slot height matcher implementation (#353)

src/main/kotlin/io/emeraldpay/dshackle/upstream/AbstractHead.kt

@@ -151,6 +151,10 @@ abstract class AbstractHead @JvmOverloads constructor(
         return getCurrent()?.height
     }
 
+    override fun getCurrentSlotHeight(): Long? {
+        return getCurrent()?.slot
+    }
+
     override fun stop() {
         stopping = true
         future?.let {

src/main/kotlin/io/emeraldpay/dshackle/upstream/EmptyHead.kt

@@ -31,6 +31,10 @@ class EmptyHead : Head {
     override fun getCurrentHeight(): Long? {
         return null
     }
+
+    override fun getCurrentSlotHeight(): Long? {
+        return null
+    }
     override fun start() {
     }
 

src/main/kotlin/io/emeraldpay/dshackle/upstream/Head.kt

@@ -38,6 +38,8 @@ interface Head {
 
     fun getCurrentHeight(): Long?
 
+    fun getCurrentSlotHeight(): Long?
+
     fun start()
 
     fun stop()

src/main/kotlin/io/emeraldpay/dshackle/upstream/MatchesResponse.kt

@@ -17,6 +17,7 @@ sealed class MatchesResponse {
             is ExistsResponse -> "Label ${this.name} does not exist"
             GrpcResponse -> "Upstream is not grpc"
             is HeightResponse -> "Upstream height ${this.currentHeight} is less than ${this.height}"
+            is SlotHeightResponse -> "Upstream slot height ${this.currentSlotHeight} is less than ${this.slot}"
             is MethodResponse -> "Method ${this.method} is not supported"
             is MultiResponse ->
                 this.allResponses
@@ -75,6 +76,11 @@ sealed class MatchesResponse {
         val currentHeight: Long,
     ) : MatchesResponse()
 
+    data class SlotHeightResponse(
+        val slot: Long,
+        val currentSlotHeight: Long,
+    ) : MatchesResponse()
+
     data class SameNodeResponse(
         val upstreamHash: Byte,
     ) : MatchesResponse()

src/main/kotlin/io/emeraldpay/dshackle/upstream/Selector.kt

@@ -25,6 +25,7 @@ import io.emeraldpay.dshackle.upstream.MatchesResponse.GrpcResponse
 import io.emeraldpay.dshackle.upstream.MatchesResponse.HeightResponse
 import io.emeraldpay.dshackle.upstream.MatchesResponse.NotMatchedResponse
 import io.emeraldpay.dshackle.upstream.MatchesResponse.SameNodeResponse
+import io.emeraldpay.dshackle.upstream.MatchesResponse.SlotHeightResponse
 import io.emeraldpay.dshackle.upstream.MatchesResponse.Success
 import org.apache.commons.lang3.StringUtils
 import java.util.Collections
@@ -44,6 +45,9 @@ class Selector {
             return selectors
                 .map {
                     when {
+                        it.hasSlotHeightSelector() -> {
+                            SlotMatcher(it.slotHeightSelector.slotHeight)
+                        }
                         it.hasHeightSelector() -> {
                             val height = if (it.heightSelector.height == -1L) head.getCurrentHeight() else it.heightSelector.height
                             if (height == null) {
@@ -488,6 +492,39 @@ class Selector {
         }
     }
 
+    class SlotMatcher(val slotHeight: Long) : Matcher() {
+
+        override fun matchesWithCause(up: Upstream): MatchesResponse {
+            val currentHeight = up.getHead().getCurrentSlotHeight() ?: 0
+            return if (currentHeight >= slotHeight) {
+                Success
+            } else {
+                SlotHeightResponse(slotHeight, currentHeight)
+            }
+        }
+
+        override fun equals(other: Any?): Boolean {
+            if (this === other) return true
+            if (other !is SlotMatcher) return false
+
+            if (slotHeight != other.slotHeight) return false
+
+            return true
+        }
+
+        override fun hashCode(): Int {
+            return slotHeight.hashCode()
+        }
+
+        override fun describeInternal(): String {
+            return "slot height $slotHeight"
+        }
+
+        override fun toString(): String {
+            return "Matcher: ${describeInternal()}"
+        }
+    }
+
     class SameNodeMatcher(private val upstreamHash: Byte) : Matcher() {
 
         override fun matchesWithCause(up: Upstream): MatchesResponse =

src/main/kotlin/io/emeraldpay/dshackle/upstream/ethereum/EnrichedMergedHead.kt

@@ -63,6 +63,10 @@ class EnrichedMergedHead constructor(
         return referenceHead.getCurrentHeight()
     }
 
+    override fun getCurrentSlotHeight(): Long? {
+        return referenceHead.getCurrentSlotHeight()
+    }
+
     override fun isRunning(): Boolean {
         return cacheSub != null
     }

src/test/groovy/io/emeraldpay/dshackle/test/EthereumHeadMock.groovy

@@ -68,6 +68,11 @@ class EthereumHeadMock implements Head {
         return latest?.height
     }
 
+    @Override
+    Long getCurrentSlotHeight() {
+        return latest?.slot
+    }
+
     @Override
     void start() {
 

src/test/groovy/io/emeraldpay/dshackle/upstream/FilteredApisSpec.groovy

@@ -462,7 +462,7 @@ class FilteredApisSpec extends Specification {
             _ * getRole() >> UpstreamsConfig.UpstreamRole.PRIMARY
             _ * isAvailable() >> true
             _ * getHead() >> Mock(Head) {
-                _ * getCurrentHeight() >> 100000001
+                _ * getCurrentSlotHeight() >> 100000001
             }
             _ * getStatus() >> UpstreamAvailability.OK
             _ * getLabels() >> of(UpstreamsConfig.Labels.fromMap(Map.of("node", "test")))
@@ -474,7 +474,7 @@ class FilteredApisSpec extends Specification {
                     _ * getId() >> "id1"
                     _ * getStatus() >> UpstreamAvailability.OK
                     _ * getHead() >> Mock(Head) {
-                        _ * getCurrentHeight() >> 100000
+                        _ * getCurrentSlotHeight() >> 100000
                     }
                     _ * getLabels() >> of(UpstreamsConfig.Labels.fromMap(Map.of("node", "archive")))
                 }, up
@@ -484,7 +484,7 @@ class FilteredApisSpec extends Specification {
                 Chain.ETHEREUM__MAINNET, ups,
                 new Selector.MultiMatcher(
                         of(
-                                new Selector.HeightMatcher(100000000),
+                                new Selector.SlotMatcher(100000000),
                                 new Selector.LabelMatcher("node", of("test"))
                         )
                 )

src/test/groovy/io/emeraldpay/dshackle/upstream/SelectorSpec.groovy

@@ -32,6 +32,21 @@ class SelectorSpec extends Specification {
     private BlockchainOuterClass.Selector selectLabel2Selector = BlockchainOuterClass.Selector.newBuilder()
             .setLabelSelector(selectLabel2).build()
 
+    def "Convert slot height selector"() {
+        setup:
+        def slotHeightSelector = BlockchainOuterClass.Selector.newBuilder()
+                .setSlotHeightSelector(
+                        BlockchainOuterClass.SlotHeightSelector.newBuilder()
+                                .setSlotHeight(10000)
+                                .build()
+                )
+                .build()
+        when:
+        def act = Selector.convertToMatcher(List.of(slotHeightSelector), Stub(Head))
+        then:
+        act == new Selector.MultiMatcher(List.of(new Selector.SlotMatcher(10000)))
+    }
+
     def "Convert height selector"() {
         setup:
         def heightSelector = BlockchainOuterClass.Selector.newBuilder()