gchq/CyberChef · error · TypeError

flowControl operations like

Error message

flowControl operations like ${ing.opName} are not currently allowed in recipes for chef.bake in the Node API

What it means

Thrown by NodeRecipe._validateIngredient when the ingredient is a function (an operation class) but its flowControl flag is set. The Node API deliberately excludes flow-control operations (Fork, Magic, etc.) from chef.bake recipes because they manipulate the recipe graph itself, which the Node execution model does not support.

Solutions

  1. Remove the flowControl operation from the Node recipe.
  2. Reimplement its effect with a script or a different sequence of supported operations.
  3. For Magic-style detection, run candidate recipes yourself instead of using the Magic op.

Example fix

// before
chef.bake(input, [Fork, "From Hex"]); // Fork is flowControl
// after
chef.bake(input, ["From Hex"]);
Defensive patterns

Strategy: validation

Validate before calling

function assertNoFlowControl(recipe) {
  for (const ing of recipe) if (typeof ing === "function" && ing.flowControl) throw new Error(`${ing.opName} is flowControl and unsupported in Node`);
}

Type guard

const isFlowControl = (ing) => typeof ing === "function" && ing.flowControl === true;

Try / catch

try { chef.bake(input, recipe); } catch (e) { if (e instanceof TypeError && /flowControl operations/.test(e.message)) { /* remove op */ } else throw e; }

Prevention

When it happens

Trigger: A recipe includes a flowControl operation passed as a function reference (e.g. chef.operations.Fork or the imported operation class). The check is ing.flowControl === true at validation time.

Common situations: Porting a browser recipe that uses Fork/Magic/Register/Label to the Node API; importing operations directly from src and adding them to a recipe array.

Related errors

AI-assisted analysis of gchq/CyberChef@4290ea7539 (2026-08-13). Data as JSON: /api/errors/d3e8d33c4ef90cea. Report an issue: GitHub.

Appendix: source

Thrown at src/node/NodeRecipe.mjs:48

     *  operation and its arguments
     * @throws {TypeError} If it cannot find the operation in chef's list of operations.
     */
    _validateIngredient(ing) {
        // CASE operation name given. Find operation and validate
        if (typeof ing === "string") {
            const op = operations.find((op) => {
                return sanitise(op.opName) === sanitise(ing);
            });
            if (op) {
                // Need to validate against case 2
                return this._validateIngredient(op);
            } else {
                throw new TypeError(`Couldn't find an operation with name '${ing}'.`);
            }
        // CASE operation given. Check its a chef operation and check its not flowcontrol
        } else if (typeof ing === "function") {
            if (ing.flowControl) {
                throw new TypeError(`flowControl operations like ${ing.opName} are not currently allowed in recipes for chef.bake in the Node API`);
            }

            if (operations.includes(ing)) {
                return ing;
            } else {
                throw new TypeError("Inputted function not a Chef operation.");
            }
        // CASE: op, maybe with configuration
        } else if (ing.op) {
            const sanitisedOp = this._validateIngredient(ing.op);
            if (ing.args) {
                return {op: sanitisedOp, args: ing.args};
            }
            return sanitisedOp;
        } else {
            throw new TypeError("Recipe can only contain function names or functions");
        }
    }

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