Swagger timeout on HTTPS listener (and workaround)

[marcus-degruttola]

We changed our site so that Play is listening directly to HTTPS (redirecting HTTP to HTTPS). The call to controllers.ApiHelpController.getResources which worked fine from HTTP was now showing huge latency and timeouts on HTTPS. The swagger validation call in the swagger ui would also timeout and report a red error.

The swagger JSON information would return quickly but play would hold the connection open for long periods of time. The issue (probably not a swagger-play issue) seems to be a bad interaction with the JSON stream parser SSL.

Our workaround was to use this...

class MyApiHelpController @Inject() (components: ControllerComponents, configuration: play.api.Configuration)
extends ApiHelpController(components, configuration) {

def wrappedResources = Action {
request =>
implicit val requestHeader: RequestHeader = request
val host: String = if (configuration.underlying.hasPath("swagger.api.host")) configuration.underlying.getString("swagger.api.host") else requestHeader.host
val resourceListing: io.swagger.models.Swagger = getResourceListing(host)
val response: String = returnXml(request) match {
case true => toXmlString(resourceListing)
case false => toJsonString(resourceListing)
}
myReturnValue(request, response)
}

private def myReturnValue(request: Request[_], obj: Any): Result = {
val response = returnXml(request) match {
case true => XmlResponse(obj)
case false => Ok(obj.toString).as("application/json")
}
response.withHeaders(AccessControlAllowOrigin)
}
}

With this change, the swagger ui and swagger validator call became happy (reported green) and the call to MyApiHelpController.wrappedResources returned quickly. JSON stream parsing becomes JSON blob parsing with this change. Again, the problem only happened on the HTTPS listener.

Versions...
"io.swagger" % "swagger-core" % "1.5.22",
"io.swagger" %% "swagger-play2" % "1.6.1",
"com.typesafe.play" % "sbt-plugin" % "2.6.20"