Ryan Malloy
f202dbce0c
Project goal: pure-Python implementation of the Informix SQLI wire protocol. No CSDK, no JVM, no native deps. Targets icr.io/informix /informix-developer-database (port 9088) as the dev/test instance. Phase 0 is a documentation-only spike that gates all implementation work. The four scaffolds: - README.md: project status and Phase 0 deliverable index - docs/PROTOCOL_NOTES.md: byte-level wire-format reference (TBD) - docs/JDBC_NOTES.md: reverse-lookup index into the decompiled IBM JDBC driver (4.50.4.1), populated from build/jdbc-src/ once the decompile lands - docs/DECISION_LOG.md: running rationale, with the Phase-1 paramstyle /Python-floor/autocommit decisions pre-locked so they don't churn later CLAUDE.md is gitignored — operator-private context, public-PyPI repo.
3.0 KiB
IBM JDBC Driver — Wire Protocol Class Index
Phase 0 spike artifact. Reverse-lookup index into the decompiled
com.ibm.informix:jdbc:4.50.4.1JAR. This document tells us which Java class to read when we want to understand how the JDBC driver implements a given wire-protocol concern.Legal note: the decompiled source lives in
build/jdbc-src/and is not committed to this repository. It is consulted as a clean-room understanding reference only. The Python implementation insrc/informix_db/is written fromPROTOCOL_NOTES.md(which cites observed packet bytes), not from the Java source.
Decompilation
# Get the JAR
curl -O https://repo1.maven.org/maven2/com/ibm/informix/jdbc/4.50.4.1/jdbc-4.50.4.1.jar
# Decompile (CFR — https://www.benf.org/other/cfr/)
java -jar cfr.jar jdbc-4.50.4.1.jar --outputdir build/jdbc-src/
Driver version: 4.50.4.1 (latest as of 2026-05-02 on Maven Central).
Top-level package layout
TBD — populate after decompilation.
Expected (from research):
com.informix.jdbc— driver entry, connection, statement, result-set- Likely subpackages for protocol I/O, type system, error mapping
Class index (responsibility → class)
| Concern | Class | File path under build/jdbc-src/ |
Notes |
|---|---|---|---|
| Driver entry point | com.informix.jdbc.IfxDriver |
TBD | implements java.sql.Driver |
| Connection | com.informix.jdbc.IfxConnection |
TBD | extends java.sql.Connection |
| Wire socket I/O | TBD | TBD | look for DataOutputStream / DataInputStream users |
| Message framing | TBD | TBD | length-prefix + type-tag handlers |
| Login handshake | TBD | TBD | username/password/database selection |
| Auth method dispatch | TBD | TBD | plain / obfuscated / GSSAPI |
| Statement execute | TBD | TBD | EXECUTE / EXECUTE IMMEDIATE entry points |
| Prepared statement | TBD | TBD | parameter descriptors |
| Result-set parsing | TBD | TBD | column descriptors + row decoding |
| Type codecs (encoders) | TBD | TBD | IfxTypeId likely; per-type encoder methods |
| Type codecs (decoders) | TBD | TBD | per-type decoder methods |
| Error decoding (SQLSTATE) | TBD | TBD | error-message → SQLException mapping |
| Disconnection | TBD | TBD | logout / socket close |
| Protocol trace | com.informix.jdbc.*.getProtoTrace |
TBD | Useful debug hook; understand what it logs |
Method-level pointers
As we identify specific methods that map to specific wire bytes, record them here. Format:
Class#method() → wire effect.
- (none yet)
Things to grep for
# Wire I/O entry points
grep -rln "DataOutputStream\|DataInputStream" build/jdbc-src/
# Type code constants
grep -rln "TYPEID\|IfxTypeId\|TypeId" build/jdbc-src/
# Auth method strings
grep -rln "OBFUSCATE\|PWDOBFUSCATION\|GSS\|KERBEROS" build/jdbc-src/
# SQLSTATE / error mapping
grep -rln "SQLSTATE\|SQLException" build/jdbc-src/