Controlling SVG output (#9)

* simplifying paths -> halving rough svg sizes

* better placement for simplifying function

* default directory + caching

* add control over output style

* add colors + leave default as is

* amended README.md to reflect all changes

README.md

@@ -118,12 +118,18 @@ That's it (_potentially_)! Eisner is capable of scanning your classes searching
 - fields or zero-arg methods that return `java.util.function.Supplier[org.apache.kafka.streams.Topology]`
 
 SVGs will be created for each, named after the class(+field/method) that defines the Topology.
-Currently, files are generated in `target/streams/_global/eisner/_global/streams/`.
+Files are generated by default in `target/eisner`.
+As long as topologies are not changed between subsequent runs of `eisner` (without `clean`), SVGs will not be regenerated.
 
 ## Tweaking with it
 
 Currently, Eisner supports a handful of options, namely:
 
+- `eisnerColorSink`: a `String` representing a [valid graphviz color](https://www.graphviz.org/doc/info/colors.html) used to draw sinks, defaults to `black`
+- `eisnerColorSubtopology`: a `String` representing a [valid graphviz color](https://www.graphviz.org/doc/info/colors.html) used to frame sub topologies, defaults to `lightgrey`
+- `eisnerColorTopic`: a `String` representing a [valid graphviz color](https://www.graphviz.org/doc/info/colors.html) used to draw topics, defaults to `black`
+- `eisnerRoughSVG`: a `Boolean` indicating whether Eisner should produce SVGs that look like hand drawings, defaults to `true`
+- `eisnerTargetDirectory`: a `File` which represents the directory where all SVGs will be saved into, defaults to `[current project]/target/eisner`
 - `eisnerTopologies`: a `Seq[String]` representing the fully qualified names of classes implementing `org.apache.kafka.streams.Topology`. This is useful in all cases where you need to control which SVGs get generated
 - `eisnerTopologiesSnippet`: a `Option[String]` representing a Scala snippet (inclusive of all necessary imports) that evaluates to a `Seq[(String, org.apache.kafka.streams.Topology)]`, where the `String` represents the `package.name` you want to give to the target file (dots will be converted to path separators). This is useful in all cases where automatic classloader scanning would not work, e.g. because you define your topologies in non zero-args methods or in fields that return `scala.Function1`. See [here](https://raw.githubusercontent.com/laserdisc-io/eisner/master/src/sbt-test/sbt-eisner/snippet/src/main/scala/snippet/EisnerTopology.scala) for a practical example.
 

build.sbt

@@ -24,6 +24,7 @@ lazy val eisner = project
     Compile / unmanagedSourceDirectories += (Compile / sourceDirectory).value / (if (isJDK9Plus) "scala-jdk9+" else "scala-jdk8-"),
     scalaVersion := `scala 2.12`,
     libraryDependencies ++= Seq(
+      "com.chuusai"            %% "shapeless"            % "2.3.3",
       "io.circe"               %% "circe-generic-extras" % "0.12.2",
       "io.circe"               %% "circe-parser"         % "0.12.3",
       "io.dylemma"             %% "xml-spac"             % "0.7",

src/main/scala/eisner/Config.scala

@@ -0,0 +1,3 @@
+package eisner
+
+final case class Config(subgraphColor: String, topicColor: String, storeColor: String)

