Corda: CommitSubFlow

- remove GameProposalResolution state
use ladger trx history instead

- use issuer/acquier instead of sennder/receiver

backend/src/main/java/djmil/cordacheckers/cordaclient/CordaClient.java

@@ -14,17 +14,23 @@ import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Service;
 import org.springframework.web.client.RestTemplate;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonMappingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 
 import djmil.cordacheckers.cordaclient.dao.HoldingIdentity;
 import djmil.cordacheckers.cordaclient.dao.Color;
+import djmil.cordacheckers.cordaclient.dao.GameProposal;
 import djmil.cordacheckers.cordaclient.dao.VirtualNode;
 import djmil.cordacheckers.cordaclient.dao.VirtualNodeList;
 import djmil.cordacheckers.cordaclient.dao.flow.RequestBody;
 import djmil.cordacheckers.cordaclient.dao.flow.ResponseBody;
-import djmil.cordacheckers.cordaclient.dao.flow.arguments.CreateGameProposal;
+import djmil.cordacheckers.cordaclient.dao.flow.arguments.GameProposalCreateReq;
+import djmil.cordacheckers.cordaclient.dao.flow.arguments.GameProposalCreateRes;
+import djmil.cordacheckers.cordaclient.dao.flow.arguments.GameProposalListRes;
 import djmil.cordacheckers.cordaclient.dao.flow.arguments.Empty;
-import djmil.cordacheckers.cordaclient.dao.flow.arguments.GameProposalAction;
+import djmil.cordacheckers.cordaclient.dao.flow.arguments.GameProposalActionReq;
+import djmil.cordacheckers.cordaclient.dao.flow.arguments.GameProposalActionRes;
 
 @Service
 public class CordaClient {
@@ -59,7 +65,7 @@ public class CordaClient {
      * @param holdingIdentity
      * @return GameProposals list in JSON form
      */
-    public String listGameProposals(HoldingIdentity holdingIdentity) {
+    public List<GameProposal> gameProposalList(HoldingIdentity holdingIdentity) {
 
         final RequestBody requestBody = new RequestBody(
             "list-" + UUID.randomUUID(),
@@ -67,21 +73,27 @@ public class CordaClient {
             new Empty()
             );
 
-        final String gameProposalsJsonString = cordaFlowExecute(
+        final GameProposalListRes listFlowResult = cordaFlowExecute(
             holdingIdentity,
-            requestBody
+            requestBody,
+            GameProposalListRes.class
             );
 
-        return gameProposalsJsonString;
+        if (listFlowResult.failureStatus() != null) {
+            System.out.println("GameProposalCreateFlow failed: " + listFlowResult.failureStatus());
+            throw new RuntimeException("GameProsal: CreateFlow execution has failed");
+        }
+
+        return listFlowResult.successStatus();
     }
 
-    public String createGameProposal(
+    public UUID gameProposalCreate(
         HoldingIdentity sender,
         HoldingIdentity receiver,
         Color receiverColor,
         String message
-    ) {
-        final CreateGameProposal createGameProposal = new CreateGameProposal(
+    ) throws JsonMappingException, JsonProcessingException {
+        final GameProposalCreateReq createGameProposal = new GameProposalCreateReq(
             receiver.x500Name(),
             receiverColor,
             message
@@ -93,21 +105,28 @@ public class CordaClient {
             createGameProposal
             );
 
-        final String createdGameProposalUuid = cordaFlowExecute(
+        final GameProposalCreateRes createResult = cordaFlowExecute(
             sender,
-            requestBody
+            requestBody,
+            GameProposalCreateRes.class
             );
 
-        return createdGameProposalUuid;
+        if (createResult.failureStatus() != null) {
+            System.out.println("GameProposalCreateFlow failed: " + createResult.failureStatus());
+            throw new RuntimeException("GameProsal: CreateFlow execution has failed");
+        }
+
+        return createResult.successStatus();
     }
 
-    public String rejectGameProposal(
+    public String gameProposalAction(
         HoldingIdentity self,
-        String gameProposalUuid
+        UUID gameProposalUuid,
+        GameProposalActionReq.Action action
     ) {
-        final GameProposalAction rejectGameProposal = new GameProposalAction(
-            gameProposalUuid,
-            GameProposalAction.Action.REJECT
+        final GameProposalActionReq rejectGameProposal = new GameProposalActionReq(
+            gameProposalUuid.toString(),
+            action
             );
 
         final RequestBody requestBody = new RequestBody(
@@ -116,15 +135,21 @@ public class CordaClient {
             rejectGameProposal
             );
 
-        final String createdGameProposalUuid = cordaFlowExecute(
+        final GameProposalActionRes actionResult = cordaFlowExecute(
             self,
-            requestBody
+            requestBody,
+            GameProposalActionRes.class
             );
 
-        return createdGameProposalUuid;
+        if (actionResult.failureStatus() != null) {
+            System.out.println("GameProposalActionFlow failed: " + actionResult.failureStatus());
+            throw new RuntimeException("GameProsal: ActionFlow execution has failed");
+        }
+
+        return actionResult.successStatus();
     }
 
-    private String cordaFlowExecute(HoldingIdentity holdingIdentity, RequestBody requestBody) {
+    private <T> T cordaFlowExecute(HoldingIdentity holdingIdentity, RequestBody requestBody, Class<T> flowResultType) {
 
         try {
             final String requestBodyJson = this.jsonMapper.writeValueAsString(requestBody);
@@ -134,15 +159,9 @@ public class CordaClient {
                 requestBodyJson
             );
 
-            final String flowExecutionResult = cordaFlowPoll(startedFlow);
+            final String flowResult = cordaFlowPoll(startedFlow);
 
-            // NOTE:
-            // At this point, real production code, probably should convert data between CordaFlow
-            // abstarction into ReactApp abstraction. Instead, to limit boring json shuffling, all
-            // family of Corda.List flows were deliberatly designed to return frontend frendly JSONs.
-            // At the same time, all other Corda flows, simply return plain text string with
-            // operation result.
-            return flowExecutionResult;
+            return this.jsonMapper.readValue(flowResult, flowResultType);
         } 
         catch (Exception e) {
             throw new RuntimeException("Unable to perform "+requestBody.flowClassName()
@@ -183,7 +202,7 @@ public class CordaClient {
 
         for (int retry = 0; retry < 6; retry++) {
             // Give Corda cluster some time to process our request
-            TimeUnit.SECONDS.sleep(retry*retry +1); // 1 2 5 8 17 33 sec
+            TimeUnit.SECONDS.sleep(retry*retry +2); // 2 3 6 10 18 27 sec
 
             final ResponseEntity<ResponseBody> responce = this.restTemplate.exchange(
                 "/flow/" 
@@ -204,15 +223,16 @@ public class CordaClient {
                 "CordaClient.cordaFlowPoll: empty getBody()"
             );
 
-            if (responseBody.isFlowCompleted() && responseBody.flowResult() != null) {
-                System.out.println("Completed "+responseBody.flowResult());
-                return responseBody.flowResult();
-            } else
             if (responseBody.flowError() != null) {
-                return "Flow execution error: " +responseBody.flowError();
+                throw new RuntimeException("CordaClient.cordaFlowPoll: flow execution error: " 
+                                            +responseBody.flowError());
+            }
+
+            if (responseBody.isFlowCompleted() && responseBody.flowResult() != null) {
+                return responseBody.flowResult();
             }
         }
 
