alwaysCache • Akka HTTP (original) (raw)

Signature

def alwaysCache[K](cache: Cache[K, RouteResult], keyer: PartialFunction[RequestContext, K]): Directive0

Description

Like cache but disregards a Cache-Control request header.

Example

Scala

source`` import akka.http.scaladsl.server.directives.CachingDirectives._ import akka.http.scaladsl.server.RequestContext import akka.http.scaladsl.model.Uri import akka.http.scaladsl.model.headers.{ Authorization, Cache-Control } import akka.http.scaladsl.model.headers.CacheDirectives.no-cache

//Example keyer for non-authenticated GET requests val simpleKeyer: PartialFunction[RequestContext, Uri] = { val isGet: RequestContext => Boolean = _.request.method == GET val isAuthorized: RequestContext => Boolean = .request.headers.exists(.is(Authorization.lowercaseName)) val result: PartialFunction[RequestContext, Uri] = { case r: RequestContext if isGet(r) && !isAuthorized(r) => r.request.uri } result }

// Created outside the route to allow using // the same cache across multiple calls val myCache = routeCache[Uri]

var i = 0 val route = path("cached") { alwaysCache(myCache, simpleKeyer) { complete { i += 1 i.toString } } }

Get("/cached") ~> route ~> check { responseAs[String] shouldEqual "1" } // now cached Get("/cached") ~> route ~> check { responseAs[String] shouldEqual "1" } Get("/cached") ~> Cache-Control(no-cache) ~> route ~> check { responseAs[String] shouldEqual "1" } ``

Java

source`final CachingSettings cachingSettings = CachingSettings.create(system()); // Example keyer for non-authenticated GET requests final JavaPartialFunction<RequestContext, Uri> simpleKeyer = new JavaPartialFunction<RequestContext, Uri>() { public Uri apply(RequestContext in, boolean isCheck) { final HttpRequest request = in.getRequest(); final boolean isGet = request.method() == HttpMethods.GET; final boolean isAuthorized = request.getHeader(Authorization.class).isPresent();

if (isGet && !isAuthorized)
  return request.getUri();
else
  throw noMatch();

} };

// Created outside the route to allow using // the same cache across multiple calls final Cache<Uri, RouteResult> myCache = routeCache(cachingSettings);

final AtomicInteger count = new AtomicInteger(0); final Route route = path("cached", () -> alwaysCache(myCache, simpleKeyer, () -> extractUri(uri -> complete(String.format("Request for %s @ count %d", uri, count.incrementAndGet())) ) ) );

// tests: testRoute(route) .run(HttpRequest.GET("/cached")) .assertEntity("Request for http://example.com/cached @ count 1");

// now cached testRoute(route) .run(HttpRequest.GET("/cached")) .assertEntity("Request for http://example.com/cached @ count 1");

final CacheControl noCache = CacheControl.create(CacheDirectives.NO_CACHE); testRoute(route) .run(HttpRequest.GET("/cached").addHeader(noCache)) .assertEntity("Request for http://example.com/cached @ count 1");`

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