Cors issue with allowedOrigins in play framework 2.8.15 using hocon variables

Question

There is a java application, which use java, scala, playframework and maven.

jdk 11.0.14
play2 version 2.8.15
scala.version 2.12.15
play2.plugin.version 1.0.0-rc6-SNAPSHOT
sbt-compiler.plugin.version   1.0.0

application.conf

play.application.loader = "loader.BasicApplicationLoader"

play.modules.disabled += "play.core.ObjectMapperModule"
play.modules.enabled += "modules.WebObjectMapperModule"

play.modules.enabled += "modules.StartUpModule"
play.modules.enabled += "modules.ClusterMonitoringModule"
play.modules.enabled += "com.kenshoo.play.metrics.PlayModule"

play.filters.enabled = [
    "play.filters.gzip.GzipFilter",
    "com.kenshoo.play.metrics.MetricsFilter",
    "http.filters.ClusterStatusFilter",
    "play.filters.cors.CORSFilter"
]

play.http.actionCreator = "http.BasicActionCreator"
play.http.requestHandler = "http.WebHttpRequestHandler"
play.http.errorHandler = "http.BasicErrorHandler"

server1.host="http://localhost:9000/"
server2.host="http://localhost:2000/"
server3.host="http://localhost:11000/"

play.filters.cors {
     pathPrefixes = ["/"]
     allowedOrigins = [${?server1.host}, ${?server2.host}, ${?server3.host}]
     allowedHttpMethods = ["GET", "POST", "PUT", "DELETE", "OPTIONS"]
     allowedHttpHeaders = ["Accept", "Origin", "Content-Type"]
     exposedHeaders = ["X-TOTAL-PAGE-COUNT", "X-TOTAL-ELEMENT-COUNT"]
     preflightMaxAge = 1 hour
}

response.delay.milliseconds=500

According to the Play documentation this should work, but it does not, i get the cors error:

Access to XMLHttpRequest at 'https://localhost:8080' from origin 'https://localhost:9000' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

What I have tried so far?

I have checked on the server, where I have deployed if the variables used are correctly interpreted, and yes, they are. I need to use variables like this, because the values of this urls are overriden on the server at deploy time according to the environment needed.

Tried to add in the exposedHeader the Access-Control-Allow-Origin, tried to add it in the allowedHttpHeaders and no luck..

Answer 1

So, after posting this questions I have figured out the question.

The issue were those server values:

server1.host="http://localhost:9000/"
server2.host="http://localhost:2000/"
server3.host="http://localhost:11000/" especially the slash (/) at the end.

For the browser was origin "http://localhost:9000" without slash and that is why the difference.