-        return "CordaClient.cordaFlowPoll: retry limit";
+        throw new RuntimeException ("CordaClient.cordaFlowPoll: retry limit");
     }
 }

backend/src/main/java/djmil/cordacheckers/cordaclient/dao/GameProposal.java

@@ -1,13 +1,15 @@
 package djmil.cordacheckers.cordaclient.dao;
 
+import java.util.UUID;
+
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 
 @JsonDeserialize
 public record GameProposal(
-    String sender,
-    String recipient,
-    Color recipientColor,
+    String issuer,
+    String acquier,
+    Color acquierColor,
     String message,
-    String id) {
+    UUID id) {
     
 }

backend/src/main/java/djmil/cordacheckers/cordaclient/dao/flow/arguments/GameProposalActionReq.java

@@ -1,6 +1,6 @@
 package djmil.cordacheckers.cordaclient.dao.flow.arguments;
 
-public record GameProposalAction(String gameProposalUuid, Action action) {
+public record GameProposalActionReq(String gameProposalUuid, Action action) {
     public enum Action {
         ACCEPT,
         REJECT,

backend/src/main/java/djmil/cordacheckers/cordaclient/dao/flow/arguments/GameProposalActionRes.java

@@ -0,0 +1,5 @@
+package djmil.cordacheckers.cordaclient.dao.flow.arguments;
+
+public record GameProposalActionRes(String successStatus, String transactionId, String failureStatus) {
+    
+}

backend/src/main/java/djmil/cordacheckers/cordaclient/dao/flow/arguments/GameProposalCreateReq.java

@@ -2,6 +2,6 @@ package djmil.cordacheckers.cordaclient.dao.flow.arguments;
 
 import djmil.cordacheckers.cordaclient.dao.Color;
 
-public record CreateGameProposal(String opponentName, Color opponentColor, String message) {
+public record GameProposalCreateReq(String opponentName, Color opponentColor, String message) {
     
 }

backend/src/main/java/djmil/cordacheckers/cordaclient/dao/flow/arguments/GameProposalCreateRes.java

@@ -0,0 +1,10 @@
+package djmil.cordacheckers.cordaclient.dao.flow.arguments;
+
+import java.util.UUID;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+
+@JsonIgnoreProperties(ignoreUnknown = true)
+public record GameProposalCreateRes(UUID successStatus, String failureStatus) {
+    
+}

backend/src/main/java/djmil/cordacheckers/cordaclient/dao/flow/arguments/GameProposalListRes.java

@@ -0,0 +1,12 @@
+package djmil.cordacheckers.cordaclient.dao.flow.arguments;
+
+import java.util.List;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+
+import djmil.cordacheckers.cordaclient.dao.GameProposal;
+
+@JsonIgnoreProperties(ignoreUnknown = true)
+public record GameProposalListRes(List<GameProposal> successStatus, String failureStatus) {
+    
+}

backend/src/main/java/djmil/cordacheckers/gameproposal/GameProposalController.java

@@ -1,6 +1,8 @@
 package djmil.cordacheckers.gameproposal;
 
 import java.net.URI;
+import java.util.List;
+import java.util.UUID;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
@@ -9,9 +11,12 @@ import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.util.UriComponentsBuilder;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonMappingException;
+
 import djmil.cordacheckers.cordaclient.CordaClient;
 import djmil.cordacheckers.cordaclient.dao.HoldingIdentity;
-import djmil.cordacheckers.cordaclient.dao.flow.arguments.CreateGameProposal;
+import djmil.cordacheckers.cordaclient.dao.flow.arguments.GameProposalCreateReq;
 import djmil.cordacheckers.cordaclient.dao.Color;
 import djmil.cordacheckers.cordaclient.dao.GameProposal;
 import djmil.cordacheckers.user.HoldingIdentityResolver;
@@ -36,9 +41,9 @@ public class GameProposalController {
     public ResponseEntity<String> findAllUnconsumed(
         @AuthenticationPrincipal User player
     ) {
-        String gpList = cordaClient.listGameProposals(player.getHoldingIdentity());
+        List<GameProposal> gpList = cordaClient.gameProposalList(player.getHoldingIdentity());
 
-        return ResponseEntity.ok(gpList);
+        return ResponseEntity.ok(gpList.toString());
     }
 
     // @PostMapping()
@@ -50,15 +55,16 @@ public class GameProposalController {
     @PostMapping()
     public ResponseEntity<Void> createGameProposal(
         @AuthenticationPrincipal User sender,
-        @RequestBody CreateGameProposal gpRequest,
+        @RequestBody GameProposalCreateReq gpRequest,
         UriComponentsBuilder ucb
-    ) {
+    ) throws JsonMappingException, JsonProcessingException {
         final HoldingIdentity gpSender = sender.getHoldingIdentity();
         // TODO: throw execption with custom type
         final HoldingIdentity gpReceiver = holdingIdentityResolver.getByUsername(gpRequest.opponentName());
         final Color gpReceiverColor = gpRequest.opponentColor();
 
-        String newGameProposalUuid = cordaClient.createGameProposal(
+        // TODO handle expectionns here
+        UUID newGameProposalUuid = cordaClient.gameProposalCreate(
             gpSender,
             gpReceiver,
             gpReceiverColor,

backend/src/test/java/djmil/cordacheckers/cordaclient/CordaClientTest.java

@@ -6,14 +6,19 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonMappingException;
 
 import djmil.cordacheckers.cordaclient.dao.Color;
+import djmil.cordacheckers.cordaclient.dao.GameProposal;
 import djmil.cordacheckers.cordaclient.dao.VirtualNode;
+import djmil.cordacheckers.cordaclient.dao.flow.arguments.GameProposalActionReq.Action;
 import djmil.cordacheckers.user.HoldingIdentityResolver;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
 import java.util.List;
+import java.util.UUID;
 
 import javax.naming.InvalidNameException;
 
@@ -34,44 +39,51 @@ public class CordaClientTest {
 
     @Test
     void testGameProposalList() throws JsonProcessingException {
-        String resp = cordaClient.listGameProposals(
-            holdingIdentityResolver.getByUsername("alice"));
+        List<GameProposal> gpList = cordaClient.gameProposalList(
+            holdingIdentityResolver.getByUsername("Alice"));
 
-        System.out.println("testListGameProposals "+ resp);
+        System.out.println("testListGameProposals\n"+ gpList);
     }
 
     @Test
-    void testGemeProposalCreate() {
-        final String gpSender = "alice";
-        final String gpReceiver = "bob";
-        final Color gpReceiverColor = Color.WHITE;
+    void testGemeProposalCreate() throws JsonMappingException, JsonProcessingException {
+        final String gpIssuer = "alice";
+        final String gpAcquier = "bob";
+        final Color gpAcquierColor = Color.WHITE;
         final String gpMessage = "GameProposal create test";
 
-        final String gpUuid = cordaClient.createGameProposal(
-            holdingIdentityResolver.getByUsername(gpSender),
-            holdingIdentityResolver.getByUsername(gpReceiver),
-            gpReceiverColor,
+        final UUID createdGpUuid = cordaClient.gameProposalCreate(
+            holdingIdentityResolver.getByUsername(gpIssuer),
+            holdingIdentityResolver.getByUsername(gpAcquier),
+            gpAcquierColor,
             gpMessage
         );
 
