WSO2 unit testing Mock Service is not working - wso2

Question

I`m using the 2SO2 integration studio version is 8.0.0.
I tried to write junit suite test for my app using mock-service for my endpoint.
But when I tried to run the test I got the next failed :
My mock-service is set up with port = 9090 ( i do not know it`s right or not, this port i found in documentation by wso2 : https://ei.docs.wso2.com/en/7.2.0/micro-integrator/develop/creating-unit-test-suite/):
Test is :
<unit-test>
<artifacts>
<test-artifact>
<artifact>/LmaAPIConfigs/src/main/synapse-config/api/LmaAPI.xml</artifact>
</test-artifact>
<supportive-artifacts/>
<registry-resources/>
<connector-resources/>
</artifacts>
<test-cases>
<test-case name="TestMock">
<input>
<request-path>/currency</request-path>
<request-method>POST</request-method>
<request-protocol>http</request-protocol>
<payload><![CDATA[{"currency": "USD"}]]></payload>
<properties>
<property name="Content-Type" scope="transport" value="application/json"/>
</properties>
</input>
<assertions>
<assertEquals>
<actual>$body</actual>
<expected><![CDATA[<jsonObject><r030>840</r030><txt>Долар США</txt><rate>36.5686</rate><cc>USD</cc><exchangedate>]]></expected>
<message>not equals</message>
</assertEquals>
<assertNotNull>
<actual>$body</actual>
<message>body is null</message>
</assertNotNull>
</assertions>
</test-case>
</test-cases>
<mock-services>
<mock-service>/LmaAPI/LmaAPIConfigs/test/resources/mock-services/Exchange.xml</mock-service>
</mock-services>
</unit-test>
The logs from wso2carbon.log file :
[2022-09-19 08:49:43,467] INFO {org.apache.synapse.unittest.UnitTestingExecutor} - Start processing test-case handler
[2022-09-19 08:49:43,467] INFO {org.apache.synapse.unittest.UnitTestingExecutor} - Unit testing agent checks transport Pass-through HTTP Listener port
[2022-09-19 08:49:43,487] INFO {org.apache.synapse.transport.passthru.core.PassThroughListeningIOReactorManager} - Pass-through EI_INTERNAL_HTTPS_INBOUND_ENDPOINT Listener started on 0:0:0:0:0:0:0:0:9164
[2022-09-19 08:49:43,495] INFO {org.apache.synapse.unittest.SynapseTestcaseDataReader} - Artifact data from descriptor data read successfully
[2022-09-19 08:49:43,495] INFO {org.apache.synapse.unittest.SynapseTestcaseDataReader} - Test case data from descriptor data read successfully
[2022-09-19 08:49:43,497] INFO {org.apache.synapse.unittest.SynapseTestcaseDataReader} - Mock service data from descriptor data read successfully
[2022-09-19 08:49:43,498] INFO {org.apache.synapse.unittest.ConfigModifier} - Mock service creator ready to start service for Exchange
[2022-09-19 08:49:43,530] INFO {org.apache.synapse.unittest.MockServiceCreator} - Mock service started for Exchange in - http://localhost:9090/get-nbu-exchange
[2022-09-19 08:49:43,530] INFO {org.apache.synapse.unittest.ConfigModifier} - Thread waiting for mock service(s) starting
[2022-09-19 08:49:43,609] ERROR {org.apache.synapse.unittest.UnitTestingExecutor} - Failed to get input stream from TCP connection java.io.EOFException
at java.base/java.io.ObjectInputStream$PeekInputStream.readFully(ObjectInputStream.java:2842)
at java.base/java.io.ObjectInputStream$BlockDataInputStream.readShort(ObjectInputStream.java:3337)
at java.base/java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:925)
at java.base/java.io.ObjectInputStream.<init>(ObjectInputStream.java:368)
at org.apache.synapse.unittest.RequestHandler.readData(RequestHandler.java:112)
at org.apache.synapse.unittest.RequestHandler.run(RequestHandler.java:74)
at java.base/java.lang.Thread.run(Thread.java:834)
[2022-09-19 08:49:43,609] ERROR {org.apache.synapse.unittest.UnitTestingExecutor} - Error while reading data from received message java.lang.NullPointerException
at org.apache.synapse.unittest.SynapseTestcaseDataReader.readAndStoreArtifactData(SynapseTestcaseDataReader.java:148)
at org.apache.synapse.unittest.RequestHandler.preProcessingData(RequestHandler.java:137)
at org.apache.synapse.unittest.RequestHandler.run(RequestHandler.java:80)
at java.base/java.lang.Thread.run(Thread.java:834)
[2022-09-19 08:49:43,609] ERROR {org.apache.synapse.unittest.UnitTestingExecutor} - Reading Synapse testcase data failed
[2022-09-19 08:49:43,609] ERROR {org.apache.synapse.unittest.UnitTestingExecutor} - Error while running client request in test agent java.net.SocketException: Software caused connection abort: socket write error
at java.base/java.net.SocketOutputStream.socketWrite0(Native Method)
at java.base/java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:110)
at java.base/java.net.SocketOutputStream.write(SocketOutputStream.java:150)
at java.base/java.io.ObjectOutputStream$BlockDataOutputStream.drain(ObjectOutputStream.java:1883)
at java.base/java.io.ObjectOutputStream$BlockDataOutputStream.setBlockDataMode(ObjectOutputStream.java:1792)
