2 files changed, 34 insertions, 0 deletions
diff --git a/runtime/web_worker.rs b/runtime/web_worker.rs
index 11bcd328a..de32e3994 100644
--- a/runtime/web_worker.rs
+++ b/runtime/web_worker.rs
@@ -6,6 +6,7 @@ use crate::permissions::PermissionsContainer;
 use crate::shared::runtime;
 use crate::tokio_util::create_and_run_current_thread;
 use crate::worker::import_meta_resolve_callback;
+use crate::worker::validate_import_attributes_callback;
 use crate::worker::FormatJsErrorFn;
 use crate::BootstrapOptions;
 use deno_broadcast_channel::InMemoryBroadcastChannel;
@@ -547,6 +548,9 @@ impl WebWorker {
       import_meta_resolve_callback: Some(Box::new(
         import_meta_resolve_callback,
       )),
+      validate_import_attributes_cb: Some(Box::new(
+        validate_import_attributes_callback,
+      )),
       ..Default::default()
     });
 
diff --git a/runtime/worker.rs b/runtime/worker.rs
index 1fac28c6a..2cb1ab491 100644
--- a/runtime/worker.rs
+++ b/runtime/worker.rs
@@ -1,4 +1,5 @@
 // Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
+use std::collections::HashMap;
 use std::rc::Rc;
 use std::sync::atomic::AtomicBool;
 use std::sync::atomic::AtomicI32;
@@ -62,6 +63,32 @@ pub fn import_meta_resolve_callback(
   )
 }
 
+// TODO(bartlomieju): temporary measurement until we start supporting more
+// module types
+pub fn validate_import_attributes_callback(
+  scope: &mut v8::HandleScope,
+  attributes: &HashMap<String, String>,
+) {
+  for (key, value) in attributes {
+    let msg = if key != "type" {
+      Some(format!("\"{key}\" attribute is not supported."))
+    } else if value != "json" {
+      Some(format!("\"{value}\" is not a valid module type."))
+    } else {
+      None
+    };
+
+    let Some(msg) = msg else {
+      continue;
+    };
+
+    let message = v8::String::new(scope, &msg).unwrap();
+    let exception = v8::Exception::type_error(scope, message);
+    scope.throw_exception(exception);
+    return;
+  }
+}
+
 #[derive(Clone, Default)]
 pub struct ExitCode(Arc<AtomicI32>);
 
@@ -469,6 +496,9 @@ impl MainWorker {
       import_meta_resolve_callback: Some(Box::new(
         import_meta_resolve_callback,
       )),
+      validate_import_attributes_cb: Some(Box::new(
+        validate_import_attributes_callback,
+      )),
       ..Default::default()
     });