common: Add new StepDownload to DRY up downloads

This commit is contained in:
Mitchell Hashimoto 2013-08-15 14:05:36 -04:00
parent 245b569c9b
commit bb352e5011
4 changed files with 147 additions and 91 deletions

View File

@ -295,7 +295,13 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
steps := []multistep.Step{
new(stepDownloadGuestAdditions),
new(stepDownloadISO),
&common.StepDownload{
Checksum: b.config.ISOChecksum,
ChecksumType: b.config.ISOChecksumType,
Description: "ISO",
ResultKey: "iso_path",
Url: []string{b.config.ISOUrl},
},
new(stepPrepareOutputDir),
&common.StepCreateFloppy{
Files: b.config.FloppyFiles,

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@ -1,90 +0,0 @@
package virtualbox
import (
"encoding/hex"
"fmt"
"github.com/mitchellh/multistep"
"github.com/mitchellh/packer/common"
"github.com/mitchellh/packer/packer"
"log"
"time"
)
// This step downloads the ISO specified.
//
// Uses:
// cache packer.Cache
// config *config
// ui packer.Ui
//
// Produces:
// iso_path string
type stepDownloadISO struct{}
func (s stepDownloadISO) Run(state map[string]interface{}) multistep.StepAction {
cache := state["cache"].(packer.Cache)
config := state["config"].(*config)
ui := state["ui"].(packer.Ui)
checksum, err := hex.DecodeString(config.ISOChecksum)
if err != nil {
state["error"] = fmt.Errorf("Error parsing checksum: %s", err)
return multistep.ActionHalt
}
log.Printf("Acquiring lock to download the ISO.")
cachePath := cache.Lock(config.ISOUrl)
defer cache.Unlock(config.ISOUrl)
downloadConfig := &common.DownloadConfig{
Url: config.ISOUrl,
TargetPath: cachePath,
CopyFile: false,
Hash: common.HashForType(config.ISOChecksumType),
Checksum: checksum,
}
download := common.NewDownloadClient(downloadConfig)
downloadCompleteCh := make(chan error, 1)
go func() {
ui.Say("Copying or downloading ISO. Progress will be reported periodically.")
cachePath, err = download.Get()
downloadCompleteCh <- err
}()
progressTicker := time.NewTicker(5 * time.Second)
defer progressTicker.Stop()
DownloadWaitLoop:
for {
select {
case err := <-downloadCompleteCh:
if err != nil {
err := fmt.Errorf("Error downloading ISO: %s", err)
state["error"] = err
ui.Error(err.Error())
return multistep.ActionHalt
}
break DownloadWaitLoop
case <-progressTicker.C:
progress := download.PercentProgress()
if progress >= 0 {
ui.Message(fmt.Sprintf("Download progress: %d%%", progress))
}
case <-time.After(1 * time.Second):
if _, ok := state[multistep.StateCancelled]; ok {
ui.Say("Interrupt received. Cancelling download...")
return multistep.ActionHalt
}
}
}
log.Printf("Path to ISO on disk: %s", cachePath)
state["iso_path"] = cachePath
return multistep.ActionContinue
}
func (stepDownloadISO) Cleanup(map[string]interface{}) {}

126
common/step_download.go Normal file
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@ -0,0 +1,126 @@
package common
import (
"encoding/hex"
"fmt"
"github.com/mitchellh/multistep"
"github.com/mitchellh/packer/packer"
"log"
"time"
)
// StepDownload downloads a remote file using the download client within
// this package. This step handles setting up the download configuration,
// progress reporting, interrupt handling, etc.
//
// Uses:
// cache packer.Cache
// ui packer.Ui
type StepDownload struct {
// The checksum and the type of the checksum for the download
Checksum string
ChecksumType string
// A short description of the type of download being done. Example:
// "ISO" or "Guest Additions"
Description string
// The name of the key where the final path of the ISO will be put
// into the state.
ResultKey string
// A list of URLs to attempt to download this thing.
Url []string
}
func (s *StepDownload) Run(state map[string]interface{}) multistep.StepAction {
cache := state["cache"].(packer.Cache)
ui := state["ui"].(packer.Ui)
checksum, err := hex.DecodeString(s.Checksum)
if err != nil {
state["error"] = fmt.Errorf("Error parsing checksum: %s", err)
return multistep.ActionHalt
}
ui.Say(fmt.Sprintf("Downloading or copying %s", s.Description))
var finalPath string
for _, url := range s.Url {
ui.Message(fmt.Sprintf("Downloading or copying: %s", url))
log.Printf("Acquiring lock to download: %s", url)
cachePath := cache.Lock(url)
defer cache.Unlock(url)
config := &DownloadConfig{
Url: url,
TargetPath: cachePath,
CopyFile: false,
Hash: HashForType(s.ChecksumType),
Checksum: checksum,
}
path, err, retry := s.download(config, state)
if err != nil {
ui.Message(fmt.Sprintf("Error downloading: %s", err))
}
if !retry {
return multistep.ActionHalt
}
if err == nil {
finalPath = path
break
}
}
if finalPath == "" {
err := fmt.Errorf("%s download failed.", s.Description)
state["error"] = err
ui.Error(err.Error())
return multistep.ActionHalt
}
state[s.ResultKey] = finalPath
return multistep.ActionContinue
}
func (s *StepDownload) Cleanup(map[string]interface{}) {}
func (s *StepDownload) download(config *DownloadConfig, state map[string]interface{}) (string, error, bool) {
var path string
ui := state["ui"].(packer.Ui)
download := NewDownloadClient(config)
downloadCompleteCh := make(chan error, 1)
go func() {
var err error
path, err = download.Get()
downloadCompleteCh <- err
}()
progressTicker := time.NewTicker(5 * time.Second)
defer progressTicker.Stop()
for {
select {
case err := <-downloadCompleteCh:
if err != nil {
return "", err, true
}
return path, nil, true
case <-progressTicker.C:
progress := download.PercentProgress()
if progress >= 0 {
ui.Message(fmt.Sprintf("Download progress: %d%%", progress))
}
case <-time.After(1 * time.Second):
if _, ok := state[multistep.StateCancelled]; ok {
ui.Say("Interrupt received. Cancelling download...")
return "", nil, false
}
}
}
}

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@ -0,0 +1,14 @@
package common
import (
"github.com/mitchellh/multistep"
"testing"
)
func TestStepDownload_Impl(t *testing.T) {
var raw interface{}
raw = new(StepDownload)
if _, ok := raw.(multistep.Step); !ok {
t.Fatalf("download should be a step")
}
}