kotlinlang #http4k

@arocnies we've been having a nightmare with the tech empower results - we simply cannot reproduce their results locally - and we certainly see much better performance in our prod environments, which run in a completely unoptimized Jetty (apart from choice of GC). For the latest R15 preview 3 (if they ever get around to it!), I've stripped back the implementation to remove the database cases to see if that helps, but I'm not too hopeful TBH. At the very least, there shouldn't be much difference between the Jetty results and our Jetty server backend version - since we're just providing a very thin layer over the top of a servlet. We'll see what happens....

😔 1

dave

11/14/2017, 10:12 AM

cool. thanks @ndchorley - keep plugging away and le tus know where the pain points are (if any!)! 🙂 In terms of a (planned) http4k-session module, I'm intending to provide an a. an interface for session persistence, and b. to use the Lens API to make the session management completely typesafe using SessionKey Lenses. This will make it consistent with the rest of the http4k APIs, so should fit in quite nicely. Now we just need the time (or volunteers) to do the dev work! 🙂

g4sarma

01/15/2018, 4:39 PM

Do you guys have any link or suggestion on some valuable resource for starters ?

dave

01/15/2018, 8:54 PM

@fredrik.nordin looks more like it 🙂 . it's obviously missing the request counter - not sure if you want to put that in as well if you're there? Also, I'm torn as to if to have MetricsFilters object, or to make the Filter creation methods extension methods on ServerFilters and ClientFilters (respectively). Raise the PR and I'll have a mull over that. 🙂

dave

02/23/2018, 3:05 PM

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fun add(value1: Int, value2: Int): HttpHandler = {
        Response(OK).with(
            Body.string(TEXT_PLAIN).toLens() of (value1 + value2).toString()
        )}

    val contract = contract(OpenApi(ApiInfo("my great api", "v1.0"), Argo),
        "/add" / <http://Path.int|Path.int>().of("value1") / Path.fixed("hello") / <http://Path.int|Path.int>().of("value2") meta {
            summary = "add"
            description = "Adds 2 numbers together"
            returning("The result" to OK)
        } bindContract GET
            to { a, _, c -> add(a, c) }
    )

    contract.asServer(Jetty(8000)).start()

dave

02/24/2018, 8:13 AM

@scap one more thing - I've been thinking about is and think we might want to change the security filter order, so it runs the standard filter first, then Security, then an optional post security filter. This would allow things like auditing, monitoring and request context setup to happen first. It would be a breaking change to the API, but I think it's a much better model. Thoughts - or can anyone think of a case where this would be a bad thing?

scap

02/27/2018, 4:46 AM

@elifarley I too have notice this. I have just been living with it but would like to be able to name the object. I haven't found a way.

elifarley

03/02/2018, 1:54 PM

FYI: New PR at https://github.com/http4k/http4k/pull/103 Motivation: JsonIter has a nice API, has lazy evaluation, and is faster than most other JSON libs. (See benchmarks at https://github.com/fabienrenaud/java-json-benchmark) I could simply add JsonIter to my project and use it, but then Http4K lib itself would still use another JSON lib, so I would end up having 2 JSON library dependencies. By having a JsonIter module, I can have only 1 JSON dependency, and as an added bonus, Http4K will use a faster JSON library 😉

elifarley

03/06/2018, 9:46 PM

I have a

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class SimpleObject(val id: String, val attrs: Map<String, Any?>,
                        val created: ZonedDateTime,
                        val updated: ZonedDateTime
)

If I use

with( Header.zonedDateTime().required("last-modified") of obj.created)

, I end up with multiple attributes like

"created":{"dateTime":{"date":{"year":2018,"month":3,...

