Latest MCD-Level-2 Exam Questions

C.   

Create a Mule Plugin project
Create a common-global-error-handler flow inside the plugin project.
Use this plugin as a dependency in all Mule applications

Explanation:
To configure a common-global-handler flow that can be reused across all of the organization’s deployed applications, the developer should create a Mule Plugin project, create a common-global-error-handler flow inside the plugin project, and use this plugin as a dependency in all Mule applications. This way, the developer can import the common-global-error-handler flow in any application that needs it and avoid duplicating the error handling logic. 

References:
https://docs.mulesoft.com/mule-runtime/4.3/error-handling#global-error-handler

B.   

For persistent queues, the message will be processed after the system comes online

Explanation:
In case of a system failure, in-flight messages in persistent VM queues that have been consumed will be processed after the system comes online. This is because persistent VM queues store messages on disk and guarantee delivery even if there is a system crash or restart. Therefore, any in-flight messages that have been consumed but not processed will be recovered from disk and processed when the system is back online.

References:
https://docs.mulesoft.com/mule-runtime/4.3/vm-connector#persistent-queues

D.   

All operations are public

Explanation:
When using XML SDK for creating custom message processors, all operations are public by default and can be used by any Mule application that imports them. There is no way to make an operation private or protected in XML SDK.

References: https://docs.mulesoft.com/mule-sdk/1.1/xml-sdk#operations

C.   

Put the HTTP Request inside a try scope in Unit Successful.
In the error handler, use On Error Continue to catch permanent errors like HTTP UNAUTHORIZED.

Explanation:
To handle a permanent error response like HTTP:UNAUTHORIZED inside Until Successful, the developer should put the HTTP Request inside a try scope in Unit Successful, and use On Error Continue to catch permanent errors like HTTP UNAUTHORIZED in the error handler. This way, the developer can avoid retrying requests that will always fail due to a permanent error, and reduce latency. On Error Continue allows the flow to continue processing after handling the error.

References:
https://docs.mulesoft.com/mule-runtime/4.3/until-successful-scope
https://docs.mulesoft.com/mule-runtime/4.3/on-error-continue-concept

C.   

Time to live

The Cache scope supports time to live (TTL) as a cache invalidation strategy without having to write any additional code. TTL specifies how long the cached response is valid before it expires and needs to be refreshed. The Cache scope also supports custom invalidation strategies using MEL or DataWeave expressions.

References: https://docs.mulesoft.com/mule-runtime/4.3/cache-scope#cache_invalidation

C.   

The HTTP Listener generates correlation IDS unless a correlation ID is received in the HTTP request

Explanation:
When working with correlation IDs, the HTTP Listener generates correlation IDs unless a correlation ID is received in the HTTP request. In that case, it propagates the received correlation ID throughout the flow execution. Correlation IDs are used to track events across different flows or applications. 

References:
https://docs.mulesoft.com/mule-runtime/4.3/about-mule-message#message-attributes

B.   

Keytool-importkeystore –srckeystore keystore p12-srcstoretype JKS –destkeystore keystore.p12–deststoretype PKCS12

Explanation:
To convert a JKS keystore to PKCS12, the developer needs to use the keytool-importkeystore command with the following options: -srckeystore keystore.jks -srcstoretype JKS -destkeystore keystore.p12 -deststoretype PKCS12. This command imports all entries from a source JKS keystore (keystore.jks) into a destination PKCS12 keystore (keystore.p12).

References:
https://docs.oracle.com/en/java/javase/11/tools/keytool.html#GUID-5990A2E4-78E3-47B7-AE75-6D1826259549

D.   

NO action is needed as the correlation ID is returned to the caller in the response header by default

Explanation:
When implementing a synchronous API where the event source is an HTTP Listener, Mule automatically propagates some message attributes between flows via outbound and inbound properties. One of these attributes is correlation ID, which is returned to the caller in the response header by default as MULE_CORRELATION_ID. 

References:
https://docs.mulesoft.com/mule-runtime/4.3/about-mule-message#message-attributes

D.   

Add a Maven dependency in the POM file with jar as <classifier>

Explanation:
To include a common application as a reusable module in all API implementations, the developer should add a Maven dependency in the POM file with jar as <classifier>. This way, the developer can reuse Mule code from another application by packaging it as a JAR file and adding it as a dependency in the POM file of the API implementation. The classifier element specifies that it is a JAR file.

References:
https://docs.mulesoft.com/mule-runtime/4.3/mmp-concept#add-a-maven-dependency-to-the-pom-file

B.   

${secure::tiskeystore,keyPassowrd}

Explanation:
secure::tiskeystore,keyPassowrdShortExplanationofCorrectAnswerOnly:Toreferenceasecurepropertyvaluewithintheapplication,In this case, the property name is tiskeystore,keyPassword, so the correct syntax is ${secure::tiskeystore,keyPassowrd}. 

References:
https://docs.mulesoft.com/mule-runtime/4.3/secure-configuration-properties#referencing-secure-properties