src/main/scala/eisner/EisnerPlugin.scala

@@ -13,21 +13,31 @@ import scala.concurrent.ExecutionContext.Implicits.global
 
 object EisnerPlugin extends AutoPlugin with ReflectionSupport with SnippetSupport {
   object autoImport {
-    val eisnerTopologies = settingKey[Seq[String]]("The fully qualified names of classes implementing org.apache.kafka.streams.Topology")
+    val eisnerColorSink        = settingKey[String]("The color used to represent sinks, see https://www.graphviz.org/doc/info/colors.html")
+    val eisnerColorSubtopology = settingKey[String]("The color used to frame subtopologies, see https://www.graphviz.org/doc/info/colors.html")
+    val eisnerColorTopic       = settingKey[String]("The color used to represent topics, see https://www.graphviz.org/doc/info/colors.html")
+    val eisnerRoughSVG         = settingKey[Boolean]("The flag that controls whether to create SVG using pseudo hand-drawing")
+    val eisnerTargetDirectory  = settingKey[File]("The directory where to store the generated topologies")
+    val eisnerTopologies       = settingKey[Seq[String]]("The fully qualified names of classes implementing org.apache.kafka.streams.Topology")
     val eisnerTopologiesSnippet =
       settingKey[Option[String]]("A scala snippet (including all imports) that evaluates to a Seq[(String, org.apache.kafka.streams.Topology)]")
-    val eisner = taskKey[Seq[File]]("Generates one SVG for each org.apache.kafka.streams.Topology")
+    val eisner = taskKey[Set[File]]("Generates one SVG for each org.apache.kafka.streams.Topology")
   }
 
   import autoImport._
 
   override final def projectSettings: Seq[Setting[_]] = Seq(
+    eisnerColorSink := "black",
+    eisnerColorSubtopology := "lightgrey",
+    eisnerColorTopic := "black",
+    eisnerRoughSVG := true,
+    eisnerTargetDirectory := (Compile / target).value / "eisner",
     eisnerTopologies := Seq.empty,
     eisnerTopologiesSnippet := None,
     eisner := generate.dependsOn(Compile / compile).value
   )
 
-  private[this] final def generate: Def.Initialize[Task[Seq[File]]] = Def.taskDyn {
+  private[this] final def generate: Def.Initialize[Task[Set[File]]] = Def.taskDyn {
     val log      = streams.value.log
     val cacheDir = streams.value.cacheDirectory
 
@@ -59,18 +69,38 @@ object EisnerPlugin extends AutoPlugin with ReflectionSupport with SnippetSuppor
       Thread.currentThread.setContextClassLoader(classOf[PromiseException].getClassLoader)
 
       if (topologyDescriptions.nonEmpty) {
-        val fs = Future.traverse(topologyDescriptions) {
-          case (topologyName, topology) =>
-            topology.toSVG.map { svg =>
-              val f = new File(s"$cacheDir/${dotsToSlashes(topologyName)}.svg")
-              IO.write(f, svg)
-              f
-            }
+        val config = Config(eisnerColorSubtopology.value, eisnerColorTopic.value, eisnerColorSink.value)
+        val topologiesWithDots = topologyDescriptions
+          .map {
+            case (n, td) => (n, td, td.toDot(config))
+          }
+          .collect {
+            case (n, td, Right(d)) => (n, td, d)
+          }
+        val inputs = topologiesWithDots.map {
+          case (name, _, dot) =>
+            val f = new File(s"$cacheDir/${dotsToSlashes(name)}.dot")
+            IO.write(f, dot)
+            f
+        }.toSet
+        val cachedFun = FileFunction.cached(cacheDir, FileInfo.hash) { _ =>
+          val fs = Future.traverse(topologiesWithDots) {
+            case (topologyName, topology, _) =>
+              val svg = if (eisnerRoughSVG.value) topology.toSimplifiedRoughSVG(config) else topology.toSVG(config)
+              svg.map { svg =>
+                val filename = s"${eisnerTargetDirectory.value.getAbsolutePath}/${dotsToSlashes(topologyName)}.svg"
+                log.info(s"Eisner - saving $filename")
+                val f = new File(filename)
+                IO.write(f, svg)
+                f
+              }
+          }
+          Await.result(fs, 60.seconds).toSet
         }
-        Await.result(fs, 60.seconds)
+        cachedFun(inputs)
       } else {
         log.warn("Eisner - No topology found!")
-        Seq.empty
+        Set.empty
       }
     }
   }

src/main/scala/eisner/dot/dot.scala

@@ -17,21 +17,21 @@ package object dot {
     final def unapplySeq(s: String): Option[Seq[String]] = Some(s.split(',').flatMap(Clean.unapply).filter(_ != "none"))
   }
 
