alibaba/nacos · error · IllegalArgumentException

Plugin config value is not a number: + key

Error message

Plugin config value is not a number:  + key

What it means

Thrown by parsePositiveLong() in NacosAuthPluginConfig when the token.expire.seconds value cannot be parsed as a long (Long.parseLong throws NumberFormatException). The NumberFormatException is caught and rethrown as an IllegalArgumentException naming the offending key.

Source

Thrown at plugin-default-impl/nacos-default-auth-plugin/src/main/java/com/alibaba/nacos/plugin/auth/impl/configuration/NacosAuthPluginConfig.java:129

        if (config == null || !config.containsKey(key)) {
            return defaultValue;
        }
        String result = config.get(key);
        if (result == null) {
            throw new IllegalArgumentException("Plugin config value cannot be null: " + key);
        }
        return result;
    }
    
    private static long parsePositiveLong(String value, String key) {
        try {
            long result = Long.parseLong(value);
            if (result <= 0) {
                throw new IllegalArgumentException("Plugin config value must be positive: " + key);
            }
            return result;
        } catch (NumberFormatException e) {
            throw new IllegalArgumentException("Plugin config value is not a number: " + key, e);
        }
    }
    
    private static boolean parseBoolean(String value, String key) {
        if (!Boolean.TRUE.toString().equalsIgnoreCase(value)
            && !Boolean.FALSE.toString().equalsIgnoreCase(value)) {
            throw new IllegalArgumentException("Plugin config value is not a boolean: " + key);
        }
        return Boolean.parseBoolean(value);
    }
    
    private static void validateTokenSecret(String tokenSecretKey) {
        if (StringUtils.isBlank(tokenSecretKey)) {
            return;
        }
        try {
            new NacosJwtParser(tokenSecretKey);
        } catch (RuntimeException e) {

View on GitHub (pinned to 9b989acdf1)

Solutions

1. Set token.expire.seconds to a plain integer (seconds), e.g., 18000.
2. Remove any unit suffixes, commas, or whitespace from the value.
3. If unset, remove the key so the default applies.

Example fix

// before
nacos.core.auth.plugin.nacos.token.expire.seconds=5h

// after
nacos.core.auth.plugin.nacos.token.expire.seconds=18000

String raw = config.get(NacosAuthPluginConfig.TOKEN_EXPIRE_SECONDS);
if (raw != null && !raw.matches("\\d+")) {
    throw new IllegalArgumentException("token.expire.seconds must be a plain integer, got: " + raw);
}

When it happens

Trigger: nacos.core.auth.plugin.nacos.token.expire.seconds is set to a non-numeric string (e.g., '5h', 'abc', '18,000'); parsePositiveLong() hits the catch (NumberFormatException) branch.

Common situations: Using a human-readable duration string ('5h', '30m') where a raw integer is required; locale-specific number formatting with a comma; a typo or trailing whitespace/unit suffix.

Related errors

• Plugin config value must be positive: + key
• Base directory cannot be blank
• listener is null
• dataId={dataId}, group={group}
• 10000

AI-assisted analysis of alibaba/nacos@9b989acdf1 (2026-08-14). Data as JSON: /api/errors/000d309292cd7f8d. Report an issue: GitHub.