How to add delay in Reactor Netty HttpSever response - reactor-netty

Question

I have created a Reactor Netty HTTPSever which works fine, I wanted to add an delay for each response i.e if I send a request I should get the response after say 10 sec, I need this delay to test something. Below is the code used to create the server
DisposableServer server = HttpServer.create().port(port).protocol(HttpProtocol.H2C).metrics(true, s -> s)
.wiretap(false).handle((request, response) -> response.status(httpResponseStatus).send()).bindNow();
server.onDispose().block();

Answer 1

send() method returns Mono, so you can invoke the delay* operators that Mono provides. The example above can be changed like this (this example below delays headers and sends an empty response body):
DisposableServer server =
HttpServer.create()
.port(port)
.protocol(HttpProtocol.H2C)
.metrics(true, s -> s)
.wiretap(false)
.handle((request, response) ->
response.status(httpResponseStatus)
.send()
.delaySubscription(Duration.ofSeconds(10)))
.bindNow();
server.onDispose().block();
Update:
In case the I/O handler needs first to delay and then to send some non empty response, the example can be change to the one below:
DisposableServer server =
HttpServer.create()
.port(port)
.protocol(HttpProtocol.H2C)
.metrics(true, s -> s)
.wiretap(false)
.handle((request, response) ->
Mono.delay(Duration.ofSeconds(10))
.flatMap(l -> {
// Set status code if needed
response.status(httpResponseStatus);
return response.sendString(Mono.just(String.valueOf(responseCode)).then();
}))
.bindNow();
server.onDispose().block();