-        String listResSender = cordaClient.listGameProposals(
-            holdingIdentityResolver.getByUsername(gpSender));
+        List<GameProposal> gpListSender = cordaClient.gameProposalList(
+            holdingIdentityResolver.getByUsername(gpIssuer));
 
-        String listResReceiver = cordaClient.listGameProposals(
-            holdingIdentityResolver.getByUsername(gpReceiver));
+        assertThat(findByUuid(gpListSender, createdGpUuid)).isNotNull();
 
-        assertThat(listResSender).contains(gpUuid);
-        assertThat(listResReceiver).contains(gpUuid);
+        List<GameProposal> gpListReceiver = cordaClient.gameProposalList(
+            holdingIdentityResolver.getByUsername(gpAcquier));
+
+        GameProposal gp;
+        assertThat(gp = findByUuid(gpListReceiver, createdGpUuid)).isNotNull();
+
+        assertThat(gp.acquier()).isEqualToIgnoringCase(gpAcquier);
+        assertThat(gp.issuer()).isEqualToIgnoringCase(gpIssuer);
+        assertThat(gp.acquierColor()).isEqualByComparingTo(gpAcquierColor);
+        assertThat(gp.message()).isEqualTo(gpMessage);
     }
 
     @Test
-    void testGemeProposalReject() {
+    void testGemeProposalReject() throws JsonMappingException, JsonProcessingException {
         final String gpSender = "alice";
         final String gpReceiver = "bob";
         final Color gpReceiverColor = Color.WHITE;
-        final String gpMessage = "GameProposal create test";
+        final String gpMessage = "GameProposal REJECT test";
 
-        final String gpUuid = cordaClient.createGameProposal(
+        final UUID gpUuid = cordaClient.gameProposalCreate(
             holdingIdentityResolver.getByUsername(gpSender),
             holdingIdentityResolver.getByUsername(gpReceiver),
             gpReceiverColor,
@@ -80,20 +92,45 @@ public class CordaClientTest {
 
         System.out.println("Create GP UUID "+ gpUuid);
 
-        String listResSender = cordaClient.listGameProposals(
-            holdingIdentityResolver.getByUsername(gpSender));
+        assertThatThrownBy(() -> {
+            cordaClient.gameProposalAction(
+                holdingIdentityResolver.getByUsername(gpSender),
+                gpUuid,
+                Action.REJECT);
+        });
 
-        String listResReceiver = cordaClient.listGameProposals(
-            holdingIdentityResolver.getByUsername(gpReceiver));
-
-        assertThat(listResSender).contains(gpUuid);
-        assertThat(listResReceiver).contains(gpUuid);
-
-        final String rejectRes = cordaClient.rejectGameProposal(
+        final String rejectRes = cordaClient.gameProposalAction(
             holdingIdentityResolver.getByUsername(gpReceiver),
-            "1ed70601-c79a-486d-b907-8537f317083a"
+            gpUuid,
+            Action.REJECT
         );
 
         assertThat(rejectRes).isEqualToIgnoringCase("REJECTED");
+
+        List<GameProposal> gpListSender = cordaClient.gameProposalList(
+            holdingIdentityResolver.getByUsername(gpSender));
+
+        assertThat(findByUuid(gpListSender, gpUuid)).isNull();
+
+        List<GameProposal> gpListReceiver = cordaClient.gameProposalList(
+            holdingIdentityResolver.getByUsername(gpReceiver));
+
+        assertThat(findByUuid(gpListReceiver, gpUuid)).isNull();
+
+        // GameProposal can not be rejected twice 
+        assertThatThrownBy(() -> {
+            cordaClient.gameProposalAction(
+                holdingIdentityResolver.getByUsername(gpSender),
+                gpUuid,
+                Action.REJECT);
+        });
+    }
+
+    private GameProposal findByUuid(List<GameProposal> gpList, UUID uuid) {
+        for (GameProposal gameProposal : gpList) {
+            if (gameProposal.id().compareTo(uuid) == 0)
+                return gameProposal;
+        };
+        return null;
     }
 }

corda/contracts/src/main/java/djmil/cordacheckers/contracts/GameProposalContract.java

@@ -3,66 +3,96 @@ package djmil.cordacheckers.contracts;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import djmil.cordacheckers.states.GameProposalResolutionState;
+//import djmil.cordacheckers.states.GameProposalResolutionState;
 import djmil.cordacheckers.states.GameProposalState;
 import net.corda.v5.base.exceptions.CordaRuntimeException;
+import net.corda.v5.base.types.MemberX500Name;
 import net.corda.v5.ledger.utxo.Command;
+import net.corda.v5.ledger.utxo.StateAndRef;
 import net.corda.v5.ledger.utxo.transaction.UtxoLedgerTransaction;
 
 public class GameProposalContract implements net.corda.v5.ledger.utxo.Contract {
 
     private final static Logger log = LoggerFactory.getLogger(GameProposalContract.class);
 
-    public static class Create implements Command { }
-    public static class Accept implements Command { }
-    public static class Reject implements Command { }
-    public static class Cancel implements Command { }
+    public static enum Action implements Command { 
+        CREATE,
+        ACCEPT,
+        REJECT,
+        CANCEL;
+
+        public MemberX500Name getInitiator(GameProposalState gameProposalState) {
+            switch (this) {
+                case CREATE:
+                case CANCEL:
+                    return gameProposalState.getIssuer();
+                case ACCEPT:
+                case REJECT:
+                    return gameProposalState.getAcquier();
+                default:
+                    throw new RuntimeException(UNSUPPORTED_ACTION_VALUE_OF + this.name());
+            }
+        }
+
+        public MemberX500Name getRespondent(GameProposalState gameProposalState) {
+            switch (this) {
+                case CREATE:
+                case CANCEL:
+                    return gameProposalState.getAcquier();
+                case ACCEPT:
+                case REJECT:
+                    return gameProposalState.getIssuer();
+                default:
+                    throw new RuntimeException(UNSUPPORTED_ACTION_VALUE_OF + this.name());
+            }
+        }
+
+        public MemberX500Name getSender(StateAndRef<GameProposalState> utxoGameProposal) {
+            return getInitiator(utxoGameProposal.getState().getContractState());
+        }
+
+        public MemberX500Name getReceiver(StateAndRef<GameProposalState> utxoGameProposal) {
+            return getRespondent(utxoGameProposal.getState().getContractState());
+        }
+
+        public static final String UNSUPPORTED_ACTION_VALUE_OF = "Unsupported Action value: ";
+    }
 
     @Override
     public void verify(UtxoLedgerTransaction trx) {
         log.info("GameProposalContract.verify() called");
 
         requireThat(trx.getCommands().size() == 1, REQUIRE_SINGLE_COMMAND);
-        Command command = trx.getCommands().get(0);
 
-        if (command instanceof Create) {
-            requireThat(trx.getInputContractStates().isEmpty(), CREATE_INPUT_STATE);
-            requireThat(trx.getOutputContractStates().size() == 1, CREATE_OUTPUT_STATE);
-            
-            GameProposalState outputState = trx.getOutputStates(GameProposalState.class).get(0);
-            requireThat(outputState != null, CREATE_OUTPUT_STATE);
+        switch ((Action)(trx.getCommands().get(0))) {
+            case CREATE: {
+                requireThat(trx.getInputContractStates().isEmpty(), CREATE_INPUT_STATE);
+                requireThat(trx.getOutputContractStates().size() == 1, CREATE_OUTPUT_STATE);
 
