feat: allow system config changes (#3876)

* feat: run repeatable setup steps

* feat: react to system config changes

* renaming

cmd/setup/config_change.go

@@ -0,0 +1,60 @@
+package setup
+
+import (
+	"context"
+
+	"github.com/zitadel/zitadel/internal/command"
+	"github.com/zitadel/zitadel/internal/config/systemdefaults"
+	"github.com/zitadel/zitadel/internal/eventstore"
+)
+
+type externalConfigChange struct {
+	es             *eventstore.Eventstore
+	ExternalDomain string `json:"externalDomain"`
+	ExternalSecure bool   `json:"externalSecure"`
+	ExternalPort   uint16 `json:"externalPort"`
+
+	currentExternalDomain string
+	currentExternalSecure bool
+	currentExternalPort   uint16
+}
+
+func (mig *externalConfigChange) SetLastExecution(lastRun map[string]interface{}) {
+	mig.currentExternalDomain, _ = lastRun["externalDomain"].(string)
+	externalPort, _ := lastRun["externalPort"].(float64)
+	mig.currentExternalPort = uint16(externalPort)
+	mig.currentExternalSecure, _ = lastRun["externalSecure"].(bool)
+}
+
+func (mig *externalConfigChange) Check() bool {
+	return mig.currentExternalSecure != mig.ExternalSecure ||
+		mig.currentExternalPort != mig.ExternalPort ||
+		mig.currentExternalDomain != mig.ExternalDomain
+}
+
+func (mig *externalConfigChange) Execute(ctx context.Context) error {
+	cmd, err := command.StartCommands(mig.es,
+		systemdefaults.SystemDefaults{},
+		nil,
+		nil,
+		nil,
+		mig.ExternalDomain,
+		mig.ExternalSecure,
+		mig.ExternalPort,
+		nil,
+		nil,
+		nil,
+		nil,
+		nil,
+		nil,
+		nil)
+
+	if err != nil {
+		return err
+	}
+	return cmd.ChangeSystemConfig(ctx, mig.currentExternalDomain, mig.currentExternalPort, mig.currentExternalSecure)
+}
+
+func (mig *externalConfigChange) String() string {
+	return "config_change"
+}