). I think it should be a single String attribute, based on my understanding of

this.map(ZonedDateTime::parse, DateTimeFormatter.ISO_ZONED_DATE_TIME::format)

in file lensSpec.kt

elifarley

03/07/2018, 6:16 PM

On the generated Swagger API json file, I have a duplicate key in "definitions" :

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"object-1161328054": {
			"type": "object",
			"properties": {}
		},
		"object158819726": {
			"type": "object",
			"properties": {
				"id": {
					"type": "string"
				},
				"attrs": {
					"$ref": "#/definitions/object-1161328054"
				},
				"created": {
					"type": "string"
				},
				"updated": {
					"type": "string"
				}
			}
		},
		"object-1161328054": {
			"type": "object",
			"properties": {}
		},

dave

03/09/2018, 6:51 AM

Normally we bind inside a with method call. Try calling it with the parens instead of infixed?

elifarley

03/09/2018, 10:37 AM

I have an HttpHandler that is returning

HTTP/1.1 400 body 'body' must be object

This message is hiding an exception. How can I get hold of it? I have these filters:

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routes(
"/sgzr/api/v1" bind Api.router(productService, orderService)
).let {
DebuggingFilters.PrintRequestAndResponse()
                .then(ServerFilters.Cors(CorsPolicy.UnsafeGlobalPermissive))
                .then(ServerFilters.CatchAll())
                .then(ServerFilters.CatchLensFailure)
                .then(it)
}

dave

03/20/2018, 9:58 PM

@scap not in the spec. Or in the next version... https://stackoverflow.com/questions/42335178/swagger-wildcard-path-parameters

dave

03/28/2018, 4:35 PM

After a bit of a struggle with maven central, we've released v3.22.2 of http4k. New in this release: - A new OAuth module http4k-security-oauth, allowing for super simple integration with OAuth providers. Including pre configured instances for popular services like Google, Dropbox and Auth0 - Rewrite of static resource loaders to remove dependencies on javax.activation - previously this broke when upgrading to java 9 and above - Squashed a weird header bug with the Apache client which broke f5 load balancers.

👏 1

dave

04/06/2018, 7:30 PM

@elifarley Thanks for the PR - I've managed to fix it in a more generic way - you can now optionally provide a function when creating the

CatchLensFailure

to create a custom response. New method looks like this:

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ServerFilters.CatchLensFailure { lensFailure -> Response(OK).body(lensFailure.localizedMessage) }

. Releasing in 3.23.0

joscha.alisch

04/10/2018, 5:50 PM

Thanks @dave! It’s as simple as this:

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import org.http4k.contract.*
import org.http4k.core.*
import org.http4k.format.Jackson
import org.http4k.format.Jackson.auto
import org.http4k.routing.bind
import org.http4k.routing.routes
import org.http4k.server.Jetty
import org.http4k.server.asServer

data class MyDataClass(val something: String)
val requestBody = Body.auto<MyDataClass>().toLens()

fun main(args: Array<String>) {
    routes(
        "/api" bind contract(OpenApi(ApiInfo("My great API", "v1.0"), Jackson),"/route" meta {
            body = requestBody
        } bindContract Method.GET to ::handler)
    ).asServer(Jetty(5000)).start()
}

fun handler(request: Request): Response {
    return Response(Status.OK)
}

gives me

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{
  “swagger” : “2.0",
  “info” : {
    “title” : “My great API”,
    “version” : “v1.0”,
    “description” : “”
  },
  “basePath” : “/”,
  “tags” : [ ],
  “paths” : {
    “/api/route” : {
      “get” : {
        “tags” : [ “/api” ],
        “summary” : “<unknown>“,
        “description” : null,
        “produces” : [ ],
        “consumes” : [ “application/json” ],
        “parameters” : [ {
          “in” : “body”,
          “name” : “body”,
          “description” : null,
          “required” : true,
          “type” : “object”
        } ],
        “responses” : { },
        “supportedContentTypes” : [ ],
        “security” : [ ]
      }
    }
  },
  “securityDefinitions” : { },
  “definitions” : { }
}

RichyHBM

04/25/2018, 6:28 PM

Also, anyone recommend an form library that plays well with http4k?

dave

04/25/2018, 7:46 PM

@RichyHBM I generally default to handlebars, but would be interested to hear other opinions, or for libs that we could integrate with.

dave

06/15/2018, 7:53 AM

@maybetrinity The same goes for the regexes - we'll see what we can do to add some simpled Kotlin wrappers to make this easy. The only thing about regexes are that they are inherently one way. If might make more sense to wrap the strings in a microtype (ie a data class with one field) and handle the (de)marshalling inside the construction of that type.

