Handle subscription update for eKuiper and MQTT plugin

plugins/ekuiper/plugin_ekuiper.c

@@ -308,7 +308,8 @@ static int ekuiper_plugin_request(neu_plugin_t *      plugin,
         send_data(plugin, trans_data);
         break;
     }
-    case NEU_REQ_SUBSCRIBE_GROUP: {
+    case NEU_REQ_SUBSCRIBE_GROUP:
+    case NEU_REQ_UPDATE_SUBSCRIBE_GROUP: {
         neu_req_subscribe_t *sub_info = data;
         free(sub_info->params);
         break;

plugins/mqtt/mqtt_handle.c

@@ -587,6 +587,7 @@ int handle_subscribe_group(neu_plugin_t *plugin, neu_req_subscribe_t *sub_info)
         // no parameters, try default topic
         topic.v.val_str = default_upload_topic(sub_info);
         if (NULL == topic.v.val_str) {
+            rv = NEU_ERR_EINTERNAL;
             goto end;
         }
     } else if (0 != neu_parse_param(sub_info->params, NULL, 1, &topic)) {
@@ -599,9 +600,41 @@ int handle_subscribe_group(neu_plugin_t *plugin, neu_req_subscribe_t *sub_info)
                            sub_info->group, topic.v.val_str);
     // topic.v.val_str ownership moved
     if (0 != rv) {
-        plog_error(plugin, "route driver:%s group:%s to topic:%s fail, `%s`",
-                   sub_info->driver, sub_info->group, topic.v.val_str,
-                   sub_info->params);
+        plog_error(plugin, "route driver:%s group:%s fail, `%s`",
+                   sub_info->driver, sub_info->group, sub_info->params);
+        goto end;
+    }
+
+    plog_notice(plugin, "route driver:%s group:%s to topic:%s",
+                sub_info->driver, sub_info->group, topic.v.val_str);
+
+end:
+    free(sub_info->params);
+    return rv;
+}
+
+int handle_update_subscribe(neu_plugin_t *plugin, neu_req_subscribe_t *sub_info)
+{
+    int rv = 0;
+
+    if (NULL == sub_info->params) {
+        rv = NEU_ERR_GROUP_PARAMETER_INVALID;
+        goto end;
+    }
+
+    neu_json_elem_t topic = { .name = "topic", .t = NEU_JSON_STR };
+    if (0 != neu_parse_param(sub_info->params, NULL, 1, &topic)) {
+        plog_error(plugin, "parse `%s` for topic fail", sub_info->params);
+        rv = NEU_ERR_GROUP_PARAMETER_INVALID;
+        goto end;
+    }
+
+    rv = route_tbl_update(&plugin->route_tbl, sub_info->driver, sub_info->group,
+                          topic.v.val_str);
+    // topic.v.val_str ownership moved
+    if (0 != rv) {
+        plog_error(plugin, "route driver:%s group:%s fail, `%s`",
+                   sub_info->driver, sub_info->group, sub_info->params);
         goto end;
     }
 

plugins/mqtt/mqtt_handle.h

@@ -43,6 +43,8 @@ int handle_trans_data(neu_plugin_t *            plugin,
                       neu_reqresp_trans_data_t *trans_data);
 
 int handle_subscribe_group(neu_plugin_t *plugin, neu_req_subscribe_t *sub_info);
+int handle_update_subscribe(neu_plugin_t *       plugin,
+                            neu_req_subscribe_t *sub_info);
 int handle_unsubscribe_group(neu_plugin_t *         plugin,
                              neu_req_unsubscribe_t *unsub_info);
 

plugins/mqtt/mqtt_plugin.c

@@ -350,6 +350,9 @@ static int mqtt_plugin_request(neu_plugin_t *plugin, neu_reqresp_head_t *head,
     case NEU_REQ_SUBSCRIBE_GROUP:
         error = handle_subscribe_group(plugin, data);
         break;
+    case NEU_REQ_UPDATE_SUBSCRIBE_GROUP:
+        error = handle_update_subscribe(plugin, data);
+        break;
     case NEU_REQ_UNSUBSCRIBE_GROUP:
         error = handle_unsubscribe_group(plugin, data);
         break;

plugins/mqtt/mqtt_plugin.h

@@ -107,6 +107,24 @@ static inline int route_tbl_add_new(route_entry_t **tbl, const char *driver,
     return 0;
 }
 
+// NOTE: we take ownership of `topic`
+static inline int route_tbl_update(route_entry_t **tbl, const char *driver,
+                                   const char *group, char *topic)
+{
+    route_entry_t *find = NULL;
+
+    find = route_tbl_get(tbl, driver, group);
+    if (NULL == find) {
+        free(topic);
+        return NEU_ERR_GROUP_NOT_SUBSCRIBE;
+    }
+
+    free(find->topic);
+    find->topic = topic;
+
+    return 0;
+}
+
 static inline void route_tbl_del(route_entry_t **tbl, const char *driver,
                                  const char *group)
 {

src/core/subscribe.c

@@ -239,8 +239,8 @@ int neu_subscribe_manager_update_params(neu_subscribe_mgr_t *mgr,
         return NEU_ERR_GROUP_NOT_SUBSCRIBE;
     }
 
-    char *p = strdup(params);
-    if (NULL == p) {
+    char *p = NULL;
+    if (params && NULL == (p = strdup(params))) {
         return NEU_ERR_EINTERNAL;
     }