packer-cn/common/multistep_runner.go

157 lines
3.5 KiB
Go

package common
import (
"fmt"
"log"
"os"
"reflect"
"strings"
"time"
"github.com/mitchellh/multistep"
"github.com/mitchellh/packer/packer"
)
func newRunner(steps []multistep.Step, config PackerConfig, ui packer.Ui) (multistep.Runner, multistep.DebugPauseFn) {
switch config.PackerOnError {
case "cleanup":
case "abort":
for i, step := range steps {
steps[i] = abortStep{step, ui}
}
case "ask":
for i, step := range steps {
steps[i] = askStep{step, ui}
}
default:
ui.Error(fmt.Sprintf("Ignoring -on-error=%q argument: unknown on-error value", config.PackerOnError))
}
if config.PackerDebug {
pauseFn := MultistepDebugFn(ui)
return &multistep.DebugRunner{Steps: steps, PauseFn: pauseFn}, pauseFn
} else {
return &multistep.BasicRunner{Steps: steps}, nil
}
}
// NewRunner returns a multistep.Runner that runs steps augmented with support
// for -debug and -on-error command line arguments.
func NewRunner(steps []multistep.Step, config PackerConfig, ui packer.Ui) multistep.Runner {
runner, _ := newRunner(steps, config, ui)
return runner
}
// NewRunnerWithPauseFn returns a multistep.Runner that runs steps augmented
// with support for -debug and -on-error command line arguments. With -debug it
// puts the multistep.DebugPauseFn that will pause execution between steps into
// the state under the key "pauseFn".
func NewRunnerWithPauseFn(steps []multistep.Step, config PackerConfig, ui packer.Ui, state multistep.StateBag) multistep.Runner {
runner, pauseFn := newRunner(steps, config, ui)
if pauseFn != nil {
state.Put("pauseFn", pauseFn)
}
return runner
}
func typeName(i interface{}) string {
return reflect.Indirect(reflect.ValueOf(i)).Type().Name()
}
type abortStep struct {
step multistep.Step
ui packer.Ui
}
func (s abortStep) Run(state multistep.StateBag) multistep.StepAction {
return s.step.Run(state)
}
func (s abortStep) Cleanup(state multistep.StateBag) {
if _, ok := state.GetOk(multistep.StateCancelled); ok {
s.ui.Error("Interrupted, aborting...")
os.Exit(1)
}
if _, ok := state.GetOk(multistep.StateHalted); ok {
s.ui.Error(fmt.Sprintf("Step %q failed, aborting...", typeName(s.step)))
os.Exit(1)
}
s.step.Cleanup(state)
}
type askStep struct {
step multistep.Step
ui packer.Ui
}
func (s askStep) Run(state multistep.StateBag) (action multistep.StepAction) {
for {
action = s.step.Run(state)
if action != multistep.ActionHalt {
return
}
switch ask(s.ui, typeName(s.step), state) {
case askCleanup:
return
case askAbort:
os.Exit(1)
case askRetry:
continue
}
}
}
func (s askStep) Cleanup(state multistep.StateBag) {
s.step.Cleanup(state)
}
type askResponse int
const (
askCleanup askResponse = iota
askAbort
askRetry
)
func ask(ui packer.Ui, name string, state multistep.StateBag) askResponse {
ui.Say(fmt.Sprintf("Step %q failed", name))
result := make(chan askResponse)
go func() {
result <- askPrompt(ui)
}()
for {
select {
case response := <-result:
return response
case <-time.After(100 * time.Millisecond):
if _, ok := state.GetOk(multistep.StateCancelled); ok {
return askCleanup
}
}
}
}
func askPrompt(ui packer.Ui) askResponse {
for {
line, err := ui.Ask("[C]lean up and exit, [a]bort without cleanup, or [r]etry step (build may fail even if retry succeeds)?")
if err != nil {
log.Printf("Error asking for input: %s", err)
}
input := strings.ToLower(line) + "c"
switch input[0] {
case 'c':
return askCleanup
case 'a':
return askAbort
case 'r':
return askRetry
}
ui.Say(fmt.Sprintf("Incorrect input: %#v", line))
}
}