update: mention the Unix domain socket functionality in making requests

topics/client-default-request.md

@@ -22,7 +22,8 @@ The [DefaultRequest](https://api.ktor.io/ktor-client/ktor-client-core/io.ktor.cl
 
 ## Install DefaultRequest {id="install_plugin"}
 
-To install `DefaultRequest`, pass it to the `install` function inside a [client configuration block](client-create-and-configure.md#configure-client) ...
+To install `DefaultRequest`, pass it to the `install` function inside a [client configuration block](client-create-and-configure.md#configure-client):
+
 ```kotlin
 import io.ktor.client.*
 import io.ktor.client.engine.cio.*
@@ -33,7 +34,7 @@ val client = HttpClient(CIO) {
 }
 ```
 
-... or call the `defaultRequest` function and [configure](#configure) required request parameters:
+Or call the `defaultRequest` function and [configure](#configure) required request parameters:
 
 ```kotlin
 import io.ktor.client.*
@@ -99,6 +100,36 @@ defaultRequest {
 }
 ```
 
+### Unix domain sockets
+
+> Unix domain sockets are supported only in the CIO engine.
+>
+{style="note"}
+
+You can [build individual requests with Unix domain sockets](client-requests.md#specify-a-unix-domain-socket),
+but you can also configure a default request with a socket parameter.
+
+To do that, pass a `unixSocket` call with the path to the socket to the `defaultRequest` function,
+for example:
+
+```kotlin
+val client = HttpClient(CIO)
+
+// Sending a single request to a Unix domain socket
+val response: HttpResponse = client.get("/") {
+    unixSocket("/tmp/test-unix-socket-ktor.sock")
+}
+
+// Setting up the socket for all requests from that client
+val clientDefault = HttpClient(CIO) {
+    defaultRequest {
+        unixSocket("/tmp/test-unix-socket-ktor.sock")
+    }    
+}
+
+val response: HttpResponse = clientDefault.get("/")
+```
+
 ## Example {id="example"}
 
 The example below uses the following `DefaultRequest` configuration:

topics/client-requests.md

@@ -16,6 +16,7 @@ Learn how to make requests and specify various request parameters: a request URL
 After [setting up the client](client-create-and-configure.md), you can make HTTP requests. The main way of making HTTP requests is the [request](https://api.ktor.io/ktor-client/ktor-client-core/io.ktor.client.request/request.html) function that can take a URL as a parameter. Inside this function, you can configure various request parameters: 
 * Specify an HTTP method, such as `GET`, `POST`, `PUT`, `DELETE`, `HEAD`, `OPTIONS`, or `PATCH`.
 * Specify a URL as a string or configure URL components (a domain, a path, query parameters, etc.) separately.
+* Specify a Unix domain socket.
 * Add headers and cookies.
 * Set the body of a request, for example, a plain text, a data object, or form parameters.
 
@@ -119,6 +120,25 @@ You can configure a URL fragment using the `fragment` property.
 Note that `fragment` [encodes][percent_encoding] a URL fragment.
 To disable encoding, use `encodedFragment`.
 
+## Specify a Unix domain socket
+
+> Unix domain sockets are supported only in the CIO engine.
+> To use a Unix socket with a Ktor server, [configure the server](server-configuration-code.topic#cio-code) accordingly.
+> 
+{style="note"}
+
+You can make requests to a server listening to a Unix domain socket by calling the `unixSocket` function
+for a CIO client:
+
+```kotlin
+val client = HttpClient(CIO)
+
+val response: HttpResponse = client.get("/") {
+    unixSocket("/tmp/test-unix-socket-ktor.sock")
+}
+```
+
+You can also set up a Unix domain socket as a part of a [default request](client-default-request.md#unix-domain-sockets). 
 
