Release 4.0.0-M20

README.md

@@ -48,15 +48,15 @@ sttp (v2) documentation is available at [sttp.softwaremill.com/en/v2](https://st
 
 sttp (v1) documentation is available at [sttp.softwaremill.com/en/v1](https://sttp.softwaremill.com/en/v1).
 
-scaladoc is available at [https://www.javadoc.io](https://www.javadoc.io/doc/com.softwaremill.sttp.client4/core_2.12/4.0.0-M19)
+scaladoc is available at [https://www.javadoc.io](https://www.javadoc.io/doc/com.softwaremill.sttp.client4/core_2.12/4.0.0-M20)
 
 ## Quickstart with scala-cli
 
 Add the following directive to the top of your scala file to add the core sttp dependency:
 If you are using [scala-cli](https://scala-cli.virtuslab.org), you can quickly start experimenting with sttp by copy-pasting the following:
 
 ```
-//> using dep "com.softwaremill.sttp.client4::core:4.0.0-M19"
+//> using dep "com.softwaremill.sttp.client4::core:4.0.0-M20"
 import sttp.client4.quick._
 quickRequest.get(uri"http://httpbin.org/ip").send()
 ```
@@ -68,7 +68,7 @@ The `quick` package import brings in the sttp API and a pre-configured, global s
 Similarly, using [Ammonite](http://ammonite.io):
 
 ```scala
-import $ivy.`com.softwaremill.sttp.client4::core:4.0.0-M19`
+import $ivy.`com.softwaremill.sttp.client4::core:4.0.0-M20`
 import sttp.client4.quick._
 quickRequest.get(uri"http://httpbin.org/ip").send()
 ```
@@ -78,7 +78,7 @@ quickRequest.get(uri"http://httpbin.org/ip").send()
 Add the following dependency:
 
 ```scala
-"com.softwaremill.sttp.client4" %% "core" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "core" % "4.0.0-M20"
 ```
 
 Then, import:
@@ -135,7 +135,7 @@ The documentation is typechecked using [mdoc](https://scalameta.org/mdoc/). The
 
 When generating documentation, it's best to set the version to the current one, so that the generated doc files don't include modifications with the current snapshot version. 
 
-That is, in sbt run: `set version := "4.0.0-M19"`, before running `mdoc` in `docs`.
+That is, in sbt run: `set version := "4.0.0-M20"`, before running `mdoc` in `docs`.
 
 ### Testing the Scala.JS backend
 

generated-docs/out/backends/akka.md

@@ -3,7 +3,7 @@
 This backend is based on [akka-http](http://doc.akka.io/docs/akka-http/current/scala/http/). To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %% "akka-http-backend" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "akka-http-backend" % "4.0.0-M20"
 ```
 
 A fully **asynchronous** backend. Uses the `Future` effect to return responses. There are also [other `Future`-based backends](future.md), which don't depend on Akka. 

generated-docs/out/backends/catseffect.md

@@ -14,7 +14,7 @@ Also note that the [http4s](http4s.md) backend can also be created for a type im
 Firstly, add the following dependency to your project:
 
 ```scala
-"com.softwaremill.sttp.client4" %% "cats" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "cats" % "4.0.0-M20"
 ```
 
 Obtain a cats-effect `Resource` which creates the backend, and closes the thread pool after the resource is no longer used:
@@ -82,9 +82,9 @@ Creation of the backend can be done in two basic ways:
 Firstly, add the following dependency to your project:
 
 ```scala
-"com.softwaremill.sttp.client4" %% "armeria-backend-cats" % "4.0.0-M19" // for cats-effect 3.x
+"com.softwaremill.sttp.client4" %% "armeria-backend-cats" % "4.0.0-M20" // for cats-effect 3.x
 // or
-"com.softwaremill.sttp.client4" %% "armeria-backend-cats-ce2" % "4.0.0-M19" // for cats-effect 2.x
+"com.softwaremill.sttp.client4" %% "armeria-backend-cats-ce2" % "4.0.0-M20" // for cats-effect 2.x
 ```
 
 create client:

generated-docs/out/backends/finagle.md

@@ -3,7 +3,7 @@
 To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %% "finagle-backend" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "finagle-backend" % "4.0.0-M20"
 ```
 
