DHT defaults to adding a namespaced pk and ipns validator unless the Validator has been changed, in which case neither of them are added. Simply adding additional NamespacedValidators does not remove the pk or ipns validators

Author: aschmahmann

dht.go

@@ -135,6 +135,9 @@ func New(ctx context.Context, h host.Host, options ...Option) (*IpfsDHT, error)
 	if err := cfg.apply(append([]Option{defaults}, options...)...); err != nil {
 		return nil, err
 	}
+	if err := cfg.applyFallbacks(h); err != nil {
+		return nil, err
+	}
 
 	if err := cfg.validate(); err != nil {
 		return nil, err

dht_options.go

@@ -72,13 +72,17 @@ func (c *config) apply(opts ...Option) error {
 
 // applyFallbacks sets default values that could not be applied during config creation since they are dependent
 // on other configuration parameters (e.g. optA is by default 2x optB) and/or on the Host
-func (c *config) applyFallbacks(h host.Host) {
+func (c *config) applyFallbacks(h host.Host) error {
 	if !c.validatorChanged {
-		c.validator = record.NamespacedValidator{
-			"pk":   record.PublicKeyValidator{},
-			"ipns": ipns.Validator{KeyBook: h.Peerstore()},
+		nsval, ok := c.validator.(record.NamespacedValidator)
+		if ok {
+			nsval["pk"] = record.PublicKeyValidator{}
+			nsval["ipns"] = ipns.Validator{KeyBook: h.Peerstore()}
+		} else {
+			return fmt.Errorf("the default validator was changed without being marked as changed")
 		}
 	}
+	return nil
 }
 
 // Option DHT option type.
@@ -89,6 +93,7 @@ const defaultBucketSize = 20
 // defaults are the default DHT options. This option will be automatically
 // prepended to any options you pass to the DHT constructor.
 var defaults = func(o *config) error {
+	o.validator = record.NamespacedValidator{}
 	o.datastore = dssync.MutexWrap(ds.NewMapDatastore())
 	o.protocolPrefix = DefaultPrefix
 	o.enableProviders = true
@@ -186,7 +191,7 @@ func Mode(m ModeOpt) Option {
 // Validator configures the DHT to use the specified validator.
 //
 // Defaults to a namespaced validator that can validate both public key (under the "pk"
-// namespaced) and IPNS records (under the "ipns" namespace). Setting the validator
+// namespace) and IPNS records (under the "ipns" namespace). Setting the validator
 // implies that the user wants to control the validators and therefore the default
 // public key and IPNS validators will not be added.
 func Validator(v record.Validator) Option {
@@ -198,32 +203,32 @@ func Validator(v record.Validator) Option {
 }
 
 // NamespacedValidator adds a validator namespaced under `ns`. This option fails
-// if the DHT is not using a `record.NamespacedValidator` as its validator. If
-// the validator has yet to be modified (e.g. by the `Validator` option) then
-// a NamespacedValidator will be created implicitly. Adding a namespaced
-// validator implies that the user wants to control the validators and therefore
-// the default public key and IPNS validators will not be added.
+// if the DHT is not using a `record.NamespacedValidator` as its validator (it
+// uses one by default but this can be overridden with the `Validator` option).
+// Adding a namespaced validator without changing the `Validator` will result in
+// adding a new validator in addition to the default public key and IPNS validators.
+// The "pk" and "ipns" namespaces cannot be overridden here unless a new `Validator`
+// has been set first.
 //
 // Example: Given a validator registered as `NamespacedValidator("ipns",
 // myValidator)`, all records with keys starting with `/ipns/` will be validated
 // with `myValidator`.
 func NamespacedValidator(ns string, v record.Validator) Option {
 	return func(c *config) error {
-		// while the validator will not change if there's an error setting the validator that is only possible
-		// if the validator has already been changed
-		c.validatorChanged = true
-
-		if c.validator == nil {
-			c.validator = record.NamespacedValidator{
-				ns: v,
+		if !c.validatorChanged {
+			if ns == "pk" {
+				return fmt.Errorf("cannot override the pk namespace without first changing the Validator")
 			}
-		} else {
-			nsval, ok := c.validator.(record.NamespacedValidator)
-			if !ok {
-				return fmt.Errorf("can only add namespaced validators to a NamespacedValidator")
+			if ns == "ipns" {
+				return fmt.Errorf("cannot override the ipns namespace without first changing the Validator")
 			}
-			nsval[ns] = v
 		}
+
+		nsval, ok := c.validator.(record.NamespacedValidator)
+		if !ok {
+			return fmt.Errorf("can only add namespaced validators to a NamespacedValidator")
+		}
+		nsval[ns] = v
 		return nil
 	}
 }