Remove hardcoded magic string in keyshare username auto-issuance

irmaclient/handlers.go

@@ -19,8 +19,13 @@ var _ Handler = (*keyshareEnrollmentHandler)(nil)
 // Session handlers in the order they are called
 
 func (h *keyshareEnrollmentHandler) RequestIssuancePermission(request irma.IssuanceRequest, ServerName string, callback PermissionHandler) {
-	h.kss.Username = request.Credentials[0].Attributes["email"] // TODO magic string
+	// Fetch the username from the credential request and save it along with the scheme manager
+	smi := request.Credentials[0].CredentialTypeID.IssuerIdentifier().SchemeManagerIdentifier()
+	attr := irma.NewAttributeTypeIdentifier(h.client.Configuration.SchemeManagers[smi].KeyshareAttribute)
+	h.kss.Username = request.Credentials[0].Attributes[attr.Name()]
 	h.client.storage.StoreKeyshareServers(h.client.keyshareServers)
+
+	// Do the issuance
 	callback(true, nil)
 }