refactor: Strengthen multi-spec validation messages and tests

Author: thced

src/main/java/com/retailsvc/http/OpenApiServer.java

@@ -384,7 +384,7 @@ public Builder extraRoute(String path, RequestHandler handler) {
     }
 
     public OpenApiServer build() throws IOException {
-      boolean usedLegacy = spec != null || handlers != null;
+      boolean usedLegacy = spec != null || handlers != null || !securityValidators.isEmpty();
       boolean usedAddSpec = !bindings.isEmpty();
       if (usedLegacy && usedAddSpec) {
         throw new IllegalStateException(
@@ -425,7 +425,11 @@ public OpenApiServer build() throws IOException {
       for (String path : extras.keySet()) {
         if (seenBasePaths.containsKey(path)) {
           throw new IllegalStateException(
-              "extra handler path " + path + " conflicts with spec basePath " + path);
+              "extra handler path '"
+                  + path
+                  + "' conflicts with basePath of spec '"
+                  + seenBasePaths.get(path)
+                  + "'");
         }
       }
 

src/test/java/com/retailsvc/http/MultiSpecServerTest.java

@@ -32,8 +32,12 @@ void servesTwoBindingsOnDistinctBasePaths() throws Exception {
             .build()) {
 
       int port = server.listenPort();
-      assertThat(get("http://localhost:" + port + "/api/v1/data").statusCode()).isEqualTo(HTTP_OK);
-      assertThat(get("http://localhost:" + port + "/api/v2/data").statusCode()).isEqualTo(HTTP_OK);
+      HttpResponse<String> v1Resp = get("http://localhost:" + port + "/api/v1/data");
+      HttpResponse<String> v2Resp = get("http://localhost:" + port + "/api/v2/data");
+      assertThat(v1Resp.statusCode()).isEqualTo(HTTP_OK);
+      assertThat(v1Resp.body()).contains("v1");
+      assertThat(v2Resp.statusCode()).isEqualTo(HTTP_OK);
+      assertThat(v2Resp.body()).contains("v2");
     }
   }