Expected Salesforce MuleSoft Developer I Exam Topics, as suggested by Salesforce :

• Module 1: Creating Application Networks: The topic of creating Application Networks encompasses understanding MuleSoft’s proposal for closing the IT delivery gap and describing the role and characteristics of the modern API. It also includes the purpose and roles of a Center for Enablement (C4E), and the benefits of API-led.
• Module 2: Designing APIs: Designing APIs involves describing the lifecycle of the modern API and using RAML to define various aspects of an API. It includes identifying when to use query parameters vs URI parameters, and defining API parameters.
• Module 3: Accessing and Modifying Mule Events: It describes the Mule event data structure. Moreover, the topic focuses on usage of transformers and enriching Mule events.
• Module 4: Structuring Mule Applications: Structuring Mule applications covers parameterizing an application and defining and reusing global configurations. It includes breaking an application into multiple flows using private flows, subflows, and the Flow Reference component.
• Module 5: Building API Implementation Interfaces: This topic involves manually creating a RESTful interface for a Mule application and generating a REST Connector from a RAML specification. It also includes describing the features and benefits of APIkit.
• Module 6: Using Connectors: It focuses on retrieving data from REST services using HTTP Request or REST Connector. Moreover, the topic covers using a Web Service Consumer connector for SOAP web services and the Transform Message component.
• Module 7: Processing Records: Processing records includes methods for processing individual records in a collection and explaining how Mule events are processed by the For Each scope. It also involves using the Batch Job with Batch Steps and a Batch Aggregator.
• Module 8: Transforming Data with DataWeave: It involves writing DataWeave scripts and using DataWeave functions. This topic also includes defining and using DataWeave variables, functions, and modules, and applying correct syntax.
• Module 9: Routing Events: It focuses on using the Choice router for conditional logic and the Scatter-Gather router to multicast events. This topic also involves validating data by using the Validation module.
• Module 10: Handling Errors: Handling errors includes describing default error handling in Mule applications and defining custom global default error handlers. It involves comparing On Error Continue and On Error Propagate scopes, creating error handlers for a flow, using the Try scope, and mapping errors to custom application errors.
• Module 11: Debugging and Troubleshooting Mule Applications: Using breakpoints to inspect a Mule event during runtime, installing missing Maven dependencies, and reading and deciphering Mule log error messages are sub-topics of this topic.
• Module 12: Deploying and Managing APIs and Integrations: It includes packaging Mule applications for deployment and deploying them to CloudHub. This topic also involves using CloudHub properties, creating and deploying API proxies, connecting an API implementation to API Manager, and applying policies to secure an API.