MCD - Level 2: MuleSoft Certified Developer - Level 2 (Mule 4)

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.

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

The result of the Mule Maven Plugin configuration of the value of property its,keystorePassword in CloudHub 2.0 is that Runtime Manager masks the value. This means that Runtime Manager hides or obscures the value from anyone who views it in Runtime Manager or Anypoint Platform.

Reference: https://docs.mulesoft.com/runtime-manager/runtime-manager-agent-for-mule4#properties-tab

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.

Reference: https://docs.mulesoft.com/api-manager/2.x/policy-mule4-custom-policy#policy-xml-file

To achieve a publish/subscribe model using Anypoint MQ, where each system receives the same gate change notification event, the developer should publish the gate change notification to an Anypoint MQ exchange, create different Anypoint MQ queues meant for each of the other subscribing systems, and bind the exchange with each of the queues. An exchange is a message routing agent that can send messages to different queues based on predefined criteria. By binding an exchange with multiple queues, each queue receives a copy of every message sent to that exchange. Therefore, each system can subscribe to its own queue and receive every gate change notification event.

Reference: https://docs.mulesoft.com/anypoint-mq/3.x/anypoint-mq-exchanges

To validate the data before posting to the target system, the developer should add the JSON module dependency and add the validate-schema operation in the flow, configured to reference the schema. The JSON module provides a validate-schema operation that validates a JSON payload against a JSON schema and throws an error if the payload is invalid.

Reference: https://docs.mulesoft.com/json-module/1.1/json-validate-schema

To implement a readiness endpoint to monitor all system APIs, the developer should create a dedicated endpoint that responds with the API status and reachability of the underlying systems. This way, the DevOps team can check if the system API is ready to receive requests and if it can communicate with its backend systems without errors.

Reference: https://docs.mulesoft.com/mule-runtime/4.3/deployment-strategies#readiness-probes

When an HTTP request is received and the HTTP Caching policy is applied first, it checks if there is a cached response for that request in Object Store. If there is a cache hit, meaning that a valid cached response exists, then only the HTTP Caching policy is evaluated and the cached response is returned to the caller without invoking the OAuth policy or the API implementation. If there is a cache miss, meaning that no valid cached response exists, then both the HTTP Caching policy and the OAuth policy are evaluated before invoking the API implementation.

Reference: https://docs.mulesoft.com/api-manager/2.x/http-caching-policy#policy-ordering

To reuse Mule Maven plugin configuration across multiple individual Mule applications, the developer should use a parent pom.xml file. A parent pom.xml file defines common configuration for one or more child projects that inherit from it. The developer can specify common properties and dependencies for all child projects in the parent pom.xml file, such as Mule Maven plugin configuration, and then reference them in each child project's pom.xml file using placeholders.

Reference: https://docs.mulesoft.com/mule-runtime/4.3/mmp-concept#parent-pom https://maven.apache.org/guides/introduction/introduction-to-the-pom.html#Project_Inheritance

The validate-customer flow uses an until-successful scope to validate each field of the customer data. The until-successful scope executes its processors until they succeed or exhausts the maximum number of retries. If any processor fails, it raises an error and stops executing the remaining processors. Therefore, if only the email address is invalid, a VALIDATION.INVALID_EMAIL error is raised and the validation of appointment date and customer name is skipped.

Reference: https://docs.mulesoft.com/mule-runtime/4.3/until-successful-scope