Support canceling an in-progress download

This commit is contained in:
Dane Everitt 2020-12-20 12:53:40 -08:00
parent c718da20e3
commit c8d297a056
No known key found for this signature in database
GPG Key ID: EEA66103B3D71F53
5 changed files with 91 additions and 11 deletions

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@ -5,6 +5,7 @@ import (
"emperror.dev/errors"
"github.com/google/uuid"
"github.com/pterodactyl/wings/server"
"io"
"net/http"
"net/url"
"path/filepath"
@ -13,6 +14,18 @@ import (
"time"
)
type Counter struct {
total int
onWrite func(total int)
}
func (c *Counter) Write(p []byte) (int, error) {
n := len(p)
c.total += n
c.onWrite(c.total)
return n, nil
}
type Downloader struct {
mu sync.RWMutex
downloadCache map[string]Download
@ -28,6 +41,7 @@ type Download struct {
Identifier string
req DownloadRequest
server *server.Server
progress float64
cancelFunc *context.CancelFunc
}
@ -53,6 +67,28 @@ func New(s *server.Server, r DownloadRequest) *Download {
return &dl
}
// Returns all of the tracked downloads for a given server instance.
func ByServer(sid string) []Download {
var downloads []Download
if v, ok := instance.serverCache[sid]; ok {
for _, id := range v {
if dl, dlok := instance.downloadCache[id]; dlok {
downloads = append(downloads, dl)
}
}
}
return downloads
}
// Returns a single Download matching a given identifier. If no download is found
// the second argument in the response will be false.
func ByID(dlid string) (Download, bool) {
if v, ok := instance.downloadCache[dlid]; ok {
return v, true
}
return Download{}, false
}
// Executes a given download for the server and begins writing the file to the disk. Once
// completed the download will be removed from the cache.
func (dl *Download) Execute() error {
@ -82,7 +118,9 @@ func (dl *Download) Execute() error {
fnameparts := strings.Split(dl.req.URL.Path, "/")
p := filepath.Join(dl.req.Directory, fnameparts[len(fnameparts)-1])
dl.server.Log().WithField("path", p).Debug("writing remote file to disk")
if err := dl.server.Filesystem().Writefile(p, res.Body); err != nil {
r := io.TeeReader(res.Body, dl.counter(res.ContentLength))
if err := dl.server.Filesystem().Writefile(p, r); err != nil {
return errors.WrapIf(err, "downloader: failed to write file to server directory")
}
return nil
@ -97,6 +135,23 @@ func (dl *Download) Cancel() {
instance.remove(dl.Identifier)
}
// Checks if the given download belongs to the provided server.
func (dl *Download) BelongsTo(s *server.Server) bool {
return dl.server.Id() == s.Id()
}
// Handles a write event by updating the progress completed percentage and firing off
// events to the server websocket as needed.
func (dl *Download) counter(contentLength int64) *Counter {
onWrite := func(t int) {
dl.progress = float64(t) / float64(contentLength)
}
return &Counter{
onWrite: onWrite,
}
}
// Tracks a download in the internal cache for this instance.
func (d *Downloader) track(dl Download) {
d.mu.Lock()

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@ -121,16 +121,20 @@ func (e *RequestError) Abort(c *gin.Context) {
// Looks at the given RequestError and determines if it is a specific filesystem error that
// we can process and return differently for the user.
func (e *RequestError) getAsFilesystemError() (int, string) {
if errors.Is(e.err, os.ErrNotExist) || filesystem.IsErrorCode(e.err, filesystem.ErrCodePathResolution) {
err := errors.Unwrap(e.err)
if err == nil {
return 0, ""
}
if errors.Is(err, os.ErrNotExist) || filesystem.IsErrorCode(err, filesystem.ErrCodePathResolution) {
return http.StatusNotFound, "The requested resource was not found on the system."
}
if filesystem.IsErrorCode(e.err, filesystem.ErrCodeDiskSpace) {
if filesystem.IsErrorCode(err, filesystem.ErrCodeDiskSpace) {
return http.StatusConflict, "There is not enough disk space available to perform that action."
}
if strings.HasSuffix(e.err.Error(), "file name too long") {
if strings.HasSuffix(err.Error(), "file name too long") {
return http.StatusBadRequest, "Cannot perform that action: file name is too long."
}
if e, ok := e.err.(*os.SyscallError); ok && e.Syscall == "readdirent" {
if e, ok := err.(*os.SyscallError); ok && e.Syscall == "readdirent" {
return http.StatusNotFound, "The requested directory does not exist."
}
return 0, ""

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@ -83,6 +83,7 @@ func Configure() *gin.Engine {
files.POST("/copy", postServerCopyFile)
files.POST("/write", postServerWriteFile)
files.POST("/pull", postServerPullRemoteFile)
files.DELETE("/pull/:download", deleteServerPullRemoteFile)
files.POST("/create-directory", postServerCreateDirectory)
files.POST("/delete", postServerDeleteFiles)
files.POST("/compress", postServerCompressFiles)

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@ -6,6 +6,7 @@ import (
"emperror.dev/errors"
"github.com/apex/log"
"github.com/gin-gonic/gin"
"github.com/pterodactyl/wings/router/downloader"
"github.com/pterodactyl/wings/router/tokens"
"github.com/pterodactyl/wings/server"
"net/http"
@ -210,6 +211,11 @@ func deleteServer(c *gin.Context) {
s.Throttler().StopTimer()
s.Websockets().CancelAll()
// Remove any pending remote file downloads for the server.
for _, dl := range downloader.ByServer(s.Id()) {
dl.Cancel()
}
// Destroy the environment; in Docker this will handle a running container and
// forcibly terminate it before removing the container, so we do not need to handle
// that here.

View File

@ -266,13 +266,27 @@ func postServerPullRemoteFile(c *gin.Context) {
Directory: data.Directory,
})
// Execute this pull in a seperate thread since it may take a long time to complete.
go func() {
s.Log().WithField("download_id", dl.Identifier).WithField("url", u.String()).Info("starting pull of remote file to disk")
if err := dl.Execute(); err != nil {
WithError(c, err)
return
}
s.Log().WithField("download_id", dl.Identifier).WithField("error", err).Error("failed to pull remote file")
} else {
s.Log().WithField("download_id", dl.Identifier).Info("completed pull of remote file")
}
}()
c.JSON(http.StatusAccepted, gin.H{
"identifier": dl.Identifier,
})
}
// Stops a remote file download if it exists and belongs to this server.
func deleteServerPullRemoteFile(c *gin.Context) {
s := ExtractServer(c)
if dl, ok := downloader.ByID(c.Param("download")); ok && dl.BelongsTo(s) {
dl.Cancel()
}
c.Status(http.StatusNoContent)
}