👍 1

dave

06/20/2018, 9:16 AM

We'd love to see if you manage to get it running - although beware that the netty implementation is the least mature of all the server backends. I've not used it in a prod environment myself - I generally default to Undertow,

andyD

06/20/2018, 9:55 PM

Hey, I think the docs here https://www.http4k.org/guide/modules/message_formats/ are incorrect as the latest version for Jackson is 3.28.0 according to https://search.maven.org/#search%7Cga%7C1%7Ca%3A%22http4k-format-jackson%22

RichyHBM

06/21/2018, 7:58 PM

I can do, for now it's here https://www.richyhbm.co.uk/posts/compiling-kotlin-netty-webapp-with-graalvm/

👍 2

s4nchez

06/25/2018, 8:47 AM

@zero.meta Actually, @dave reminded me that the correct format for the above example is

/foo/{bar:.*}

(the

is important ;))

dave

07/11/2018, 10:35 AM

@pabl0rg just an update on the tech empower benchmarks... Your suggestion of swapping out handlebars for pebble has had a significant uptick in the performance of the fortunes test. Comparative results for JVM frameworks based on the latest run: Handlebars - 11th position - 167k requests served - 48% compared to top performer Pebble - 6th position - 225k requests served - 67% compared to top performer See the full set here: https://www.techempower.com/benchmarks/#section=test&runid=898a9857-e2a6-472c-ac4e-f0d0c851af30&hw=ph&test=fortune&l=xan3i3-1

💪 8

napperley

07/23/2018, 11:07 PM

Would it be possible to use HTTP4K in a OpenFaaS (https://www.openfaas.com) template? I have a Kotlin JVM OpenFaaS template (https://github.com/napperley/openfaas-kotlin-templates/tree/kotlin-jvm/template/kotlin-jvm) that needs to be refactored to use a HTTP/S server to handle input/output. This template is partially based on the official OpenFaaS Java 8 template (https://github.com/openfaas/templates/tree/master/template/java8).

dave

08/15/2018, 9:09 PM

@elifarley thanks for the PR - we'll look at getting it in soon - we just want to be extra careful as we've had the opposite experience - servers rejecting host headers when there is a port set. Out of interest, what is the server that rejects it without the port?

dave

08/21/2018, 1:12 PM

@Xavier Hanin sure. http4k was developed as a personal side project (and then subsequently used on) the redevelopment of www.nature.com (a major scientific publisher- where it makes up the vast bulk of the micro-service backend infra, serving 10s of millions of hits per day from a cloud-based backend. The number of nodes of each service probably averages at 6 . You can see the alexa.com stats here (it's 810 in the Global ranking, 395 in China): https://www.alexa.com/siteinfo/nature.com I can't disclose the names of the banks unfortunately. Performance-wise, you can take a look at the latest tech-empower rankings to see how it compares (I've filtered here for JVM only): https://www.techempower.com/benchmarks/#section=test&runid=06753cdf-6519-4569-b9ea-c3ca36c9b07d&hw=ph&test=fortune&l=xan3i3-3

👍 1

Albert

09/10/2018, 6:01 PM

Just opened PR for http4k https://github.com/adhesivee/kotlin-oauth2-server/pull/20 (still need to update docs)

David Hamilton

09/11/2018, 10:33 AM

💡 Thanks!

dave

10/03/2018, 6:10 PM

@… that sounds wrong. We'll look at fixing it up if it doesn't make sense- thanks for pointing it out. I'll also look at how we can answer your query re: the response schema