Mocked JWT server

JwtServingTest.kt

package ir.amv.enterprise.laas.webapp.common.test.jwt

import com.github.tomakehurst.wiremock.WireMockServer
import com.github.tomakehurst.wiremock.client.WireMock.aResponse
import com.github.tomakehurst.wiremock.client.WireMock.get
import com.github.tomakehurst.wiremock.client.WireMock.urlEqualTo
import com.github.tomakehurst.wiremock.core.WireMockConfiguration
import com.nimbusds.jose.JWSAlgorithm
import com.nimbusds.jose.JWSHeader
import com.nimbusds.jose.crypto.RSASSASigner
import com.nimbusds.jose.jwk.JWKSet
import com.nimbusds.jose.jwk.gen.RSAKeyGenerator
import com.nimbusds.jose.util.JSONObjectUtils
import com.nimbusds.jwt.JWTClaimsSet
import com.nimbusds.jwt.SignedJWT
import org.junit.jupiter.api.AfterAll
import org.springframework.http.HttpHeaders
import org.springframework.http.MediaType
import java.util.Date


open class JwtServingTest {

  private val rsaJWK = RSAKeyGenerator(2048)
      .keyID("123")
      .generate()
  private val wireMockServer: WireMockServer

  val port: Int

  init {
    // assuming we're not even running Spring!
    wireMockServer = WireMockServer(
        WireMockConfiguration()
            .dynamicPort()
    )
    wireMockServer.start()
    port = wireMockServer.port()

    wireMockServer.stubFor(
        get(urlEqualTo("/certs"))
            .willReturn(
                aResponse()
                    .withHeader(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON_VALUE)
                    .withBody(JSONObjectUtils.toJSONString(JWKSet(rsaJWK).toJSONObject()))
            )
    )
  }

  fun generateToken(): String {
    // Create RSA-signer with the private key
    val signer = RSASSASigner(rsaJWK)

    // Prepare JWT with claims set
    val claimsSet = JWTClaimsSet.Builder()
        .subject("alice")
        .issuer("https://c2id.com")
        .expirationTime(Date(Date().time + 60 * 1000))
        .build()

    val signedJWT = SignedJWT(
        JWSHeader.Builder(JWSAlgorithm.RS256).keyID(rsaJWK.getKeyID()).build(),
        claimsSet)

    // Compute the RSA signature
    signedJWT.sign(signer)

    // To serialize to compact form, produces something like
    // eyJhbGciOiJSUzI1NiJ9.SW4gUlNBIHdlIHRydXN0IQ.IRMQENi4nJyp4er2L
    // mZq3ivwoAjqa1uUkSBKFIX7ATndFF5ivnt-m8uApHO4kfIFOrW7w2Ezmlg3Qd
    // maXlS9DhN0nUk_hGI3amEjkKd0BWYCB8vfUbUv0XGjQip78AI4z1PrFRNidm7
    // -jPDm5Iq0SZnjKjCNS5Q15fokXZc8u0A
    return signedJWT.serialize()
  }

  @AfterAll
  fun stopServer() {
    wireMockServer.stop()
  }

}