problem: full block returns transactions in different order

fix: #82

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

@@ -70,7 +70,7 @@ class EthereumFullBlocksReader(
             val blockSplit = splitByTransactions(block.json!!)
 
             val transactions = Flux.fromIterable(block.transactions)
-                    .flatMap { txes.read(it) }
+                    .flatMapSequential { txes.read(it) }
                     .collectList()
 
             return@flatMap transactions.flatMap { transactionsData ->

src/test/groovy/io/emeraldpay/dshackle/upstream/ethereum/EthereumFullBlocksReaderSpec.groovy

@@ -23,16 +23,19 @@ import io.emeraldpay.dshackle.cache.TxMemCache
 import io.emeraldpay.dshackle.data.BlockContainer
 import io.emeraldpay.dshackle.data.BlockId
 import io.emeraldpay.dshackle.data.TxContainer
+import io.emeraldpay.dshackle.data.TxId
 import io.emeraldpay.dshackle.reader.Reader
 import io.infinitape.etherjar.domain.BlockHash
 import io.infinitape.etherjar.domain.TransactionId
 import io.infinitape.etherjar.rpc.json.BlockJson
 import io.infinitape.etherjar.rpc.json.TransactionJson
 import io.infinitape.etherjar.rpc.json.TransactionRefJson
 import org.apache.commons.codec.binary.Hex
+import reactor.core.publisher.Mono
 import spock.lang.Specification
 
 import java.nio.ByteBuffer
+import java.time.Duration
 import java.time.Instant
 
 class EthereumFullBlocksReaderSpec extends Specification {
@@ -111,6 +114,21 @@ class EthereumFullBlocksReaderSpec extends Specification {
         it
     }
 
+    // all transaction2
+    def block4 = new BlockJson().with {
+        it.number = 103
+        it.hash = BlockHash.from(hash3)
+        it.totalDifficulty = BigInteger.ONE
+        it.timestamp = Instant.now()
+        it.transactions = [
+                new TransactionRefJson(tx1.hash),
+                new TransactionRefJson(tx2.hash),
+                new TransactionRefJson(tx3.hash),
+                new TransactionRefJson(tx4.hash)
+        ]
+        it
+    }
+
 
     def "Read transactions and return full block"() {
         setup:
@@ -178,6 +196,34 @@ class EthereumFullBlocksReaderSpec extends Specification {
         }
     }
 
+    def "Produce block with original order of transactions"() {
+        setup:
+        def txes = Mock(Reader) {
+            1 * it.read(TxId.from(tx1.hash)) >> Mono.just(TxContainer.from(tx1)).delayElement(Duration.ofMillis(50))
+            1 * it.read(TxId.from(tx2.hash)) >> Mono.just(TxContainer.from(tx2)).delayElement(Duration.ofMillis(40))
+            1 * it.read(TxId.from(tx3.hash)) >> Mono.just(TxContainer.from(tx3)).delayElement(Duration.ofMillis(30))
+            1 * it.read(TxId.from(tx4.hash)) >> Mono.just(TxContainer.from(tx4)).delayElement(Duration.ofMillis(20))
+        }
+        def blocks = new BlocksMemCache()
+        blocks.add(BlockContainer.from(block4))
+
+        def full = new EthereumFullBlocksReader(blocks, txes)
+
+        when:
+        def act = full.read(BlockId.from(block4.hash)).block()
+        act = objectMapper.readValue(act.json, BlockJson)
+        def transactions = act.transactions
+
+        then:
+        transactions.size() == 4
+        transactions[0] instanceof TransactionJson
+        transactions[1] instanceof TransactionJson
+        transactions[0].hash == TransactionId.from(hash1)
+        transactions[1].hash == TransactionId.from(hash2)
+        transactions[2].hash == TransactionId.from(hash3)
+        transactions[3].hash == TransactionId.from(hash4)
+    }
+
     def "Read block without transactions"() {
         setup:
         def txes = new TxMemCache()

testing/dshackle/README.adoc

@@ -3,5 +3,12 @@
 .Run from project root directory:
 [source,bash]
 ----
-./gradlew run --args="--configPath=./testing/dshackle/dshackle.yaml"
+./gradlew run --args="--configPath=./testing/dshackle/dshackle-mock.yaml"
+----
+
+or
+
+[source,bash]
+----
+./gradlew run --args="--configPath=./testing/dshackle/dshackle-real.yaml"
 ----

testing/dshackle/dshackle-real.yaml

@@ -0,0 +1,29 @@
+version: v1
+port: 12448
+
+tls:
+  enabled: false
+
+cluster:
+  upstreams:
+    - id: eth-1
+      chain: ethereum
+      connection:
+        ethereum:
+          rpc:
+            url: "${DSHACKLE_TEST_ETH1_RPC}"
+          ws:
+            url: "${DSHACKLE_TEST_ETH1_WS}"
+            origin: "${DSHACKLE_TEST_ETH1_WSORIGIN}"
+
+cache:
+  redis:
+    enabled: false
+
+proxy:
+  port: 18081
+  tls:
+    enabled: false
+  routes:
+    - id: eth
+      blockchain: ethereum

testing/trial/src/main/groovy/io/emeraldpay/dshackle/testing/trial/ProxyClient.groovy

@@ -24,8 +24,20 @@ class ProxyClient {
         this.objectMapper = new ObjectMapper()
     }
 
+    static ProxyClient ethereumMock() {
+        return forPrefix(18080, "eth")
+    }
+
+    static ProxyClient ethereumReal() {
+        return forPrefix(18081, "eth")
+    }
+
     static ProxyClient forPrefix(String prefix) {
-        return new ProxyClient("http://127.0.0.1:18080/$prefix")
+        return forPrefix(18080, prefix)
+    }
+
+    static ProxyClient forPrefix(int port, String prefix) {
+        return new ProxyClient("http://127.0.0.1:$port/$prefix")
     }
 
     static ProxyClient forOriginal(int port) {

testing/trial/src/test/groovy/io/emeraldpay/dshackle/testing/trial/proxy/GetBlockRealSpec.groovy

@@ -0,0 +1,38 @@
+package io.emeraldpay.dshackle.testing.trial.proxy
+
+import io.emeraldpay.dshackle.testing.trial.Debugger
+import io.emeraldpay.dshackle.testing.trial.ProxyClient
+import spock.lang.Specification
+import spock.lang.Timeout
+
+class GetBlockRealSpec extends Specification {
+
+    def client = ProxyClient.ethereumReal()
+
+    def setup() {
+        Debugger.enabled = false
+    }
+
+    def cleanup() {
+        Debugger.enabled = true
+    }
+
+    @Timeout(15)
+    def "Correct order for transactions on #height"() {
+        expect:
+        def results = [
+                (client.execute("eth_getBlockByNumber", ["0x" + Integer.toString(height, 16), false]).result["transactions"] as List<String>),
+                (client.execute("eth_getBlockByNumber", ["0x" + Integer.toString(height, 16), true]).result["transactions"] as List<Map<String, Object>>)
+                        .collect { it.hash }
+        ]
+
+        println(results[0])
+        println(results[1])
+
+        results[0] == results[1]
+
+        where:
+        height << (10_000_000..10_000_500)
+
+    }
+}