alibaba/nacos · error · NacosException

400

400

Error message

tagv2 gray rule parse failed: key and value's[%s] doesn't match pattern[%s].

What it means

Thrown by MultiTagMatchGrayRule.parse when a sub-expression (after splitting on || and &&) does not contain exactly one '=' separator (keyValueArray.length != 2). Returns NacosException code 400 (INVALID_PARAM). This is a structural error in a multi-tag gray rule expression, distinct from the regex-pattern error 834.

Source

Thrown at config/src/main/java/com/alibaba/nacos/config/server/model/gray/multitag/MultiTagMatchGrayRule.java:82

    protected void parse(String rawRule) throws NacosException {
        this.isPatternMatch(rawRule, EXPRESSION_PATTERN);
        String[] splitSubExpressionByOrArray = rawRule.trim()
            .split(MultiTagMatchGrayRule.TagV2GrayRuleJoint.OR_REGEXP.getExpression());
        for (String s : splitSubExpressionByOrArray) {
            if (StringUtils.isBlank(s)) {
                continue;
            }
            //each subExpression is jointed by one or multi "&&"
            String[] splitSubExpressionByAndArray = s.trim()
                .split(MultiTagMatchGrayRule.TagV2GrayRuleJoint.AND_REGEXP.getExpression());
            for (int andIndex = 0; andIndex < splitSubExpressionByAndArray.length; andIndex++) {
                if (StringUtils.isBlank(splitSubExpressionByAndArray[andIndex])) {
                    continue;
                }
                String[] keyValueArray =
                    splitSubExpressionByAndArray[andIndex].trim().split(EQUAL_PATTERN);
                if (keyValueArray.length != 2) {
                    throw new NacosException(NacosException.INVALID_PARAM, String.format(
                        "tagv2 gray rule parse failed: key and value's[%s] doesn't match pattern[%s].",
                        splitSubExpressionByAndArray[andIndex],
                        KEY_PATTERN + EQUAL_PATTERN + VALUE_PATTERN));
                }
                isPatternMatch(keyValueArray[0].trim(), KEY_PATTERN);
                isPatternMatch(keyValueArray[1].trim(), VALUE_PATTERN);
                Set<String> values =
                    Arrays.stream(keyValueArray[1].split(VALUE_SPLITER_PATTERN)).map(String::trim)
                        .filter(StringUtils::isNotBlank).collect(Collectors.toSet());
                MultiTagMatchGrayRule.TagV2GrayRuleItem tagV2GrayRuleItem =
                    new MultiTagMatchGrayRule.TagV2GrayRuleItem(
                        keyValueArray[0].trim(), values);
                if (andIndex == 0) {
                    tagV2GrayRuleItem.setJoint(MultiTagMatchGrayRule.TagV2GrayRuleJoint.OR);
                }
                if (this.ruleItems == null) {
                    this.ruleItems = new ArrayList<>();
                }

View on GitHub (pinned to 9b989acdf1)

Solutions

Ensure every key=value segment in the multi-tag expression has exactly one '='.
Join multiple conditions with '&&' (AND) or '||' (OR), and separate values within a key with commas.

Example fix

// before
grayRuleExp = "zone&&env=prod"  // 'zone' has no value
// after
grayRuleExp = "zone=us-east-1&&env=prod"

Defensive patterns

Strategy: validation

Validate before calling

// Validate multi-tag rule: each segment must have exactly one '='
for (String seg : grayRuleExp.split("\\|\\||&&")) {
    seg = seg.trim();
    if (seg.isEmpty()) continue;
    String[] kv = seg.split("=", -1);
    if (kv.length != 2) throw new IllegalArgumentException("bad segment: " + seg);
}

Try / catch

try { configApi.publishGray(form); }
catch (NacosException e) {
    if (e.getErrCode() == NacosException.INVALID_PARAM)
        { /* each segment needs exactly one '=' */ } else throw e;
}

Prevention

Ensure each key=value segment in multi-tag rules has exactly one '='.
Join segments with && or ||, values with commas.

When it happens

Trigger: Submitting a multi-tag grayRuleExp where one segment has no '=' (e.g. 'keyonly&&k2=v2') or more than one '=' (e.g. 'a=b=c'). The overall EXPRESSION_PATTERN may pass but the split-by-'=' produces != 2 parts.

Common situations: Building complex multi-tag expressions programmatically with a missing or duplicated '='; concatenating keys without values; using '==' or '!=' instead of '='.

Related errors

AI-assisted analysis of alibaba/nacos@9b989acdf1 (2026-08-14). Data as JSON: /api/errors/c73824adbd8754f4. Report an issue: GitHub.