at java.base/java.io.ObjectOutputStream.writeNonProxyDesc(ObjectOutputStream.java:1287)
at java.base/java.io.ObjectOutputStream.writeClassDesc(ObjectOutputStream.java:1232)
at java.base/java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1428)
at java.base/java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1179)
at java.base/java.io.ObjectOutputStream.writeFatalException(ObjectOutputStream.java:1583)
at java.base/java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:352)
at org.apache.synapse.unittest.RequestHandler.writeData(RequestHandler.java:238)
at org.apache.synapse.unittest.RequestHandler.run(RequestHandler.java:92)
at java.base/java.lang.Thread.run(Thread.java:834)
[2022-09-19 08:49:43,830] INFO {io.netty.handler.logging.LoggingHandler} - [id: 0x00a2ce58] REGISTERED
[2022-09-19 08:49:43,830] INFO {io.netty.handler.logging.LoggingHandler} - [id: 0x00a2ce58] BIND: localhost/127.0.0.1:9090
[2022-09-19 08:49:43,830] INFO {io.netty.handler.logging.LoggingHandler} - [id: 0x00a2ce58, L:/127.0.0.1:9090] ACTIVE
[2022-09-19 08:49:44,040] INFO {org.apache.synapse.unittest.ConfigModifier} - Mock service(s) are started with given ports
[2022-09-19 08:49:44,042] INFO {org.apache.synapse.unittest.UnitTestingExecutor} - Main test artifact deployment started
[2022-09-19 08:49:44,042] INFO {io.netty.handler.logging.LoggingHandler} - [id: 0x00a2ce58, L:/127.0.0.1:9090] READ: [id: 0x7fabaabd, L:/127.0.0.1:9090 - R:/127.0.0.1:61051]
[2022-09-19 08:49:44,042] INFO {io.netty.handler.logging.LoggingHandler} - [id: 0x00a2ce58, L:/127.0.0.1:9090] READ COMPLETE
[2022-09-19 08:49:44,326] INFO {org.apache.synapse.api.API} - {api:LmaAPI} Initializing API: LmaAPI
[2022-09-19 08:49:44,326] INFO {org.apache.synapse.core.axis2.Axis2SynapseEnvironment} - Continuation call is set to true
[2022-09-19 08:49:44,326] INFO {org.apache.synapse.deployers.APIDeployer} - API named 'LmaAPI' has been deployed from file : LmaAPI
[2022-09-19 08:49:44,326] INFO {org.apache.synapse.unittest.TestingAgent} - Primary test API artifact deployed successfully
[2022-09-19 08:49:44,326] INFO {org.apache.synapse.unittest.UnitTestingExecutor} - Synapse testing agent ready to mediate test cases through deployments
[2022-09-19 08:49:44,326] INFO {org.apache.synapse.unittest.TestingAgent} - 1 Test case(s) ready to execute
[2022-09-19 08:49:44,326] INFO {org.apache.synapse.unittest.UnitTestingExecutor} - Invoking URI - http://localhost:8290/lma/currency
[2022-09-19 08:49:44,467] INFO {org.apache.synapse.mediators.builtin.LogMediator} - {api:LmaAPI} uri.var.currency = USD
[2022-09-19 08:49:44,472] INFO {org.apache.synapse.mediators.builtin.LogMediator} - {api:LmaAPI} To: /lma/currency, MessageID: urn:uuid:898e7062-97b1-4179-a6d0-a3a63106455f, correlation_id: 898e7062-97b1-4179-a6d0-a3a63106455f, Direction: request, LmaAPI_currency = ERROR RESPONSE, Payload: {"currency": "USD"}
[2022-09-19 08:49:44,498] INFO {org.apache.synapse.unittest.Assertor} - Assert Equals - assert property for services started
[2022-09-19 08:49:44,514] INFO {org.apache.synapse.unittest.Assertor} - Service Assert Expression - $body
[2022-09-19 08:49:44,514] INFO {org.apache.synapse.unittest.Assertor} - Service mediated result for Actual - <jsonObject><currency>USD</currency></jsonObject>
[2022-09-19 08:49:44,514] INFO {org.apache.synapse.unittest.Assertor} - Service Assert Expected - <jsonObject><r030>840</r030><txt>ДоларСША</txt><rate>36.5686</rate><cc>USD</cc></jsonObject>
[2022-09-19 08:49:44,514] ERROR {org.apache.synapse.unittest.Assertor} - Service assertEquals for $body expression failed with a message - not equals
[2022-09-19 08:49:44,514] ERROR {org.apache.synapse.unittest.Assertor} - Unit testing failed for the test case - TestMock
[2022-09-19 08:49:44,514] INFO {org.apache.synapse.deployers.APIDeployer} - API named 'LmaAPI' has been undeployed
[2022-09-19 08:49:44,514] INFO {org.apache.synapse.api.API} - {api:LmaAPI} Destroying API: LmaAPI
[2022-09-19 08:49:44,514] INFO {org.apache.synapse.core.axis2.Axis2SynapseEnvironment} - Continuation call is set to false
[2022-09-19 08:49:44,514] INFO {org.apache.synapse.unittest.TestingAgent} - Undeployed all the deployed test and supportive artifacts
[2022-09-19 08:49:44,514] INFO {io.netty.handler.logging.LoggingHandler} - [id: 0x00a2ce58, L:/127.0.0.1:9090] INACTIVE
[2022-09-19 08:49:44,514] INFO {io.netty.handler.logging.LoggingHandler} - [id: 0x00a2ce58, L:/127.0.0.1:9090] UNREGISTERED
[2022-09-19 08:49:44,521] INFO {org.apache.synapse.commons.emulator.core.Emulator} - Emulator shutdown successfully.......
[2022-09-19 08:49:44,521] INFO {org.apache.synapse.unittest.UnitTestingExecutor} - End processing test-case handler
My synapse artefacts :
My API :
My EP :

