[FAB-15823] Fix getStringPayload npe

getStringPayload will now return null if the payload is
null instead of throwing a null pointer exception

Also fixes build break introduced with new Context argument
on transaction methods

Change-Id: I15dc4403a7a4782de6a22da7885d4b5baf40e4d7
Signed-off-by: James Taylor <[email protected]>

Author: jt-nti

fabric-chaincode-shim/src/main/java/org/hyperledger/fabric/shim/Chaincode.java

@@ -6,11 +6,11 @@
 
 package org.hyperledger.fabric.shim;
 
+import static java.nio.charset.StandardCharsets.UTF_8;
+
 import java.util.HashMap;
 import java.util.Map;
 
-import static java.nio.charset.StandardCharsets.UTF_8;
-
 /**
  * Defines methods that all chaincodes must implement.
  */
@@ -70,7 +70,7 @@ public byte[] getPayload() {
         }
 
         public String getStringPayload() {
-            return new String(payload, UTF_8);
+            return (payload==null) ? null : new String(payload, UTF_8);
         }
 
         /**

fabric-chaincode-shim/src/test/java/contract/SampleContract.java

@@ -25,6 +25,13 @@ public class SampleContract implements ContractInterface {
     static public int t1Invoked = 0;
     static public int i1Invoked = 0;
 
+    @Transaction
+    public String t5(Context ctx) {
+        doSomeWork();
+        System.out.println("SampleContract::T5 Done");
+        return null;
+    }
+
     @Transaction(name = "t4")
     public String tFour(Context ctx) {
 

fabric-chaincode-shim/src/test/java/org/hyperledger/fabric/contract/ContractRouterTest.java

@@ -9,6 +9,7 @@
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
+import static org.hamcrest.Matchers.nullValue;
 import static org.hamcrest.Matchers.startsWith;
 import static org.junit.Assert.assertThat;
 
@@ -178,6 +179,32 @@ public void testInvokeTxnThatDoesNotExist() {
         assertThat(SampleContract.t1Invoked, is(0));
     }
 
+    @Test
+    public void testInvokeTxnThatReturnsNullString() {
+        ContractRouter r = new ContractRouter(new String[] { "-a", "127.0.0.1:7052", "-i", "testId" });
+        r.findAllContracts();
+        ChaincodeStub s = new ChaincodeStubNaiveImpl();
+
+        List<String> args = new ArrayList<>();
+        args.add("samplecontract:t5");
+        args.add("asdf");
+        ((ChaincodeStubNaiveImpl) s).setStringArgs(args);
+
+        SampleContract.beforeInvoked = 0;
+        SampleContract.afterInvoked = 0;
+        SampleContract.doWorkInvoked = 0;
+        SampleContract.t1Invoked = 0;
+
+        Chaincode.Response response = r.invoke(s);
+        assertThat(response, is(notNullValue()));
+        assertThat(response.getStatus(), is(Chaincode.Response.Status.SUCCESS));
+        assertThat(response.getStringPayload(), is(nullValue()));
+        assertThat(SampleContract.beforeInvoked, is(1));
+        assertThat(SampleContract.afterInvoked, is(1));
+        assertThat(SampleContract.doWorkInvoked, is(1));
+        assertThat(SampleContract.t1Invoked, is(0));
+    }
+
     @Test
     public void testInvokeTxnThatThrowsAnException() {
         ContractRouter r = new ContractRouter(new String[] { "-a", "127.0.0.1:7052", "-i", "testId" });

fabric-chaincode-shim/src/test/java/org/hyperledger/fabric/contract/routing/ContractDefinitionTest.java

@@ -12,6 +12,7 @@
 import java.lang.reflect.Method;
 import java.security.Permission;
 
+import org.hyperledger.fabric.contract.Context;
 import org.hyperledger.fabric.contract.ContractInterface;
 import org.hyperledger.fabric.contract.ContractRuntimeException;
 import org.hyperledger.fabric.contract.annotation.Contract;
@@ -89,7 +90,7 @@ public void duplicateTransaction() throws NoSuchMethodException, SecurityExcepti
         ContractDefinition cf = new ContractDefinitionImpl(SampleContract.class);
 
         ContractInterface contract = new SampleContract();
-        Method m = contract.getClass().getMethod("t2", new Class[] {});
+        Method m = contract.getClass().getMethod("t2", new Class[] { Context.class });
 
         thrown.expect(ContractRuntimeException.class);
         thrown.expectMessage("Duplicate transaction method t2");