allowWrites is no longer inert: SqlDriver implements IWritable, default off.
- Gates (outermost first): node Writable + WriteOperate (server), driver
allowWrites, the tag's own TagConfig "writable": true (strict JSON boolean;
anything else refuses the tag, and the deploy gate says why), and a model that
names exactly one row — KeyValue, or WideRow by where-pair. topByTimestamp and
Query are BadNotWritable.
- SqlWritePlanner: the only statement a write can become is
UPDATE <table> SET <value col> = @v WHERE <key col> = @k, built from the
catalog-gate-canonical identifiers (dialect-quoted) with value and key bound;
value-before-key marker order so positional ODBC binds correctly. No authored
write SQL, INSERT, UPSERT or procedure.
- Executed in a transaction that commits only when exactly one row was touched:
0 rows -> BadNoData (never inserts), >1 -> rolled back, BadConfigurationError,
unknown count -> rolled back, BadNotSupported. Bounded by operationTimeout;
provider errors -> BadCommunicationError; health untouched.
- Discovery advertises Operate only where a write could succeed.
- AdminUI: driver form's Allow writes switch is live; tag editor gains a
per-tag write switch; model validates writable strictly (parity corpus).
- Factory no longer warns "allowWrites ignored"; it logs whether writes are on.
- Tests: SqlWriteTests (planner SQL/bind order/injection/coercion, every gate,
readback, absent key, two-row rollback, gate-rejected tag, discovery);
MySqlReadTests write legs against InnoDB (keyed row only, two-row rollback,
server-side grant refusal, default-off). Seed adds a setpoints table and the
one UPDATE grant.
(lmxopcua#753)
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
R06:M-5 made Sparkplug *Array leaves unbindable because the ingestor refused
them. The ingestor now decodes the packed bytes_value of all 13 array types
(new SparkplugArrayCodec: LE fixed widths, int64-ms DateTime, uint32-count +
MSB-first BooleanArray, NUL-terminated UTF-8 StringArray; golden vectors are
the spec's examples, reproduced byte-for-byte by SparkplugNet 1.3.10) and
publishes a typed 1-D array through the scalar coercion, all-or-nothing.
Shape uses the fleet's one array model: the tag's platform isArray/arrayLength
keys (ValueRank=1, ArrayDimensions=[arrayLength] or [0] = variable length).
The driver reads them with TagConfigIntent's exact semantics and never rejects
on them, so composer, driver, authoring model and deploy inspector agree
(MqttArrayShapeParityTests). Shape mismatch (array metric on a scalar tag, or
the reverse) is BadTypeMismatch - a String tag no longer gets the packed
buffer as base64; a malformed body or a length differing from a declared
arrayLength is BadDecodingError (MTConnect #627 verdict). Template/DataSet
members of an array type take the same path. Arrays stay read-only (encoder
refuses them; MQTT is not in DriverArrayWriteSupport).
Browser: array leaves are bindable again and state isArray in AddressFields;
the commit mapper writes "isArray": true (no arrayLength). Discovery reports
IsArray/ArrayDim. Docs: Mqtt.md "Array metrics", design table, drivers rule.
Tests: codec (golden + malformed), ingest through the real codec + Dispatch
(the project's MiniBroker never forwards a PUBLISH, so there is no in-process
broker harness), browse, discovery, commit mapper, parity corpus. Mutating the
fix back out fails 18 MQTT + 9 AdminUI tests.
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
Keeps the root CLAUDE.md lean by lazy-loading per-area detail (drivers, topology,
data-plane auth, alarms, historian) only when matching files are touched.
Joseph Doherty