#56 fixing a problem where the host object (which now includes timezo…

…ne) is used to work out the index offset to write temperatures to the RRD and not just the host name

src/main/scala/bad/robot/temperature/rrd/Host.scala

@@ -14,12 +14,12 @@ object Host {
   }
 
   def local = Host(InetAddress.getLocalHost.getHostName, localUtcOffset)
-  
+
   implicit val encoder = deriveEncoder[Host]
   implicit val decoder = deriveDecoder[Host]
 
   // another arbitrary constraint of rrd4j; data source names can only be a max of 20 characters
-  def trim(name: String) =name.take(20 - "-sensor-x".length)
+  def trim(name: String) = name.take(20 - "-sensor-x".length)
 }
 
 case class Host(name: String, utcOffset: Option[String])

src/main/scala/bad/robot/temperature/rrd/Rrd.scala

@@ -3,5 +3,5 @@ package bad.robot.temperature.rrd
 import bad.robot.temperature.{Measurement, TemperatureWriter}
 
 case class Rrd(monitored: List[Host]) extends TemperatureWriter {
-  def write(measurement: Measurement) = RrdUpdate(monitored, measurement).apply()
+  def write(measurement: Measurement) = RrdUpdate(monitored).apply(measurement)
 }

src/main/scala/bad/robot/temperature/rrd/RrdUpdate.scala

@@ -4,29 +4,38 @@ import bad.robot.logging.Log
 import bad.robot.temperature.{Error, Measurement, RrdError, SensorReading, Temperature, _}
 import org.rrd4j.core.RrdDb
 
-import scalaz.\/
+import scalaz.{\/, \/-}
 import scalaz.\/.fromTryCatchNonFatal
 
-case class RrdUpdate(monitored: List[Host], measurement: Measurement) {
+case class RrdUpdate(monitored: List[Host]) {
 
   private val UnknownValues = List().padTo(monitored.size * RrdFile.MaxSensors, SensorReading("Unknown", Temperature(Double.NaN)))
 
-  def apply(): Error \/ Unit = {
+  def apply(measurement: Measurement): Error \/ Unit = {
+    indexOf(measurement) match {
+      case Some(index) => writeTemperatureAt(measurement, index)
+      case None        => Log.error(s"Unable to write temperature to RRD: '${measurement.host.name}' not setup as an archive"); \/-(())
+    }
+  }
+
+  private def writeTemperatureAt(measurement: Measurement, index: Int) = {
     fromTryCatchNonFatal {
       val database = new RrdDb(RrdFile.file)
       val sample = database.createSample()
-      val indexOf = monitored.indexOf(measurement.host)
-      Log.debug(s"Index of ${measurement.host.name } is $indexOf (-1 means it couldn't be found)")
-      val temperatures = UnknownValues.patch(indexOf * RrdFile.MaxSensors, measurement.temperatures, measurement.temperatures.size)
+      val temperatures = UnknownValues.patch(index * RrdFile.MaxSensors, measurement.temperatures, measurement.temperatures.size)
       sample.setValues(database, measurement.time, temperatures.map(_.temperature.celsius): _*)
-      Log.debug(s"rrd -> ${measurement.host.name} ${measurement.time} ${temperatures.map(t => t.name + " " + t.temperature.celsius).mkString(", ")}")
       database.close()
     }.leftMap(error => {
       RrdError(messageOrStackTrace(error))
     })
   }
 
-  def messageOrStackTrace(error: Throwable): String = {
-    Option(error.getMessage).getOrElse(stackTraceOf(error)) 
+  private def indexOf(measurement: Measurement): Option[Int] = {
+    val index = monitored.map(_.name).indexOf(measurement.host.name)
+    if (index == -1) None else Some(index)
+  }
+
+  private def messageOrStackTrace(error: Throwable): String = {
+    Option(error.getMessage).getOrElse(stackTraceOf(error))
   }
 }

src/test/scala/bad/robot/temperature/rrd/Example.scala

@@ -48,14 +48,14 @@ object Example extends App {
 
     times.zip(temperatures).foreach({
       case (time, (temperature1, temperature2)) => {
-        handleError(RrdUpdate(hosts, Measurement(hosts(0), time, List(
+        handleError(RrdUpdate(hosts).apply(Measurement(hosts(0), time, List(
           SensorReading("?", Temperature(temperature1)),
           SensorReading("?", Temperature(temperature1 + 6.3)))
-        )).apply())
-        handleError(RrdUpdate(hosts, Measurement(hosts(1), time + 1, List(
+        )))
+        handleError(RrdUpdate(hosts).apply(Measurement(hosts(1), time + 1, List(
           SensorReading("?", Temperature(temperature2)),
           SensorReading("?", Temperature(temperature2 + 1.3)))
-        )).apply())
+        )))
       }
     })