-  final def toDot(s: String): TopologyParserError | DiGraph = {
+  final def toDot(c: Config, s: String): TopologyParserError | DiGraph = {
     if (!s.startsWith("Topolog"))
       Left(TopologyParserError(s"Supplied string does not appear to be a valid topology (${s.substring(0, 10)}...)"))
     else {
       val (g, _) = s.split('\n').foldLeft(DiGraph.empty -> (None: Option[String])) {
         case ((DiGraph(sgs, es, ts, ss), maybeN), SubTopology(Clean(sc), id)) =>
-          DiGraph(SubGraph.empty(id, sc) :: sgs, es, ts, ss) -> maybeN
+          DiGraph(SubGraph.empty(id, sc, c.subgraphColor) :: sgs, es, ts, ss) -> maybeN
         case ((DiGraph(sgs, es, ts, ss), _), Source(Clean(n), Links(ls @ _*))) =>
-          DiGraph(sgs, es ++ ls.map(Edge(_, n)), ts ++ ls.map(Topic(_)), ss) -> Some(n)
+          DiGraph(sgs, es ++ ls.map(Edge(_, n)), ts ++ ls.map(Topic(_, c.topicColor)), ss) -> Some(n)
         case ((DiGraph(sgs, es, ts, ss), _), Processor(Clean(n), Links(ls @ _*))) =>
-          DiGraph(sgs, es ++ ls.map(Edge(n, _)), ts, ss ++ ls.map(Store(_))) -> Some(n)
+          DiGraph(sgs, es ++ ls.map(Edge(n, _)), ts, ss ++ ls.map(Store(_, c.storeColor))) -> Some(n)
         case ((DiGraph(sgs, es, ts, ss), _), Sink(Clean(n), Links(l))) =>
-          DiGraph(sgs, es :+ Edge(n, l), ts + Topic(l), ss) -> Some(n)
-        case ((DiGraph(SubGraph(id, la, sges) :: sgs, es, ts, ss), Some(n)), RightArrow(Links(ls @ _*))) =>
-          DiGraph(SubGraph(id, la, sges ++ ls.map(Edge(n, _))) :: sgs, es, ts, ss) -> Some(n)
+          DiGraph(sgs, es :+ Edge(n, l), ts + Topic(l, c.topicColor), ss) -> Some(n)
+        case ((DiGraph(SubGraph(id, la, sges, color) :: sgs, es, ts, ss), Some(n)), RightArrow(Links(ls @ _*))) =>
+          DiGraph(SubGraph(id, la, sges ++ ls.map(Edge(n, _)), color) :: sgs, es, ts, ss) -> Some(n)
         case (acc, _) =>
           acc
       }

src/main/scala/eisner/dot/model.scala

@@ -18,16 +18,16 @@ final object DiGraph {
   }
 }
 
-final case class SubGraph(id: String, label: String, edges: Vector[Edge])
+final case class SubGraph(id: String, label: String, edges: Vector[Edge], color: String)
 final object SubGraph {
-  final def empty(id: String, label: String): SubGraph = SubGraph(id, label, Vector.empty)
+  final def empty(id: String, label: String, color: String): SubGraph = SubGraph(id, label, Vector.empty, color)
 
   implicit final val subgraphWriter: Writer[SubGraph] = Writer.instance {
-    case (SubGraph(id, l, es), i) =>
+    case (SubGraph(id, l, es, c), i) =>
       s"${i.tabs}subgraph cluster_$id {" ::
         s"""${(i + 1).tabs}label = "$l";""" ::
         s"${(i + 1).tabs}style = filled;" ::
-        s"${(i + 1).tabs}color = lightgrey;" ::
+        s"${(i + 1).tabs}color = $c;" ::
         s"${(i + 1).tabs}node [style = filled, color = white];" ::
         Writer[Vector[Edge]].write(es, i + 1) :::
         s"${i.tabs}}" ::
@@ -40,12 +40,14 @@ final object Edge {
   implicit final val edgeWriter: Writer[Edge] = Writer.instance { case (Edge(f, t), i) => s"""${i.tabs}"$f" -> "$t";""" :: Nil }
 }
 
