usebruno/bruno · error · TypeError

minifyXml expects a string

Error message

minifyXml expects a string

What it means

Thrown as a TypeError by bru.utils.minifyXml when the input is not a string and not null/undefined. The function accepts only strings (and rejects null/undefined with 'Failed to minify'); any other type (number, boolean, object, symbol) falls through to the TypeError at bru.js:138.

Source

Thrown at packages/bruno-js/src/bru.js:138

        }

        throw new TypeError('minifyJson expects a string or object');
      },

      minifyXml: (xml) => {
        if (xml === null || xml === undefined) {
          throw new Error('Failed to minify');
        }

        if (typeof xml === 'string') {
          try {
            return xmlFormat(xml, { collapseContent: false, indentation: '', lineSeparator: '' });
          } catch (err) {
            throw new Error(`Failed to minify: ${err?.message || err}`);
          }
        }

        throw new TypeError('minifyXml expects a string');
      }
    };
  }

  interpolate = (strOrObj) => {
    if (!strOrObj) return strOrObj;
    const isObj = typeof strOrObj === 'object';
    const strToInterpolate = isObj ? JSON.stringify(strOrObj) : strOrObj;

    const combinedVars = {
      ...this.globalEnvironmentVariables,
      ...this.collectionVariables,
      ...this.envVariables,
      ...this.folderVariables,
      ...this.requestVariables,
      ...this.oauth2CredentialVariables,
      ...this.runtimeVariables,
      ...this.promptVariables,

View on GitHub (pinned to 9bdd81c7bd)

Solutions

1. Ensure the input is a string; if it is an object, serialize it first.
2. Check typeof xml === 'string' before calling minifyXml.
3. If you have a DOM object, call its serialize method (e.g., XMLSerializer) to get a string first.

Example fix

// before
const min = bru.utils.minifyXml(res.getBody()); // returns an object, not a string

// after
const body = res.getBody();
const xmlStr = typeof body === 'string' ? body : JSON.stringify(body);
const min = bru.utils.minifyXml(xmlStr);

function isStringInput(val) {
  return typeof val === 'string';
}
// before calling: if (isStringInput(val)) bru.utils.minifyXml(val);

function isMinifiableXmlInput(val) {
  return typeof val === 'string';
}

When it happens

Trigger: Calling bru.utils.minifyXml(42), bru.utils.minifyXml(true), bru.utils.minifyXml({ root: 'data' }), or bru.utils.minifyXml(() => {}). The typeof xml check at bru.js:130 only matches 'string'.

Common situations: Passing a parsed XML DOM object instead of the serialized XML string. Passing a numeric status code or boolean flag by mistake. Passing a response body object when the raw string was intended.

Related errors

• minifyJson expects a string or object
• ${callback} is not a function
• Invalid arguments passed to setCookie
• setCookies expects an array of cookie objects
• Workspace path not found

AI-assisted analysis of usebruno/bruno@9bdd81c7bd (2026-08-13). Data as JSON: /api/errors/3be297a7c41add93. Report an issue: GitHub.