MCD-Level-2 MuleSoft Certified Developer - Level 2 (Mule 4) Questions and Answers

To configure the Maven Resources plugin to exclude parsing binary files in the project’s src/main/resources/certs directory, option C should be used. This option specifies that any files with .cer or .jks extensions under the certs directory should be excluded from filtering. Filtering is a process of replacing placeholders with actual values in resource files during the build process. Binary files should not be filtered because they may become corrupted or unusable. References: https://maven.apache.org/plugins/maven-resources-plugin/examples/filter.html https://maven.apache.org/plugins/maven-resources-plugin/examples/include-exclude.html

To create a new project that selects the correct API version and scaffolds the flows from the API specification, the developer should import a published API. This option allows importing an API specification that has been published to Anypoint Exchange or Design Center, and selecting a specific version of that API specification. The developer can also choose to scaffold flows based on that API specification. References: https://docs.mulesoft.com/apikit/4.x/apikit-4-new-project-task

The result of accessing route C failure is Error,errorMessage,payload.failures[‘2’]. This is because a scatter-gather router returns an aggregated message that contains an array of results from each route and an array of failures from each route. The failures array contains error objects with information about each failed route execution. To access route C failure, which is the third route (index 2), the developer needs to use Error.errorMessage.payload.failures[‘2’] expression. References: https://docs.mulesoft.com/mule-runtime/4.3/scatter-gather-reference#scatter-gather-output

Based on the configuration below, when a HTTP request arrives at the Mule application’s endpoint, the execution order will be A1, B1, F1, B2, A2. This is because policies are executed before and after the API implementation flow according to their order attribute. Policy A has order 1, which means it is executed first before Policy B, which has order 2. The flow is executed after both policies are executed before the flow. Then, Policy B is executed after the flow before Policy A is executed after the flow. References: https://docs.mulesoft.com/api-manager/2.x/policies-policy-order

A web API can use HTTP Webhook to notify its client of state changes as soon as they occur. A webhook is an HTTP callback that allows an API to send real-time notifications to another system or application when an event happens. The client registers a URL with the API where it wants to receive notifications, and then the API sends an HTTP request to that URL with information about the event. References: https://docs.mulesoft.com/connectors/webhook/webhook-connector

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

To test that the payment API is working in production, the developer should create a health check endpoint that listens on a separate port and uses a separate HTTP Listener configuration from the API. This way, the developer can isolate the health check endpoint from the API traffic and avoid affecting the performance or availability of the API. The health check endpoint should return a simple response that indicates the status of the API, such as OK or ERROR. References: https://docs.mulesoft.com/api-functional-monitoring/afm-create-monitor#create-a-monitor

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

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

To invoke Bioinfo System API using its REST Connector, option E should be added to the pom.xml file. This option adds a dependency for Bioinfo System API REST Connector with its group ID, artifact ID, version, classifier, and type. The classifier specifies that it is a REST Connector (raml-client), and the type specifies that it is a Mule plugin (mule-plugin). References: https://docs.mulesoft.com/apikit/4.x/apikit-4-generate-from-rest-api-task#add-the-api-dependency-to-the-pom-file

The MuleSoft recommended method to encrypt sensitive property data is to use the Secure Properties Tool that comes with Anypoint Studio. This tool allows encrypting properties files with a secret key and then decrypting them at runtime using the same key. The encryption key and sensitive data should be different for each environment to ensure security and avoid accidental exposure of sensitive data. References: https://docs.mulesoft.com/mule-runtime/4.3/secure-configuration-properties

To develop an API that retrieves data from a hospital system using reusable Java libraries, the developer should install libraries in a local repository and refer to it in the pom.xml file. This way, the developer can use Maven to manage dependencies and invoke Java code from Mule applications using Java Module operations. References: https://docs.mulesoft.com/mule-runtime/4.3/java-module-reference#add-the-java-module-to-your-project https://docs.mulesoft.com/mule-runtime/4.3/java-module-reference#invoke-java-code

To ensure idempotent behavior within a Mule flow that contains a subflow with a Scatter-Gather scope, the developer should ensure an error-handling flow performs corrective actions to roll back all changes if any leg of the Scatter-Gather fails. Idempotency means that multiple identical requests have the same effect as a single request. Therefore, if one of the HTTP requests inside the Scatter-Gather fails, the error-handling flow should undo any changes made by other successful requests to ensure consistency and avoid partial updates. References: https://docs.mulesoft.com/mule-runtime/4.3/scatter-gather-concept https://docs.mulesoft.com/mule-runtime/4.3/error-handling

To use the OAuth 2.0 Authorization Code grant type for authentication, the HTTP Connector configuration requires the following properties: token URL, authorization URL, client ID, client secret, and local callback URL. The token URL is the endpoint of the authorization server that provides access tokens. The authorization URL is the endpoint of the authorization server that initiates the user consent flow. The client ID and client secret are the credentials of the Mule application registered with the authorization server. The local callback URL is the endpoint of the Mule application that receives the authorization code from the authorization server. References: https://docs.mulesoft.com/http-connector/1.6/http-authentication#oauth-2-0

The http-policy:processor element is used to intercept outbound HTTP requests made by Mule applications. It allows customizing the request before it is sent to the target API and modifying the response after it is received from the target API. References: https://docs.mulesoft.com/api-manager/2.x/policy-mule4-custom-policy#policy-xml-file