Pass the Salesforce Salesforce MuleSoft MuleSoft-Integration-Architect-I Questions and answers with CertsForce

Explanation

Correct answer is Database polling continues Only HTTP requests sent to the remaining node continue to be accepted. Explanation : Architecture descripted in the question could be described as follows.When node 1 is down , DB polling will still continue via node 2 . Also requests which are coming directly to node 2 will also be accepted and processed in BAU fashion. Only thing that wont work is when requests are sent to Node 1 HTTP connector. The flaw with this architecture is HTTP clients are sending HTTP requests directly to individual cluster nodes. By default, clustering Mule runtime engines ensures high system availability. If a Mule runtime engine node becomes unavailable due to failure or planned downtime, another node in the cluster can assume the workload and continue to process existing events and messages

Diagram Description automatically generated

Explanation

CloudHub object store should be in same region where the Mule application is deployed. This will give optimal performance.

Before learning about Cache scope and object store in Mule 4 we understand what is in general Caching is and other related things.

WHAT DOES “CACHING” MEAN?

Caching is the process of storing frequently used data in memory, file system or database which saves processing time and load if it would have to be accessed from original source location every time.

In computing, a cache is a high-speed data storage layer which stores a subset of data, so that future requests for that data are served up faster than is possible by accessing the data’s primary storage location. Caching allows you to efficiently reuse previously retrieved or computed data.

How does Caching work?

The data in a cache is generally stored in fast access hardware such as RAM (Random-access memory) and may also be used in correlation with a software component. A cache’s primary purpose is to increase data retrieval performance by reducing the need to access the underlying slower storage layer.

Caching in MULE 4

In Mule 4 caching can be achieved in mule using cache scope and/or object-store. Cache scope internally uses Object Store to store the data.

What is Object Store

Object Store lets applications store data and states across batch processes, Mule components, and applications, from within an application. If used on cloud hub, the object store is shared between applications deployed on Cluster.

Cache Scope is used in below-mentioned cases:

● Need to store the whole response from the outbound processor

● Data returned from the outbound processor does not change very frequently

● As Cache scope internally handle the cache hit and cache miss scenarios it is more readable

Object Store is used in below-mentioned cases:

● Need to store custom/intermediary data

● To store watermarks

● Sharing the data/stage across applications, schedulers, batch.

If CloudHub object store is in same region where the Mule application is deployed it will aid in fast access of data and give optimal performance.

When migrating from an on-premises cluster to a Runtime Fabric (RTF) cluster, and needing to enable Mule applications to store and share data across application replicas and restarts, the use of Anypoint Object Store V2 is the most suitable option. Here’s why and how to implement it:

Understanding Object Store V2:

Object Store V2 is designed to store and retrieve key-value pairs in a scalable and highly available manner. It is particularly useful for sharing state and data between different instances of applications running on RTF.

Setting Up Anypoint Object Store V2:

First, ensure that your MuleSoft Anypoint Platform account has access to Object Store V2.

Configure your Mule application to use Object Store V2 by defining an object store in your Mule configuration file. This can be done using the objectstore element in your Mule flow.

Configuration Steps:

Add the Object Store connector to your Mule project.

Define the object store configuration in your Mule flow as follows:

xml

Use the object store in your flows to store and retrieve data:

xml

Deploying on RTF:

Deploy your Mule application to the RTF cluster. The RTF will handle scaling and ensure that the Object Store V2 is available to all instances of your application.

Benefits:

Object Store V2 ensures data is shared and persisted across different application replicas and restarts, which meets the requirement of storing and sharing data across application replicas in the RTF cluster.

Anypoint Platform offers universal API management and Integration-Platform-as-a-Service (iPaaS) capabilities in a unified platform, meaning that it provides a single control plane to manage both full-lifecycle API management and integration. This allows organizations to easily manage their APIs and integrations, as well as deploy APIs and integrations quickly and efficiently. According to the MuleSoft Certified Integration Architect - Level 1 Course Book, “Anypoint Platform provides a unified platform for managing, deploying, and monitoring both API and integration solutions, allowing organizations to quickly and easily build and manage their APIs and integrations.”

The Salesforce API used to deploy, retrieve, create, update, or delete customization information, such as custom object definitions, using Mule Salesforce Connectors in a Mule application, is the Metadata API. The Metadata API enables programmatic access to the metadata of Salesforce organizations, allowing developers to manage customizations and configurations programmatically.

