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

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_TRUST_WIRE	unset	Opt-in promise that the endpoint is a real PLC or RSEmulate 500 golden-box (not ab_server). Required for integration tests to actually run; without it the tests skip with an upstream-gap message even when TCP reaches a listener. See the Known limitations section below.

Run the integration tests

In a separate shell with a container up:

cd C:\Users\dohertj2\Desktop\lmxopcua
dotnet test tests\ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.IntegrationTests

Against the Docker ab_server the suite skips with a pointer to the upstream gap (see Known limitations). Against real SLC / MicroLogix / PLC-5 hardware or a RSEmulate 500 box:

$env:AB_LEGACY_ENDPOINT = "10.0.1.50:44818"
$env:AB_LEGACY_TRUST_WIRE = "1"
dotnet test tests\ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.IntegrationTests

AbLegacyServerFixture TCP-probes the endpoint at collection init and sets a skip reason that captures both cases: unreachable endpoint and reachable-but-wire-untrusted. 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 PCCC dispatcher (confirmed upstream gap, verified 2026-04-21)

ab_server accepts TCP at :44818 but its PCCC dispatcher is not functional. Running with --plc=SLC500 --debug=5 shows no request logs when libplctag issues a read, and every read surfaces as BadCommunicationError (libplctag status 0x80050000). This matches the libplctag docs' description of PCCC support as less-mature than CIP in the bundled ab_server tool.

Fixture behavior. To avoid a loud row of failing tests on the integration host every time someone docker compose ups the SLC500 profile, AbLegacyServerFixture gates on a second env var AB_LEGACY_TRUST_WIRE. The matrix:

Endpoint reachable?	AB_LEGACY_TRUST_WIRE set?	Result
No	—	Skip ("not reachable")
Yes	No	Skip ("ab_server PCCC gap")
Yes	1 or true	Run

The test bodies themselves are correct for real hardware — point AB_LEGACY_ENDPOINT at a real SLC 5/05 / MicroLogix 1100/1400 / PLC-5, set AB_LEGACY_TRUST_WIRE=1, and the smoke tests round-trip cleanly.

Resolution paths (pick one):

1. File an ab_server bug in libplctag/libplctag to expand PCCC server-side coverage.
2. Golden-box tier via Rockwell RSEmulate 500 — closer to real firmware, but license-gated + RSLinx-dependent. Set AB_LEGACY_TRUST_WIRE=1 when the endpoint points at an Emulate box.
3. Lab rig — used SLC 5/05 / MicroLogix 1100 on a dedicated network (task #222); the authoritative path.

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