update blockchain observer utilities

Author: arik-so

xcode/DirectBindingsApp/DirectBindingsApp/app-batteries/BlockchainObserver.swift

@@ -331,6 +331,13 @@ class BlockchainObserver {
         assert(blockHeader.count == 80)
         return blockHeader
     }
+    
+    public func getTransaction(hash: String) async throws -> [UInt8] {
+        let response = try await self.callRpcMethod(method: "getrawtransaction", params: [hash])
+        let txHex = response["result"] as! String
+        let transaction = hexStringToBytes(hexString: txHex)!
+        return transaction
+    }
 
     /**
      Get chain details such as the chaintip hash, the active soft forks, etc.
@@ -353,6 +360,21 @@ class BlockchainObserver {
         let result = response["result"] as! String
         return result
     }
+    
+    public func submitTransaction(transaction: [UInt8]) async throws -> String {
+        let txHex = bytesToHexString(bytes: transaction)
+        let response = try await self.callRpcMethod(method: "sendrawtransaction", params: [txHex])
+        // returns the txid
+        let result = response["result"] as! String
+        return result
+    }
+    
+    public func decodeScript(script: [UInt8]) async throws -> [String: Any] {
+        let scriptHex = bytesToHexString(bytes: script)
+        let response = try await self.callRpcMethod(method: "decodescript", params: [scriptHex])
+        let result = response["result"] as! [String: Any]
+        return result
+    }
 
 }
 

xcode/DirectBindingsApp/DirectBindingsAppTests/test-batteries/bitcoin/BitcoinTests.swift

@@ -114,10 +114,20 @@ public class BitcoinTests: XCTestCase {
         let genesisBinary = try await rpcInterface.getBlockBinary(hash: genesisHash)
         let genesisHeader = try await rpcInterface.getBlockHeader(hash: genesisHash)
 
+        let genesisCoinbaseTxHash = genesisDetails.tx.first!
+        let genesisCoinbaseTx = try await rpcInterface.getTransaction(hash: genesisCoinbaseTxHash)
+        
+        
+        // try? await rpcInterface.submitTransaction(transaction: modifiedCoinbaseTx)
+        
         // let address = try await rpcInterface.generateAddress()
         // let details = try await rpcInterface.mineBlocks(number: 1, coinbaseDestinationAddress: address)
         let helpDetails = try await rpcInterface.getHelp()
         print(helpDetails)
+        
+        let exampleFundingTx: [UInt8] = [1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 255, 255, 255, 255, 0, 255, 255, 255, 255, 1, 160, 134, 1, 0, 0, 0, 0, 0, 34, 0, 32, 15, 45, 153, 123, 98, 37, 242, 142, 113, 51, 126, 45, 206, 175, 66, 247, 173, 2, 141, 2, 27, 84, 38, 188, 34, 74, 82, 164, 28, 229, 39, 139, 1, 1, 1, 0, 0, 0, 0]
+        // try? await rpcInterface.submitTransaction(transaction: exampleFundingTx)
+        
 
         class Listener: BlockchainListener {
             var initializationComplete = false
@@ -143,7 +153,10 @@ public class BitcoinTests: XCTestCase {
         listener.initializationComplete = true
 
         let testAddress = try await rpcInterface.generateAddress()
-        try await rpcInterface.mineBlocks(number: 1, coinbaseDestinationAddress: testAddress)
+        let exampleOutputScript: [UInt8] = [0, 32, 200, 194, 75, 55, 227, 33, 251, 71, 196, 33, 177, 196, 155, 145, 17, 78, 244, 226, 155, 141, 216, 230, 180, 183, 149, 172, 116, 249, 56, 6, 118, 255]
+        let scriptInfo = try await rpcInterface.decodeScript(script: exampleOutputScript)
+        let outputAddress = (scriptInfo["addresses"] as! [String]).first!
+        try await rpcInterface.mineBlocks(number: 1, coinbaseDestinationAddress: outputAddress)
         // sleep for six seconds
         try await Task.sleep(nanoseconds: 6_000_000_000)
         XCTAssertEqual(listener.newBlockDetected, true)