 Next you'll need to add an implicit value:

generated-docs/out/backends/fs2.md

@@ -12,9 +12,9 @@ Creation of the backend can be done in two basic ways:
 Firstly, add the following dependency to your project:
 
 ```scala
-"com.softwaremill.sttp.client4" %% "fs2" % "4.0.0-M19" // for cats-effect 3.x & fs2 3.x
+"com.softwaremill.sttp.client4" %% "fs2" % "4.0.0-M20" // for cats-effect 3.x & fs2 3.x
 // or 
-"com.softwaremill.sttp.client4" %% "fs2ce2" % "4.0.0-M19" // for cats-effect 2.x & fs2 2.x
+"com.softwaremill.sttp.client4" %% "fs2ce2" % "4.0.0-M20" // for cats-effect 2.x & fs2 2.x
 ```
 
 Obtain a cats-effect `Resource` which creates the backend, and closes the thread pool after the resource is no longer used:
@@ -78,9 +78,9 @@ Host header override is supported in environments running Java 12 onwards, but i
 To use, add the following dependency to your project:
 
 ```scala
-"com.softwaremill.sttp.client4" %% "armeria-backend-fs2" % "4.0.0-M19" // for cats-effect 3.x & fs2 3.x
+"com.softwaremill.sttp.client4" %% "armeria-backend-fs2" % "4.0.0-M20" // for cats-effect 3.x & fs2 3.x
 // or
-"com.softwaremill.sttp.client4" %% "armeria-backend-fs2" % "4.0.0-M19" // for cats-effect 2.x & fs2 2.x
+"com.softwaremill.sttp.client4" %% "armeria-backend-fs2" % "4.0.0-M20" // for cats-effect 2.x & fs2 2.x
 ```
 
 create client:

generated-docs/out/backends/future.md

@@ -20,7 +20,7 @@ Class                                 Supported stream type
 To use, you don't need any extra dependencies, `core` is enough:
 
 ```
-"com.softwaremill.sttp.client4" %% "core" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "core" % "4.0.0-M20"
 ```
 
 You'll need the following imports:
@@ -59,7 +59,7 @@ Host header override is supported in environments running Java 12 onwards, but i
 To use, add the following dependency to your project:
 
 ```scala
-"com.softwaremill.sttp.client4" %% "okhttp-backend" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "okhttp-backend" % "4.0.0-M20"
 ```
 
 and some imports:
@@ -91,7 +91,7 @@ This backend depends on [OkHttp](http://square.github.io/okhttp/) and fully supp
 To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %% "armeria-backend" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "armeria-backend" % "4.0.0-M20"
 ```
 
 add imports:

generated-docs/out/backends/http4s.md

@@ -3,9 +3,9 @@
 This backend is based on [http4s](https://http4s.org) (client) and is **asynchronous**. To use, add the following dependency to your project:
 
 ```scala
-"com.softwaremill.sttp.client4" %% "http4s-backend" % "4.0.0-M19" // for cats-effect 3.x & http4s 1.0.0-Mx
+"com.softwaremill.sttp.client4" %% "http4s-backend" % "4.0.0-M20" // for cats-effect 3.x & http4s 1.0.0-Mx
 // or
-"com.softwaremill.sttp.client4" %% "http4s-ce2-backend" % "4.0.0-M19" // for cats-effect 2.x & http4s 0.21.x
+"com.softwaremill.sttp.client4" %% "http4s-ce2-backend" % "4.0.0-M20" // for cats-effect 2.x & http4s 0.21.x
 ```
 
 The backend can be created in a couple of ways, e.g.:

generated-docs/out/backends/javascript/fetch.md

@@ -7,7 +7,7 @@ A JavaScript backend with web socket support. Implemented using the [Fetch API](
 This is the default backend, available in the main jar for JS. To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %%% "core" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %%% "core" % "4.0.0-M20"
 ```
 
 And create the backend instance:
@@ -26,7 +26,7 @@ Note that `Fetch` does not pass cookies by default. If your request needs cookie
 To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %%% "monix" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %%% "monix" % "4.0.0-M20"
 ```
 
 And create the backend instance:
@@ -40,7 +40,7 @@ val backend = FetchMonixBackend()
 To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %%% "zio" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %%% "zio" % "4.0.0-M20"
 ```
 
 And create the backend instance:
@@ -55,13 +55,13 @@ Any effect implementing the cats-effect `Concurrent` typeclass can be used. To u
 your project:
 
 ```
-"com.softwaremill.sttp.client4" %%% "cats" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %%% "cats" % "4.0.0-M20"
 ```
 
 If you are on Cats Effect 2 (CE2) you will need to add the CE2 specific dependency instead:
 
 ```
-"com.softwaremill.sttp.client4" %%% "catsce2 % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %%% "catsce2 % "4.0.0-M20"
 ```
 
