Delete the byte-oriented KVStore/VersionedStore abstraction and the
DynamoDB/memory KV backends. Add a generic typed store (DocStore[T] with
Provider/Collection/Typed) persisting each value as a flattened native
Mongo document (storedDoc[T] via bson inline) — no value envelope.
- MongoDB is the only runtime backend; memory kept for tests/local.
- All modules + deploynotify use typed stores; persisted structs carry
bson tags == json names (incl. nested lolschedule/wordle types).
- lolschedule wraps its array/scalar values in named structs.
- migrate-dynamo-to-mongo writes the flattened shape via Typed[bson.M]
with wrap rules; Scan/--dry-run/--verify retained.
Verified: go vet/build clean; full go test green hermetically and
in-container vs real Mongo 7 + DynamoDB Local (storage integration +
migrator e2e).
Replace content-addressed storage versioning (CAS) with explicit version fields
on documents. Versions are managed via optimistic locking pattern: Get returns
version, Put increments atomically and fails if version mismatch detected.
Callers (portfolio, lolschedule) updated to use GetVersioned/PutVersioned,
simplifying concurrency handling and eliminating CAS overhead.
Parallelizing the per-symbol fetches opened N simultaneous TLS handshakes into
an empty connection pool. On the memory-constrained Lambda (256MB ~0.15 vCPU)
those CPU-bound handshakes thrashed and each exceeded the per-fetch timeout, so
every ticker rendered "(no price)". Sequential fetches reuse the price client's
keep-alive connection (one handshake), which is why the code was sequential by
design.
- revert stock and coin stats loops to sequential (keep the reply-budget
sub-context and 3s per-fetch timeout)
- log per-symbol fetch failures instead of silently swallowing them
Stats handlers reused the single bounded update context for both upstream
price fetches and the final Telegram reply, while per-upstream HTTP timeouts
equalled the whole-handler budget. One slow upstream drained the deadline and
the reply failed with "context deadline exceeded" (observed on /stock_stats).
- add chathelper.FetchContext: fetches run under a child context that reserves
a tail of the deadline for the reply, which is sent on the original context
- cap kbs/coin/gold/vnappmob HTTP timeouts at 3s so one hung upstream cannot
consume the reply budget
- fetch held stock/coin prices concurrently (bounded) so total latency tracks
the slowest single fetch instead of their sum; per-symbol failures degrade to
a "no price" line and the summary still sends
- Change /coin_sell semantics from quantity to USD amount
- Add price-validity and dust-quantity guards to buy/sell
- Improve usage text and error messages
- Add tests for invalid amount, dust, zero price, and insufficient holdings
tiennm99