-final case class Topic(name: String) extends AnyVal
+final case class Topic(name: String, color: String)
 final object Topic {
-  implicit final val topicWriter: Writer[Topic] = Writer.instance { case (Topic(t), i) => s"""${i.tabs}"$t" [shape = rect];""" :: Nil }
+  implicit final val topicWriter: Writer[Topic] = Writer.instance { case (Topic(t, c), i) => s"""${i.tabs}"$t" [shape = rect; color = $c];""" :: Nil }
 }
 
-final case class Store(name: String) extends AnyVal
+final case class Store(name: String, color: String)
 final object Store {
-  implicit final val storeWriter: Writer[Store] = Writer.instance { case (Store(s), i) => s"""${i.tabs}"$s" [shape = cylinder];""" :: Nil }
+  implicit final val storeWriter: Writer[Store] = Writer.instance {
+    case (Store(s, c), i) => s"""${i.tabs}"$s" [shape = cylinder; color = $c];""" :: Nil
+  }
 }

src/main/scala/eisner/eisner.scala

@@ -9,25 +9,36 @@ package object eisner {
   private[eisner] final val Topic    = dot.Topic
   private[eisner] final val Store    = dot.Store
 
+  private[this] final val decimalsPattern = """\.(\d{2})\d+(\D?)""".r
+  private[this] object trimDoubles extends shapeless.poly.->((s: String) => decimalsPattern.replaceAllIn(s, ".$1$2"))
+  private[this] final def simplify(svg: SVG): SVG = {
+    val simplified = shapeless.everywhere(trimDoubles)(svg)
+    simplified
+  }
+
   implicit final class IntOps(private val i: Int) extends AnyVal {
     final def tabs: String = "\t" * i
   }
   implicit final class StringOps(private val s: String) extends AnyVal {
     import io.circe.parser.decode
     import scala.concurrent.{ExecutionContext, Future}
 
-    private[eisner] final def toDiGraph: TopologyParserError | DiGraph = dot.toDot(s)
-    private[eisner] final def decodeSVG: SVGParserError | SVG          = decode[SVG](s).left.map(e => SVGParserError(e.getLocalizedMessage()))
+    private[eisner] final def toDiGraph(c: Config): TopologyParserError | DiGraph = dot.toDot(c, s)
+    private[eisner] final def decodeSVG: SVGParserError | SVG                     = decode[SVG](s).left.map(e => SVGParserError(e.getLocalizedMessage()))
 
-    final def toDot: TopologyParserError | String = toDiGraph.map(_.dot)
-    final def toSVG(implicit ec: ExecutionContext): Future[String] = toDiGraph match {
+    final def toDot(c: Config): TopologyParserError | String = toDiGraph(c).map(_.dot)
+    final def toSVG(c: Config)(implicit ec: ExecutionContext): Future[String] = toDiGraph(c) match {
       case Left(tpe) => Future.failed(tpe)
       case Right(dg) => dg.simpleSVG.map(_.xml)
     }
-    final def toRoughSVG(implicit ec: ExecutionContext): Future[String] = toDiGraph match {
+    final def toRoughSVG(c: Config)(implicit ec: ExecutionContext): Future[String] = toDiGraph(c) match {
       case Left(tpe) => Future.failed(tpe)
       case Right(dg) => dg.simpleSVG.flatMap(_.roughSVG.fold(Future.failed, svg => Future.successful(svg.xml)))
     }
+    final def toSimplifiedRoughSVG(c: Config)(implicit ec: ExecutionContext): Future[String] = toDiGraph(c) match {
+      case Left(tpe) => Future.failed(tpe)
+      case Right(dg) => dg.simpleSVG.flatMap(_.roughSVG.fold(Future.failed, svg => Future.successful(svg.simplified.xml)))
+    }
   }
   private[eisner] implicit final class DiGraphOps(private val dg: DiGraph) extends AnyVal {
     import scala.concurrent.{ExecutionContext, Future}
@@ -40,6 +51,7 @@ package object eisner {
   private[eisner] implicit final class SVGOps(private val svg: SVG) extends AnyVal {
     import io.circe.Encoder
 
