devlog-kotlin/dev.hermannm.devlog/LogBuilder

LogBuilder

Class used in the logging methods on Logger, allowing you to add structured key-value data to the log by calling the field and rawJsonField methods.

This class is provided as a receiver for the buildLog lambda parameter on Logger's methods, which lets you call its methods directly in the scope of the lambda. This is a common pattern for creating type-safe builders in Kotlin (see the Kotlin docs for more on this).

Example

private val log = getLogger()

fun example(event: Event) {
  log.info {
    // This lambda gets a LogBuilder receiver, which means that we can call `LogBuilder.field`
    // directly in this scope
    field("event", event)
    "Processing event"
  }
}

Functions

addField

fun addField(field: LogField)

Adds the given log field to the log. This is useful when you have a previously constructed field from the field/rawJsonField top-level functions, that you want to add to a single log.

addFields

fun addFields(fields: Iterable<LogField>)

Adds the given log fields to the log. This is useful when you have a list of previously constructed fields from the field/rawJsonField top-level functions, that you want to add to a single log.

field

inline fun <ValueT> field(key: String, value: ValueT)

fun <ValueT : Any> field(key: String, value: ValueT?, serializer: SerializationStrategy<ValueT>)

Adds a log field (structured key-value data) to the log.

rawJsonField

fun rawJsonField(key: String, json: String, validJson: Boolean = false)

Adds a log field (structured key-value data) to the log, with the given pre-serialized JSON value.