projectdiscovery/nuclei · error

ExportAs expects 2 arguments

Error message

ExportAs expects 2 arguments

What it means

A JavaScript (code protocol) template called the registered helper ExportAs with an argument count other than 2. The binding registered on the goja runtime explicitly panics with this message when len(call.Arguments) != 2; goja converts that panic into a JS exception, aborting template compilation/execution. The expected signature is ExportAs(key string, value any).

Source

Thrown at pkg/js/compiler/pool.go:195

			}
			for _, arg := range call.Arguments {
				if out := stringify(arg, runtime); out != "" {
					buff.WriteString(out)
				}
			}
			return goja.Null()
		},
	})
	// register exportAs function
	_ = gojs.RegisterFuncWithSignature(runtime, gojs.FuncOpts{
		Name:        "ExportAs", // Export
		Signatures:  []string{"ExportAs(key string,value any)"},
		Description: "Exports given value with specified key and makes it available in DSL and response",
		FuncDecl: func(call goja.FunctionCall, runtime *goja.Runtime) goja.Value {
			if len(call.Arguments) != 2 {
				// this is how goja expects errors to be returned
				// and internally it is done same way for all errors
				panic(runtime.ToValue("ExportAs expects 2 arguments"))
			}
			key := call.Argument(0).String()
			value := call.Argument(1)
			opts.exports[key] = stringify(value, runtime)
			return goja.Null()
		},
	})
}

// Internal purposes i.e generating bindings
func InternalGetGeneratorRuntime() *goja.Runtime {
	runtime := gojapool.Get().(*goja.Runtime)
	return runtime
}

func enableRequire(runtime *goja.Runtime) {
	lazyRegistryInit()
	_ = require.NewRegistry(require.WithLoader(newSourceLoader(runtime))).Enable(runtime)

View on GitHub (pinned to 265b3a3dec)

Solutions

1. Call ExportAs with exactly two arguments: a string key and any value, e.g. ExportAs('extracted', value).
2. Lint template JS early — a syntax/arity check via the code protocol compile step (template-validate) catches it before a scan run.
3. If you meant to export several values, issue one ExportAs call per key/value pair.

Example fix

// before
ExportAs('token'); // -> ExportAs expects 2 arguments

// after
ExportAs('token', extractedValue);

// in template JS: keep the arity check on your side
if (typeof key === 'string' && value !== undefined) {
    ExportAs(key, value);
}

// JS guard before calling
const exportAs = (k, v) => { if (arguments.length !== 2) throw new TypeError('ExportAs(key, value)'); ExportAs(k, v); };

try { ExportAs('k', v); } catch (e) { if (String(e).includes('expects 2 arguments')) { /* fix call site arity */ } }

When it happens

Trigger: Template JS calling ExportAs('k') with no value, ExportAs() with nothing, or ExportAs('k', v, extra); also passing extra undefined trailing arguments, since goja counts supplied arguments.

Common situations: Hand-writing code-protocol templates and forgetting the value; refactoring a helper into ExportAs and leaving an old single-argument call; copy-paste from examples that used a different export API.

Related errors

• panic: %s
• nuclei js runtime: program failed to terminate after interru
• invalid TicketRequest: %w
• invalid ASRepRoastRequest: %w
• invalid KerberoastRequest: %w

AI-assisted analysis of projectdiscovery/nuclei@265b3a3dec (2026-08-15). Data as JSON: /api/errors/7c1df54fc58bfc86. Report an issue: GitHub.