Node.js Design Patterns: Master a series of patterns and techniques to create modular, scalable, and efficient applications

by Mario Casciaro

Also, like dependency injection, using a service locator makes it harder to identify the relationship between the components, as they are resolved at runtime. But in addition it also makes it more difficult to know exactly what dependency a particular component is going to require. With dependency injection this is expressed in a much clearer way, by declaring the dependencies in the factory or constructor arguments. With a service locator, this is much less clear and would require a code inspection or an explicit statement in the documentation explaining what dependencies a particular component will try to load.