Using the Metadata API, Mule applications can automate the deployment and management of Salesforce customizations, facilitating continuous integration and deployment processes within Salesforce environments.

References

MuleSoft Documentation on Salesforce Connectors

Salesforce Metadata API Developer Guide

Explanation

● Option A says "Perform EACH DB insert in a SEPARATE DB transaction". In this case if first DB insert is successful and second one fails then first insert won't be rolled back causing inconsistency. This option is ruled out.

● Option D says Perform BOTH DB inserts in ONE DB transaction.

Rule of thumb is when one or more DB connections are required we must use XA transaction as local transactions support only one resource. So this option is also ruled out.

● Option B acknowledges the before DB processing, so message is removed from the queue. In case of system failure at later point, message can't be retrieved.

● Option C is Valid: Though it says "do not ack JMS message", message will be auto acknowledged at the end of transaction. Here is how we can ensure all components are part of XA transaction: https://docs.mulesoft.com/jms-connector/1.7/jms-transactions

Additional Information about transactions:

● XA Transactions - You can use an XA transaction to group together a series of operations from multiple transactional resources, such as JMS, VM or JDBC resources, into a single, very reliable, global transaction.

● The XA (eXtended Architecture) standard is an X/Open group standard which specifies the interface between a global transaction manager and local transactional resource managers.

The XA protocol defines a 2-phase commit protocol which can be used to more reliably coordinate and sequence a series of "all or nothing" operations across multiple servers, even servers of different types

● Use JMS ack if

– Acknowledgment should occur eventually, perhaps asynchronously

– The performance of the message receipt is paramount

– The message processing is idempotent

– For the choreography portion of the SAGA pattern

● Use JMS transactions

– For all other times in the integration you want to perform an atomic unit of work

– When the unit of work comprises more than the receipt of a single message

– To simply and unify the programming model (begin/commit/rollback)

In a microservices application architecture, each service is designed to be an independent deployment artifact. This means that services can be deployed, updated, and scaled independently of one another. This characteristic allows for greater flexibility and agility in managing applications, as individual services can be scaled up or down based on demand without impacting other services. It also enhances fault isolation, as issues in one service do not necessarily affect the entire application.

This is in contrast to monolithic architectures, where all components are packaged and deployed together, often resulting in a single point of failure and difficulties in scaling and updating specific parts of the application.

References

MuleSoft Documentation on Microservices Architecture

Principles of Microservices Design

JMS (Java Message Service): JMS is a robust messaging standard that supports reliable and asynchronous communication. It allows message producers and consumers to exchange messages via a common message broker.

Transactions with Automatic Acknowledgements: Utilizing JMS transactions ensures that messages are processed reliably. The automatic acknowledgement mode means that once the consumer receives the message, it acknowledges the broker automatically, ensuring that no messages are lost.

Performance and Reliability: JMS transactions offer both high performance and reliability. By enabling transactions, each message processing step can be committed or rolled back, ensuring data integrity.

Cross-Cluster Messaging: For a stock trading company dealing with millions of trades, using JMS transactions allows for consistent and reliable message delivery across different clusters in their network. This approach is more suitable compared to non-transactional or VM queues due to the scale and reliability requirements.

Event-Driven APIs: The APIs can leverage the transactional nature of JMS to ensure that messages exchanged between different services are reliable and can recover gracefully from failures.

When a RAML definition is updated and a new version is published to Anypoint Exchange, the client applications that consume the API need to be updated to utilize the new operations. Here’s how the Mule application team can achieve this:

Access Anypoint Exchange:

Go to Anypoint Exchange and find the updated RAML definition of the API.

Update the REST Connector:

In the Mule application, locate the existing REST connector that was generated from the previous version of the API.

Update this connector to the latest version by reimporting the RAML definition.

This can be done via the Anypoint Studio by navigating to the Mule Palette, finding the REST connector, and updating it with the new RAML.

Regenerate Client Code (If Necessary):

Sometimes, updating the connector may require regenerating the client code to include new operations.

Ensure that all new methods and endpoints are available in your Mule application after the update.

Test New Operations:

Incorporate and test the new operations in the Mule application to ensure they function correctly with the updated API implementation.

References

MuleSoft Documentation: API Development

Anypoint Studio Documentation: Using Connectors