lmxopcua/tests/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.IntegrationTests/Docker/README.md

AB Legacy PCCC integration-test fixture — ab_server (Docker)

libplctag's ab_server supports both CIP (ControlLogix / CompactLogix / Micro800) and PCCC (SLC 500 / MicroLogix / PLC-5) families from one binary. This fixture reuses the AB CIP Docker image (otopcua-ab-server:libplctag-release) with different --plc flags. No new Dockerfile needed — the compose file's build: block points at the AB CIP Docker/ folder so docker compose build from here reuses the same multi-stage build.

Docker is the only supported launch path; a fresh clone needs Docker Desktop and nothing else.

File	Purpose
docker-compose.yml	Three per-family services (slc500 / micrologix / plc5); all bind :44818

Run

From the repo root:

# SLC 500 family — widest PCCC coverage
docker compose -f tests\ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.IntegrationTests\Docker\docker-compose.yml --profile slc500 up

# Per-family
docker compose -f tests\...\Docker\docker-compose.yml --profile micrologix up
docker compose -f tests\...\Docker\docker-compose.yml --profile plc5 up

Detached + stop:

docker compose -f tests\...\Docker\docker-compose.yml --profile slc500 up -d
docker compose -f tests\...\Docker\docker-compose.yml --profile slc500 down

First run builds the otopcua-ab-server:libplctag-release image (~3-5 min — clones libplctag + compiles ab_server). If the AB CIP fixture already built the image locally, docker reuses the cached layers + this runs in seconds. Only one family binds :44818 at a time; to switch families stop the current service + start another.

Endpoint

• Default: localhost:44818 (EtherNet/IP standard)
• Override with AB_LEGACY_ENDPOINT=host:port to point at a real SLC / MicroLogix / PLC-5 PLC on its native port.

Env vars

Var	Default	Purpose
AB_LEGACY_ENDPOINT	localhost:44818	host:port of the PCCC endpoint.
AB_LEGACY_CIP_PATH	1,0	CIP routing path portion of the ab://host:port/<path> URI. ab_server rejects empty paths at the CIP unconnected-send layer; real SLC/MicroLogix/PLC-5 hardware accepts empty (no backplane). Set to empty (AB_LEGACY_CIP_PATH=) when pointing at real hardware.
AB_LEGACY_COMPOSE_PROFILE	unset	When set (e.g. slc500), the parametric theory filters to that profile. Only one compose container binds :44818 at a time; set this to the profile currently up so the suite doesn't try to hit e.g. the Slc500 family against the PLC-5 container. Leave unset for real-hardware runs (all 3 families parameterize).

Run the integration tests

In a separate shell with a container up, tell the suite which profile is running so only the matching theory-parameterization executes:

cd C:\Users\dohertj2\Desktop\lmxopcua
$env:AB_LEGACY_COMPOSE_PROFILE = "slc500"   # or "micrologix" / "plc5"
dotnet test tests\ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.IntegrationTests

Against real SLC / MicroLogix / PLC-5 hardware, set the endpoint + an empty cip-path + leave the profile unset so all 3 parameterizations run (real PLCs answer any valid family):

$env:AB_LEGACY_ENDPOINT = "10.0.1.50:44818"
$env:AB_LEGACY_CIP_PATH = ""     # empty — real hardware has no backplane
dotnet test tests\ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.IntegrationTests

AbLegacyServerFixture TCP-probes the endpoint at collection init and sets a skip reason when the listener isn't reachable. Tests use [AbLegacyFact] / [AbLegacyTheory] which check the same gate.

What each family seeds

PCCC tag format is <file>[<size>] without a type suffix — file letter implies type:

• N = 16-bit signed integer
• F = 32-bit IEEE 754 float
• B = 1-bit boolean (stored as uint16, bit-addressable via /n)
• L = 32-bit signed integer (SLC 5/05 V15+ only)
• ST = 82-byte ASCII string (MicroLogix-specific extension)

Family	Seeded tags	Notes
SLC 500	N7[10], F8[10], B3[10], L19[10]	Baseline; covers the four numeric file types a typical SLC project uses
MicroLogix	B3[10], N7[10], L19[10]	No F8 — MicroLogix 1000 has no float file; use L19 when scaled integers aren't enough
PLC-5	N7[10], F8[10], B3[10]	No L — PLC-5 predates the L file type; DINT equivalents went in integer files

Known limitations

ab_server rejects empty CIP paths

libplctag's ab_server enforces a non-empty CIP routing path at the unconnected-send layer before forwarding to the PCCC dispatcher; a client-side ab://host:port/ with nothing after the / surfaces as BadCommunicationError (0x80050000) with no server-side log line.

Real SLC/PLC-5 hardware has no backplane routing, so an empty path is how field devices are addressed. The fixture defaults to /1,0 (port-1/slot-0 — the conventional ControlLogix backplane path) which the ab_server accepts; operators targeting real hardware set AB_LEGACY_CIP_PATH= (empty) to exercise authentic wire semantics.

Previous versions of this README described PCCC as "upstream-broken" — the root cause turned out to be the cip-path gate above, not a gap in pccc.c. N-file (Int16), F-file (Float32), and L-file (Int32) round- trip cleanly across SLC500, MicroLogix, and PLC-5 modes.

Bit-file writes on ab_server

B3:0/5-style bit-in-boolean writes currently surface 0x803D0000 against ab_server --plc=SLC500; bit reads work. Non-blocking for the smoke suite (which targets N-file Int16 + F-file float reads), but bit-write fidelity isn't simulator-verified — route operator-critical bit writes to real hardware or RSEmulate 500 until upstream resolves.

Other known gaps (unchanged from ab_server)

• Timer / Counter file decomposition — PCCC T4 / C5 files contain three-field structs (.ACC / .PRE / .DN). Not in ab_server's scope; tests targeting T4:0.ACC stay unit-only.
• ST (ASCII string) files — real MicroLogix ST files have a length field plus CRLF-sensitive semantics that don't round-trip cleanly.
• Indirect addressing (N7:[N10:5]) — not in ab_server's scope.
• DF1 serial wire behaviour — the whole ab_server path is TCP; DF1 radio / serial fidelity needs real hardware.

See docs/drivers/AbLegacy-Test-Fixture.md for the full coverage map.

References

• libplctag on GitHub — ab_server lives under src/tools/ab_server/
• docs/drivers/AbLegacy-Test-Fixture.md — coverage map + gap inventory
• docs/v2/dev-environment.md §Docker fixtures — full fixture inventory
• ../../ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests/Docker/ — the shared Dockerfile this compose file's build: block references