docker compose up. Modbus — new tests/ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + pymodbus[simulator]==3.13.0) + docker-compose.yml with four compose profiles (standard / dl205 / mitsubishi / s7_1500) backed by the existing profile JSONs copied under Docker/profiles/ as canonical; native fallback in Pymodbus/ retained with the same JSON set (symlink-equivalent — manual re-sync when profiles change, noted in both READMEs). Port 5020 unchanged so MODBUS_SIM_ENDPOINT + ModbusSimulatorFixture work without code change. Dropped the --no_http CLI arg the old serve.ps1 + compose draft passed — pymodbus 3.13 doesn't recognize it; the simulator's http ui just binds inside the container where nothing maps it out and costs nothing. S7 — new tests/ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + python-snap7>=2.0) + docker-compose.yml with one s7_1500 compose profile; copies the existing server.py shim + s7_1500.json seed profile; runs python -u server.py ... --port 1102. Native fallback in PythonSnap7/ retained. Port 1102 unchanged. AB CIP — hardest because ab_server is a source-only C tool in libplctag's src/tools/ab_server/. New tests/ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests/Docker/ Dockerfile is multi-stage: build stage (debian:bookworm-slim + build-essential + cmake) clones libplctag at a pinned tag + cmake --build build --target ab_server; runtime stage (debian:bookworm-slim) copies just the binary from /src/build/bin_dist/ab_server. docker-compose.yml ships four compose profiles (controllogix / compactlogix / micro800 / guardlogix) with per-family ab_server CLI args matching AbServerProfile.cs. AbServerFixture updated: tries TCP probe on 127.0.0.1:44818 first (Docker path) + spawns the native binary only as fallback when no listener is there. AB_SERVER_ENDPOINT env var supported for pointing at a real PLC. AbServerFact/Theory attributes updated to IsServerAvailable() which accepts any of: live listener on 44818, AB_SERVER_ENDPOINT set, or binary on PATH. Required two CLI-compat fixes to ab_server's argument expectations that the existing native profile never caught because it was never actually run at CI: --plc is case-sensitive (ControlLogix not controllogix), CIP tags need [size] bracket notation (DINT[1] not bare DINT), ControlLogix also requires --path=1,0. Compose files carry the corrected flags; the existing native-path AbServerProfile.cs was never invoked in practice so we don't rewrite it here. Micro800 now uses the --plc=Micro800 mode rather than falling back to ControlLogix emulation — ab_server does have the dedicated mode, the old Notes saying otherwise were wrong. Updated docs: three fixture coverage docs (Modbus-Test-Fixture.md, S7-Test-Fixture.md, AbServer-Test-Fixture.md) flip their "What the fixture is" section from native-only to Docker-primary-with-native-fallback; dev-environment.md §Resource Inventory replaces the old ambiguous "Docker Desktop + ab_server native" mix with four per-driver rows (each listing the image, compose file, compose profiles, port, credentials) + a new Docker fixtures — quick reference subsection giving the one-line docker compose -f <…> --profile <…> up for each driver + the env-var override names + the native fallback install recipes. drivers/README.md coverage map table updated — Modbus/AB CIP/S7 entries now read "Dockerized …" consistent with OpcUaClient's line. Verified end-to-end against live containers: Modbus DL205 smoke 1/1, S7 3/3, AB CIP ControlLogix 4/4 (all family theory rows). Container lifecycle clean (up/test/down, no leaked state). Every fixture keeps its skip-when-absent probe + env-var endpoint override so dotnet test on a fresh clone without Docker running still gets a green run.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
