Hands-On Dependency Injection in Go

Applying config injection to the exchange package

We can apply config injection to the exchange package as we have with the other packages, using the following steps:

1. Define an interface that includes the dependencies and config that we want to inject
2. Define/update the constructor to accept the config interface
3. Save the injected config as a member variable

4. Change the references (for example, to config and logger) to point to the member variable
5. Update the other layer config interfaces to include anything new

After we have applied config injection to the exchange package, an unusual situation emerges. Our dependency graph shows that we have removed the link from the exchange to config packages, as can be seen in the following diagram: ...