Enable Magento 1.* API on Byte Hypernode - nginx rewrite configuration. Typically, you would place this in server.rewrites or public.rewrites. See https://support.hypernode.com/knowledgebase/rewriting-and-redirecting-urls-in-nginx/

enable_magento_api_on_hypernode.rewrites

# Enable Magento 1.* API on Byte Hypernode
# Rewrite is piped through phpfpm, or the api.php is not run through PHP interpreter.
location /api {
    rewrite ^/api/rest /api.php?type=rest last;

    location ~ \.php$ {
        echo_exec @phpfpm;
    }
}