 And create the backend instance:
@@ -129,7 +129,7 @@ Streaming support is provided via `FetchMonixBackend`. Note that streaming suppo
 To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %%% "monix" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %%% "monix" % "4.0.0-M20"
 ```
 
 An example of streaming a response:

generated-docs/out/backends/monix.md

@@ -12,7 +12,7 @@ Creation of the backend can be done in two basic ways:
 Firstly, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %% "monix" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "monix" % "4.0.0-M20"
 ```
 
 and create the backend using:
@@ -50,7 +50,7 @@ Host header override is supported in environments running Java 12 onwards, but i
 To use, add the following dependency to your project:
 
 ```scala
-"com.softwaremill.sttp.client4" %% "okhttp-backend-monix" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "okhttp-backend-monix" % "4.0.0-M20"
 ```
 
 Create the backend using:
@@ -76,7 +76,7 @@ This backend depends on [OkHttp](http://square.github.io/okhttp/) and fully supp
 To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %% "armeria-backend-monix" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "armeria-backend-monix" % "4.0.0-M20"
 ```
 
 add imports:

generated-docs/out/backends/native/curl.md

@@ -5,7 +5,7 @@ A Scala Native backend implemented using [Curl](https://github.com/curl/curl/blo
 To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %%% "core" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %%% "core" % "4.0.0-M20"
 ```
 
 and initialize one of the backends:

generated-docs/out/backends/pekko.md

@@ -3,7 +3,7 @@
 This backend is based on [pekko-http](https://pekko.apache.org/docs/pekko-http/current/). To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %% "pekko-http-backend" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "pekko-http-backend" % "4.0.0-M20"
 ```
 
 A fully **asynchronous** backend. Uses the `Future` effect to return responses. There are also [other `Future`-based backends](future.md), which don't depend on Pekko. 

generated-docs/out/backends/scalaz.md

@@ -8,7 +8,7 @@ The [Scalaz](https://github.com/scalaz/scalaz) backend is **asynchronous**. Send
 To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %% "armeria-backend-scalaz" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "armeria-backend-scalaz" % "4.0.0-M20"
 ```
 
 add imports:

generated-docs/out/backends/synchronous.md

@@ -7,7 +7,7 @@ There are several synchronous backend implementations. Sending a request using t
 The default **synchronous** backend. To use, you don't need any extra dependencies, `core` is enough:
 
 ```
-"com.softwaremill.sttp.client4" %% "core" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "core" % "4.0.0-M20"
 ```
 
 Create the backend using:
@@ -40,7 +40,7 @@ Host header override is supported in environments running Java 12 onwards, but i
 To use, you don't need any extra dependencies, `core` is enough: 
 
 ```
-"com.softwaremill.sttp.client4" %% "core" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "core" % "4.0.0-M20"
 ```
 
 Create the backend using:
@@ -62,7 +62,7 @@ This backend supports host header override, but it has to be enabled by system p
 To use, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %% "okhttp-backend" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "okhttp-backend" % "4.0.0-M20"
 ```
 
 Create the backend using:
@@ -99,7 +99,7 @@ Both HttpClient and OkHttp backends support regular [websockets](../websockets.m
 
 ```
 // sbt dependency
-"com.softwaremill.sttp.client4" %% "ox" % "4.0.0-M19",
+"com.softwaremill.sttp.client4" %% "ox" % "4.0.0-M20",
 ```
 
 ```scala 

generated-docs/out/backends/wrappers/custom.md

@@ -10,13 +10,13 @@ Possible use-cases for wrapper-backend include:
 
 See also the section on [resilience](../../resilience.md) which covers topics such as retries, circuit breaking and rate limiting.
 
-## Request tagging
+## Request attributes
 
-Each request contains a `tags: Map[String, Any]` map. This map can be used to tag the request with any backend-specific information, and isn't used in any way by sttp itself.
+Each request contains a `attributes: AttributeMap` type-safe map. This map can be used to tag the request with any backend-specific information, and isn't used in any way by sttp itself.
 
-Tags can be added to a request using the `def tag(k: String, v: Any)` method, and read using the `def tag(k: String): Option[Any]` method.
+Attributes can be added to a request using the `def attribute[T](k: AttributeKey[T], v: T)` method, and read using the `def attribute[T](k: Attribute[T]): Option[T]` method.
 
