Base url that works everywhere in mocks

src/lib/BASE_URL.ts

@@ -0,0 +1,41 @@
+import { assert } from "tsafe/assert";
+
+/**
+ * WARNING: Internal use only!!
+ * This is just a way to know what's the base url that works
+ * both in webpack and vite.
+ * THIS DOES NOT WORK IN KEYCLOAK! It's only for resolving mock assets.
+ */
+export const BASE_URL = (() => {
+    vite: {
+        let BASE_URL: string;
+
+        try {
+            // @ts-expect-error
+            BASE_URL = import.meta.env.BASE_URL;
+
+            assert(typeof BASE_URL === "string");
+        } catch {
+            break vite;
+        }
+
+        return BASE_URL;
+    }
+
+    webpack: {
+        let BASE_URL: string;
+
+        try {
+            // @ts-expect-error
+            BASE_URL = process.env.PUBLIC_URL;
+
+            assert(typeof BASE_URL === "string");
+        } catch {
+            break webpack;
+        }
+
+        return BASE_URL === "" ? "/" : `${BASE_URL}/`;
+    }
+
+    return "/";
+})();