+    final def simplified: SVG                = simplify(svg)
     final def json: String                   = Encoder[SVG].apply(svg).noSpaces
     final def xml: String                    = Writer[SVG].write(svg, 0).mkString("\n")
     final def roughSVG: SVGParserError | SVG = js.svgToRoughSVG(json).decodeSVG

src/sbt-test/sbt-eisner/auto-field/test

@@ -1,4 +1,4 @@
 # invoke SVG creation
 > eisner
 # check that the SVG is created
-$ exists target/streams/_global/eisner/_global/streams/auto/field/InnerTopology#someField.svg
+$ exists target/eisner/auto/field/InnerTopology#someField.svg

src/sbt-test/sbt-eisner/auto-fun0field/test

@@ -1,4 +1,4 @@
 # invoke SVG creation
 > eisner
 # check that the SVG is created
-$ exists target/streams/_global/eisner/_global/streams/auto/fun0field/InnerTopology#someField.svg
+$ exists target/eisner/auto/fun0field/InnerTopology#someField.svg

src/sbt-test/sbt-eisner/auto-fun0method/test

@@ -1,4 +1,4 @@
 # invoke SVG creation
 > eisner
 # check that the SVG is created
-$ exists target/streams/_global/eisner/_global/streams/auto/fun0method/InnerTopology$someMethod.svg
+$ exists target/eisner/auto/fun0method/InnerTopology$someMethod.svg

src/sbt-test/sbt-eisner/auto-inheritance/test

@@ -1,4 +1,4 @@
 # invoke SVG creation
 > eisner
 # check that the SVG is created
-$ exists target/streams/_global/eisner/_global/streams/auto/inheritance/EisnerTopology.svg
+$ exists target/eisner/auto/inheritance/EisnerTopology.svg

src/sbt-test/sbt-eisner/auto-method/test

@@ -1,4 +1,4 @@
 # invoke SVG creation
 > eisner
 # check that the SVG is created
-$ exists target/streams/_global/eisner/_global/streams/auto/method/InnerTopology$someMethod.svg
+$ exists target/eisner/auto/method/InnerTopology$someMethod.svg

src/sbt-test/sbt-eisner/auto-supplierfield/test

@@ -1,4 +1,4 @@
 # invoke SVG creation
 > eisner
 # check that the SVG is created
-$ exists target/streams/_global/eisner/_global/streams/auto/supplierfield/InnerTopology#someField.svg
+$ exists target/eisner/auto/supplierfield/InnerTopology#someField.svg

src/sbt-test/sbt-eisner/auto-suppliermethod/test

@@ -1,4 +1,4 @@
 # invoke SVG creation
 > eisner
 # check that the SVG is created
-$ exists target/streams/_global/eisner/_global/streams/auto/suppliermethod/InnerTopology$someMethod.svg
+$ exists target/eisner/auto/suppliermethod/InnerTopology$someMethod.svg

src/sbt-test/sbt-eisner/empty/test

@@ -1,4 +1,4 @@
 # invoke SVG creation
 > eisner
 # check that the SVG is not created (topology is empty)
-$ absent target/streams/_global/eisner/_global/streams/EmptyTopology.svg
+$ absent target/eisner/EmptyTopology.svg

