kubernetes/cmd/kubeadm/app/phases/upgrade/compute.go

type Upgrade …

// CanUpgradeKubelets returns whether an upgrade of any kubelet in the cluster is possible
func (u *Upgrade) CanUpgradeKubelets() bool { … }

type ClusterState …

// GetAvailableUpgrades fetches all versions from the specified VersionGetter and computes which
// kinds of upgrades can be performed
func GetAvailableUpgrades(versionGetterImpl VersionGetter, experimentalUpgradesAllowed, rcUpgradesAllowed bool, client clientset.Interface, printer output.Printer) ([]Upgrade, error) { … }

func getBranchFromVersion(version string) string { … }

func patchVersionBranchExists(clusterVersion, stableVersion *versionutil.Version) bool { … }

func patchUpgradePossible(clusterVersion, patchVersion *versionutil.Version) bool { … }

func rcUpgradePossible(clusterVersion, previousBranchLatestVersion *versionutil.Version) bool { … }

func minorUpgradePossibleWithPatchRelease(stableVersion, patchVersion *versionutil.Version) bool { … }

func getSuggestedEtcdVersion(isExternalEtcd bool, kubernetesVersion string) string { … }

func getLatestClusterVersion(kubeAPIServerVersions map[string][]string) (*versionutil.Version, error) { … }