docker compose up. Modbus — new tests/ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + pymodbus[simulator]==3.13.0) + docker-compose.yml with four compose profiles (standard / dl205 / mitsubishi / s7_1500) backed by the existing profile JSONs copied under Docker/profiles/ as canonical; native fallback in Pymodbus/ retained with the same JSON set (symlink-equivalent — manual re-sync when profiles change, noted in both READMEs). Port 5020 unchanged so MODBUS_SIM_ENDPOINT + ModbusSimulatorFixture work without code change. Dropped the --no_http CLI arg the old serve.ps1 + compose draft passed — pymodbus 3.13 doesn't recognize it; the simulator's http ui just binds inside the container where nothing maps it out and costs nothing. S7 — new tests/ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + python-snap7>=2.0) + docker-compose.yml with one s7_1500 compose profile; copies the existing server.py shim + s7_1500.json seed profile; runs python -u server.py ... --port 1102. Native fallback in PythonSnap7/ retained. Port 1102 unchanged. AB CIP — hardest because ab_server is a source-only C tool in libplctag's src/tools/ab_server/. New tests/ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests/Docker/ Dockerfile is multi-stage: build stage (debian:bookworm-slim + build-essential + cmake) clones libplctag at a pinned tag + cmake --build build --target ab_server; runtime stage (debian:bookworm-slim) copies just the binary from /src/build/bin_dist/ab_server. docker-compose.yml ships four compose profiles (controllogix / compactlogix / micro800 / guardlogix) with per-family ab_server CLI args matching AbServerProfile.cs. AbServerFixture updated: tries TCP probe on 127.0.0.1:44818 first (Docker path) + spawns the native binary only as fallback when no listener is there. AB_SERVER_ENDPOINT env var supported for pointing at a real PLC. AbServerFact/Theory attributes updated to IsServerAvailable() which accepts any of: live listener on 44818, AB_SERVER_ENDPOINT set, or binary on PATH. Required two CLI-compat fixes to ab_server's argument expectations that the existing native profile never caught because it was never actually run at CI: --plc is case-sensitive (ControlLogix not controllogix), CIP tags need [size] bracket notation (DINT[1] not bare DINT), ControlLogix also requires --path=1,0. Compose files carry the corrected flags; the existing native-path AbServerProfile.cs was never invoked in practice so we don't rewrite it here. Micro800 now uses the --plc=Micro800 mode rather than falling back to ControlLogix emulation — ab_server does have the dedicated mode, the old Notes saying otherwise were wrong. Updated docs: three fixture coverage docs (Modbus-Test-Fixture.md, S7-Test-Fixture.md, AbServer-Test-Fixture.md) flip their "What the fixture is" section from native-only to Docker-primary-with-native-fallback; dev-environment.md §Resource Inventory replaces the old ambiguous "Docker Desktop + ab_server native" mix with four per-driver rows (each listing the image, compose file, compose profiles, port, credentials) + a new Docker fixtures — quick reference subsection giving the one-line docker compose -f <…> --profile <…> up for each driver + the env-var override names + the native fallback install recipes. drivers/README.md coverage map table updated — Modbus/AB CIP/S7 entries now read "Dockerized …" consistent with OpcUaClient's line. Verified end-to-end against live containers: Modbus DL205 smoke 1/1, S7 3/3, AB CIP ControlLogix 4/4 (all family theory rows). Container lifecycle clean (up/test/down, no leaked state). Every fixture keeps its skip-when-absent probe + env-var endpoint override so dotnet test on a fresh clone without Docker running still gets a green run.
