Ryan Malloy
389c32434c
SELECT on BLOB or CLOB columns no longer requires raw byte interpretation. The 72-byte server-side locator is wrapped in a typed BlobLocator or ClobLocator (frozen dataclass) so the column is recognizable as "server-side reference, not actual bytes". Wire-protocol findings: * Smart-LOB columns DON'T appear with their nominal type codes (102/101) in SQ_DESCRIBE. They surface as UDTFIXED (41) with extended_id 10 (BLOB) or 11 (CLOB) and encoded_length=72 (locator size). * Retrieving the actual bytes requires SQ_FPROUTINE (103) RPC to invoke ifx_lo_open, plus SQ_LODATA (97) for chunked transfer, plus another SQ_FPROUTINE for ifx_lo_close. That's a Phase 10 lift — roughly 2x the protocol surface of Phase 8. Server config needed (added to Phase 7 setup): * sbspace: onspaces -c -S sbspace1 ... * default sbspace: onmode -wm SBSPACENAME=sbspace1 What ships in Phase 9: * informix_db.BlobLocator(raw: bytes) — 72-byte frozen wrapper * informix_db.ClobLocator(raw: bytes) — distinct type, same shape * Row decoder branch in _resultset.parse_tuple_payload * Wire constants SQ_LODATA=97, SQ_FPROUTINE=103, SQ_FPARAM=104 Tests: * 11 unit tests in test_blob_locator_unit.py (no Informix needed) — construction, immutability, equality, hash, repr safety, size validation. * 4 integration tests in test_smart_lob.py — fixture seeds via JDBC reference client (smart-LOB writes also need deferred protocols). * RefBlob.java helper in tests/reference/ for seeding via JDBC. Total: 64 unit + 111 integration = 175 tests. Locator design note: __repr__ omits the raw bytes (they're opaque to the client). Same-bytes locators of different families compare unequal — BlobLocator(x) != ClobLocator(x) — to avoid silent type confusion.
informix-db
Pure-Python driver for IBM Informix IDS, speaking the SQLI wire protocol over raw sockets. No IBM Client SDK. No JVM. No native libraries.
Status
🟢 Phase 1 complete. connect() / close() work end-to-end against a real Informix server. Cursor / execute / fetch land in Phase 2.
To our knowledge this is the first pure-socket Informix driver in any language — every other Informix driver (IfxPy, the legacy informixdb, ODBC bridges, Perl DBD::Informix) wraps either IBM's CSDK or the JDBC JAR.
Quick start
import informix_db
with informix_db.connect(
host="127.0.0.1", port=9088,
user="informix", password="in4mix",
database="sysmaster", server="informix",
) as conn:
# cursor() / execute() / fetchone() arrive in Phase 2
pass
Test against the official Informix dev container
docker compose -f tests/docker-compose.yml up -d # IBM Developer Edition, pinned by digest
uv sync --extra dev
uv run pytest # 34 unit tests (no Docker needed)
uv run pytest -m integration # 6 integration tests (needs the container)
Phase 0 artifacts (still useful — they ARE the public reference)
docs/PROTOCOL_NOTES.md— byte-level wire-format reference, derived from packet captures + JDBC decompilation, validated against a real serverdocs/JDBC_NOTES.md— index into the decompiled IBM JDBC driver's wire-protocol classesdocs/DECISION_LOG.md— running rationale for protocol / auth / type decisionsdocs/CAPTURES/— socat hex-dump captures of three reference scenarios (connect, SELECT, full DML cycle)tests/reference/RefClient.java— re-runnable JDBC ground-truth client for capturing fresh traces
License
MIT.