Unit test testGetWithoutTid in CorrelationHandlerTest is order dependent

[SaaiVenkat]

Issue

• In com.networknt.correlation.CorrelationHandlerTest, if testGetWithoutTid() is run after testGetWithoutTidNoAutogen(), we face the following issue

java.lang.AssertionError: 
Expected :200
Actual   :500
	at org.junit.Assert.fail(Assert.java:89)
	at org.junit.Assert.failNotEquals(Assert.java:835)
	at org.junit.Assert.assertEquals(Assert.java:647)
	at org.junit.Assert.assertEquals(Assert.java:633)
	at com.networknt.correlation.CorrelationHandlerTest.test02_testGetWithoutTid(CorrelationHandlerTest.java:158)

• Since JUnit 4 doesn't guarantee the order of test executions by default, JUnit could execute testGetWithoutTid() after testGetWithoutTidNoAutogen() resulting in the above error.

Root Cause

• The test testGetWithoutTidNoAutogen() sets the autogenCorrelationID to false at

  light-4j/correlation/src/test/java/com/networknt/correlation/CorrelationHandlerTest.java

  Line 159 in 7152f18

  CorrelationHandler.config.setAutogenCorrelationID(false);

• When the test testGetWithoutTid() is run after the above step, the following code is not executed because of the polluted autogenCorrelationID
  

  light-4j/correlation/src/main/java/com/networknt/correlation/CorrelationHandler.java

  Lines 68 to 75 in 7152f18

  	if(config.isAutogenCorrelationID()) {
  	// generate a UUID and put it into the request header
  	cId = Util.getUUID();
  	exchange.getRequestHeaders().put(HttpStringConstants.CORRELATION_ID, cId);
  	String tId = exchange.getRequestHeaders().getFirst(HttpStringConstants.TRACEABILITY_ID);
  	if(tId != null && logger.isInfoEnabled()) {
  	logger.info("Associate traceability Id " + tId + " with correlation Id " + cId);
  	}

• Since the UUID is not generated and not set in the request handler, the request given from the test testGetWithoutTid() results in a 5xx server error

Proposed Solution

• Resetting the CorrelationHandler.config to default value before each test run will ensure that the unit tests are run with the correct config value
• This can be done by setting the configuration to its default value through CorrelationHandler.config.setAutogenCorrelationID(true); after the test testGetWithoutTidNoAutogen() is executed