# DC3 API Data

`dc3-api-data` defines gRPC contracts for values, commands, events, status, and system-health queries. Generated Java
types use `io.github.pnoker.api.center.data`; proto sources live under `src/main/protobuf/api/common/data/`.

## Services

| Service             | RPCs                                                     | Purpose                                            |
|---------------------|----------------------------------------------------------|----------------------------------------------------|
| `PointValueApi`     | `GetLastValue`, `ListHistoryValues`, `ListSeriesVolumes` | query point values and value-volume series         |
| `PointValueApi`     | `ReadCommand`, `WriteCommand`                            | submit point read/write commands                   |
| `CommandHistoryApi` | `CallCommand`, `GetByRecordId`, `List`                   | dispatch and query command history                 |
| `EventHistoryApi`   | `ReportEvent`, `GetByRecordId`, `List`                   | report and query event history                     |
| `StatusHealthApi`   | `DeviceStatusesByIds`, `DeviceStatusesByProfileId`       | query device status snapshots                      |
| `StatusHealthApi`   | `DriverStatusesByIds`, `DriverDeviceStatusSummary`       | query driver status snapshots and device summaries |
| `StatusHealthApi`   | `SystemHealth`                                           | query the platform health snapshot                 |

Single-result RPCs use `GetXxx`; collection/page results use `ListXxx` or an explicitly named status aggregation. Do not
reintroduce legacy `SelectXxx` names.

## Consumers and implementation

- `dc3-common-data` implements the data-side servers.
- `dc3-common-facade-grpc` wraps generated stubs in transport-independent facades.
- Manager and other business modules should call the facade API rather than construct channels directly.

All write/report requests must carry tenant context through the transport and into the business layer.

## Build and Verification

```bash
mvn -s .mvn/settings.xml -q -pl dc3-api/dc3-api-data -am compile
```

This contract module has no module-specific tests. Compile it after proto changes, then run the matching server and
facade tests in `dc3-common-data` and `dc3-common-facade-grpc`.