduced to its
most distinctive terms, OR-joined, before it reaches the lexical ranker.
Continue your study (migration w5c6d7e8f9a0)
A dashboard panel with the sessions in flight and the articles most recently
opened. `article_views` records one row per learner and article, written best
effort so a reading page never fails because a bookkeeping write did.
Tests: 5 new exam tests (active exams and counts, choice persisted and cleared,
unknown/inactive refused, bank scoping including unlinked questions, moderator-only
creation) and 7 for AI-mode matching (no questions created, invisible questions
excluded, no-match reported rather than an empty test, upload limits enforced).
Full suites green: 113 backend, 136 frontend, build clean.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PpfzbZ1QTLMeVYxM2kyq8m
