Write integration tests

This tutorial guides you through writing integration tests for your CorDapp. Integration tests allow you to test all features of your CorDapp together.

You will be creating your integration tests in this directory: workflows/src/test/java/com/tutorial/

Learning objectives

After you’ve completed this tutorial, you will be able to write integration tests for your CorDapp.

Before you start

Before you start writing your own unit tests:

• Read the API: Testing documentation.
• Download TemplateInitiator.java and TemplateContract.java from the CorDapp tutorial repository.
• Move TemplateState.java into your com.tutorial package.

Write the CreateAndIssueAppleStamp integration test

When writing flow unit tests, you rely on both states and contracts to test the functionality of the flow. You also must create a MockNetwork with StartedMockNodes. StartedMockNodes behave like normal Corda nodes, but their services are mocked out.

Flow tests are generally more complicated, so R3 recommends having a file for each flow you wish to test.

Follow these steps to write a flow unit test for the CreateAndIssueAppleStampTest:

Add the MockNetwork and StartedMockNodes

1. Create a file called CreateAndIssueAppleStampTest.
2. Add the CreateAndIssueAppleStampTest public class.
3. Add the private MockNetwork and a network name.
4. Add two private StartedMockNodes named a and b.

So far, your code should look like this:

package com.tutorial;

import net.corda.testing.node.MockNetwork;
import net.corda.testing.node.StartedMockNode;

public class CreateAndIssueAppleStampTest {
    private MockNetwork network;
    private StartedMockNode a;
    private StartedMockNode b;

Add the CorDapp details

Next you must indicate where your CorDapp is so that the test engine can run:

1. Add a @Before annotation to indicate that this is what must happen before the test is run.
2. Add a public void setup including the new MockNetwork and new MockNetworkParameters. Use withCordappsForAllNodes to reference the CorDapp.
3. Add the function TestCorDapp.findCordapp to find the contracts and flows JARs (com.tutorial.contracts and com.tutorial.flows, respectively).
4. Create an a and b node using createPartyNode. Use null for the legalName of the node to use the default.
5. Add the runNetwork command to start the MockNetwork.

So far, your code should look like this:

package com.tutorial;

import com.google.common.collect.ImmutableList;
import net.corda.testing.node.MockNetwork;
import net.corda.testing.node.MockNetworkParameters;
import net.corda.testing.node.StartedMockNode;
import net.corda.testing.node.TestCordapp;
import org.junit.Before;

public class CreateAndIssueAppleStampTest {
    private MockNetwork network;
    private StartedMockNode a;
    private StartedMockNode b;

    @Before
    public void setup() {
        network = new MockNetwork(new MockNetworkParameters().withCordappsForAllNodes(ImmutableList.of(
                TestCordapp.findCordapp("com.tutorial.contracts"),
                TestCordapp.findCordapp("com.tutorial.flows"))));
        a = network.createPartyNode(null);
        b = network.createPartyNode(null);
        network.runNetwork();
    }

Add an @After annotation and steps to tear down the network

After your test has run, you will want the network to be torn down to free up resources on your machine.

1. Add an @After annotation.
2. Add a tearDown method.
3. Inside the method, add stopNodes command to stop the nodes on the network.

Add the test content

Now that you’ve added steps for before and after, you can finally add the content that will test your CreateAndIssueAppleStamp flow.

1. Add the @Test annotation.
2. Add a public void with the CreateAndIssueAppleStampTest.
3. Reference the flow that is being tested to create the test flow. Here you should reference both the parent class of the flow (CreateAndIssueAppleStamp) and the initiating subflow (CreateAndIssueAppleStampInitiator). Call this flow1 in your test.
4. Add the stampDescription from your initiating flow with sample content - for example, stampDescription: "Honey Crisp 4072".
5. Reference the b node that you added in your MockNetwork using getInfo, getLegalIdentities, and get(0) methods. This will return a party, completing the constructor.
6. You need a node to run the test flow you just created. Use node a and the startFlow command to start flow1.
7. Add a runNetwork command to start the network and test the flow.

