Fix jelly-text support in AOT builds (#131)

* Fix jelly-text support in AOT builds

Closes #128

Turns out that the Google proto classes require reflection for text serialization -- this was something that scalapb did not require.

To fix this, we could hardcode the methods and classes that need to have reflective access enabled, but it would be a mess to maintain. Instead, we have a custom Graal feature that discovers the needed classes and registers them for reflective access.

* fix typo

Author: Ostrzyciel

.github/workflows/aot-test.yml

@@ -35,7 +35,10 @@ jobs:
           target/graalvm-native-image/jelly-cli version && \
           echo '_:b <http://t.org/> _:b .' | target/graalvm-native-image/jelly-cli \
             rdf to-jelly --in-format=nt > out.jelly && \
-            [ -s out.jelly ]
+            [ -s out.jelly ] &&
+            target/graalvm-native-image/jelly-cli \
+            rdf from-jelly --out-format=jelly-text out.jelly > out.txt && \
+            [ -s out.txt ]
 
       - name: Upload binary
         uses: actions/upload-artifact@v4

build.sbt

@@ -7,6 +7,7 @@ resolvers +=
 
 lazy val jenaV = "5.3.0"
 lazy val jellyV = "3.1.0"
+lazy val graalvmV = "24.1.1"
 
 addCommandAlias("fixAll", "scalafixAll; scalafmtAll")
 
@@ -22,7 +23,9 @@ lazy val graalOptions = Seq(
   // Do a fast build if it's a dev build
   // For the release build, optimize for size and make a build report
   if (isDevBuild) Seq("-Ob") else Seq("-Os", "--emit build-report"),
-).flatten
+).flatten ++ Seq(
+  "--features=eu.neverblink.jelly.cli.graal.ProtobufFeature",
+)
 
 lazy val root = (project in file("."))
   .enablePlugins(
@@ -40,6 +43,9 @@ lazy val root = (project in file("."))
       "com.github.alexarchambault" %% "case-app" % "2.1.0-M30",
       "org.scalatest" %% "scalatest" % "3.2.19" % Test,
       "org.yaml" % "snakeyaml" % "2.4" % Test,
+      // For native-image reflection compatibility
+      "org.graalvm.sdk" % "graal-sdk" % graalvmV % "provided",
+      "org.reflections" % "reflections" % "0.10.2",
     ),
     scalacOptions ++= Seq(
       "-Wunused:imports",

src/main/scala/eu/neverblink/jelly/cli/graal/ProtobufFeature.scala

@@ -0,0 +1,25 @@
+package eu.neverblink.jelly.cli.graal
+
+import org.graalvm.nativeimage.hosted.{Feature, RuntimeReflection}
+import org.reflections.Reflections
+import org.reflections.scanners.Scanners
+
+import scala.jdk.CollectionConverters.*
+
+class ProtobufFeature extends Feature:
+  import Feature.*
+
+  override def getDescription: String =
+    "Registers Google-style Protobuf classes for reflection. Needed for jelly-text support."
+
+  override def beforeAnalysis(access: BeforeAnalysisAccess): Unit =
+    val reflections = Reflections("eu.neverblink.jelly.core.proto.google.v1", Scanners.SubTypes)
+    val classes = reflections.getSubTypesOf(
+      classOf[com.google.protobuf.GeneratedMessage],
+    ).asScala ++
+      reflections.getSubTypesOf(classOf[com.google.protobuf.GeneratedMessage.Builder[?]]).asScala ++
+      reflections.getSubTypesOf(classOf[com.google.protobuf.ProtocolMessageEnum]).asScala
+    classes.foreach(clazz => {
+      RuntimeReflection.register(clazz)
+      RuntimeReflection.register(clazz.getDeclaredMethods*)
+    })