solution: use existing caches to respond to full block request

src/test/groovy/io/emeraldpay/dshackle/cache/BlocksWithTxCacheSpec.groovy

@@ -0,0 +1,193 @@
+package io.emeraldpay.dshackle.cache
+
+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 spock.lang.Specification
+
+class BlocksWithTxCacheSpec extends Specification {
+
+    // sorted
+    String hash1 = "0x40d15edaff9acdabd2a1c96fd5f683b3300aad34e7015f34def3c56ba8a7ffb5"
+    String hash2 = "0x4aabdaff9acd2f30d15e00ab5dfd5f6c56ba4ea1c968a7ff8d3f34de70153b33"
+    String hash3 = "0xa4e7a75dfd5f6a83b3304dc56bfa0abfd3fef01540d15edafc9683f9acd2a13b"
+    String hash4 = "0xd3f34def3c56ba4e701540d15edaff9acd2a1c968a7ff83b3300ab5dfd5f6aab"
+
+    def tx1 = new TransactionJson().with {
+        it.blockNumber = 100
+        it.blockHash = BlockHash.from(hash1)
+        it.hash = TransactionId.from(hash1)
+        it.nonce = 1
+        it
+    }
+    def tx2 = new TransactionJson().with {
+        it.blockNumber = 100
+        it.blockHash = BlockHash.from(hash1)
+        it.hash = TransactionId.from(hash2)
+        it.nonce = 2
+        it
+    }
+    def tx3 = new TransactionJson().with {
+        it.blockNumber = 101
+        it.blockHash = BlockHash.from(hash3)
+        it.hash = TransactionId.from(hash3)
+        it.nonce = 3
+        it
+    }
+
+    // no block
+    def tx4 = new TransactionJson().with {
+        it.blockNumber = 102
+        it.blockHash = BlockHash.from(hash4)
+        it.hash = TransactionId.from(hash4)
+        it.nonce = 4
+        it
+    }
+
+    // two transactiosn, tx1 and tx2
+    def block1 = new BlockJson().with {
+        it.number = 100
+        it.hash = BlockHash.from(hash1)
+        it.transactions = [
+                new TransactionRefJson(tx1.hash),
+                new TransactionRefJson(tx2.hash)
+        ]
+        it
+    }
+
+    // one transaction, tx3
+    def block2 = new BlockJson().with {
+        it.number = 101
+        it.hash = BlockHash.from(hash3)
+        it.transactions = [
+                new TransactionRefJson(tx3.hash)
+        ]
+        it
+    }
+
+    // no transactions
+    def block3 = new BlockJson().with {
+        it.number = 102
+        it.hash = BlockHash.from(hash4)
+        it.transactions = []
+        it
+    }
+
+
+    def "Read transactions and return full block"() {
+        setup:
+        def txes = new TxMemCache()
+        def blocks = new BlocksMemCache()
+
+        txes.add(tx1)
+        txes.add(tx2)
+        txes.add(tx3)
+        txes.add(tx4)
+        blocks.add(block1)
+        blocks.add(block2)
+        blocks.add(block3)
+
+        def full = new BlocksWithTxCache(blocks, txes)
+
+        when:
+        def act = full.read(block1.hash).block()
+
+        then:
+        act != null
+        act.hash == BlockHash.from(hash1)
+        act.number == 100
+        act.transactions.size() == 2
+
+        when:
+        def transactions = act.transactions.sort { it.hash }
+        then:
+        transactions[0] instanceof TransactionJson
+        transactions[1] instanceof TransactionJson
+        //verify it didn't update original block
+        block1.transactions[0] instanceof TransactionRefJson
+        block1.transactions[1] instanceof TransactionRefJson
+        with(transactions[0]) {
+            hash == TransactionId.from(hash1)
+            nonce == 1
+        }
+        with(transactions[1]) {
+            hash == TransactionId.from(hash2)
+            nonce == 2
+        }
+
+        // request second block
+        when:
+        act = full.read(block2.hash).block()
+        then:
+        act != null
+        act.hash == BlockHash.from(hash3)
+        act.number == 101
+        act.transactions.size() == 1
+        with(act.transactions[0]) {
+            hash == TransactionId.from(hash3)
+            nonce == 3
+        }
+    }
+
+    def "Read block without transactions"() {
+        setup:
+        def txes = new TxMemCache()
+        def blocks = new BlocksMemCache()
+
+        txes.add(tx1)
+        txes.add(tx2)
+        txes.add(tx3)
+        txes.add(tx4)
+        blocks.add(block1)
+        blocks.add(block2)
+        blocks.add(block3)
+
+        def full = new BlocksWithTxCache(blocks, txes)
+
+        when:
+        def act = full.read(block3.hash).block()
+
+        then:
+        act != null
+        act.hash == BlockHash.from(hash4)
+        act.number == 102
+        act.transactions.size() == 0
+    }
+
+    def "Return nothing if no transactions"() {
+        setup:
+        def txes = new TxMemCache()
+        def blocks = new BlocksMemCache()
+
+        txes.add(tx1)
+        blocks.add(block1) //missing tx2 in cache
+
+        def full = new BlocksWithTxCache(blocks, txes)
+
+        when:
+        def act = full.read(block1.hash).block()
+
+        then:
+        act == null
+    }
+
+    def "Return nothing if no block"() {
+        setup:
+        def txes = new TxMemCache()
+        def blocks = new BlocksMemCache()
+
+        txes.add(tx1)
+        txes.add(tx2)
+        txes.add(tx3)
+
+        def full = new BlocksWithTxCache(blocks, txes)
+
+        when:
+        def act = full.read(block1.hash).block()
+
+        then:
+        act == null
+    }
+}