-            requireThat(outputState.getRecipientColor() != null, NON_NULL_RECIPIENT_COLOR);
-        } else 
-        if (command instanceof Accept) {
-            // TODO outputState -> Game
-            throw new CordaRuntimeException("Unimplemented!");
-        } else 
-        if (command instanceof Reject) {
-            requireThat(trx.getInputContractStates().size() == 1, REJECT_INPUT_STATE);
-            requireThat(trx.getOutputContractStates().size() == 1, REJECT_OUTPUT_STATE);
+                GameProposalState outputState = trx.getOutputStates(GameProposalState.class).get(0);
+                requireThat(outputState != null, CREATE_OUTPUT_STATE);
 
-            GameProposalState inputState = trx.getInputStates(GameProposalState.class).get(0);
-            requireThat(inputState != null, REJECT_INPUT_STATE);
-            
-            GameProposalResolutionState outputState = trx.getOutputStates(GameProposalResolutionState.class).get(0);
-            requireThat(outputState != null, REJECT_OUTPUT_STATE);
+                requireThat(outputState.getRecipientColor() != null, NON_NULL_RECIPIENT_COLOR);
+                break; }
 
-            requireThat(outputState.outcome == GameProposalResolutionState.Resolution.REJECT, REJECT_OUTPUT_OUTCOME);
-        } else 
-        if (command instanceof Cancel) {
-            requireThat(trx.getInputContractStates().size() == 1, CANCEL_INPUT_STATE);
-            requireThat(trx.getOutputContractStates().size() == 1, CANCEL_OUTPUT_STATE);
+            case ACCEPT:
+                throw new CordaRuntimeException("Unimplemented!");
+                //break; 
 
-            GameProposalState inputState = trx.getInputStates(GameProposalState.class).get(0);
-            requireThat(inputState != null, CANCEL_INPUT_STATE);
-            
-            GameProposalResolutionState outputState = trx.getOutputStates(GameProposalResolutionState.class).get(0);
-            requireThat(outputState != null, CANCEL_OUTPUT_STATE);
+            case REJECT:
+                requireThat(trx.getInputContractStates().size() == 1, REJECT_INPUT_STATE);
+                requireThat(trx.getOutputContractStates().isEmpty(), REJECT_OUTPUT_STATE);
+                requireThat(trx.getInputStates(GameProposalState.class).get(0) != null, REJECT_INPUT_STATE);
+                break;
 
-            requireThat(outputState.outcome == GameProposalResolutionState.Resolution.CANCEL, CANCEL_OUTPUT_OUTCOME);
-        } else {
-            throw new CordaRuntimeException(UNKNOWN_COMMAND);
+            case CANCEL:
+                requireThat(trx.getInputContractStates().size() == 1, CANCEL_INPUT_STATE);
+                requireThat(trx.getOutputContractStates().isEmpty(), CANCEL_OUTPUT_STATE);
+                requireThat(trx.getInputStates(GameProposalState.class).get(0) != null, CANCEL_INPUT_STATE);
+                break;
+
+            default:
+                throw new CordaRuntimeException(UNKNOWN_COMMAND);
         }
     }
     
@@ -80,10 +110,8 @@ public class GameProposalContract implements net.corda.v5.ledger.utxo.Contract {
     static final String NON_NULL_RECIPIENT_COLOR = "GameProposal.recipientColor field can not be null";
 
     static final String REJECT_INPUT_STATE  = "Reject command should have exactly one GameProposal input state";
-    static final String REJECT_OUTPUT_STATE = "Reject command should have exactly one GameProposalResolution output states";
-    static final String REJECT_OUTPUT_OUTCOME = "Reject output state should have Resolution value set to REJECT";
+    static final String REJECT_OUTPUT_STATE = "Reject command should have no output states";
 
     static final String CANCEL_INPUT_STATE  = "Cancel command should have exactly one GameProposal input state";
-    static final String CANCEL_OUTPUT_STATE = "Cancel command should have exactly one GameProposalResolution output states";
-    static final String CANCEL_OUTPUT_OUTCOME = "Cancel output state should have Resolution value set to CANCEL";
+    static final String CANCEL_OUTPUT_STATE = "Cancel command should have no output states";
 }

corda/contracts/src/main/java/djmil/cordacheckers/states/GameProposalResolutionState.java

@@ -1,63 +0,0 @@
-package djmil.cordacheckers.states;
-
-import java.security.PublicKey;
-import java.util.List;
-
-import djmil.cordacheckers.contracts.GameProposalContract;
-import net.corda.v5.base.annotations.ConstructorForDeserialization;
-import net.corda.v5.base.annotations.CordaSerializable;
-import net.corda.v5.base.types.MemberX500Name;
-import net.corda.v5.ledger.utxo.BelongsToContract;
-import net.corda.v5.ledger.utxo.ContractState;
-
-@BelongsToContract(GameProposalContract.class)
-public class GameProposalResolutionState implements ContractState {
-
-    @CordaSerializable
-    public enum Resolution {
-        ACCEPT,
-        REJECT,
-        CANCEL
-    }
-
-    public final Resolution outcome;
-    public final List<PublicKey> participants;
-
-    public GameProposalResolutionState(
-        Resolution outcome,
-        GameProposalState gameProposal
-    ) {
-        this.outcome = outcome;
-        this.participants = gameProposal.getParticipants();
-    }
-
-    @ConstructorForDeserialization
-    public GameProposalResolutionState(
-        Resolution outcome,
-        List<PublicKey> participants
-    ) {
-        this.outcome = outcome;
-        this.participants = participants;
-    }
-
-    public Resolution getOutcome() {
-        return outcome;
-    }
-
-    public List<PublicKey> getParticipants() {
-        return this.participants;
-    }
-
-    public MemberX500Name getRecipient(GameProposalState gameProposal) {
-        switch (outcome) {
-            case ACCEPT:
-            case REJECT:
-                return gameProposal.getSender();
-            case CANCEL:
-                return gameProposal.getRecipient();
-            default:
-                throw new RuntimeException("Unknown Resolution value: "+outcome.toString());
-        }
-    }
-    
-}

corda/contracts/src/main/java/djmil/cordacheckers/states/GameProposalState.java

@@ -6,7 +6,6 @@ import java.util.UUID;
 
 import djmil.cordacheckers.contracts.GameProposalContract;
 import net.corda.v5.base.annotations.ConstructorForDeserialization;
-import net.corda.v5.base.annotations.CordaSerializable;
 import net.corda.v5.base.types.MemberX500Name;
 import net.corda.v5.ledger.utxo.BelongsToContract;
 import net.corda.v5.ledger.utxo.ContractState;
@@ -14,46 +13,40 @@ import net.corda.v5.ledger.utxo.ContractState;
 @BelongsToContract(GameProposalContract.class)
 public class GameProposalState implements ContractState {
 
-    @CordaSerializable
-    public enum Color {
-        WHITE,
-        BLACK,
-    }
-      
-    public final MemberX500Name sender;
-    public final MemberX500Name recipient;
-    public final Color recipientColor;
-    public final String message;
-    public final UUID id;
-    public final List<PublicKey> participants;
+    MemberX500Name issuer;
+    MemberX500Name acquier;
+    Piece.Color recipientColor;
+    String message;
+    UUID id;
+    List<PublicKey> participants;
 