src/sbt-test/sbt-eisner/explicit-inheritance/test

@@ -1,4 +1,4 @@
 # invoke SVG creation
 > eisner
 # check that the SVG is created
-$ exists target/streams/_global/eisner/_global/streams/explicit/inheritance/EisnerTopology.svg
+$ exists target/eisner/explicit/inheritance/EisnerTopology.svg

src/sbt-test/sbt-eisner/snippet/test

@@ -1,4 +1,4 @@
 # invoke SVG creation
 > eisner
 # check that the SVG is created
-$ exists target/streams/_global/eisner/_global/streams/snippet/EisnerTopology#myTopology.svg
+$ exists target/eisner/snippet/EisnerTopology#myTopology.svg

src/test/resources/topology1.dot

@@ -25,9 +25,9 @@ digraph G {
 	"count-\nresolved-\nrepartition" -> "KSTREAM-\nSOURCE-\n0000000006";
 	"KSTREAM-\nAGGREGATE-\n0000000003" -> "count-\nresolved";
 	"KSTREAM-\nSINK-\n0000000008" -> "streams-\ncount-\nresolved";
-	"conversation-\nmeta" [shape = rect];
-	"count-\nresolved-\nrepartition" [shape = rect];
-	"streams-\ncount-\nresolved" [shape = rect];
-	"conversation-\nmeta-\nstate" [shape = cylinder];
-	"count-\nresolved" [shape = cylinder];
+	"conversation-\nmeta" [shape = rect; color = black];
+	"count-\nresolved-\nrepartition" [shape = rect; color = black];
+	"streams-\ncount-\nresolved" [shape = rect; color = black];
+	"conversation-\nmeta-\nstate" [shape = cylinder; color = black];
+	"count-\nresolved" [shape = cylinder; color = black];
 }

src/test/resources/topology2.dot

@@ -19,8 +19,8 @@ digraph G {
 	"KSTREAM-\nSINK-\n0000000004" -> "skus-\nwith-\ntaxcode";
 	"taxcodes" -> "KTABLE-\nSOURCE-\n0000000000";
 	"KTABLE-\nSOURCE-\n0000000001" -> "tax-\ncodes-\nstore";
-	"skus" [shape = rect];
-	"skus-\nwith-\ntaxcode" [shape = rect];
-	"taxcodes" [shape = rect];
-	"tax-\ncodes-\nstore" [shape = cylinder];
+	"skus" [shape = rect; color = black];
+	"skus-\nwith-\ntaxcode" [shape = rect; color = black];
+	"taxcodes" [shape = rect; color = black];
+	"tax-\ncodes-\nstore" [shape = cylinder; color = black];
 }

src/test/resources/topology3.dot

@@ -30,10 +30,10 @@ digraph G {
 	"KSTREAM-\nAGGREGATE-\n0000000010" -> "windowed-\ncount-\nstore";
 	"KSTREAM-\nSINK-\n0000000009" -> "count-\ntopic";
 	"KSTREAM-\nSINK-\n0000000017" -> "windowed-\ncount";
-	"streams-\nplaintext-\ninput" [shape = rect];
-	"count-\nstore-\nrepartition" [shape = rect];
-	"count-\ntopic" [shape = rect];
-	"windowed-\ncount" [shape = rect];
-	"count-\nstore" [shape = cylinder];
-	"windowed-\ncount-\nstore" [shape = cylinder];
+	"streams-\nplaintext-\ninput" [shape = rect; color = black];
+	"count-\nstore-\nrepartition" [shape = rect; color = black];
+	"count-\ntopic" [shape = rect; color = black];
+	"windowed-\ncount" [shape = rect; color = black];
+	"count-\nstore" [shape = cylinder; color = black];
+	"windowed-\ncount-\nstore" [shape = cylinder; color = black];
 }