57 lines
1.2 KiB
Go
57 lines
1.2 KiB
Go
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// Package don is a little helper if you need to check for the readiness of something.
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// This could be a command to run (like ssh) or a `db.Ping()` for check of the readiness
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// of a database container.
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package don
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import (
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"errors"
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"os/exec"
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"time"
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"github.com/rs/zerolog/log"
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)
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var errTimeout = errors.New("timeout")
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// Cmd returns a `func() bool` for working with don.Check. It executes a command and
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// returns a true if everything looks fine or a false if there was some kind of error.
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func Cmd(c string) func() bool {
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return func() bool {
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cmd := exec.Command("sh", "-c", c)
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if err := cmd.Run(); err != nil {
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log.Warn().Err(err).Msg("cmd has error")
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return false
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}
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return true
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}
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}
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// Check takes a function that executes something and returns a bool to indicate if
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// something is ready or not. It returns an error if it timeouts.
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func Check(f func() bool, timeout time.Duration, retry time.Duration) error {
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chReady := make(chan struct{})
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go func() {
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for {
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if f() {
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chReady <- struct{}{}
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return
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}
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<-time.After(retry)
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log.Info().Msg("retrying")
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}
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}()
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select {
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case <-chReady:
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return nil
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case <-time.After(timeout):
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return errTimeout
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}
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}
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