mxaccessgw/docs/CrossLanguageSmokeMatrix.md

Cross-Language Smoke Matrix

The cross-language smoke matrix defines the documented commands used to compare official clients against the same live gateway flow. It is a repository validation fixture and command reference; normal unit tests validate the matrix shape without connecting to a gateway.

The matrix lives in clients/proto/fixtures/smoke/cross-language-smoke-matrix.json.

Scope

The matrix covers the supported client languages:

• .NET
• Go
• Rust
• Python
• Java

Each client entry defines commands for the same required operation sequence:

1. open-session
2. register
3. add-item
4. advise
5. stream-events
6. close-session

The optional write command is documented separately because writing changes provider state and should only run when the operator supplies a safe test value.

When stream-events is resumed with an after_worker_sequence cursor that predates the oldest event still in the gateway's replay ring, the gateway emits a single ReplayGap sentinel at the head of the stream. Every client surfaces this as a distinct, typed, non-terminal signal (see each client README); the resume contract is after_worker_sequence = oldest_available_sequence - 1, and it holds even when the ring has been emptied entirely by age eviction — the gateway then reports the next deliverable sequence rather than 0 (see Sessions). The default smoke sequence opens a fresh stream (no cursor) and does not exercise the gap path; a resume-with-gap fixture case is tracked separately (TST-24).

The CLIs differ in how they print that library-level signal. Three of them consume the typed gap and emit a dedicated row rather than a degenerate event row; the other two hand the raw sentinel MxEvent straight to the formatter, so they print the sentinel itself, whose replayGap field carries the same cursors:

CLI	Text mode	JSON mode
mxgw-rs (Rust, canonical)	REPLAY_GAP requested_after=<n> oldest_available=<n>	{"replayGap": {"requestedAfterSequence": <n>, "oldestAvailableSequence": <n>}} as one entry of the events array
mxgw-go (Go)	REPLAY_GAP requested_after=<n> oldest_available=<n>	one {"replayGap": {"requestedAfterSequence": <n>, "oldestAvailableSequence": <n>}} line, counted toward -limit like any other row
mxgw-py (Python)	same JSON dump as --json	{"replayGap": {"requestedAfterSequence": <n>, "oldestAvailableSequence": <n>}} as one entry of the events array
mxgw-dotnet (.NET)	the raw sentinel MxEvent as protobuf JSON, including its replayGap field	same, as one entry of the events array
mxgw-java (Java)	the sentinel's worker_sequence and family (0 MX_EVENT_FAMILY_UNSPECIFIED)	the raw sentinel MxEvent as protobuf JSON, including its replayGap field

Rust, Go, and Python emit the same two key names and, deliberately, the same JSON value types: the cursors are JSON numbers (7), not strings. That is why the Go CLI types the row by hand instead of marshalling ReplayGap with protojson — the proto3 JSON mapping renders 64-bit integers as strings ("7"), which is also why the .NET and Java rows, which pass the sentinel through a protobuf JSON formatter, carry quoted cursors. A matrix runner must therefore compare parsed values, not raw bytes, and must not assume the same value type across all five CLIs.

Two further formatting differences among the three canonical CLIs, none of them semantic: Python sorts object keys and uses ", " / ": " separators (json.dumps(..., sort_keys=True)), while Rust and Go emit compact, declaration-ordered JSON; and the row sits alone on its own line for Go and for Rust's --jsonl, but inside an events array for Python and for Rust's aggregate --json.

Integration Gate

Cross-language smoke execution is opt-in. Runners should skip the matrix unless this variable is set:

$env:MXGATEWAY_INTEGRATION = "1"

The shared inputs are:

Variable	Default	Purpose
MXGATEWAY_ENDPOINT	localhost:5000	Gateway endpoint used by client CLIs.
MXGATEWAY_API_KEY	Empty	API key source for authenticated gateway deployments.
MXGATEWAY_TEST_ITEM	TestChildObject.TestInt	MXAccess item used by add-item.
MXGATEWAY_TEST_WRITE_VALUE	Empty	Enables the optional write step when set by a runner.

The commands in the matrix use MXGATEWAY_API_KEY through each CLI's api-key-env flag. They must not embed bearer tokens or raw API keys.

