Files touched — docs/drivers/Modbus-Test-Fixture.md dropped the key-files pointer at deleted Pymodbus/ + flipped "primary launcher is Docker, native fallback retained" framing to "Docker is the only supported launch path" (matching the code). docs/v2/dev-environment.md dropped the "skips both Docker + native-binary paths" parenthetical from AB_SERVER_ENDPOINT + flipped the "Native fallbacks" subsection to a one-liner that says Docker is the only supported path. docs/v2/modbus-test-plan.md rewrote §Harness from "pip install pymodbus + serve.ps1" setup pattern to "docker compose --profile <…> up" + updated the §PR 43 status bullet to point at Docker/profiles/. docs/v2/test-data-sources.md §"CI fixture (task #180)" rewrote the AB CIP section from "LocateBinary() picks binary off PATH" + GitHub Actions zip-download step to "Docker is the only supported reproducible build path" + docker compose GitHub Actions step; dropped the pinned-version SHA256 table + lock-file reference because the Dockerfile's LIBPLCTAG_TAG build-arg is the new pin. Code docstrings + error messages — these are developer-facing operational text too. ModbusSimulatorFixture SkipReason strings (both branches) now point at `docker compose -f Docker/docker-compose.yml --profile standard up -d` instead of the deleted `Pymodbus\serve.ps1`; doc-comment at the top references Docker/docker-compose.yml. Snap7ServerFixture SkipReason strings + doc-comment point at Docker/docker-compose.yml instead of PythonSnap7/serve.ps1. S7_1500Profile.cs docstring updated. Modbus Dockerfile comment pointing at deleted tests/.../Pymodbus/README.md redirected to docs/drivers/Modbus-Test-Fixture.md. DL205Profile.cs + DL205StringQuirkTests.cs + S7_1500Profile.cs (in Modbus project) docstrings flipped from Pymodbus/*.json references to Docker/profiles/*.json. Left untouched deliberately: docs/v2/implementation/exit-gate-phase-2-closed.md — that's a historical as-of-2026-04-18 snapshot documenting what was skipped at Phase 2 closure; rewriting would lose the date-stamped context. Its "oitc/modbus-server Docker container not started" + "ab_server binary not on PATH" lines describe the fixture landscape that existed at close time, not current operational guidance. Final sweep confirms zero remaining `Pymodbus/` / `PythonSnap7/` / `LocateBinary` / `AbServerSeedTag` / `BuildCliArgs` / `AbServerPlcArg` mentions anywhere in tracked files outside that historical exit-gate doc. Whole-solution build still 0 errors. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Modbus integration-test fixture — pymodbus simulator
The Modbus driver's integration tests talk to a
pymodbus simulator running as a
pinned Docker container. One image, per-profile service in compose, same
port binding (5020) regardless of which profile is live. Docker is the
only supported launch path — a fresh clone needs Docker Desktop and
nothing else.
| File | Purpose |
|---|---|
Dockerfile |
python:3.12-slim-bookworm + pymodbus[simulator]==3.13.0 + the four profile JSONs |
docker-compose.yml |
One service per profile (standard / dl205 / mitsubishi / s7_1500); all bind :5020 so only one runs at a time |
profiles/*.json |
Same seed-register definitions the native launcher uses — canonical source |
Run
From the repo root:
# Build + start the standard profile
docker compose -f tests\ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests\Docker\docker-compose.yml --profile standard up
# DL205 quirks
docker compose -f tests\ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests\Docker\docker-compose.yml --profile dl205 up
# Mitsubishi MELSEC quirks
docker compose -f tests\ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests\Docker\docker-compose.yml --profile mitsubishi up
# Siemens S7-1500 MB_SERVER quirks
docker compose -f tests\ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests\Docker\docker-compose.yml --profile s7_1500 up
Detached + stop:
docker compose -f tests\...\Docker\docker-compose.yml --profile dl205 up -d
docker compose -f tests\...\Docker\docker-compose.yml --profile dl205 down
Only one profile binds :5020 at a time; switch by stopping the current
service + starting another. The integration tests discriminate by a
separate MODBUS_SIM_PROFILE env var so they skip correctly when the
wrong profile is live.
Endpoint
- Default:
localhost:5020 - Override with
MODBUS_SIM_ENDPOINT(e.g. a real PLC on:502).
Run the integration tests
In a separate shell with one profile live:
cd C:\Users\dohertj2\Desktop\lmxopcua
dotnet test tests\ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests
ModbusSimulatorFixture probes localhost:5020 at collection init +
records a SkipReason when unreachable, so tests stay green on a fresh
clone without Docker running.
References
docs/drivers/Modbus-Test-Fixture.md— coverage map + gap inventorydocs/v2/dev-environment.md§Docker fixtures — full fixture inventory