docker compose up. Modbus — new tests/ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + pymodbus[simulator]==3.13.0) + docker-compose.yml with four compose profiles (standard / dl205 / mitsubishi / s7_1500) backed by the existing profile JSONs copied under Docker/profiles/ as canonical; native fallback in Pymodbus/ retained with the same JSON set (symlink-equivalent — manual re-sync when profiles change, noted in both READMEs). Port 5020 unchanged so MODBUS_SIM_ENDPOINT + ModbusSimulatorFixture work without code change. Dropped the --no_http CLI arg the old serve.ps1 + compose draft passed — pymodbus 3.13 doesn't recognize it; the simulator's http ui just binds inside the container where nothing maps it out and costs nothing. S7 — new tests/ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + python-snap7>=2.0) + docker-compose.yml with one s7_1500 compose profile; copies the existing server.py shim + s7_1500.json seed profile; runs python -u server.py ... --port 1102. Native fallback in PythonSnap7/ retained. Port 1102 unchanged. AB CIP — hardest because ab_server is a source-only C tool in libplctag's src/tools/ab_server/. New tests/ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests/Docker/ Dockerfile is multi-stage: build stage (debian:bookworm-slim + build-essential + cmake) clones libplctag at a pinned tag + cmake --build build --target ab_server; runtime stage (debian:bookworm-slim) copies just the binary from /src/build/bin_dist/ab_server. docker-compose.yml ships four compose profiles (controllogix / compactlogix / micro800 / guardlogix) with per-family ab_server CLI args matching AbServerProfile.cs. AbServerFixture updated: tries TCP probe on 127.0.0.1:44818 first (Docker path) + spawns the native binary only as fallback when no listener is there. AB_SERVER_ENDPOINT env var supported for pointing at a real PLC. AbServerFact/Theory attributes updated to IsServerAvailable() which accepts any of: live listener on 44818, AB_SERVER_ENDPOINT set, or binary on PATH. Required two CLI-compat fixes to ab_server's argument expectations that the existing native profile never caught because it was never actually run at CI: --plc is case-sensitive (ControlLogix not controllogix), CIP tags need [size] bracket notation (DINT[1] not bare DINT), ControlLogix also requires --path=1,0. Compose files carry the corrected flags; the existing native-path AbServerProfile.cs was never invoked in practice so we don't rewrite it here. Micro800 now uses the --plc=Micro800 mode rather than falling back to ControlLogix emulation — ab_server does have the dedicated mode, the old Notes saying otherwise were wrong. Updated docs: three fixture coverage docs (Modbus-Test-Fixture.md, S7-Test-Fixture.md, AbServer-Test-Fixture.md) flip their "What the fixture is" section from native-only to Docker-primary-with-native-fallback; dev-environment.md §Resource Inventory replaces the old ambiguous "Docker Desktop + ab_server native" mix with four per-driver rows (each listing the image, compose file, compose profiles, port, credentials) + a new Docker fixtures — quick reference subsection giving the one-line docker compose -f <…> --profile <…> up for each driver + the env-var override names + the native fallback install recipes. drivers/README.md coverage map table updated — Modbus/AB CIP/S7 entries now read "Dockerized …" consistent with OpcUaClient's line. Verified end-to-end against live containers: Modbus DL205 smoke 1/1, S7 3/3, AB CIP ControlLogix 4/4 (all family theory rows). Container lifecycle clean (up/test/down, no leaked state). Every fixture keeps its skip-when-absent probe + env-var endpoint override so dotnet test on a fresh clone without Docker running still gets a green run.
docker compose up. Modbus — new tests/ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + pymodbus[simulator]==3.13.0) + docker-compose.yml with four compose profiles (standard / dl205 / mitsubishi / s7_1500) backed by the existing profile JSONs copied under Docker/profiles/ as canonical; native fallback in Pymodbus/ retained with the same JSON set (symlink-equivalent — manual re-sync when profiles change, noted in both READMEs). Port 5020 unchanged so MODBUS_SIM_ENDPOINT + ModbusSimulatorFixture work without code change. Dropped the --no_http CLI arg the old serve.ps1 + compose draft passed — pymodbus 3.13 doesn't recognize it; the simulator's http ui just binds inside the container where nothing maps it out and costs nothing. S7 — new tests/ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + python-snap7>=2.0) + docker-compose.yml with one s7_1500 compose profile; copies the existing server.py shim + s7_1500.json seed profile; runs python -u server.py ... --port 1102. Native fallback in PythonSnap7/ retained. Port 1102 unchanged. AB CIP — hardest because ab_server is a source-only C tool in libplctag's src/tools/ab_server/. New tests/ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests/Docker/ Dockerfile is multi-stage: build stage (debian:bookworm-slim + build-essential + cmake) clones libplctag at a pinned tag + cmake --build build --target ab_server; runtime stage (debian:bookworm-slim) copies just the binary from /src/build/bin_dist/ab_server. docker-compose.yml ships four compose profiles (controllogix / compactlogix / micro800 / guardlogix) with per-family ab_server CLI args matching AbServerProfile.cs. AbServerFixture updated: tries TCP probe on 127.0.0.1:44818 first (Docker path) + spawns the native binary only as fallback when no listener is there. AB_SERVER_ENDPOINT env var supported for pointing at a real