caching weather data

build.sbt

@@ -6,6 +6,8 @@ version := "1.0"
 
 scalaVersion := "2.12.1"
 
+mainClass := Some("de.ax.uwt.Launscha")
+
 resolvers += Resolver.sonatypeRepo("public")
 
 val circeVersion = "0.8.0"
@@ -25,5 +27,3 @@ libraryDependencies += "ch.qos.logback" % "logback-classic" % "1.2.3"
 libraryDependencies += "com.pi4j" % "pi4j-core" % "1.2-SNAPSHOT"
 
 libraryDependencies += "com.typesafe.scala-logging" %% "scala-logging" % "3.7.2"
-
-mainClass := Some("de.ax.uwt.Launscha")

src/main/scala/de/ax/uwt/UWT.scala

@@ -32,7 +32,7 @@ trait HasHistory {
   }
 }
 
-trait UWT extends HasHistory  with LazyLogging{
+trait UWT extends HasHistory with LazyLogging {
   implicit def i2p(i: Int): OutputPin
 
   implicit def i2p2(i: Int): InputPin
@@ -246,8 +246,7 @@ trait UWT extends HasHistory  with LazyLogging{
       dt.dateTime.isAfter(DateTime.now.minusHours(radius)) || dt.dateTime.isBefore(DateTime.now.plusHours(radius))
     })
     if (datas.isFailure) {
-      logger.info("error calculating weather")
-      datas.failed.foreach(_.printStackTrace())
+      datas.failed.foreach(e => logger.error("error calculating weather", e))
     }
     val rainLiters: Double = datas.map {
       _.map(dt => dt.precipIntensity * dt.precipProbability).sum

src/main/scala/de/ax/uwt/WeatherDataSet.scala

@@ -1,7 +1,6 @@
 package de.ax.uwt
 
 import java.io.File
-import java.security.Security
 
 import io.circe.generic.auto._
 import io.circe.parser._
@@ -10,7 +9,7 @@ import scala.io.Source
 import com.github.nscala_time.time.Imports._
 import com.typesafe.scalalogging.LazyLogging
 
-import scala.util.Try
+import scala.util.{Failure, Success, Try}
 
 /**
   * Created by nyxos on 20.06.17.
@@ -26,24 +25,40 @@ case class WeatherDataSet(currently: WeatherData, hourly: Entry, daily: Entry) {
 }
 
 object WeatherDataSet extends App with LazyLogging {
+  def getIt(): Try[WeatherDataSet] = {
+    Try {
+      import sys.process._
+      new File("tmpfile.json").delete()
+      val i: Int = (s"wget --timeout=60 -O tmpfile.json https://api.darksky.net/forecast/d9db5456106658292cbd4a6dc3b6e18a/50.8958998,7.30826,${(System.currentTimeMillis() / 1000).toLong}?lang=de&units=ca" !)
+      Source.fromFile("tmpfile.json", "UTF8").mkString
+    }.flatMap { s =>
+      decode[WeatherDataSet](s) match {
+        case Left(e) => Failure(e)
+        case Right(v) => Success(v)
+      }
+    }
+  }
 
-  Security.setProperty("jdk.tls.disabledAlgorithms", "")
+  var lastVal: Option[Try[WeatherDataSet]] = Option.empty
+  var lastUpdate = System.currentTimeMillis()
 
-  def getWeatherData: Try[WeatherDataSet] = Try {
-    import sys.process._
-    new File("tmpfile.json").delete()
-    val i: Int = (s"wget --timeout=60 -O tmpfile.json https://api.darksky.net/forecast/d9db5456106658292cbd4a6dc3b6e18a/50.8958998,7.30826,${(System.currentTimeMillis() / 1000).toLong}?lang=de&units=ca" !)
-    Source.fromFile("tmpfile.json", "UTF8").mkString
-  }.flatMap { s =>
-    Try {
-      decode[WeatherDataSet](s).toOption.get
+  def getWeatherData: Try[WeatherDataSet] = {
+    if (System.currentTimeMillis() - lastUpdate > (1000 * 60 * 60 * 2)) {
+      lastVal = Option.empty
     }
+    if (lastVal.forall(_.isFailure)) {
+      lastVal = Some(getIt())
+      lastUpdate = System.currentTimeMillis()
+    }
+    lastVal.getOrElse(Failure(new Exception("no cached weather data")))
   }
 
   getWeatherData.map { ds =>
     ds.hourly.data.filter(_.precipIntensity > 0).sortBy(_.dateTime).foreach(dt => logger.info(s"${Seq(dt.dateTime, dt.time, dt.precipIntensity, dt.precipIntensity, dt.precipProbability)}"))
     logger.info(s"got data count: ${ds.hourly.data.size}")
   }
-  logger.info(s"error: ${getWeatherData.failed.map(t => t.printStackTrace())}")
+
+  getWeatherData.failed.foreach(t => logger.error("weatherData Error", t))
+
   logger.info(s"getWeatherData:$getWeatherData")
 }