support construction of GDALMetadata #317

Open-EO · Oct 25, 2024 · 4c4275e · 4c4275e
1 parent 4f1ede1
commit 4c4275e
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Showing 2 changed files with 48 additions and 3 deletions.
diff --git a/openeo-geotrellis/src/main/scala/org/openeo/geotrellis/geotiff/GTiffOptions.scala b/openeo-geotrellis/src/main/scala/org/openeo/geotrellis/geotiff/GTiffOptions.scala
@@ -15,6 +15,8 @@ class GTiffOptions extends Serializable {
   var resampleMethod:String = "near"
   var separateAssetPerBand = false
 
+  private val xmlTags = collection.mutable.Buffer[String]() // TODO: improve
+
   def setFilenamePrefix(name: String): Unit = this.filenamePrefix = name
 
   def setSeparateAssetPerBand(value: Boolean): Unit = this.separateAssetPerBand = value
@@ -47,20 +49,42 @@ class GTiffOptions extends Serializable {
     })
   }
 
-  def addHeadTag(tagName:String,value:String): Unit = {
+  def addHeadTag(tagName:String, value:String): Unit = {
     tags = Tags(tags.headTags + (tagName -> value), tags.bandTags)
+
+    xmlTags append asItemElement(tagName, value)
   }
 
-  def addBandTag(bandIndex:Int, tagName:String,value:String): Unit = {
+  def addBandTag(bandIndex: Int, tagName:String, value:String, role: Option[String]): Unit = {
     val emptyMap = Map.empty[String, String]
     var newBandTags = Vector.fill[Map[String,String]](math.max(bandIndex+1,tags.bandTags.size))(emptyMap)
     newBandTags =  newBandTags.zipAll(tags.bandTags,emptyMap,emptyMap).map(elem => elem._1 ++ elem._2)
     newBandTags = newBandTags.updated(bandIndex, newBandTags(bandIndex) + (tagName -> value))
     tags = Tags(tags.headTags ,newBandTags.toList)
+
+    xmlTags append asItemElement(tagName, value, Some(bandIndex), role)
   }
 
+  def addBandTag(bandIndex: Int, tagName: String, value: String): Unit =
+    addBandTag(bandIndex, tagName, value, role = None)
+
   def setBandTags(newBandTags: List[Map[String, String]]): Unit = {
     tags = Tags(tags.headTags, newBandTags)
+
+    xmlTags.clear()
+    for ((tagName, value) <- tags.headTags) addHeadTag(tagName, value)
+    for {
+      (band, bandIndex) <- newBandTags.zipWithIndex
+      (tagName, value) <- band
+    } addBandTag(bandIndex, tagName, value)
+  }
+
+  def toGdalMetadataXml: String = {
+    val buffer = new StringBuilder("<GDALMetadata>")
+    for (xmlTag <- xmlTags) buffer.appendAll(xmlTag)
+    buffer.appendAll("</GDALMetadata>")
+
+    buffer.toString
   }
 
   /**
@@ -78,4 +102,11 @@ class GTiffOptions extends Serializable {
     val ois = new java.io.ObjectInputStream(bais)
     ois.readObject().asInstanceOf[GTiffOptions]
   }
+
+  private def asItemElement(name: String, value: Any, index: Option[Int] = None,
+                            role: Option[String] = None): String = {
+    val sampleAttribute = index.map(i => s"""sample="$i"""").getOrElse("")
+    val roleAttribute = role.map(r => s"""role="$r"""").getOrElse("")
+    s"""<Item name="$name" $sampleAttribute $roleAttribute>$value</Item>"""
+  }
 }
diff --git a/openeo-geotrellis/src/test/scala/org/openeo/geotrellis/geotiff/GTiffOptionsTest.scala b/openeo-geotrellis/src/test/scala/org/openeo/geotrellis/geotiff/GTiffOptionsTest.scala
@@ -3,6 +3,9 @@ package org.openeo.geotrellis.geotiff
 import org.junit.Assert.assertEquals
 import org.junit.Test
 
+import scala.xml.XML
+import scala.xml.Utility.trim
+
 class GTiffOptionsTest {
 
   @Test
@@ -13,7 +16,7 @@ class GTiffOptionsTest {
     val bandNames = Seq("VV", "VH", "mask", "local_incidence_angle")
 
     for ((bandName, index) <- bandNames.zipWithIndex) {
-      options.addBandTag(index, "DESCRIPTION", bandName)
+      options.addBandTag(index, "DESCRIPTION", bandName, role = Some("description"))
     }
 
     assertEquals(Map("PROCESSING_SOFTWARE" -> "0.6.1a1"), options.tags.headTags)
@@ -23,5 +26,16 @@ class GTiffOptionsTest {
       Map("DESCRIPTION" -> "mask"),
       Map("DESCRIPTION" -> "local_incidence_angle")
     ), options.tags.bandTags)
+
+    val expectedGdalMetadataXml =
+      <GDALMetadata>
+        <Item name="PROCESSING_SOFTWARE">0.6.1a1</Item>
+        <Item name="DESCRIPTION" sample="0" role="description">VV</Item>
+        <Item name="DESCRIPTION" sample="1" role="description">VH</Item>
+        <Item name="DESCRIPTION" sample="2" role="description">mask</Item>
+        <Item name="DESCRIPTION" sample="3" role="description">local_incidence_angle</Item>
+      </GDALMetadata>
+
+    assertEquals(trim(expectedGdalMetadataXml), trim(XML.loadString(options.toGdalMetadataXml)))
   }
 }