Proxy

Supported engines

The table below shows supported proxy types for specific engines:

tip

Note that HTTPS requests are currently not supported with the HTTP proxy for the Darwin engine.

Add dependencies

To configure the proxy in the client, you don't need to add a specific dependency. The required dependencies are:

• ktor-client-core;

• an engine dependency.

Configure proxy

To configure proxy settings, call the engine function inside a client configuration block and then use the proxy property. This property accepts the ProxyConfig instance that can be created using the ProxyBuilder factory.

val client = HttpClient() {
    engine {
        proxy = // Create proxy configuration
    }
}

val client = HttpClient() {
    engine {
        proxy = ProxyBuilder.http("http://sample-proxy-server:3128/")
    }
}

val client = HttpClient() {
    engine {
        proxy = Proxy(Proxy.Type.HTTP, InetSocketAddress("sample-proxy-server", 3128))
    }
}

val client = HttpClient() {
    engine {
        proxy = ProxyBuilder.socks(host = "sample-proxy-server", port = 1080)
    }
}

val client = HttpClient() {
    engine {
        proxy = Proxy(Proxy.Type.SOCKS, InetSocketAddress("sample-proxy-server", 1080))
    }
}

Proxy authentication and authorization

Proxy authentication and authorization are engine-specific and should be handled manually. For example, to authenticate a Ktor client to an HTTP proxy server using basic authentication, append the Proxy-Authorization header to each request as follows:

val client = HttpClient() {
    defaultRequest {
        val credentials = Base64.getEncoder().encodeToString("jetbrains:foobar".toByteArray())
        header(HttpHeaders.ProxyAuthorization, "Basic $credentials")
    }
}

To authenticate a Ktor client to a SOCKS proxy on JVM, you can use the java.net.socks.username and java.net.socks.password system properties.