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

@@ -4,6 +4,7 @@ import io.emeraldpay.dshackle.cache.BlockByHeight
 import io.emeraldpay.dshackle.cache.BlocksMemCache
 import io.emeraldpay.dshackle.cache.Caches
 import io.emeraldpay.dshackle.cache.HeightCache
+import io.emeraldpay.dshackle.cache.TxMemCache
 import io.emeraldpay.dshackle.reader.EmptyReader
 import io.emeraldpay.dshackle.test.TestingCommons
 import io.emeraldpay.dshackle.upstream.ethereum.EthereumHead
@@ -12,6 +13,7 @@ import io.infinitape.etherjar.domain.TransactionId
 import io.infinitape.etherjar.rpc.json.BlockJson
 import io.infinitape.etherjar.rpc.json.TransactionRefJson
 import reactor.core.publisher.Flux
+import reactor.core.publisher.Mono
 import reactor.test.StepVerifier
 import spock.lang.Specification
 
@@ -100,4 +102,97 @@ class CachingEthereumApiSpec extends Specification {
                 .verify(Duration.ofSeconds(3))
     }
 
+    def "Uses base cache when requested, by hash"() {
+        setup:
+        def blocksCache = Mock(BlocksMemCache)
+        def txCache = Mock(TxMemCache)
+        def head = Mock(EthereumHead.class)
+        def api = new CachingEthereumApi(
+                TestingCommons.objectMapper(),
+                Caches.newBuilder().setBlockByHash(blocksCache).setTxByHash(txCache).build(),
+                head
+        )
+        def block = new BlockJson<TransactionRefJson>(number: 100, hash: BlockHash.from("0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58"))
+
+        when:
+        def act = api.readBlockByHash(1, "eth_getBlockByHash", ["0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58", false]).block()
+
+        then:
+        act != null
+        1 * blocksCache.read(BlockHash.from("0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58")) >> Mono.just(block)
+        0 * txCache.read(_)
+    }
+
+    def "Uses full cache when requested, by hash"() {
+        setup:
+        def blocksCache = Mock(BlocksMemCache)
+        def txCache = Mock(TxMemCache)
+        def head = Mock(EthereumHead.class)
+        def api = new CachingEthereumApi(
+                TestingCommons.objectMapper(),
+                Caches.newBuilder().setBlockByHash(blocksCache).setTxByHash(txCache).build(),
+                head
+        )
+        def block = new BlockJson<TransactionRefJson>(number: 100, hash: BlockHash.from("0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58"))
+        block.transactions = [
+                new TransactionRefJson(TransactionId.from("0x0500219f2b147f3013e9030d585e8e5d45401ebd2620a42c879c0d5d1b754073"))
+        ]
+
+        when:
+        def act = api.readBlockByHash(1, "eth_getBlockByHash", ["0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58", true]).block()
+
+        then:
+        act == null
+        1 * blocksCache.read(BlockHash.from("0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58")) >> Mono.just(block)
+        1 * txCache.read(TransactionId.from("0x0500219f2b147f3013e9030d585e8e5d45401ebd2620a42c879c0d5d1b754073")) >> Mono.empty()
+    }
+
+    def "Uses base cache when requested, by height"() {
+        setup:
+        def blocksCache = Mock(BlocksMemCache)
+        def txCache = Mock(TxMemCache)
+        def heightCache = Mock(HeightCache)
+        def head = Mock(EthereumHead.class)
+        def api = new CachingEthereumApi(
+                TestingCommons.objectMapper(),
+                Caches.newBuilder().setBlockByHash(blocksCache).setTxByHash(txCache).setBlockByHeight(heightCache).build(),
+                head
+        )
+        def block = new BlockJson<TransactionRefJson>(number: 100, hash: BlockHash.from("0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58"))
+
+        when:
+        def act = api.readBlockByNumber(1, "eth_getBlockByNumber", ["0x64", false]).block()
+
+        then:
+        act != null
+        1 * heightCache.read(100) >> Mono.just(BlockHash.from("0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58"))
+        1 * blocksCache.read(BlockHash.from("0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58")) >> Mono.just(block)
+        0 * txCache.read(_)
+    }
+
+    def "Uses full cache when requested, by height"() {
+        setup:
+        def blocksCache = Mock(BlocksMemCache)
+        def txCache = Mock(TxMemCache)
+        def heightCache = Mock(HeightCache)
+        def head = Mock(EthereumHead.class)
+        def api = new CachingEthereumApi(
+                TestingCommons.objectMapper(),
+                Caches.newBuilder().setBlockByHash(blocksCache).setTxByHash(txCache).setBlockByHeight(heightCache).build(),
+                head
+        )
+        def block = new BlockJson<TransactionRefJson>(number: 100, hash: BlockHash.from("0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58"))
+        block.transactions = [
+                new TransactionRefJson(TransactionId.from("0x0500219f2b147f3013e9030d585e8e5d45401ebd2620a42c879c0d5d1b754073"))
+        ]
+
+        when:
+        def act = api.readBlockByNumber(1, "eth_getBlockByNumber", ["0x64", true]).block()
+
+        then:
+        act == null
+        1 * heightCache.read(100) >> Mono.just(BlockHash.from("0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58"))
+        1 * blocksCache.read(BlockHash.from("0x5b4590a9905fa1c9cc273f32e6dc63b4c512f0ee14edc6fa41c26b416a7b5d58")) >> Mono.just(block)
+        1 * txCache.read(TransactionId.from("0x0500219f2b147f3013e9030d585e8e5d45401ebd2620a42c879c0d5d1b754073")) >> Mono.empty()
+    }
 }