PLC. AbServerFact/Theory attributes updated to IsServerAvailable() which accepts any of: live listener on 44818, AB_SERVER_ENDPOINT set, or binary on PATH. Required two CLI-compat fixes to ab_server's argument expectations that the existing native profile never caught because it was never actually run at CI: --plc is case-sensitive (ControlLogix not controllogix), CIP tags need [size] bracket notation (DINT[1] not bare DINT), ControlLogix also requires --path=1,0. Compose files carry the corrected flags; the existing native-path AbServerProfile.cs was never invoked in practice so we don't rewrite it here. Micro800 now uses the --plc=Micro800 mode rather than falling back to ControlLogix emulation — ab_server does have the dedicated mode, the old Notes saying otherwise were wrong. Updated docs: three fixture coverage docs (Modbus-Test-Fixture.md, S7-Test-Fixture.md, AbServer-Test-Fixture.md) flip their "What the fixture is" section from native-only to Docker-primary-with-native-fallback; dev-environment.md §Resource Inventory replaces the old ambiguous "Docker Desktop + ab_server native" mix with four per-driver rows (each listing the image, compose file, compose profiles, port, credentials) + a new Docker fixtures — quick reference subsection giving the one-line docker compose -f <…> --profile <…> up for each driver + the env-var override names + the native fallback install recipes. drivers/README.md coverage map table updated — Modbus/AB CIP/S7 entries now read "Dockerized …" consistent with OpcUaClient's line. Verified end-to-end against live containers: Modbus DL205 smoke 1/1, S7 3/3, AB CIP ControlLogix 4/4 (all family theory rows). Container lifecycle clean (up/test/down, no leaked state). Every fixture keeps its skip-when-absent probe + env-var endpoint override so dotnet test on a fresh clone without Docker running still gets a green run.
docker compose up. Modbus — new tests/ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + pymodbus[simulator]==3.13.0) + docker-compose.yml with four compose profiles (standard / dl205 / mitsubishi / s7_1500) backed by the existing profile JSONs copied under Docker/profiles/ as canonical; native fallback in Pymodbus/ retained with the same JSON set (symlink-equivalent — manual re-sync when profiles change, noted in both READMEs). Port 5020 unchanged so MODBUS_SIM_ENDPOINT + ModbusSimulatorFixture work without code change. Dropped the --no_http CLI arg the old serve.ps1 + compose draft passed — pymodbus 3.13 doesn't recognize it; the simulator's http ui just binds inside the container where nothing maps it out and costs nothing. S7 — new tests/ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + python-snap7>=2.0) + docker-compose.yml with one s7_1500 compose profile; copies the existing server.py shim + s7_1500.json seed profile; runs python -u server.py ... --port 1102. Native fallback in PythonSnap7/ retained. Port 1102 unchanged. AB CIP — hardest because ab_server is a source-only C tool in libplctag's src/tools/ab_server/. New tests/ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests/Docker/ Dockerfile is multi-stage: build stage (debian:bookworm-slim + build-essential + cmake) clones libplctag at a pinned tag + cmake --build build --target ab_server; runtime stage (debian:bookworm-slim) copies just the binary from /src/build/bin_dist/ab_server. docker-compose.yml ships four compose profiles (controllogix / compactlogix / micro800 / guardlogix) with per-family ab_server CLI args matching AbServerProfile.cs. AbServerFixture updated: tries TCP probe on 127.0.0.1:44818 first (Docker path) + spawns the native binary only as fallback when no listener is there. AB_SERVER_ENDPOINT env var supported for pointing at a real PLC. AbServerFact/Theory attributes updated to IsServerAvailable() which accepts any of: live listener on 44818, AB_SERVER_ENDPOINT set, or binary on PATH. Required two CLI-compat fixes to ab_server's argument expectations that the existing native profile never caught because it was never actually run at CI: --plc is case-sensitive (ControlLogix not controllogix), CIP tags need [size] bracket notation (DINT[1] not bare DINT), ControlLogix also requires --path=1,0. Compose files carry the corrected flags; the existing native-path AbServerProfile.cs was never invoked in practice so we don't rewrite it here. Micro800 now uses the --plc=Micro800 mode rather than falling back to ControlLogix emulation — ab_server does have the dedicated mode, the old Notes saying otherwise were wrong. Updated docs: three fixture coverage docs (Modbus-Test-Fixture.md, S7-Test-Fixture.md, AbServer-Test-Fixture.md) flip their "What the fixture is" section from native-only to Docker-primary-with-native-fallback; dev-environment.md §Resource Inventory replaces the old ambiguous "Docker Desktop + ab_server native" mix with four per-driver rows (each listing the image, compose file, compose profiles, port, credentials) + a new Docker fixtures — quick reference subsection giving the one-line docker compose -f <…> --profile <…> up for each driver + the env-var override names + the native fallback install recipes. drivers/README.md coverage map table updated — Modbus/AB CIP/S7 entries now read "Dockerized …" consistent with OpcUaClient's line. Verified end-to-end against live containers: Modbus DL205 smoke 1/1, S7 3/3, AB CIP ControlLogix 4/4 (all family theory rows). Container lifecycle clean (up/test/down, no leaked state). Every fixture keeps its skip-when-absent probe + env-var endpoint override so dotnet test on a fresh clone without Docker running still gets a green run.
