FindConfigMapNameFromTCAnno is used to find ConfigMap name from tc.annotations which is saved before deleting STS.

FindConfigMapVolume returns the configmap which's name matches the predicate in a PodSpec, empty indicates not found.

SetStatefulSetLastAppliedConfigAnnotation set last applied config to Statefulset's annotation.

SetUpgradePartition set statefulSet's rolling update partition.

StatefulSetIsUpgrading confirms whether the statefulSet is upgrading phase.

UpdateConfigMapIfNeed set the toml field as the old one if they are logically equal.

UpdateStatefulSet is a template function to update the statefulset of components.

LastAppliedConfigAnnotation is annotation key of last applied configuration.