Share the web workflow MDNS object with the user

Fixes #7369

Author: tannewt

shared-bindings/mdns/Server.c

@@ -33,6 +33,10 @@
 #include "shared-bindings/mdns/Server.h"
 #include "shared-bindings/util.h"
 
+#if CIRCUITPY_WEB_WORKFLOW
+#include "supervisor/shared/web_workflow/web_workflow.h"
+#endif
+
 //| class Server:
 //|     """The MDNS Server responds to queries for this device's information and allows for querying
 //|     other devices."""
@@ -53,6 +57,13 @@ STATIC mp_obj_t mdns_server_make_new(const mp_obj_type_t *type, size_t n_args, s
     mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
     mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
 
+    #if CIRCUITPY_WEB_WORKFLOW
+    mdns_server_obj_t *web_workflow_mdns = supervisor_web_workflow_mdns(args[ARG_network_interface].u_obj);
+    if (web_workflow_mdns != NULL) {
+        return web_workflow_mdns;
+    }
+    #endif
+
     mdns_server_obj_t *self = m_new_obj(mdns_server_obj_t);
     self->base.type = &mdns_server_type;
     common_hal_mdns_server_construct(self, args[ARG_network_interface].u_obj);

supervisor/shared/web_workflow/web_workflow.c

@@ -200,6 +200,15 @@ STATIC void _update_encoded_ip(void) {
     }
 }
 
+mdns_server_obj_t *supervisor_web_workflow_mdns(mp_obj_t network_interface) {
+    #if CIRCUITPY_MDNS
+    if (network_interface == &common_hal_wifi_radio_obj) {
+        return &mdns;
+    }
+    #endif
+    return NULL;
+}
+
 #if CIRCUITPY_STATUS_BAR
 bool supervisor_web_workflow_status_dirty(void) {
     return common_hal_wifi_radio_get_enabled(&common_hal_wifi_radio_obj) != _last_enabled ||

supervisor/shared/web_workflow/web_workflow.h

@@ -28,6 +28,7 @@
 
 #include <stdbool.h>
 
+#include "shared-bindings/mdns/Server.h"
 #include "shared-bindings/socketpool/Socket.h"
 
 // This background function should be called repeatedly. It cannot be done based
@@ -38,5 +39,8 @@ void supervisor_web_workflow_status(void);
 void supervisor_start_web_workflow(void);
 void supervisor_stop_web_workflow(void);
 
+// Share the MDNS object with user code.
+mdns_server_obj_t *supervisor_web_workflow_mdns(mp_obj_t network_interface);
+
 // To share with websocket.
 void web_workflow_send_raw(socketpool_socket_obj_t *socket, const uint8_t *buf, int len);