Support parent field - closes #318

src/main/kotlin/org/ethereum/lists/chains/Env.kt

@@ -21,7 +21,8 @@ val optionalFields = listOf(
         "slip44",
         "ens",
         "icon",
-        "explorers"
+        "explorers",
+        "parent"
 )
 
 val moshi: Moshi = Moshi.Builder().add(KotlinJsonAdapterFactory()).build()

src/main/kotlin/org/ethereum/lists/chains/Main.kt

@@ -8,6 +8,7 @@ import org.ethereum.lists.chains.model.*
 import org.kethereum.erc55.isValid
 import org.kethereum.model.Address
 import org.kethereum.rpc.HttpEthereumRPC
+import java.lang.IllegalArgumentException
 
 val parsedShortNames = mutableSetOf<String>()
 val parsedNames = mutableSetOf<String>()
@@ -207,6 +208,25 @@ fun checkChain(chainFile: File, connectRPC: Boolean) {
         }
     }
 
+    jsonObject["parent"]?.let {
+        if (it !is JsonObject) {
+            throw ParentMustBeObject()
+        }
+
+        if (it.keys != mutableSetOf("chain", "type")) {
+            throw ParentMustHaveChainAndType()
+        }
+
+        if (!setOf("L2", "shard").contains(it["type"])) {
+            throw ParentHasInvalidType(it["type"] as? String)
+        }
+
+        if (!File(chainFile.parentFile, it["chain"] as String + ".json").exists()) {
+            throw ParentChainDoesNotExist(it["chain"] as String)
+        }
+
+    }
+
     if (connectRPC) {
         if (jsonObject["rpc"] is List<*>) {
             (jsonObject["rpc"] as List<*>).forEach {

src/main/kotlin/org/ethereum/lists/chains/model/Exceptions.kt

@@ -16,3 +16,7 @@ class ExplorersMustBeArray: Exception("explorers must be an array")
 class ExplorerMustHaveName: Exception("Explorer must have name")
 class ExplorerInvalidUrl: Exception("Explorer have url starting with https://")
 class ExplorerStandardMustBeEIP3091: Exception("explorer standard must be EIP3091 - currently the only one supported")
+class ParentHasInvalidType(type: String?): Exception("Parent has invalid type $type - only L2 or shard allowed")
+class ParentMustBeObject: Exception("parent must be an object")
+class ParentMustHaveChainAndType: Exception("parent must have fields 'chain' and 'type'")
+class ParentChainDoesNotExist(chain: String): Exception("Referenced parent chain ($chain) does not exist")

src/test/kotlin/org/ethereum/lists/chains/TheChainChecker.kt

@@ -28,6 +28,35 @@ class TheChainChecker {
         checkChain(file, false)
     }
 
+    @Test
+    fun shouldPassForValidChainWithParent() {
+        val file = getFile("valid/withparent/eip155-2.json")
+
+        checkChain(file, false)
+    }
+
+    @Test(expected = ParentMustBeObject::class)
+    fun shouldFailForParentNoObject() {
+        val file = getFile("invalid/withparentnobject/eip155-2.json")
+
+        checkChain(file, false)
+    }
+
+    @Test(expected = ParentHasInvalidType::class)
+    fun shouldFailForParentWithInvalidType() {
+        val file = getFile("invalid/withparentinvalidtype/eip155-2.json")
+
+        checkChain(file, false)
+    }
+
+
+    @Test(expected = ParentChainDoesNotExist::class)
+    fun shouldFailIfParentChainDoesNotExist() {
+        val file = getFile("invalid/withparentchaindoesnotexist/eip155-2.json")
+
+        checkChain(file, false)
+    }
+
     @Test(expected = FileNameMustMatchChainId::class)
     fun shouldFailForInvalidFilename() {
         val file = getFile("invalid/eip155-invalid_filename.json")

src/test/resources/test_chains/invalid/withparentchaindoesnotexist/eip155-2.json

@@ -0,0 +1,23 @@
+{
+  "name": "Ethereum Mainnet",
+  "shortName": "eth",
+  "chain": "ETH",
+  "network": "mainnet",
+  "chainId": 2,
+  "networkId": 2,
+  "rpc": [
+    "https://mainnet.infura.io/v3/${INFURA_API_KEY}",
+    "https://api.mycryptoapi.com/eth"
+  ],
+  "faucets": [],
+  "infoURL": "https://ethereum.org",
+  "nativeCurrency": {
+    "name": "Ether",
+    "symbol": "ETH",
+    "decimals": 18
+  },
+  "parent": {
+    "chain": "eip155-1",
+    "type": "L2"
+  }
+}

src/test/resources/test_chains/invalid/withparentinvalidtype/eip155-2.json

@@ -0,0 +1,23 @@
+{
+  "name": "Ethereum Mainnet",
+  "shortName": "eth",
+  "chain": "ETH",
+  "network": "mainnet",
+  "chainId": 2,
+  "networkId": 2,
+  "rpc": [
+    "https://mainnet.infura.io/v3/${INFURA_API_KEY}",
+    "https://api.mycryptoapi.com/eth"
+  ],
+  "faucets": [],
+  "infoURL": "https://ethereum.org",
+  "nativeCurrency": {
+    "name": "Ether",
+    "symbol": "ETH",
+    "decimals": 18
+  },
+  "parent": {
+    "chain": "eip155-1",
+    "type": "yolo"
+  }
+}

src/test/resources/test_chains/invalid/withparentnobject/eip155-2.json

@@ -0,0 +1,20 @@
+{
+  "name": "Ethereum Mainnet",
+  "shortName": "eth",
+  "chain": "ETH",
+  "network": "mainnet",
+  "chainId": 2,
+  "networkId": 2,
+  "rpc": [
+    "https://mainnet.infura.io/v3/${INFURA_API_KEY}",
+    "https://api.mycryptoapi.com/eth"
+  ],
+  "faucets": [],
+  "infoURL": "https://ethereum.org",
+  "nativeCurrency": {
+    "name": "Ether",
+    "symbol": "ETH",
+    "decimals": 18
+  },
+  "parent": "yolo"
+}

src/test/resources/test_chains/valid/withparent/eip155-1.json

@@ -0,0 +1,19 @@
+{
+  "name": "Ethereum Mainnet",
+  "shortName": "eth",
+  "chain": "ETH",
+  "network": "mainnet",
+  "chainId": 1,
+  "networkId": 1,
+  "rpc": [
+    "https://mainnet.infura.io/v3/${INFURA_API_KEY}",
+    "https://api.mycryptoapi.com/eth"
+  ],
+  "faucets": [],
+  "infoURL": "https://ethereum.org",
+  "nativeCurrency": {
+    "name": "Ether",
+    "symbol": "ETH",
+    "decimals": 18
+  }
+}

src/test/resources/test_chains/valid/withparent/eip155-2.json

@@ -0,0 +1,23 @@
+{
+  "name": "Ethereum Mainnet",
+  "shortName": "eth",
+  "chain": "ETH",
+  "network": "mainnet",
+  "chainId": 2,
+  "networkId": 2,
+  "rpc": [
+    "https://mainnet.infura.io/v3/${INFURA_API_KEY}",
+    "https://api.mycryptoapi.com/eth"
+  ],
+  "faucets": [],
+  "infoURL": "https://ethereum.org",
+  "nativeCurrency": {
+    "name": "Ether",
+    "symbol": "ETH",
+    "decimals": 18
+  },
+  "parent": {
+    "chain": "eip155-1",
+    "type": "L2"
+  }
+}