What causes "capabilities not passed in init" in hyperledger/fabric?

Supply the channel Capabilities object (typically from the channelconfig/capabilities provider) to Init()

capabilities not passed in init

Error message

capabilities not passed in init

What it means

Init() returns this error when the capabilities dependency is nil. The validator consults the channel capabilities (e.g. whether collection config upgrades, key-level validation, or v1.2+ features are enabled) to decide which validation paths to apply. Without capabilities it cannot validate safely and refuses to start.

Source

Thrown at core/handlers/validation/builtin/default_validation.go:134

		}
		if stateFetcher, isStateFetcher := dep.(vs.StateFetcher); isStateFetcher {
			sf = stateFetcher
		}
		if policyEvaluator, isPolicyFetcher := dep.(vp.PolicyEvaluator); isPolicyFetcher {
			pe = policyEvaluator
		}
		if collectionResources, isCollectionResources := dep.(plugindispatcher.CollectionResources); isCollectionResources {
			cor = collectionResources
		}
	}
	if sf == nil {
		return errors.New("stateFetcher not passed in init")
	}
	if d == nil {
		return errors.New("identityDeserializer not passed in init")
	}
	if c == nil {
		return errors.New("capabilities not passed in init")
	}
	if pe == nil {
		return errors.New("policy fetcher not passed in init")
	}
	if cor == nil {
		return errors.New("collection resources not passed in init")
	}

	v.Capabilities = c
	v.TxValidatorV1_2 = v12.New(c, sf, d, pe)
	v.TxValidatorV1_3 = v13.New(c, sf, d, pe)
	v.TxValidatorV2_0 = v20.New(c, sf, d, pe, cor)

	return nil
}

View on GitHub (pinned to 2736b63f8f)

Solutions

Supply the channel Capabilities object (typically from the channelconfig/capabilities provider) to Init()
Check that dependency assembly for validation handlers includes all five required deps (sf, d, c, pe, cor)
Update custom plugin code after version upgrades so new required dependencies are provided

Example fix

// before
err := handler.Init(sf, deserializer, nil, policyEvaluator, collectionResources)
// after
caps := channelconfig.NewApplicationCapabilities(...)
err := handler.Init(sf, deserializer, caps, policyEvaluator, collectionResources)

Defensive patterns

Strategy: validation

Validate before calling

if c == nil {
    return errors.New("cannot init validation handler: Capabilities dependency is nil")
}
err := handler.Init(sf, d, c, pe, cor)

Type guard

func depsComplete(c Capabilities) bool { return c != nil }

Prevention

Fetch channel capabilities from the channel config before creating validators
Update custom plugins when new versions add required dependencies
Verify Init is called only after channelconfig is loaded

When it happens

Trigger: Calling Init() with c == nil: constructing the built-in validation handler without a Capabilities provider in the dependency map.

Common situations: Hand-rolled plugin constructors omitting channel capabilities; peers created before capabilities were wired in newer versions; test harnesses with incomplete dependency stubs.

Related errors

AI-assisted analysis of hyperledger/fabric@2736b63f8f (2026-09-04). Data as JSON: /api/errors/1a32c5cd306a1b37. Report an issue: GitHub.