@PostMapping("/{namespaceId}/{pluginId}")
    @RequiresPermissions("system:plugin:edit")
    public ShenyuAdminResult generateNamespacePlugin(@Existed(message = "namespace is not exist", provider = NamespaceMapper.class)
                                          @PathVariable("namespaceId") final String namespaceId,
                                       @Existed(message = "plugin is not exist", provider = PluginMapper.class)
                                       @PathVariable("pluginId") final String pluginId) {
        return ShenyuAdminResult.success(namespacePluginService.create(namespaceId, pluginId));
    }
add plugin of namespace.

@param namespaceId        namespaceId.
@param pluginId           pluginId.
@return {@linkplain ShenyuAdminResult}
shenyu-admin/src/main/java/org/apache/shenyu/admin/controller/NamespacePluginController.java