In the five years since I began working on various MuleSoft projects, I’ve seen many bad practices. In this blog, I’ll summarise what I often see and alternatives you can use instead.
1. Overuse of DataWeave
DataWeave is a functional programming language designed for transforming data. Don’t use DataWeave for simpler components like set variables or set payload. Use meaningful variable names and indexes to understand the DataWeave operation. For example, I, j, k, etc., can be hard to understand. So, use meaningful variable names.
2. Monolithic flows
A monolithic architecture is a traditional approach to designing software where an entire application is built as a single, indivisible unit. MuleSoft flows are the backbone of any API and tend to follow this approach. Don’t put everything in one flow. Instead, break down flows and subflows into smaller groups and modules. This will enhance modularity, reusability and better exception handling. In the long run, it will help you write meaningful MUnits.
3. Hardcoding credentials
Storing sensitive information like usernames and passwords directly in your MuleSoft configuration can pose a security risk. Use secure properties, files, externalised configuration, or MuleSoft’s Secure Configuration Properties to store sensitive information. I normally use two properties files for an API: one for storing secure information (like passwords and client IDs) and another for storing externalised parameters in properties files (like response time out).
4. Inefficient logging
Excessive logging can overwhelm your system and hinder performance, while inadequate logging makes it challenging to troubleshoot issues. I suggest implementing a balanced approach to logging. Use an approach like logging incoming and outgoing flows. For example, log incoming and outgoing points in flows/sublows and any decision or logic outcome and req/resp to an external system. Carefully check what is coming in the payload. In some cases, huge payloads are logged. In one instance for an API, someone logged a complete binary payload and it created a performance issue. This can really slow down the system and lead to major issues in production.
5. Tight coupling
Creating integrations with tightly coupled components can limit scalability and maintainability. Use the Publish-Subscribe pattern (such as with MuleSoft’s Anypoint MQ) to decouple components. In some cases, if the use case permits, you can use the Async component, so you don’t have to wait for the synchronous response.
6. Abuse of choice router
People tend to use the choice router everywhere for every situation, which is a problem. Instead, the choice router is meant to be used when you need to use conditional logic that will dictate how your message will be routed through your program. For example, setting a conditional variable can be done with the choice router, but looks bad. Use DataWeave in its place. Use a choice router when you are actually routing something.