     // Allows serialisation and to use a specified UUID
     @ConstructorForDeserialization
     public GameProposalState(
-        MemberX500Name sender,
-        MemberX500Name recipient,
-        Color recipientColor,
+        MemberX500Name issuer,
+        MemberX500Name acquier,
+        Piece.Color recipientColor,
         String message,
         UUID id,
         List<PublicKey> participants
     ) {
-        this.sender = sender;
-        this.recipient = recipient;
+        this.issuer = issuer;
+        this.acquier = acquier;
         this.recipientColor = recipientColor;
         this.message = message;
         this.id = id;
         this.participants = participants;
     }
 
-    public MemberX500Name getSender() {
-        return sender;
+    public MemberX500Name getIssuer() {
+        return issuer;
     }
 
-    public MemberX500Name getRecipient() {
-        return recipient;
+    public MemberX500Name getAcquier() {
+        return acquier;
     }
 
-    public Color getRecipientColor() {
+    public Piece.Color getRecipientColor() {
         return recipientColor;
     }
 

corda/contracts/src/main/java/djmil/cordacheckers/states/Piece.java

@@ -0,0 +1,24 @@
+package djmil.cordacheckers.states;
+
+import net.corda.v5.base.annotations.CordaSerializable;
+
+@CordaSerializable
+public class Piece {
+    
+    @CordaSerializable
+    public enum Type {
+        MAN,
+        KING,
+    }
+
+    @CordaSerializable
+    public enum Color {
+        WHITE,
+        BLACK,
+    }
+
+    Color color;
+    Type type;
+
+    
+}

corda/workflows/src/main/java/djmil/cordacheckers/FlowResult.java

@@ -1,18 +1,28 @@
 package djmil.cordacheckers;
 
 import net.corda.v5.application.marshalling.JsonMarshallingService;
+import net.corda.v5.crypto.SecureHash;
 
 public class FlowResult {
     public final Object successStatus;
+    public final String transactionId;
     public final String failureStatus;
 
     public FlowResult(Object success) {
         this.successStatus = success;
+        this.transactionId = null;
+        this.failureStatus = null;
+    }
+
+    public FlowResult(Object success, SecureHash transactionId) {
+        this.successStatus = success;
+        this.transactionId = transactionId.toString();
         this.failureStatus = null;
     }
 
     public FlowResult(Exception exception) {
         this.successStatus = null;
+        this.transactionId = null;
         this.failureStatus = exception.getMessage();
     }
 

corda/workflows/src/main/java/djmil/cordacheckers/gameproposal/ActionFlow.java

@@ -1,8 +1,6 @@
 package djmil.cordacheckers.gameproposal;
 
-import java.util.Arrays;
 import java.util.List;
-import java.util.Map;
 import java.util.UUID;
 import java.util.stream.Collectors;
 
@@ -10,21 +8,15 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import djmil.cordacheckers.FlowResult;
-import djmil.cordacheckers.contracts.GameProposalContract;
-import djmil.cordacheckers.states.GameProposalResolutionState;
 import djmil.cordacheckers.states.GameProposalState;
 import net.corda.v5.application.flows.ClientRequestBody;
 import net.corda.v5.application.flows.ClientStartableFlow;
 import net.corda.v5.application.flows.CordaInject;
-import net.corda.v5.application.flows.InitiatingFlow;
+import net.corda.v5.application.flows.FlowEngine;
 import net.corda.v5.application.marshalling.JsonMarshallingService;
-import net.corda.v5.application.membership.MemberLookup;
-import net.corda.v5.application.messaging.FlowMessaging;
-import net.corda.v5.application.messaging.FlowSession;
 import net.corda.v5.base.annotations.Suspendable;
 import net.corda.v5.base.exceptions.CordaRuntimeException;
-import net.corda.v5.base.types.MemberX500Name;
-import net.corda.v5.ledger.utxo.Command;
+import net.corda.v5.crypto.SecureHash;
 import net.corda.v5.ledger.utxo.StateAndRef;
 import net.corda.v5.ledger.utxo.UtxoLedgerService;
 import net.corda.v5.ledger.utxo.transaction.UtxoSignedTransaction;
@@ -33,7 +25,8 @@ import net.corda.v5.ledger.utxo.transaction.UtxoTransactionBuilder;
 import java.time.Duration;
 import java.time.Instant;
 
-@InitiatingFlow(protocol = "game-proposal-action")
+import static djmil.cordacheckers.contracts.GameProposalContract.Action;
+
 public class ActionFlow implements ClientStartableFlow {
 
     private final static Logger log = LoggerFactory.getLogger(CreateFlow.class);
@@ -45,33 +38,24 @@ public class ActionFlow implements ClientStartableFlow {
     public UtxoLedgerService ledgerService;
 
     @CordaInject
-    public FlowMessaging flowMessaging;
-
-    @CordaInject
-    public MemberLookup memberLookup;
-
-    private final static Map<GameProposalResolutionState.Resolution, Command> resoultion2command = Map.ofEntries(
-        Map.entry(GameProposalResolutionState.Resolution.CANCEL, new GameProposalContract.Cancel()),
-        Map.entry(GameProposalResolutionState.Resolution.REJECT, new GameProposalContract.Reject()),
-        Map.entry(GameProposalResolutionState.Resolution.ACCEPT, new GameProposalContract.Accept())
-    );
+    public FlowEngine flowEngine;
 
     @Override
     @Suspendable
     public String call(ClientRequestBody requestBody) {
         try {
-            ActionFlowArgs args = requestBody.getRequestBodyAs(jsonMarshallingService, ActionFlowArgs.class);
+            final ActionFlowArgs args = requestBody.getRequestBodyAs(jsonMarshallingService, ActionFlowArgs.class);
+            final Action action = args.getAction();
 
-            StateAndRef<GameProposalState> inputState = findUnconsumedGameProposalState(args.getGameProposalUuid());
-        
-            GameProposalResolutionState outputState = new GameProposalResolutionState(
-                args.getAction(),
-                inputState.getState().getContractState()
-                );
+            final StateAndRef<GameProposalState> inputState = findUnconsumedGameProposalState(args.getGameProposalUuid());
 
-            String trxResult = doTrunsaction(inputState, outputState);
+            final UtxoSignedTransaction trx = prepareSignedTransaction(action, inputState);
 
-            return new FlowResult(trxResult).toJsonEncodedString(jsonMarshallingService);
+            final SecureHash trxId = this.flowEngine
+                .subFlow( new CommitSubFlow(trx, action.getReceiver(inputState)) );
+
+            return new FlowResult(action+"ED", trxId)  // REJECT+ED
+                .toJsonEncodedString(jsonMarshallingService);
         } 
         catch (Exception e) {
             log.warn("GameProposalAction flow failed to process utxo request body " + requestBody + 
@@ -83,7 +67,7 @@ public class ActionFlow implements ClientStartableFlow {
     @Suspendable
     private StateAndRef<GameProposalState> findUnconsumedGameProposalState (UUID gameProposalUuid) {
         /*
-         * Get list of all unconsumed aka 'actuve' GameProposalStates, then filter by UUID.
+         * Get list of all unconsumed aka 'active' GameProposalStates, then filter by UUID.
          * Note, this is an inefficient way to perform this operation if there are a large
          * number of 'active' GameProposals exists in storage.
          */
@@ -102,26 +86,24 @@ public class ActionFlow implements ClientStartableFlow {
     }
 
