Merge pull request 'Distribution and the forge hold their caller list from its config watch, not an ask per call (issue 1966; group with mesh-sdk)' (#646) from fix/1966-callers-config-read into main

modules/distribution/cmd/distribution-tools/contract_test.go

@@ -57,7 +57,7 @@ func TestTheVerbsSpeakTheSeatsContract(t *testing.T) {
 			t.Errorf("%s's body %s is not the contract's: %v", event, b, err)
 		}
 	}
-	// The caller list is read on each call: one that cannot be read answers no verb, and registry_callers says it as read.
+	// The caller list is read held: one never read answers no verb, and registry_callers says it as read.
 	unread := func() (holder.Callers, error) { return nil, errors.New("config refused") }
 	for _, tool := range tools(&holder.Verbs{}, kept[holder.Window]{}, unread) {
 		if tool.Name == holder.ImageSeat+"."+holder.VerbVersions {

modules/distribution/cmd/distribution-tools/main.go

@@ -248,7 +248,7 @@ func arg[T any](args map[string]any) (T, error) {
 
 func str(args map[string]any, k string) string { s, _ := args[k].(string); return strings.TrimSpace(s) }
 
-// tools are distribution's tools over v; each call that checks a caller reads the caller list on that call (callers:
+// tools are distribution's tools over v; each call that checks a caller reads the caller list held (callers:
 // the config value as mesh-config resolves it now), so an operator's change of it holds from the next call on.
 func tools(v *holder.Verbs, windows kept[holder.Window], callers func() (holder.Callers, error)) []stdio.Tool {
 	now := func() (*holder.Verbs, error) {

modules/distribution/internal/holder/callers.go

@@ -93,11 +93,15 @@ func ParseCallers(raw string) (Callers, error) {
 	return selfNotReleasing(c)
 }
 
-// ConfiguredCallers is the config value `callers` as mesh-config resolved it for this machine, read through the tools
-// runtime's stdio.Config on each call (never an environment variable: nothing renders a config value into a
-// program's environment); unset is DefaultCallers, and Self on release's list is refused as ParseCallers refuses it.
+// configured holds the config value `callers`: asked of the runtime once, by a watch, and replaced on each change of
+// the value, so a call never asks (issue 1966: an ask that timed out refused every verb).
+var configured = stdio.HoldVerbCallers(CallersConfig, VerbsOf(ImageSeat), DefaultCallers())
+
+// ConfiguredCallers is the config value `callers` as mesh-config resolved it for this machine, held from the tools
+// runtime's watch of it (never an environment variable: nothing renders a config value into a program's environment);
+// unset is DefaultCallers, and Self on release's list is refused as ParseCallers refuses it.
 func ConfiguredCallers() (Callers, error) {
-	c, err := stdio.ConfiguredVerbCallers(CallersConfig, VerbsOf(ImageSeat), DefaultCallers())
+	c, err := configured()
 	if err != nil {
 		return nil, err
 	}

modules/gitea/internal/packageseats/holder.go

@@ -77,10 +77,12 @@ func DefaultCallers() Callers {
 		VerbVersions: {stdio.AnyCaller}}
 }
 
-// ConfiguredCallers is the config value `callers` as mesh-config resolved it; unset is DefaultCallers.
-func ConfiguredCallers() (Callers, error) {
-	return stdio.ConfiguredVerbCallers("callers", Verbs, DefaultCallers())
-}
+// configured holds the config value `callers`: asked of the runtime once, by a watch, and replaced on each change of
+// the value, so a call never asks (issue 1966).
+var configured = stdio.HoldVerbCallers("callers", Verbs, DefaultCallers())
+
+// ConfiguredCallers is the config value `callers` as mesh-config resolved it, held from its watch; unset is DefaultCallers.
+func ConfiguredCallers() (Callers, error) { return configured() }
 
 // Publish is a publish as the seats' contract names it (mesh-contracts npmpackageregistry and gopackageregistry share
 // one shape): what the tools bundle reads from either seat's PublishInput.