Finished dummy download API.

webapi/Download Temp.go

@@ -0,0 +1,129 @@
+/*
+File Name:  Download Temp.go
+Copyright:  2021 Peernet Foundation s.r.o.
+Author:     Peter Kleissner
+
+Temporary download code to provide dummy results for testing. To be replaced!
+*/
+
+package webapi
+
+import (
+	"math/rand"
+	"os"
+	"time"
+)
+
+// Start is a dummy downloader
+func (info *downloadInfo) Start() {
+	time.Sleep(time.Second * time.Duration(rand.Intn(5)))
+
+	// request metadata
+	info.file = createTestResult(-1)
+	info.fileU = blockRecordFileToAPI(info.file)
+
+	// join swarm
+
+	info.status = DownloadActive
+
+	// start download
+	for n := uint64(0); n < 10; n++ {
+		time.Sleep(time.Second * time.Duration(rand.Intn(5)))
+
+		randomData := make([]byte, info.file.Size/10)
+		rand.Read(randomData)
+
+		info.storeDownloadData(randomData, n*info.file.Size/10)
+	}
+
+	info.Finish()
+	info.DeleteDefer(time.Hour * 1) // cache the details for 1 hour before removing
+}
+
+// Pause pauses the download. Status is DownloadResponseX.
+func (info *downloadInfo) Pause() (status int) {
+	info.Lock()
+	defer info.Unlock()
+
+	if info.status != DownloadActive { // The download must be active to be paused.
+		return DownloadResponseActionInvalid
+	}
+
+	info.status = DownloadPause
+
+	return DownloadResponseSuccess
+}
+
+// Resume resumes the download. Status is DownloadResponseX.
+func (info *downloadInfo) Resume() (status int) {
+	info.Lock()
+	defer info.Unlock()
+
+	if info.status != DownloadPause { // The download must be paused to resume.
+		return DownloadResponseActionInvalid
+	}
+
+	info.status = DownloadActive
+
+	return DownloadResponseSuccess
+}
+
+// Cancel cancels the download. Status is DownloadResponseX.
+func (info *downloadInfo) Cancel() (status int) {
+	info.Lock()
+	defer info.Unlock()
+
+	if info.status >= DownloadCanceled { // The download must not be already canceled or finished.
+		return DownloadResponseActionInvalid
+	}
+
+	info.status = DownloadCanceled
+	info.DiskFile.Handle.Close()
+
+	return DownloadResponseSuccess
+}
+
+// Finish marks the download as finished.
+func (info *downloadInfo) Finish() (status int) {
+	info.Lock()
+	defer info.Unlock()
+
+	if info.status != DownloadActive { // The download must be active.
+		return DownloadResponseActionInvalid
+	}
+
+	info.status = DownloadFinished
+	info.DiskFile.Handle.Close()
+
+	return DownloadResponseSuccess
+}
+
+// initDiskFile creates the target file
+func (info *downloadInfo) initDiskFile(path string) (err error) {
+	info.DiskFile.Name = path
+	info.DiskFile.Handle, err = os.OpenFile(path, os.O_RDWR|os.O_CREATE, 0666)
+
+	return err
+}
+
+// storeDownloadData stores downloaded data. It does not change the download status.
+func (info *downloadInfo) storeDownloadData(data []byte, offset uint64) (status int) {
+	info.Lock()
+	defer info.Unlock()
+
+	if info.status != DownloadActive { // The download must be active.
+		return DownloadResponseActionInvalid
+	}
+
+	//if _, err := info.DiskFile.Handle.Seek(int64(offset), 0); err != nil {
+	//	return err
+	//}
+
+	if _, err := info.DiskFile.Handle.WriteAt(data, int64(offset)); err != nil {
+		return DownloadResponseFileWrite
+	}
+
+	info.DiskFile.StoredSize += uint64(len(data))
+
+	return DownloadResponseSuccess
+}