     @Suspendable
-    private String doTrunsaction(StateAndRef<GameProposalState> inputState, GameProposalResolutionState outputState) {
-        UtxoTransactionBuilder txBuilder = ledgerService.createTransactionBuilder()
+    private UtxoSignedTransaction prepareSignedTransaction(
+        Action action,
+        StateAndRef<GameProposalState> inputState
+    ) {
+        UtxoTransactionBuilder trxBuilder = ledgerService.createTransactionBuilder()
             .setNotary(inputState.getState().getNotaryName())
             .setTimeWindowBetween(Instant.now(), Instant.now().plusMillis(Duration.ofDays(1).toMillis()))
             .addInputState(inputState.getRef())
-            .addOutputState(outputState)
-            .addCommand(resoultion2command.get(outputState.outcome))
-            .addSignatories(outputState.getParticipants());
+            .addCommand(action)
+            .addSignatories(inputState.getState().getContractState().getParticipants());
 
-        UtxoSignedTransaction signedTransaction = txBuilder.toSignedTransaction();
+        if (action == Action.ACCEPT) {
+            // TODO
+            // .addOutputState(outputState)
+            throw new RuntimeException(action +" unimplemented");
+        }
 
-        FlowSession session = flowMessaging.initiateFlow(
-            outputState.getRecipient(inputState.getState().getContractState())
-            );
-
-        List<FlowSession> sessionsList = Arrays.asList(session);
-
-        ledgerService.finalize(signedTransaction, sessionsList);
-
-        return outputState.getOutcome()+"ED"; // REJECT+ED
+        return trxBuilder.toSignedTransaction();
     }
 
 }

corda/workflows/src/main/java/djmil/cordacheckers/gameproposal/ActionFlowArgs.java

@@ -2,8 +2,7 @@ package djmil.cordacheckers.gameproposal;
 
 import java.util.UUID;
 
-import djmil.cordacheckers.states.GameProposalResolutionState;
-import djmil.cordacheckers.states.GameProposalResolutionState.Resolution;
+import djmil.cordacheckers.contracts.GameProposalContract;
 
 public class ActionFlowArgs {
     private UUID gameProposalUuid;
@@ -15,8 +14,8 @@ public class ActionFlowArgs {
         this.action = null;
     }
     
-    public Resolution getAction() {
-        return GameProposalResolutionState.Resolution.valueOf(this.action);
+    public GameProposalContract.Action getAction() {
+        return GameProposalContract.Action.valueOf(this.action);
     }
 
     public UUID getGameProposalUuid() {

corda/workflows/src/main/java/djmil/cordacheckers/gameproposal/ActionResponder.java

@@ -1,83 +0,0 @@
-package djmil.cordacheckers.gameproposal;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import djmil.cordacheckers.contracts.GameProposalContract.Accept;
-import djmil.cordacheckers.contracts.GameProposalContract.Cancel;
-import djmil.cordacheckers.contracts.GameProposalContract.Reject;
-import djmil.cordacheckers.states.GameProposalState;
-import net.corda.v5.application.flows.CordaInject;
-import net.corda.v5.application.flows.InitiatedBy;
-import net.corda.v5.application.flows.ResponderFlow;
-import net.corda.v5.application.membership.MemberLookup;
-import net.corda.v5.application.messaging.FlowSession;
-import net.corda.v5.base.annotations.Suspendable;
-import net.corda.v5.base.exceptions.CordaRuntimeException;
-import net.corda.v5.base.types.MemberX500Name;
-import net.corda.v5.ledger.utxo.Command;
-import net.corda.v5.ledger.utxo.UtxoLedgerService;
-import net.corda.v5.ledger.utxo.transaction.UtxoSignedTransaction;
-import net.corda.v5.ledger.utxo.transaction.UtxoTransactionValidator;
-
-@InitiatedBy(protocol = "game-proposal-action")
-public class ActionResponder implements ResponderFlow {
-    private final static Logger log = LoggerFactory.getLogger(CreateResponder.class);
-
-    @CordaInject
-    public MemberLookup memberLookup;
-
-    @CordaInject
-    public UtxoLedgerService utxoLedgerService;
-    
-    @Suspendable
-    @Override
-    public void call(FlowSession session) {
-        try {
-            UtxoTransactionValidator txValidator = ledgerTransaction -> {
-                GameProposalState gameProposal = (GameProposalState) ledgerTransaction.getInputContractStates().get(0);
-
-                Command command = ledgerTransaction.getCommands(Command.class).get(0);
-
-                if (!checkParticipants(gameProposal, session.getCounterparty(), command)) {
-                    throw new CordaRuntimeException("Failed verification");
-                }
-
-                log.info("Verified the transaction - " + ledgerTransaction.getId());
-            };
-
-            // Calls receiveFinality() function which provides the responder to the finalise() function
-            // in the Initiating Flow. Accepts a lambda validator containing the business logic to decide whether
-            // responder should sign the Transaction.
-            UtxoSignedTransaction finalizedSignedTransaction = utxoLedgerService
-                    .receiveFinality(session, txValidator)
-                    .getTransaction();
-
-            log.info("Finished responder flow - " + finalizedSignedTransaction.getId());
-        }
-        // Soft fails the flow and log the exception.
-        catch(Exception e)
-        {
-            log.warn("Exceptionally finished responder flow", e);
-        }
-    }
-
-    @Suspendable
-    Boolean checkParticipants(GameProposalState gameProposal, MemberX500Name counterpartyName, Command command) {
-        MemberX500Name myName = memberLookup.myInfo().getName();
-
-        if (command instanceof Reject || command instanceof Accept) {
-            if (gameProposal.getRecipient().compareTo(counterpartyName) == 0 && 
-                gameProposal.getSender().compareTo(myName) == 0)
-                return true;
-        }
-
-        if (command instanceof Cancel) {
-            if (gameProposal.getRecipient().compareTo(myName) == 0 && 
-                gameProposal.getSender().compareTo(counterpartyName) == 0)
-                return true;
-        }
-
-        return false;
-    }
-}

corda/workflows/src/main/java/djmil/cordacheckers/gameproposal/CommitResponderFlow.java

