27 lines
742 B
Go
27 lines
742 B
Go
package guardiand
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import (
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"fmt"
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"net"
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"github.com/coreos/go-systemd/activation"
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)
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func getSDListeners() ([]net.Listener, error) {
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// We use systemd socket activation for (almost) zero downtime deployment -
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// systemd will keep the socket open even while we restart the process
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// (plus, it allows us to bind to unprivileged ports without extra capabilities).
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//
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// Read more: https://vincent.bernat.ch/en/blog/2018-systemd-golang-socket-activation
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listeners, err := activation.Listeners()
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if err != nil {
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return nil, fmt.Errorf("cannot retrieve listeners: %v", err)
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}
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if len(listeners) != 1 {
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return nil, fmt.Errorf("unexpected number of sockets passed by systemd (%d != 1)", len(listeners))
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}
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return listeners, nil
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}
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