Answer 1

Mock Service port is simply a port you want your Mock service to start on, this can be any arbitrary port that is not occupied by any other service. So in your case, if any other service is not using the port 9090 you can use this. As you can see here in the code, a new Emulator will be started with this port and the context you are providing to facilitate mocking.
When you create a Mock service, you will be mocking an Endpoint. So I assume you already have an Endpoint Defined, and trying to mock this. If that's the case you need to add that Endpoint to the <supportive-artifacts/> section, in your Test Suite. Something like the below.
<supportive-artifacts>
<artifact>PATH_TO_ENDPOINT</artifact>
</supportive-artifacts>
I'm not exactly sure why you are getting a Received status code - 202 as the response. But it typically means your integration is unable to run.(Probably due to the missing endpoint). Also, it's important to note that all the detailed logs will be logged on the server side. So you won't be able to figure out what's happening by just looking at the Maven log. For example, as you can see here the server should log a message when your mock service is started. So make sure you check the server-side logs to identify any issues. If you are just executing from Integration Studio, the logs are located at <INTEGRATION_STUDIO_HOME>/runtime/microesb/repository/logs/wso2carbon.log

Answer 2

Integration Studio 8.0.0 was having some bugs related to the unit testing and mock services. AFAIK the issue you observed (Receiving a 202 status code) and the one #ycr have mentioned (Missing endpoint config in the <supportive-artifacts/> [1]) have been fixed in the latest Integration Studio 8.1.0.
Can you try this in the latest updated Integration Studio 8.1.0 pack? You can download the latest version from the official website. Please refer Get the latest updates to install the latest updates to Integration Studio.