@@ -0,0 +1,95 @@
+package djmil.cordacheckers.gameproposal;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import djmil.cordacheckers.states.GameProposalState;
+import net.corda.v5.application.flows.CordaInject;
+import net.corda.v5.application.flows.InitiatedBy;
+import net.corda.v5.application.flows.ResponderFlow;
+import net.corda.v5.application.membership.MemberLookup;
+import net.corda.v5.application.messaging.FlowSession;
+import net.corda.v5.base.annotations.Suspendable;
+import net.corda.v5.base.exceptions.CordaRuntimeException;
+import net.corda.v5.base.types.MemberX500Name;
+import net.corda.v5.ledger.utxo.UtxoLedgerService;
+import net.corda.v5.ledger.utxo.transaction.UtxoLedgerTransaction;
+import net.corda.v5.ledger.utxo.transaction.UtxoSignedTransaction;
+import net.corda.v5.ledger.utxo.transaction.UtxoTransactionValidator;
+
+import static djmil.cordacheckers.contracts.GameProposalContract.Action;
+
+@InitiatedBy(protocol = "game-proposal")
+public class CommitResponderFlow implements ResponderFlow {
+    private final static Logger log = LoggerFactory.getLogger(CommitResponderFlow.class);
+
+    @CordaInject
+    public MemberLookup memberLookup;
+
+    @CordaInject
+    public UtxoLedgerService utxoLedgerService;
+    
+    @Suspendable
+    @Override
+    public void call(FlowSession session) {
+        try {
+            UtxoTransactionValidator txValidator = ledgerTransaction -> {
+                final Action action = ledgerTransaction.getCommands(Action.class).get(0);
+
+                final GameProposalState gameProposal = getGameProposal(ledgerTransaction); 
+
+                checkSessionParticipants(session, gameProposal, action);
+
+                /*
+                 * Other checks / actions ?
+                 */
+
+                log.info("Verified the transaction - " + ledgerTransaction.getId());
+            };
+
+            UtxoSignedTransaction finalizedSignedTransaction = utxoLedgerService
+                    .receiveFinality(session, txValidator)
+                    .getTransaction();
+
+            log.info("Finished responder flow - " + finalizedSignedTransaction.getId());
+        }
+        catch(Exception e) {
+            log.warn("Responder flow failed: ", e);
+        }
+    }
+
+    @Suspendable
+    void checkSessionParticipants(
+        FlowSession session,
+        GameProposalState gameProposal,
+        Action action
+    ) {
+        final MemberX500Name myName = memberLookup.myInfo().getName();
+        final MemberX500Name otherName = session.getCounterparty();
+
+        if (action.getRespondent(gameProposal).compareTo(myName) != 0)
+            throw new CordaRuntimeException("Bad GameProposal acquirer: expected '"+myName+"', actual '" +gameProposal.getAcquier() +"'");
+        
+        if (action.getInitiator(gameProposal).compareTo(otherName) != 0)
+            throw new CordaRuntimeException("Bad GameProposal issuer: expected '"+otherName+"', actual '"+gameProposal.getIssuer()+"'");
+    }
+
+    @Suspendable
+    GameProposalState getGameProposal(UtxoLedgerTransaction trx) {
+        final Action action = trx.getCommands(Action.class).get(0);
+        
+        switch (action) {
+            case CREATE:
+                return (GameProposalState)trx.getOutputContractStates().get(0);
+
+            case ACCEPT:
+            case REJECT:
+            case CANCEL:
+                return (GameProposalState)trx.getInputContractStates().get(0);
+
+            default:
+                throw new RuntimeException(Action.UNSUPPORTED_ACTION_VALUE_OF +action);
+        }
+
+    }
+}

corda/workflows/src/main/java/djmil/cordacheckers/gameproposal/CommitSubFlow.java

@@ -0,0 +1,60 @@
+package djmil.cordacheckers.gameproposal;
+
+import java.util.Arrays;
+import java.util.List;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import net.corda.v5.application.flows.CordaInject;
+import net.corda.v5.application.flows.InitiatingFlow;
+import net.corda.v5.application.flows.SubFlow;
+import net.corda.v5.application.messaging.FlowMessaging;
+import net.corda.v5.application.messaging.FlowSession;
+import net.corda.v5.base.annotations.Suspendable;
+import net.corda.v5.base.types.MemberX500Name;
+import net.corda.v5.crypto.SecureHash;
+import net.corda.v5.ledger.utxo.UtxoLedgerService;
+import net.corda.v5.ledger.utxo.transaction.UtxoSignedTransaction;
+
+@InitiatingFlow(protocol = "game-proposal")
+public class CommitSubFlow implements SubFlow<SecureHash> {
+
+    private final static Logger log = LoggerFactory.getLogger(CommitSubFlow.class);
+    private final UtxoSignedTransaction signedTransaction;
+    private final MemberX500Name respondenName;
+
+    public CommitSubFlow(UtxoSignedTransaction signedTransaction, MemberX500Name respondenName) {
+        this.signedTransaction = signedTransaction;
+        this.respondenName = respondenName;
+    }
+
+    @CordaInject
+    public UtxoLedgerService ledgerService;
+
+    @CordaInject
+    public FlowMessaging flowMessaging;
+
+    @Override
+    @Suspendable
+    public SecureHash call() {
+        log.info("GamePropsal commit started");
+
+        final FlowSession session = flowMessaging.initiateFlow(this.respondenName);
+
+        /*
+         * Calls the Corda provided finalise() function which gather signatures from the counterparty,
+         * notarises the transaction and persists the transaction to each party's vault.
+         */
+
+        final List<FlowSession> sessionsList = Arrays.asList(session);
+
+        final SecureHash trxId = ledgerService
+            .finalize(this.signedTransaction, sessionsList)
+            .getTransaction()
+            .getId();
+
+        log.info("GamePropsal commit " +trxId);
+        return trxId;
+    }
+}

corda/workflows/src/main/java/djmil/cordacheckers/gameproposal/CreateFlow.java

@@ -4,8 +4,8 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import djmil.cordacheckers.FlowResult;
-import djmil.cordacheckers.contracts.GameProposalContract;
 import djmil.cordacheckers.states.GameProposalState;
+import djmil.cordacheckers.states.Piece;
 import net.corda.v5.application.flows.ClientRequestBody;
 import net.corda.v5.application.flows.ClientStartableFlow;
 import net.corda.v5.application.flows.CordaInject;
@@ -13,26 +13,23 @@ import net.corda.v5.application.flows.FlowEngine;
 import net.corda.v5.application.flows.InitiatingFlow;
 import net.corda.v5.application.marshalling.JsonMarshallingService;
 import net.corda.v5.application.membership.MemberLookup;
-import net.corda.v5.application.messaging.FlowMessaging;
-import net.corda.v5.application.messaging.FlowSession;
 import net.corda.v5.base.annotations.Suspendable;
 import net.corda.v5.base.types.MemberX500Name;
+import net.corda.v5.crypto.SecureHash;
 import net.corda.v5.ledger.common.NotaryLookup;
 import net.corda.v5.ledger.utxo.UtxoLedgerService;
 import net.corda.v5.ledger.utxo.transaction.UtxoSignedTransaction;
-import net.corda.v5.ledger.utxo.transaction.UtxoTransactionBuilder;
 import net.corda.v5.membership.MemberInfo;
 import net.corda.v5.membership.NotaryInfo;
 
 import static java.util.Objects.requireNonNull;
+import static djmil.cordacheckers.contracts.GameProposalContract.Action;
 
 import java.time.Duration;
 import java.time.Instant;
 import java.util.Arrays;
-import java.util.List;
 import java.util.UUID;
 
-@InitiatingFlow(protocol = "game-proposal-create")
 public class CreateFlow implements ClientStartableFlow{
 
      private final static Logger log = LoggerFactory.getLogger(CreateFlow.class);
@@ -52,19 +49,22 @@ public class CreateFlow implements ClientStartableFlow{
      @CordaInject
      public FlowEngine flowEngine;
 
-     @CordaInject
-     public FlowMessaging flowMessaging;
-
      @Suspendable
      @Override
      public String call(ClientRequestBody requestBody) {
           try {
                log.info("flow: Create Game Proposal");
+               final Action actino = Action.CREATE;
 
-               GameProposalState gameProposal = buildGameProposalStateFrom(requestBody);
-               String trxResult = doTrunsaction(gameProposal);
+               final GameProposalState newGameProposal = buildGameProposalStateFrom(requestBody);
+               
+               final UtxoSignedTransaction trx = prepareSignedTransaction(newGameProposal);
 