 ## Set request parameters {id="parameters"}
 In this section, we'll see how to specify various request parameters, including an HTTP method, headers, and cookies. If you need to configure some default parameters for all requests of a specific client, use the [DefaultRequest](client-default-request.md) plugin.
@@ -134,8 +154,7 @@ To add headers to the request, you can use the following ways:
 - The [header](https://api.ktor.io/ktor-client/ktor-client-core/io.ktor.client.request/header.html) function allows you to append a single header.
 - The `basicAuth` and `bearerAuth` functions add the `Authorization` header with a corresponding HTTP scheme.
    > For advanced authentication configuration, refer to [](client-auth.md).
-
-
+
 
 ### Cookies {id="cookies"}
 To send cookies, use the [cookie](https://api.ktor.io/ktor-client/ktor-client-core/io.ktor.client.request/cookie.html) function:
@@ -147,7 +166,6 @@ To send cookies, use the [cookie](https://api.ktor.io/ktor-client/ktor-client-co
 Ktor also provides the [HttpCookies](client-cookies.md) plugin that allows you to keep cookies between calls. If this plugin is installed, cookies added using the `cookie` function are ignored.
 
 
-
 ## Set request body {id="body"}
 To set the body of a request, you need to call the `setBody` function exposed by [HttpRequestBuilder](https://api.ktor.io/ktor-client/ktor-client-core/io.ktor.client.request/-http-request-builder/index.html). This function accepts different types of payloads, including plain text, arbitrary class instances, form data, byte arrays, and so on. Below, we'll take a look at several examples.
 

topics/docker.md

@@ -48,12 +48,11 @@ plugins {
 </tabs>
 
 > The Docker integration is automatically disabled if you apply the Ktor Gradle plugin along with the Kotlin Multiplatform Gradle plugin.
-> To use this feature with KMP, you'll need to move the Ktor plugin to a separate project:
+> To be able to use them together:
 > 1. Create a JVM-only project with the Ktor Gradle plugin applied as shown above.
 > 2. Add the Kotlin Multiplatform project as a dependency to that JVM-only project.
 >
-> If in your case it is necessary to apply both Gradle plugins in the same project,
-> let us know by leaving a comment in [KTOR-8464](https://youtrack.jetbrains.com/issue/KTOR-8464).
+> If this workaround does not solve the problem for you, let us know by leaving a comment in [KTOR-8464](https://youtrack.jetbrains.com/issue/KTOR-8464).
 >
 {style="warning"}
 

topics/server-fatjar.md

@@ -29,12 +29,11 @@ To build a fat JAR, you need to configure the Ktor plugin first:
    {src="snippets/deployment-ktor-plugin/build.gradle.kts" include-lines="28-31,53"}
 
 > The fat JAR creation feature is automatically disabled if you apply the Ktor Gradle plugin along with the Kotlin Multiplatform Gradle plugin.
-> To use this feature with KMP, you'll need to move the Ktor plugin to a separate project:
+> To be able to use them together:
 > 1. Create a JVM-only project with the Ktor Gradle plugin applied as shown above.
 > 2. Add the Kotlin Multiplatform project as a dependency to that JVM-only project.
->
-> If in your case it is necessary to apply both Gradle plugins in the same project,
-> let us know by leaving a comment in [KTOR-8464](https://youtrack.jetbrains.com/issue/KTOR-8464).
+> 
+> If this workaround does not solve the problem for you, let us know by leaving a comment in [KTOR-8464](https://youtrack.jetbrains.com/issue/KTOR-8464).
 >
 {style="warning"}
 

topics/whats-new-320.md

@@ -234,6 +234,37 @@ Ktor’s HTMX support is available across three experimental modules:
 All APIs are marked with `@ExperimentalKtorApi` and require opt-in via `@OptIn(ExperimentalKtorApi::class)`.
 For more information, see [](htmx-integration.md).
 
+## Unix domain sockets
+
+With 3.2.0, you can set up Ktor clients to connect to Unix domain sockets and Ktor servers to listen to such sockets.
+Currently, Unix domain sockets are only supported in the CIO engine.
+
+Example of a server configuration:
+
+```kotlin
+val server = embeddedServer(CIO, configure = {
+    unixConnector("/tmp/test-unix-socket-ktor.sock")
+}) {
+    routing {
+        get("/") {
+            call.respondText("Hello, Unix socket world!")
+        }
+    }
+}
+```
+
+Connecting to that socket using a Ktor client:
+
+```kotlin
+val client = HttpClient(CIO)
+
+val response: HttpResponse = client.get("/") {
+    unixSocket("/tmp/test-unix-socket-ktor.sock")
+}
+```
+
+You can also use a Unix domain socket in a [default request](client-default-request.md#unix-domain-sockets).
+
 ## Infrastructure
 
 ### Published version catalog