diff --git a/src/test/kotlin/com/vonage/client/kt/AbstractTest.kt b/src/test/kotlin/com/vonage/client/kt/AbstractTest.kt
index 746cae3..3f95231 100644
--- a/src/test/kotlin/com/vonage/client/kt/AbstractTest.kt
+++ b/src/test/kotlin/com/vonage/client/kt/AbstractTest.kt
@@ -1,21 +1,28 @@
 package com.vonage.client.kt
 
+import com.fasterxml.jackson.databind.ObjectMapper
 import com.github.tomakehurst.wiremock.WireMockServer
+import com.github.tomakehurst.wiremock.client.WireMock
 import com.github.tomakehurst.wiremock.common.ConsoleNotifier
 import com.github.tomakehurst.wiremock.core.WireMockConfiguration.options
+import com.marcinziolo.kotlin.wiremock.*
+import com.vonage.client.common.HttpMethod
 import org.junit.jupiter.api.AfterEach
 import org.junit.jupiter.api.BeforeEach
 
 abstract class AbstractTest {
+    val apiKey = "a1b2c3d4"
+    val applicationId = "00000000-0000-4000-8000-000000000000"
+    private val apiSecret = "1234567890abcdef"
+    private val apiKeySecretEncoded = "YTFiMmMzZDQ6MTIzNDU2Nzg5MGFiY2RlZg=="
+
     val port = 8081
     val wiremock: WireMockServer = WireMockServer(
         options().port(port).notifier(ConsoleNotifier(false))
     )
 
     val vonageClient = Vonage {
-        apiKey("a1b2c3d4")
-        apiSecret("1234567890abcdef")
-        applicationId("00000000-0000-4000-8000-000000000000")
+        apiKey(apiKey); apiSecret(apiSecret); applicationId(applicationId)
         privateKeyPath("src/test/resources/com/vonage/client/kt/application_key")
         httpConfig {
             baseUri("http://localhost:$port")
@@ -32,4 +39,52 @@ abstract class AbstractTest {
         wiremock.resetAll()
         wiremock.stop()
     }
+
+    protected enum class ContentType(val mime: String) {
+        APPLICATION_JSON("application/json"),
+        FORM_URLENCODED("application/x-www-form-urlencoded");
+
+        @Override
+        override fun toString(): String {
+            return mime
+        }
+    }
+
+    protected enum class AuthType {
+        JWT, API_KEY_SECRET
+    }
+
+    protected fun baseMockRequest(
+        httpMethod: HttpMethod,
+        expectedUrl: String,
+        contentType: ContentType?,
+        accept: ContentType?,
+        authType: AuthType?,
+        expectedBodyParams: Map<String, Any>? = null) =
+            wiremock.requestServerBuilderStep({
+                url equalTo expectedUrl
+                headers contains "User-Agent" like "vonage-java-sdk.*"
+                if (authType != null) {
+                    headers contains "Authorization" like when (authType) {
+                        AuthType.JWT -> "Bearer eyJ.+"
+                        AuthType.API_KEY_SECRET -> "Basic $apiKeySecretEncoded"
+                    }
+                }
+                if (contentType != null) {
+                    headers contains "Content-Type" equalTo contentType.mime
+                }
+                if (accept != null) {
+                    headers contains "Accept" equalTo accept.mime
+                }
+                if (expectedBodyParams != null) {
+                    body equalTo ObjectMapper().writeValueAsString(expectedBodyParams)
+                }
+            }, when (httpMethod) {
+                    HttpMethod.GET -> WireMock::get
+                    HttpMethod.POST -> WireMock::post
+                    HttpMethod.PUT -> WireMock::put
+                    HttpMethod.PATCH -> WireMock::patch
+                    HttpMethod.DELETE -> WireMock::delete
+                    else -> throw IllegalArgumentException("Unhandled HTTP method: $httpMethod")
+            })
 }
\ No newline at end of file
diff --git a/src/test/kotlin/com/vonage/client/kt/MessagesTest.kt b/src/test/kotlin/com/vonage/client/kt/MessagesTest.kt
index f5aa4a9..7e6f34e 100644
--- a/src/test/kotlin/com/vonage/client/kt/MessagesTest.kt
+++ b/src/test/kotlin/com/vonage/client/kt/MessagesTest.kt
@@ -2,6 +2,7 @@ package com.vonage.client.kt
 
 import com.fasterxml.jackson.databind.ObjectMapper
 import com.marcinziolo.kotlin.wiremock.*
+import com.vonage.client.common.HttpMethod
 import com.vonage.client.messages.Channel
 import com.vonage.client.messages.MessageRequest
 import com.vonage.client.messages.MessageResponseException
@@ -36,16 +37,10 @@ class MessagesTest : AbstractTest() {
     private val captionMap = mapOf("caption" to caption)
 
     private fun baseMockRequest(expectedBodyParams: Map<String, Any>? = null) =
-        wiremock.post {
-            url equalTo "/v1/messages"
-            headers contains "User-Agent" like "vonage-java-sdk.*"
-            headers contains "Authorization" like "Bearer eyJ.+"
-            headers contains "Content-Type" equalTo "application/json"
-            headers contains "Accept" equalTo "application/json"
-            if (expectedBodyParams != null) {
-                body equalTo ObjectMapper().writeValueAsString(expectedBodyParams)
-            }
-        }
+        baseMockRequest(HttpMethod.POST, "/v1/messages",
+            ContentType.APPLICATION_JSON, ContentType.APPLICATION_JSON,
+            AuthType.JWT, expectedBodyParams
+        )
 
     private fun mock202Response(expectedBodyParams: Map<String, Any>) {
         baseMockRequest(expectedBodyParams) returns {