t8y2/dbx · error

definition is required

Error message

definition is required

What it means

setPolicy requires a definition object containing the policy settings (e.g. ha-mode, max-length, alternate-exchange). The library throws this when the definition param is absent or null, since a policy with no definition is meaningless to the RabbitMQ management API.

Source

Thrown at agents/drivers/rabbitmq/operations.go:1059

	}
}

func (s *server) setPolicy(params jsonObject) (any, error) {
	vhost, err := permissionVhost(params)
	if err != nil {
		return nil, err
	}
	name, err := policyName(params)
	if err != nil {
		return nil, err
	}
	pattern := stringOrEmpty(params, "pattern")
	if strings.TrimSpace(pattern) == "" {
		return nil, errors.New("pattern is required")
	}
	definition := objectOrNil(params, "definition")
	if definition == nil {
		return nil, errors.New("definition is required")
	}
	connection, err := s.requireConnectionConfig(params)
	if err != nil {
		return nil, err
	}
	body := jsonObject{
		"pattern":    pattern,
		"apply-to":   stringOrDefault(params, "applyTo", "queues"),
		"priority":   intOrDefault(params, "priority", 0),
		"definition": definition,
	}
	if _, err := managementSend(connection, http.MethodPut,
		"/api/policies/"+urlEncodeVhost(vhost)+"/"+urlEncodePathSegment(name), body); err != nil {
		return nil, err
	}
	return okResult(), nil
}

View on GitHub (pinned to c0390bff16)

Solutions

1. Pass definition as a JSON object, e.g. {"ha-mode":"all"} or {"max-length":10000}
2. Ensure the value is an object, not a JSON-encoded string
3. Validate with typeof/is-map before calling

Example fix

// before
{ "op": "setPolicy", "name": "ha", "pattern": ".*" }
// after
{ "op": "setPolicy", "name": "ha", "pattern": ".*", "definition": { "ha-mode": "all" } }

if (!params.definition || typeof params.definition !== "object") throw new Error("definition is required");

function hasDefinition(p) { return p.definition != null && typeof p.definition === "object" && !Array.isArray(p.definition); }

try { await agent.dispatch("setPolicy", params); } catch (e) { if (/definition is required/.test(e.message)) { /* supply policy definition object and retry */ } else throw e; }

When it happens

Trigger: Dispatching setPolicy with name and pattern but without definition, or definition explicitly null/undefined.

Common situations: Building params dynamically where definition JSON failed to parse; forgetting the object wrapper (passing a string); partial automation scripts updated to add pattern but not definition.

Understand the failure class

Background: Missing required parameter errors: what 'X is required' and 'the required X param is missing' mean, and how to fix them — this error's family across 27 libraries.

Related errors

• pattern is required
• virtual_host is required
• all_vhosts is only supported for list operations
• user name is required
• Not connected. Call connect first.

AI-assisted analysis of t8y2/dbx@c0390bff16 (2026-09-05). Data as JSON: /api/errors/9ff12c1bf797a70b. Report an issue: GitHub.