Credential contract for authenticate-user

Every CLI resolves the MXAccess verify-user credential the same way, so one exported variable drives the same operator workflow in all five languages:

Variable	Default	Purpose
MXGATEWAY_VERIFY_PASSWORD	Empty	Verify-user credential read by authenticate-user when --password is omitted.

• Flags are --password (Go: -password) for an explicit value and --password-env (Go: -password-env) for the name of the environment variable, defaulting to MXGATEWAY_VERIFY_PASSWORD.
• Resolution order is flag, then environment variable. Prefer the variable: the flag puts the secret in shell history and the process table.
• A resolved credential that is missing or empty is a usage error. The CLI fails fast before dialing rather than authenticating with an empty password, and the error names only the flag and the variable — never the value. Nothing echoes the credential to stdout, stderr, or logs.

This is CLI argument validation, not an MXAccess parity exception: the client libraries still transmit whatever credential they are given. Only the operator tools refuse to fabricate an empty one.

The .NET CLI accepted --verify-user-password, --verify-user-password-env, and MXGATEWAY_VERIFY_USER_PASSWORD before this contract was unified. Those names remain as deprecated aliases for one release; new scripts must use the canonical names above. The full .NET resolution order is --password, --verify-user-password, the variable named by --password-env (or the deprecated --verify-user-password-env, default MXGATEWAY_VERIFY_PASSWORD), then MXGATEWAY_VERIFY_USER_PASSWORD.

TLS variant

The matrix runs over plaintext (h2c) by default. A TLS variant exists but stays a manual/opt-in run, consistent with the gate above, because it needs the gateway started with an HTTPS endpoint (an https:// MXGATEWAY_ENDPOINT) and each CLI switched to its TLS flag (--tls / -tls / --plaintext=false / plaintext=False). The clients are lenient by default and accept the gateway's auto-generated self-signed certificate without extra trust setup, except the Rust CLI, which is pin-only and needs --ca-file or --require-certificate-validation (and Python uses trust-on-first-use). See Gateway Configuration — Automatic self-signed certificate and each client README for the per-client TLS flags.

JSON Comparison

Every command in the matrix requests JSON output. A runner can compare the normalized smoke record across languages with these fields:

• language,
• operation,
• session id,
• server handle,
• item handle,
• event count,
• event family,
• worker sequence,
• protocol status,
• HRESULT,
• status arrays,
• close status.

Failure output must include the client language, endpoint, and redacted auth context. Auth context identifies the source, such as MXGATEWAY_API_KEY, but does not include the secret value.

Bundled Smoke Commands

Each client also exposes a bundled smoke command. Those commands are useful for quick local checks, but the full cross-language matrix uses explicit operation commands because not every bundled smoke command streams events yet. The explicit sequence remains the parity baseline for issue-level validation.

Per-CLI Subcommand Coverage

The matrix sequence itself is available everywhere, but the later single-item session commands were not added to every CLI at the same time. A runner that reaches beyond the required sequence must branch on language, so the current deltas are specified here rather than left to be discovered:

Subcommand	.NET	Rust	Go	Python	Java
unregister	yes	yes	no	no	no
add-buffered-item	yes	no	no	no	no
set-buffered-update-interval	yes	no	no	no	no
suspend	yes	no	no	no	no
activate	yes	no	no	no	no
write-secured	yes	yes	yes	yes	yes
write-secured2	yes	no	no	no	no
authenticate-user	yes	yes	yes	yes	yes
archestra-user-to-id	yes	no	no	no	no

Only .NET exposes all nine. Rust adds unregister and the credential pair; Go, Python, and Java expose the credential pair only. Every gap is CLI surface only — all five libraries implement all nine typed helpers, so a gap is a missing operator command, never a missing capability. Levelling the CLIs is separate feature work and is not tracked as a defect here.

Validation

Run the matrix shape tests after changing the smoke matrix:

dotnet test src/ZB.MOM.WW.MxGateway.Tests/ZB.MOM.WW.MxGateway.Tests.csproj --filter FullyQualifiedName~CrossLanguageSmokeMatrixTests

Live execution remains a separate opt-in step because it depends on a running gateway, the installed MXAccess worker path, and provider state.

Related Documentation

• Gateway Testing
• Client Libraries Detailed Design
• Client Proto Generation