v5.1.0

2025-07-07

• New: Response.peekTrailers(). When we changed Response.trailers() to block instead of
  throwing in 5.0.0, we inadvertently removed the ability for callers to peek the trailers
  (by catching the IllegalStateException if they weren't available). This new API restores that
  capability.

• Fix: Don't crash on trailers() if the response doesn't have a body. We broke [Retrofit] users
  who read the trailers on the raw() OkHttp response, after its body was decoded.

v5.0.0

2025-07-02

This is our first stable release of OkHttp since 2023. Here's the highlights if you're upgrading
from OkHttp 4.x:

OkHttp is now packaged as separate JVM and Android artifacts. This allows us to offer
platform-specific features and optimizations. If your build system handles [Gradle module metadata],
this change should be automatic.

MockWebServer has a new coordinate and package name. We didn’t like that our old artifact
depends on JUnit 4 so the new one doesn’t. It also has a better API built on immutable values. (We
intend to continue publishing the old okhttp3.mockwebserver artifact so there’s no urgency to
migrate.)

OkHttp now supports Happy Eyeballs ([RFC 8305][rfc_8305]) for IPv4+IPv6 networks. It attempts
both IPv6 and IPv4 connections concurrently, keeping whichever connects first.

We’ve improved our Kotlin APIs. You can skip the builder:

val request = Request(
  url = "https://cash.app/".toHttpUrl(),
)

OkHttp now supports [GraalVM].

Here’s what has changed since 5.0.0-alpha.17:

• Upgrade: [Okio 3.15.0][okio_3_15_0].
• Upgrade: [Kotlin 2.2.0][kotlin_2_2_0].
• Fix: Don't crash with a NoSuchMethodError when using OkHttp with the Sentry SDK.
• Fix: Retain the query data in the old okhttp3.mockwebserver.RecordedRequest.path property. We
  inadvertently changed this behavior when we introduced the mockwebserver3 API.