alibaba/nacos · error · JoranException

Could not open URL [{}].

Error message

Could not open URL [{}].

What it means

Error "Could not open URL [{}]." thrown in alibaba/nacos.

Source

Thrown at logger-adapter-impl/logback-adapter-12/src/main/java/com/alibaba/nacos/logger/adapter/logback12/NacosLogbackConfiguratorAdapterV1.java:83

     * @param url config url
     * @throws Exception e
     */
    public void configure(URL url) throws Exception {
        InputStream in = null;
        try {
            URLConnection urlConnection = url.openConnection();
            urlConnection.setUseCaches(false);
            in = urlConnection.getInputStream();
            if (hasNewDoConfigureApi()) {
                doConfigure(in, url.toExternalForm());
            } else {
                // adapter old version of logback below 1.1.10
                doConfigure(in);
            }
        } catch (IOException ioe) {
            String errMsg = "Could not open URL [" + url + "].";
            addError(errMsg, ioe);
            throw new JoranException(errMsg, ioe);
        } finally {
            if (in != null) {
                try {
                    in.close();
                } catch (IOException ioe) {
                    String errMsg = "Could not close input stream";
                    addError(errMsg, ioe);
                    throw new JoranException(errMsg, ioe);
                }
            }
        }
    }
    
    /**
     * Since logback 1.1.10, Add new doConfigure API with sax systemId and use this API to do configure.
     *
     * @return {@code true} when logback is upper 1.1.10, otherwise {@code false}
     */

View on GitHub (pinned to 9b989acdf1)

Solutions

1. Review the input and runtime state for logback config URL open failed, correct the reported problem, and retry.

When it happens

Trigger: Thrown at logger-adapter-impl/logback-adapter-12/src/main/java/com/alibaba/nacos/logger/adapter/logback12/NacosLogbackConfiguratorAdapterV1.java:83 when the library encounters an invalid state.

Common situations: Opening the Logback configuration URL failed.

AI-assisted analysis of alibaba/nacos@9b989acdf1 (2026-08-14). Data as JSON: /api/errors/e41657a057c3a255. Report an issue: GitHub.