util

func DetectPublicNetworkParams ¶

func DetectPublicNetworkParams(publicIPs *[]net.IP, internalIPs []net.IP, netDev *string) error

DetectPublicNetworkParams tries to be smart and find a public IP address and network interface for the local host.

If *publicIPs is nil, attempts to resolve the local hostname and look for non-local addresses. If none are found, figures out the IP from the network interface, if given, or finds the first non-loopback interface.

If *netDev is an empty string, tries to figure out the network device to use from either internalIPs or *publicIPs, whichever is not nil. The netDev pointer itself can be nil, in which case no network device detection is attempted.

func IPFlag ¶

func IPFlag(name, help string) *net.IP

func IPListFlag ¶

func IPListFlag(name, help string) *[]net.IP

func RunCron ¶

func RunCron(ctx context.Context, d time.Duration, fn func(context.Context))

RunCron invokes fn periodically, until the context is canceled. It is a simple wrapper for time.Ticker, but fn is also called immediately as soon as the timer starts.

func WriteFileIfChanged ¶

func WriteFileIfChanged(path string, data []byte) (bool, error)

WriteFileIfChanged updates the contents of a file if they have changed. It returns false if the file already exists and its contents are equal to 'data', true in any other case.