Initial DDC release

internal/jobs/workflows.go

@@ -0,0 +1,102 @@
+package jobs
+
+import (
+	"errors"
+	"os"
+	"path/filepath"
+
+	"ddc/internal/diskspace"
+	"ddc/internal/extract"
+	"ddc/internal/files"
+)
+
+const maxArchiveEntries = 100000
+
+var errNotArchive = errors.New("selected file is not a supported archive")
+
+func (manager *Manager) download(job *Job) {
+	defer job.workers.Done()
+
+	if !manager.slots.acquire(job.jobContext, manager.concurrencyLimit) {
+		return
+	}
+	defer manager.slots.release()
+
+	job.setStatus(StatusDownloading, "")
+	filePath, err := manager.downloader.Download(job.jobContext, job.sourceURL, job.directory, manager.reservedBytes(), job)
+	if err != nil {
+		manager.finishWithError(job, StatusFailed, "", err)
+		return
+	}
+	job.SetFileName(filepath.Base(filePath))
+
+	if job.autoExtract && extract.IsArchive(filePath) {
+		job.setStatus(StatusExtracting, "")
+		destination, err := manager.extractArchive(job, filePath)
+		if err != nil {
+			manager.finishWithError(job, StatusReady, "Extraction failed: ", err)
+			return
+		}
+		job.SetFileName(filepath.Base(destination))
+	}
+
+	job.setStatus(StatusReady, "")
+}
+
+func (manager *Manager) Extract(id, relativePath string) error {
+	job, err := manager.lookup(id)
+	if err != nil {
+		return err
+	}
+
+	archivePath, err := files.ResolveInside(job.directory, relativePath)
+	if err != nil {
+		return invalid(err)
+	}
+	info, err := os.Stat(archivePath)
+	if err != nil || !info.Mode().IsRegular() || !extract.IsArchive(archivePath) {
+		return invalid(errNotArchive)
+	}
+
+	if !job.begin(StatusReady, StatusExtracting) {
+		return ErrJobBusy
+	}
+	go func() {
+		defer job.workers.Done()
+		if _, err := manager.extractArchive(job, archivePath); err != nil {
+			manager.finishWithError(job, StatusReady, "Extraction failed: ", err)
+			return
+		}
+		job.setStatus(StatusReady, "")
+	}()
+	return nil
+}
+
+func (manager *Manager) extractArchive(job *Job, archivePath string) (string, error) {
+	available, err := diskspace.Available(job.directory)
+	if err != nil {
+		return "", err
+	}
+	limit := available - manager.reservedBytes()
+	if limit <= 0 {
+		return "", diskspace.ErrInsufficientSpace
+	}
+
+	directoryName := extract.DirectoryName(filepath.Base(archivePath))
+	destination := files.UniquePath(filepath.Join(filepath.Dir(archivePath), directoryName))
+	limits := extract.Limits{MaxBytes: limit, MaxEntries: maxArchiveEntries}
+
+	job.resetProgress()
+	if err := extract.Archive(job.jobContext, archivePath, destination, limits, job); err != nil {
+		return "", err
+	}
+	return destination, os.Remove(archivePath)
+}
+
+func (manager *Manager) finishWithError(job *Job, status Status, prefix string, err error) {
+	if job.jobContext.Err() != nil {
+		job.setStatus(StatusCancelled, "")
+		return
+	}
+	job.setStatus(status, prefix+err.Error())
+}