Working with custom frontends

Kodein-Log is a facade for multiplatform developers that need an easy way to log without worrying about platform specific implementation. For that we provide [default frontends] that are default output capacities, for each possible target of Kotlin/Multiplatform.

However, we can think of a lot of use cases that might not covered by default frontends, ike saving the logs into a file, sending the logs to an upstream system, etc.

If you want to use a custom implementation to handle your logs, you can create your own by using the interface LogFrontend.

public fun interface LogFrontend {
    public fun getReceiverFor(tag: Logger.Tag): LogReceiver (1)
1 You only have to override getReceiverFor.

The getReceiverFor function will define what we should do of every logged entry. The rest depends on your use case. Here is an example of a frontend that will stack every log into a list:

custom frontend
class MemoryFrontend : LogFrontend { (1)
    val entries: MutableList<Triple<Logger.Tag, Logger.Entry, String?>> = ArrayList() (2)

    override fun getReceiverFor(tag: Logger.Tag): LogReceiver = (3)
        LogReceiver { entry, message -> (4)
            entries += Triple(tag, entry, message) (5)
1 implement LogFrontend
2 create a mutable list that will carry the logs
3 override getReceiveFor
4 create a LogReceiver …​
5 …​ that populate the entries with each log received
We could use this example to periodically send our stack to an upstream server.