support embedding GDALMetadata with tiffset #317

openeo-geotrellis/src/main/scala/org/openeo/geotrellis/geotiff/package.scala

@@ -922,4 +922,24 @@ package object geotiff {
     result.collect()
     print("test done")
   }
+
+  // TODO: favor dedicated XML type over String?
+  def embedGdalMetadata(gdalMetadataXml: String, geotiffPath: Path): Unit = {
+    import scala.sys.process._
+    import java.nio.charset._
+
+    val outputBuffer = new StringBuilder
+    val processLogger = ProcessLogger(line => outputBuffer appendAll line)
+
+    val tempFile = Files.createTempFile("GDALMetadata_", ".xml.tmp")
+    try {
+      Files.write(tempFile, s"$gdalMetadataXml\n".getBytes(StandardCharsets.US_ASCII))
+
+      val args = Seq("tiffset", "-sf", "42112", tempFile.toString, geotiffPath.toString)
+      val exitCode = args ! processLogger
+      if (exitCode != 0) {
+        throw new Exception(s"${args mkString " "} failed; output: $outputBuffer")
+      }
+    } finally Files.delete(tempFile)
+  }
 }

openeo-geotrellis/src/test/scala/org/openeo/geotrellis/geotiff/PackageTest.scala

@@ -0,0 +1,40 @@
+package org.openeo.geotrellis.geotiff
+
+import geotrellis.raster.io.geotiff.MultibandGeoTiff
+import org.junit.jupiter.api.Assertions.{assertEquals, assertThrows, assertTrue}
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.io.TempDir
+
+import java.nio.file.{Files, Path, Paths}
+
+class PackageTest {
+
+  @Test
+  def testEmbedGdalMetadata(@TempDir tempDir: Path): Unit = {
+    val geotiffCopy = tempDir.resolve("copy.tif")
+    Files.copy(getClass.getResourceAsStream("/org/openeo/geotrellis/cgls_ndvi300.tif"), geotiffCopy)
+
+    assertTrue(processingSoftware(geotiffCopy).isEmpty)
+
+    val gdalMetadataXml =
+      <GDALMetadata>
+        <Item name="PROCESSING_SOFTWARE">0.45.0a1</Item>
+        <Item name="DESCRIPTION" sample="0">CO</Item>
+      </GDALMetadata>
+
+    embedGdalMetadata(gdalMetadataXml.toString(), geotiffCopy)
+
+    assertEquals(Some("0.45.0a1"), processingSoftware(geotiffCopy))
+  }
+
+  @Test
+  def testEmbedGdalMetadataFails(): Unit = {
+    val e = assertThrows(classOf[Exception], () =>
+      embedGdalMetadata(gdalMetadataXml = "", geotiffPath = Paths.get("doesnotexist.tif")))
+
+    assertTrue(e.getMessage contains "doesnotexist.tif: No such file or directory")
+  }
+
+  private def processingSoftware(geotiff: Path): Option[String] =
+    MultibandGeoTiff(geotiff.toString).tags.headTags.get("PROCESSING_SOFTWARE")
+}