Implement download revision

3 files changed, 111 insertions, 0 deletions

diff --git a/drive/revision_download.go b/drive/revision_download.go
new file mode 100644
index 0000000..c26c3ce
--- /dev/null
+++ b/drive/revision_download.go
@@ -0,0 +1,70 @@
+package drive
+
+import (
+    "fmt"
+    "io"
+    "os"
+)
+
+type DownloadRevisionArgs struct {
+    Out io.Writer
+    FileId string
+    RevisionId string
+    Force bool
+    NoProgress bool
+    Stdout bool
+}
+
+func (self *Drive) DownloadRevision(args DownloadRevisionArgs) (err error) {
+    getRev := self.service.Revisions.Get(args.FileId, args.RevisionId)
+
+    rev, err := getRev.Fields("originalFilename").Do()
+    if err != nil {
+        return fmt.Errorf("Failed to get file: %s", err)
+    }
+
+    if rev.OriginalFilename == "" {
+        return fmt.Errorf("Download is not supported for this file type")
+    }
+
+    res, err := getRev.Download()
+    if err != nil {
+        return fmt.Errorf("Failed to download file: %s", err)
+    }
+
+    // Close body on function exit
+    defer res.Body.Close()
+
+    if args.Stdout {
+        // Write file content to stdout
+        _, err := io.Copy(os.Stdout, res.Body)
+        return err
+    }
+
+    // Check if file exists
+    if !args.Force && fileExists(rev.OriginalFilename) {
+        return fmt.Errorf("File '%s' already exists, use --force to overwrite", rev.OriginalFilename)
+    }
+
+    // Create new file
+    outFile, err := os.Create(rev.OriginalFilename)
+    if err != nil {
+        return fmt.Errorf("Unable to create new file: %s", err)
+    }
+
+    // Close file on function exit
+    defer outFile.Close()
+
+    // Save file to disk
+    bytes, err := io.Copy(outFile, res.Body)
+    if err != nil {
+        return fmt.Errorf("Failed saving file: %s", err)
+    }
+
+    fmt.Fprintf(args.Out, "Downloaded '%s' at %s, total %d\n", rev.OriginalFilename, "x/s", bytes)
+
+    //if deleteSourceFile {
+    //    self.Delete(args.Id)
+    //}
+    return
+}
diff --git a/gdrive.go b/gdrive.go
index f20f9f3..967f6ec 100644
--- a/gdrive.go
+++ b/gdrive.go
@@ -125,6 +125,34 @@ func main() {
             },
         },
         &cli.Handler{
+            Pattern: "[global options] download revision [options] <fileId> <revisionId>",
+            Description: "Download revision",
+            Callback: downloadRevisionHandler,
+            Flags: cli.Flags{
+                "global options": globalFlags,
+                "options": []cli.Flag{
+                    cli.BoolFlag{
+                        Name: "force",
+                        Patterns: []string{"-f", "--force"},
+                        Description: "Overwrite existing file",
+                        OmitValue: true,
+                    },
+                    cli.BoolFlag{
+                        Name: "noProgress",
+                        Patterns: []string{"--no-progress"},
+                        Description: "Hide progress",
+                        OmitValue: true,
+                    },
+                    cli.BoolFlag{
+                        Name: "stdout",
+                        Patterns: []string{"--stdout"},
+                        Description: "Write file content to stdout",
+                        OmitValue: true,
+                    },
+                },
+            },
+        },
+        &cli.Handler{
             Pattern: "[global options] upload [options] <path>",
             Description: "Upload file or directory",
             Callback: uploadHandler,
diff --git a/handlers_drive.go b/handlers_drive.go
index f208bed..1b01996 100644
--- a/handlers_drive.go
+++ b/handlers_drive.go
@@ -38,6 +38,19 @@ func downloadHandler(ctx cli.Context) {
     checkErr(err)
 }
 
+func downloadRevisionHandler(ctx cli.Context) {
+    args := ctx.Args()
+    err := newDrive(args).DownloadRevision(drive.DownloadRevisionArgs{
+        Out: os.Stdout,
+        FileId: args.String("fileId"),
+        RevisionId: args.String("revisionId"),
+        Force: args.Bool("force"),
+        Stdout: args.Bool("stdout"),
+        NoProgress: args.Bool("noProgress"),
+    })
+    checkErr(err)
+}
+
 func uploadHandler(ctx cli.Context) {
     args := ctx.Args()
     err := newDrive(args).Upload(drive.UploadFileArgs{