Add QueryCriteria

To verify that the flow test has run and the flow works, you must query the database of one of the StartedMockNodes to see if the transaction was successfully stored. Since a initiated the flow, you must check the database of node b to ensure that the state was successfully issued to them.

1. Create a query with VaultQueryCriteria.
2. In the VaultQueryCriteria, look for a status of UNCONSUMED using the withStatus method.
3. Add your query for the AppleStamp state. Use the getServices and getVaultService methods to query node b’s vault.
4. Return a list of states with getStates, then return the reference of the first of these states with get(0). Return getState to get the state, then getData to extract the data from the state. This gives you an AppleStamp object.
5. assert this AppleStamp object to verify that the stampDesc matches the example content you entered (Honey Crisp 4072).

After you have finished writing the query, your flow test is finished and your code should look like this:

package com.tutorial;

import com.google.common.collect.ImmutableList;
import com.tutorial.flows.CreateAndIssueAppleStamp;
import com.tutorial.flows.TemplateInitiator;
import com.tutorial.states.AppleStamp;
import com.tutorial.states.TemplateState;
import net.corda.core.node.services.Vault;
import net.corda.core.node.services.vault.QueryCriteria;
import net.corda.core.transactions.SignedTransaction;
import net.corda.testing.node.MockNetwork;
import net.corda.testing.node.MockNetworkParameters;
import net.corda.testing.node.StartedMockNode;
import net.corda.testing.node.TestCordapp;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.util.concurrent.Future;

public class CreateAndIssueAppleStampTest {
    private MockNetwork network;
    private StartedMockNode a;
    private StartedMockNode b;

    @Before
    public void setup() {
        network = new MockNetwork(new MockNetworkParameters().withCordappsForAllNodes(ImmutableList.of(
                TestCordapp.findCordapp("com.tutorial.contracts"),
                TestCordapp.findCordapp("com.tutorial.flows"))));
        a = network.createPartyNode(null);
        b = network.createPartyNode(null);
        network.runNetwork();
    }

    @After
    public void tearDown() {
        network.stopNodes();
    }

    @Test
    public void dummyTest() {
        TemplateInitiator flow = new TemplateInitiator(b.getInfo().getLegalIdentities().get(0));
        Future<SignedTransaction> future = a.startFlow(flow);
        network.runNetwork();

        //successful query means the state is stored at node b's vault. Flow went through.
        QueryCriteria inputCriteria = new QueryCriteria.VaultQueryCriteria().withStatus(Vault.StateStatus.UNCONSUMED);
        TemplateState state = b.getServices().getVaultService()
                .queryBy(TemplateState.class,inputCriteria).getStates().get(0).getState().getData();
    }

    @Test
    public void CreateAndIssueAppleStampTest(){
        CreateAndIssueAppleStamp.CreateAndIssueAppleStampInitiator flow1 =
                new CreateAndIssueAppleStamp.CreateAndIssueAppleStampInitiator(
                        "HoneyCrispy 4072",this.b.getInfo().getLegalIdentities().get(0));
        Future<SignedTransaction> future1 = a.startFlow(flow1);
        network.runNetwork();

        //successful query means the state is stored at node b's vault. Flow went through.
        QueryCriteria inputCriteria = new QueryCriteria.VaultQueryCriteria()
                .withStatus(Vault.StateStatus.UNCONSUMED);
        AppleStamp state = b.getServices().getVaultService()
                .queryBy(AppleStamp.class,inputCriteria).getStates().get(0).getState().getData();
        assert(state.getStampDesc().equals("HoneyCrispy 4072"));
    }




}

Take a look at the Apple Stamp CorDapp solution to see the implementation of integration tests for the RedeemApples flow and the PackageApples flow.