docker compose up. Modbus — new tests/ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + pymodbus[simulator]==3.13.0) + docker-compose.yml with four compose profiles (standard / dl205 / mitsubishi / s7_1500) backed by the existing profile JSONs copied under Docker/profiles/ as canonical; native fallback in Pymodbus/ retained with the same JSON set (symlink-equivalent — manual re-sync when profiles change, noted in both READMEs). Port 5020 unchanged so MODBUS_SIM_ENDPOINT + ModbusSimulatorFixture work without code change. Dropped the --no_http CLI arg the old serve.ps1 + compose draft passed — pymodbus 3.13 doesn't recognize it; the simulator's http ui just binds inside the container where nothing maps it out and costs nothing. S7 — new tests/ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests/Docker/ with Dockerfile (python:3.12-slim-bookworm + python-snap7>=2.0) + docker-compose.yml with one s7_1500 compose profile; copies the existing server.py shim + s7_1500.json seed profile; runs python -u server.py ... --port 1102. Native fallback in PythonSnap7/ retained. Port 1102 unchanged. AB CIP — hardest because ab_server is a source-only C tool in libplctag's src/tools/ab_server/. New tests/ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests/Docker/ Dockerfile is multi-stage: build stage (debian:bookworm-slim + build-essential + cmake) clones libplctag at a pinned tag + cmake --build build --target ab_server; runtime stage (debian:bookworm-slim) copies just the binary from /src/build/bin_dist/ab_server. docker-compose.yml ships four compose profiles (controllogix / compactlogix / micro800 / guardlogix) with per-family ab_server CLI args matching AbServerProfile.cs. AbServerFixture updated: tries TCP probe on 127.0.0.1:44818 first (Docker path) + spawns the native binary only as fallback when no listener is there. AB_SERVER_ENDPOINT env var supported for pointing at a real PLC. AbServerFact/Theory attributes updated to IsServerAvailable() which accepts any of: live listener on 44818, AB_SERVER_ENDPOINT set, or binary on PATH. Required two CLI-compat fixes to ab_server's argument expectations that the existing native profile never caught because it was never actually run at CI: --plc is case-sensitive (ControlLogix not controllogix), CIP tags need [size] bracket notation (DINT[1] not bare DINT), ControlLogix also requires --path=1,0. Compose files carry the corrected flags; the existing native-path AbServerProfile.cs was never invoked in practice so we don't rewrite it here. Micro800 now uses the --plc=Micro800 mode rather than falling back to ControlLogix emulation — ab_server does have the dedicated mode, the old Notes saying otherwise were wrong. Updated docs: three fixture coverage docs (Modbus-Test-Fixture.md, S7-Test-Fixture.md, AbServer-Test-Fixture.md) flip their "What the fixture is" section from native-only to Docker-primary-with-native-fallback; dev-environment.md §Resource Inventory replaces the old ambiguous "Docker Desktop + ab_server native" mix with four per-driver rows (each listing the image, compose file, compose profiles, port, credentials) + a new Docker fixtures — quick reference subsection giving the one-line docker compose -f <…> --profile <…> up for each driver + the env-var override names + the native fallback install recipes. drivers/README.md coverage map table updated — Modbus/AB CIP/S7 entries now read "Dockerized …" consistent with OpcUaClient's line. Verified end-to-end against live containers: Modbus DL205 smoke 1/1, S7 3/3, AB CIP ControlLogix 4/4 (all family theory rows). Container lifecycle clean (up/test/down, no leaked state). Every fixture keeps its skip-when-absent probe + env-var endpoint override so dotnet test on a fresh clone without Docker running still gets a green run.
