add MeasurementRepository

src/main/kotlin/ltd/hlaeja/repository/MeasurementRepository.kt

@@ -0,0 +1,44 @@
+package ltd.hlaeja.repository
+
+import com.influxdb.client.InfluxDBClient
+import com.influxdb.client.write.Point
+import com.influxdb.query.FluxTable
+import java.util.UUID
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import ltd.hlaeja.properties.InfluxDbProperties
+import org.springframework.stereotype.Repository
+
+@Repository
+class MeasurementRepository(
+    private val influxDBClient: InfluxDBClient,
+    private val properties: InfluxDbProperties,
+) {
+
+    companion object {
+        const val BY_NODE_QUERY: String = """
+          from(bucket: "%s")
+            |> range(start: -1y)
+            |> filter(fn: (r) => r["_measurement"] == "%s")
+            |> filter(fn: (r) => r["node"] == "%s")
+            |> group(columns: ["_field"])
+            |> sort(columns: ["_time"], desc: true)
+            |> limit(n: 1)
+        """
+    }
+
+    suspend fun save(
+        point: Point,
+    ) = withContext(Dispatchers.IO) {
+        influxDBClient.makeWriteApi().writePoint(point)
+    }
+
+    suspend fun getByNode(
+        client: UUID,
+        device: UUID,
+    ): MutableList<FluxTable> = influxDBClient.queryApi
+        .query(
+            BY_NODE_QUERY.format(properties.bucket, client, device).trimIndent(),
+            properties.org,
+        )
+}