7190fbeed8
- Startup scripts can be provided through the instance creation metadata field 'startup-script'. - Script log can be copied to a GCS location by setting the metadata field 'startup-script-log-dest'. Added Retry method to googlecompute package. Added GetSerialPortOutput to googlecompute Drivers. Added StepWaitInstanceStartup (and associated test) which waits for an instance startup-script to finish. Changed the instance service account to use the same service account as the one provided in the Packer config template. It was the project default service account. Tested googlecompute package with 'go test' and also performed builds with a startup script and without a startup script.
45 lines
1.3 KiB
Go
45 lines
1.3 KiB
Go
package googlecompute
|
|
|
|
import (
|
|
"fmt"
|
|
"math"
|
|
"time"
|
|
)
|
|
|
|
var RetryExhaustedError error = fmt.Errorf("Function never succeeded in Retry")
|
|
|
|
// Retry retries a function up to numTries times with exponential backoff.
|
|
// If numTries == 0, retry indefinitely. If interval == 0, Retry will not delay retrying and there will be
|
|
// no exponential backoff. If maxInterval == 0, maxInterval is set to +Infinity.
|
|
// Intervals are in seconds.
|
|
// Returns an error if initial > max intervals, if retries are exhausted, or if the passed function returns
|
|
// an error.
|
|
func Retry(initialInterval float64, maxInterval float64, numTries uint, function func() (bool, error)) error {
|
|
if maxInterval == 0 {
|
|
maxInterval = math.Inf(1)
|
|
} else if initialInterval < 0 || initialInterval > maxInterval {
|
|
return fmt.Errorf("Invalid retry intervals (negative or initial < max). Initial: %f, Max: %f.", initialInterval, maxInterval)
|
|
}
|
|
|
|
var err error
|
|
done := false
|
|
interval := initialInterval
|
|
for i := uint(0); !done && (numTries == 0 || i < numTries); i++ {
|
|
done, err = function()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if !done {
|
|
// Retry after delay. Calculate next delay.
|
|
time.Sleep(time.Duration(interval) * time.Second)
|
|
interval = math.Min(interval * 2, maxInterval)
|
|
}
|
|
}
|
|
|
|
if !done {
|
|
return RetryExhaustedError
|
|
}
|
|
return nil
|
|
}
|