S7 integration-test fixture — python-snap7 (Docker)
python-snap7 Server class
wrapped in a pinned python:3.12-slim-bookworm image. Docker is the
primary launcher; the native-Python fallback under
../PythonSnap7/ is kept for contributors who prefer
to avoid Docker locally.
| File | Purpose |
|---|---|
Dockerfile |
python:3.12-slim-bookworm + python-snap7>=2.0 + the server shim + the profile JSONs |
docker-compose.yml |
One service per profile; currently only s7_1500 |
server.py |
Same Python shim the native fallback uses — copy kept in the build context |
profiles/*.json |
Area-seed definitions (DB1 / MB layouts with typed seeds) |
Run
From the repo root:
docker compose -f tests\ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests\Docker\docker-compose.yml --profile s7_1500 up
Detached + stop:
docker compose -f tests\...\Docker\docker-compose.yml --profile s7_1500 up -d
docker compose -f tests\...\Docker\docker-compose.yml --profile s7_1500 down
Endpoint
- Default:
localhost:1102(non-privileged; sidesteps Windows Firewall prompt + Linux's root-required bind on port 102). - Override with
S7_SIM_ENDPOINTto point at a real S7 CPU on:102. - The driver's S7DriverOptions.Port flows through S7netplus's 5-arg
Plc(CpuType, host, port, rack, slot)ctor so the non-standard port works end-to-end.
Run the integration tests
In a separate shell with the container up:
cd C:\Users\dohertj2\Desktop\lmxopcua
dotnet test tests\ZB.MOM.WW.OtOpcUa.Driver.S7.IntegrationTests
Snap7ServerFixture probes localhost:1102 at collection init + records
a SkipReason when unreachable, so tests stay green on a fresh clone
without Docker running.
What's encoded in profiles/s7_1500.json
DB1 (1024 bytes) + MB (256 bytes) with typed seeds at known offsets:
| Address | Type | Seed | Purpose |
|---|---|---|---|
DB1.DBW0 |
u16 | 4242 |
read-back probe |
DB1.DBW10 |
i16 | -12345 |
smoke i16 read |
DB1.DBD20 |
i32 | 1234567890 |
smoke i32 read |
DB1.DBD30 |
f32 | 3.14159 |
smoke f32 read (big-endian) |
DB1.DBX50.3 |
bool | true |
smoke bool read at bit 3 |
DB1.DBW100 |
u16 | 0 |
scratch for write-then-read |
DB1.STRING[200] |
S7 STRING | "Hello" |
S7 STRING read |
MW0 |
u16 | 1 |
S7ProbeOptions.ProbeAddress default |
Seed types supported: u8, i8, u16, i16, u32, i32, f32,
bool (with "bit": 0..7), ascii (S7 STRING).
Known limitations
From the snap7.server.Server docstring upstream:
"Legacy S7 server implementation. Emulates a Siemens S7 PLC for testing and development purposes. [...] pure Python emulator implementation that simulates PLC behaviour for protocol compliance testing rather than full industrial-grade functionality."
Not exercised here — needs a lab rig:
- S7-1500 Optimized-DB symbolic access
- PG / OP / S7-Basic session-type differentiation
- PUT/GET-disabled-by-default enforcement
See docs/drivers/S7-Test-Fixture.md
for the full coverage map.
Native-Python fallback
../PythonSnap7/ has the same server.py + profile
JSON launched via local Python install (pip install python-snap7).
Kept for contributors who prefer native.
References
- python-snap7 GitHub
../PythonSnap7/README.md— native launcherdocs/drivers/S7-Test-Fixture.md— coverage mapdocs/v2/dev-environment.md§Docker fixtures