Add docs, silent mima

README.md

@@ -78,6 +78,11 @@ val records: IO[ConsumerRecords[String, String]] = consumer.use { consumer =>
 ## Java client metrics example
 
 The example below demonstrates creation of `Consumer`, but same can be done for `Producer` as well.
+
+> :warning: Creating consumer/producer will register new set of metrics in Prometheus registry
+> thus metric names must not clash. For that you have to provide function of type `ClientId => String`,
+> that takes client ID and returns metric prefix. The prefix expected to be unique!
+
 ```scala
 import ConsumerMetricsOf.*
 

build.sbt

@@ -39,7 +39,9 @@ lazy val commonSettings = Seq(
     ProblemFilters.exclude[ReversedMissingMethodProblem]("com.evolutiongaming.skafka.consumer.Consumer.subscribe"),
     ProblemFilters.exclude[DirectMissingMethodProblem](
       "com.evolutiongaming.skafka.Converters#MapJOps.asScalaMap$extension"
-    )
+    ),
+    ProblemFilters.exclude[DirectMissingMethodProblem]("com.evolutiongaming.skafka.consumer.ConsumerMetrics#ConsumerMetricsOps.mapK$extension"),
+    ProblemFilters.exclude[DirectMissingMethodProblem]("com.evolutiongaming.skafka.producer.ProducerMetrics#ProducerMetricsOps.mapK$extension"),
   )
 )
 

modules/metrics/src/main/scala/com/evolutiongaming/skafka/consumer/ConsumerMetricsOf.scala

@@ -10,6 +10,14 @@ import scala.concurrent.duration.FiniteDuration
 
 object ConsumerMetricsOf {
 
+  /**
+    * Construct [[ConsumerMetrics]] that will expose Java Kafka client metrics.
+    *
+    * @param source original [[ConsumerMetrics]]
+    * @param prefix function that provides _unique_ prefix for each client
+    * @param prometheus instance of Prometheus registry
+    * @return [[ConsumerMetrics]] that exposes Java Kafka client metrics
+    */
   def withJavaClientMetrics[F[_]: Sync: ToTry](
     source: ConsumerMetrics[F],
     prefix: ClientId => String,
@@ -47,6 +55,13 @@ object ConsumerMetricsOf {
 
   implicit final class Syntax[F[_]](val source: ConsumerMetrics[F]) extends AnyVal {
 
+    /**
+      * Construct [[ConsumerMetrics]] that will expose Java Kafka client metrics.
+      *
+      * @param prefix function that provides _unique_ prefix for each client
+      * @param prometheus instance of Prometheus registry
+      * @return [[ConsumerMetrics]] that exposes Java Kafka client metrics
+      */
     def exposeJavaClientMetrics(
       prefix: ClientId => String,
       prometheus: CollectorRegistry

modules/metrics/src/main/scala/com/evolutiongaming/skafka/producer/ProducerMetricsOf.scala

@@ -10,6 +10,14 @@ import scala.concurrent.duration.FiniteDuration
 
 object ProducerMetricsOf {
 
+  /**
+    * Construct [[ProducerMetrics]] that will expose Java Kafka client metrics.
+    *
+    * @param source original [[ProducerMetrics]]
+    * @param prefix function that provides _unique_ prefix for each client
+    * @param prometheus instance of Prometheus registry
+    * @return [[ProducerMetrics]] that exposes Java Kafka client metrics
+    */
   def withJavaClientMetrics[F[_]: Sync: ToTry](
     source: ProducerMetrics[F],
     prefix: ClientId => String,
@@ -49,6 +57,13 @@ object ProducerMetricsOf {
 
   implicit final class Syntax[F[_]](val source: ProducerMetrics[F]) extends AnyVal {
 
+    /**
+      * Construct [[ProducerMetrics]] that will expose Java Kafka client metrics.
+      *
+      * @param prefix function that provides _unique_ prefix for each client
+      * @param prometheus instance of Prometheus registry
+      * @return [[ProducerMetrics]] that exposes Java Kafka client metrics
+      */
     def exposeJavaClientMetrics(
       prefix: ClientId => String,
       prometheus: CollectorRegistry