-Backends, or backend wrappers can use tags e.g. for logging, passing a metric name, using different connection pools, or even different delegate backends.
+Backends, or backend wrappers can use attributes e.g. for logging, passing a metric name, using different connection pools, or even different delegate backends.
 
 ## Listener backend
 
@@ -42,13 +42,15 @@ Below is an example on how to implement a backend wrapper, which sends
 metrics for completed requests and wraps any `Future`-based backend:
 
 ```scala
+import sttp.attributes.AttributeKey
 import sttp.capabilities.Effect
 import sttp.client4._
 import sttp.client4.akkahttp._
 import sttp.client4.wrappers.DelegateBackend
 import scala.concurrent.Future
 import scala.concurrent.ExecutionContext.Implicits.global
 import scala.util._
+
 // the metrics infrastructure
 trait MetricsServer {
   def reportDuration(name: String, duration: Long): Unit
@@ -58,6 +60,9 @@ class CloudMetricsServer extends MetricsServer {
   override def reportDuration(name: String, duration: Long): Unit = ???
 }
 
+case class MetricPrefix(prefix: String)
+val MetricPrefixAttributeKey = AttributeKey[MetricPrefix]
+
 // the backend wrapper
 abstract class MetricWrapper[P](delegate: GenericBackend[Future, P],
                        metrics: MetricsServer)
@@ -67,7 +72,7 @@ abstract class MetricWrapper[P](delegate: GenericBackend[Future, P],
     val start = System.currentTimeMillis()
 
     def report(metricSuffix: String): Unit = {
-      val metricPrefix = request.tag("metric").getOrElse("?")
+      val metricPrefix = request.attribute(MetricPrefixAttributeKey).getOrElse(MetricPrefix("?"))
       val end = System.currentTimeMillis()
       metrics.reportDuration(metricPrefix + "-" + metricSuffix, end - start)
     }
@@ -93,7 +98,7 @@ val backend = MetricWrapper(AkkaHttpBackend(), new CloudMetricsServer())
 
 basicRequest
   .get(uri"http://company.com/api/service1")
-  .tag("metric", "service1")
+  .attribute(MetricPrefixAttributeKey, MetricPrefix("service1"))
   .send(backend)
 ```
 
@@ -260,7 +265,7 @@ object RateLimitingSttpBackend {
 Implementing a new backend is made easy as the tests are published in the `core` jar file under the `tests` classifier. Simply add the follow dependencies to your `build.sbt`:
 
 ```
-"com.softwaremill.sttp.client4" %% "core" % "4.0.0-M19" % Test classifier "tests"
+"com.softwaremill.sttp.client4" %% "core" % "4.0.0-M20" % Test classifier "tests"
 ```
 
 Implement your backend and extend the `HttpTest` class:
@@ -288,9 +293,9 @@ import sttp.client4.impl.cats.implicits._
 from the cats integration module. The module should be available on the classpath after adding following dependency:
 
 ```scala
-"com.softwaremill.sttp.client4" %% "cats" % "4.0.0-M19" // for cats-effect 3.x
+"com.softwaremill.sttp.client4" %% "cats" % "4.0.0-M20" // for cats-effect 3.x
 // or
-"com.softwaremill.sttp.client4" %% "catsce2" % "4.0.0-M19" // for cats-effect 2.x
+"com.softwaremill.sttp.client4" %% "catsce2" % "4.0.0-M20" // for cats-effect 2.x
 ```
 
 The object contains implicits to convert a cats `MonadError` into the sttp `MonadError`, 

generated-docs/out/backends/wrappers/logging.md

@@ -28,7 +28,7 @@ Log levels can be configured when creating the `LoggingBackend`, or specified in
 To use the [slf4j](http://www.slf4j.org) logging backend wrapper, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %% "slf4j-backend" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "slf4j-backend" % "4.0.0-M20"
 ``` 
 
 There are three backend wrappers available, which log request & response information using a slf4j `Logger`. To see the logs, you'll need to use an slf4j-compatible logger implementation, e.g.  [logback](http://logback.qos.ch), or use a binding, e.g. [log4j-slf4j](https://logging.apache.org/log4j/2.x/log4j-slf4j-impl.html).
@@ -53,5 +53,5 @@ To create a customised logging backend, see the section on [custom backends](cus
 To use the [scribe](https://github.com/outr/scribe) logging backend wrapper, add the following dependency to your project:
 
 ```
-"com.softwaremill.sttp.client4" %% "scribe-backend" % "4.0.0-M19"
+"com.softwaremill.sttp.client4" %% "scribe-backend" % "4.0.0-M20"
 ```