HttpsRedirect

note

This help topic is in development and will be updated in the future.

This feature will make all the affected HTTP calls perform a redirect to its HTTPS counterpart before processing the call.

By default the redirection is a 301 Moved Permanently, but it can be configured to be a 302 Found redirect.

Usage

fun Application.main() {
    install(HttpsRedirect)
    // install(XForwardedHeaderSupport) // Required when behind a reverse-proxy
}

The code above installs the HttpsRedirect feature with the default configuration.

note

When behind a reverse-proxy, you will need to install the ForwardedHeaderSupport or the XForwardedHeaderSupport feature, for the HttpsRedirect feature to properly detect HTTPS requests.

Configuration

fun Application.main() {
    install(HttpsRedirect) {
        // The port to redirect to. By default 443, the default HTTPS port.
        sslPort = 443
        // 301 Moved Permanently, or 302 Found redirect.
        permanentRedirect = true
    }
}

Testing

Applying this feature changes how testing works. After applying this feature, each handleRequest you perform, results in a redirection response. And probably this is not what you want in most cases, since that behaviour is already tested.

XForwardedHeaderSupport trick

As shown in this test , you can install the XForwardedHeaderSupport feature and add a addHeader(HttpHeaders.XForwardedProto, "https") header to the request.

@Test
fun testRedirectHttps() {
    withTestApplication {
        application.install(XForwardedHeaderSupport)
        application.install(HttpsRedirect)
        application.routing {
            get("/") {
                call.respond("ok")
            }
        }
        handleRequest(HttpMethod.Get, "/", {
            addHeader(HttpHeaders.XForwardedProto, "https")
        }).let { call ->
            assertEquals(HttpStatusCode.OK, call.response.status())
        }
    }
}

Do not install the feature when testing or uninstall it

Uninstalling it:

application.uninstall(HttpsRedirect)

Prevent installation in the first place:

// The function referenced in the application.conf
fun Application.mymodule() {
    mymoduleConfigured()
}
// The function referenced in the tests
fun Application.mymoduleForTesting() {
    mymoduleConfigured(installHttpsRedirect = false)
}
fun Application.mymoduleConfigured(installHttpsRedirect: Boolean = true) {
    if (installHttpsRedirect) {
        install(HttpsRedirect)
    }
    // ...
}

In this case, you can also have a separate test that calls mymodule instead of mymoduleForTesting to verify that the HttpsRedirect feature is installed and other things that you are not doing in tests.

I get an infinite redirect when using this feature

Have you installed the XForwardedHeaderSupport or the ForwardedHeaderSupport feature? Check this FAQ entry for more details.