-               return new FlowResult(trxResult).toJsonEncodedString(jsonMarshallingService);
+               final SecureHash trxId = this.flowEngine
+                    .subFlow(new CommitSubFlow(trx, actino.getRespondent(newGameProposal)));
+
+               return new FlowResult(newGameProposal.getId(), trxId)
+                    .toJsonEncodedString(jsonMarshallingService);
           } 
           catch (Exception e) {
                log.warn("CreateGameProposal flow failed to process utxo request body " + requestBody + 
@@ -77,10 +77,10 @@ public class CreateFlow implements ClientStartableFlow{
      private GameProposalState buildGameProposalStateFrom(ClientRequestBody requestBody) {
           CreateFlowArgs args = requestBody.getRequestBodyAs(jsonMarshallingService, CreateFlowArgs.class);
 
-          GameProposalState.Color opponentColor = GameProposalState.Color.valueOf(args.opponentColor);
+          Piece.Color opponentColor = Piece.Color.valueOf(args.opponentColor);
           if (opponentColor == null) {
                throw new RuntimeException("Allowed values for opponentColor are: "
-                    + GameProposalState.Color.WHITE.name() +", "  + GameProposalState.Color.BLACK.name() 
+                    + Piece.Color.WHITE.name() +", "  + Piece.Color.BLACK.name() 
                     + ". Actual value was: " + args.opponentColor);
           }
 
@@ -101,24 +101,15 @@ public class CreateFlow implements ClientStartableFlow{
      }
 
      @Suspendable
-     private String doTrunsaction(GameProposalState gameProposal) {     
-          NotaryInfo notary = notaryLookup.getNotaryServices().iterator().next();
+     private UtxoSignedTransaction prepareSignedTransaction(GameProposalState outputGameProposalState) {     
+          final NotaryInfo notary = notaryLookup.getNotaryServices().iterator().next();
 
-          UtxoTransactionBuilder txBuilder = ledgerService.createTransactionBuilder()
+          return ledgerService.createTransactionBuilder()
                .setNotary(notary.getName())
                .setTimeWindowBetween(Instant.now(), Instant.now().plusMillis(Duration.ofDays(1).toMillis()))
-               .addOutputState(gameProposal)
-               .addCommand(new GameProposalContract.Create())
-               .addSignatories(gameProposal.getParticipants());
-
-          UtxoSignedTransaction signedTransaction = txBuilder.toSignedTransaction();
-
-          FlowSession session = flowMessaging.initiateFlow(gameProposal.getRecipient());
-
-          List<FlowSession> sessionsList = Arrays.asList(session);
-
-          ledgerService.finalize(signedTransaction, sessionsList);
-
-          return gameProposal.id.toString();
+               .addOutputState(outputGameProposalState)
+               .addCommand(Action.CREATE)
+               .addSignatories(outputGameProposalState.getParticipants())
+               .toSignedTransaction();
      }
 }

corda/workflows/src/main/java/djmil/cordacheckers/gameproposal/CreateResponder.java

@@ -1,72 +0,0 @@
-package djmil.cordacheckers.gameproposal;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import djmil.cordacheckers.states.GameProposalState;
-import net.corda.v5.application.flows.CordaInject;
-import net.corda.v5.application.flows.InitiatedBy;
-import net.corda.v5.application.flows.ResponderFlow;
-import net.corda.v5.application.membership.MemberLookup;
-import net.corda.v5.application.messaging.FlowSession;
-import net.corda.v5.base.annotations.Suspendable;
-import net.corda.v5.base.exceptions.CordaRuntimeException;
-import net.corda.v5.base.types.MemberX500Name;
-import net.corda.v5.ledger.utxo.UtxoLedgerService;
-import net.corda.v5.ledger.utxo.transaction.UtxoSignedTransaction;
-import net.corda.v5.ledger.utxo.transaction.UtxoTransactionValidator;
-
-@InitiatedBy(protocol = "game-proposal-create")
-public class CreateResponder implements ResponderFlow {
-    private final static Logger log = LoggerFactory.getLogger(CreateResponder.class);
-
-    @CordaInject
-    public MemberLookup memberLookup;
-
-    @CordaInject
-    public UtxoLedgerService utxoLedgerService;
-    
-    @Suspendable
-    @Override
-    public void call(FlowSession session) {
-        try {
-            // Defines the lambda validator used in receiveFinality below.
-            UtxoTransactionValidator txValidator = ledgerTransaction -> {
-                GameProposalState gameProposal = (GameProposalState) ledgerTransaction.getOutputContractStates().get(0);
-                // Uses checkForBannedWords() and checkMessageFromMatchesCounterparty() functions
-                // to check whether to sign the transaction.
-                if (!checkParticipants(gameProposal, session.getCounterparty())) {
-                    throw new CordaRuntimeException("Failed verification");
-                }
-
-                log.info("Verified the transaction - " + ledgerTransaction.getId());
-            };
-
-            // Calls receiveFinality() function which provides the responder to the finalise() function
-            // in the Initiating Flow. Accepts a lambda validator containing the business logic to decide whether
-            // responder should sign the Transaction.
-            UtxoSignedTransaction finalizedSignedTransaction = utxoLedgerService
-                    .receiveFinality(session, txValidator)
-                    .getTransaction();
-
-            log.info("Finished responder flow - " + finalizedSignedTransaction.getId());
-        }
-        // Soft fails the flow and log the exception.
-        catch(Exception e)
-        {
-            log.warn("Exceptionally finished responder flow", e);
-        }
-    }
-
-    @Suspendable
-    Boolean checkParticipants(GameProposalState gameProposal, MemberX500Name counterpartyName) {
-        MemberX500Name myName = memberLookup.myInfo().getName();
-
-        if (gameProposal.getRecipient().compareTo(myName) == 0 && 
-            gameProposal.getSender().compareTo(counterpartyName) == 0)
-            return true;
-    
-        return false;
-    }
-    
-}

corda/workflows/src/main/java/djmil/cordacheckers/gameproposal/ListItem.java

@@ -10,26 +10,26 @@ import djmil.cordacheckers.states.GameProposalState;
 // and a UUID. It is possible to create custom serializers for the JsonMarshallingService in the future.
 
 public class ListItem {
-    public final String sender;
-    public final String recipient;
-    public final String recipientColor;
+    public final String issuer;
+    public final String acquier;
+    public final String acquierColor;
     public final String message;
     public final UUID id;
 
     // Serialisation service requires a default constructor
     public ListItem() { 
-        this.sender = null;
-        this.recipient = null;
-        this.recipientColor = null;
+        this.issuer = null;
+        this.acquier = null;
+        this.acquierColor = null;
         this.message = null;
         this.id = null;
     }
 
     public ListItem(GameProposalState state) {
-        this.sender    = state.getSender().getCommonName();
-        this.recipient = state.getRecipient().getCommonName();
-        this.recipientColor = state.getRecipientColor().name();
-        this.message   = state.getMessage();
-        this.id        = state.getId();
+        this.issuer  = state.getIssuer().getCommonName();
+        this.acquier = state.getAcquier().getCommonName();
+        this.acquierColor = state.getRecipientColor().name();
+        this.message = state.getMessage();
+        this.id      = state.getId();
     }
 }