copyurl: add option to print resulting auto-filename (#5095)

Fixes #5094

cmd/copyurl/copyurl.go

@@ -3,6 +3,7 @@ package copyurl
 import (
 	"context"
 	"errors"
+	"fmt"
 	"os"
 
 	"github.com/rclone/rclone/cmd"
@@ -13,15 +14,17 @@ import (
 )
 
 var (
-	autoFilename = false
-	stdout       = false
-	noClobber    = false
+	autoFilename  = false
+	printFilename = false
+	stdout        = false
+	noClobber     = false
 )
 
 func init() {
 	cmd.Root.AddCommand(commandDefinition)
 	cmdFlags := commandDefinition.Flags()
 	flags.BoolVarP(cmdFlags, &autoFilename, "auto-filename", "a", autoFilename, "Get the file name from the URL and use it for destination file path")
+	flags.BoolVarP(cmdFlags, &printFilename, "print-filename", "p", printFilename, "Print the resulting name from --auto-filename")
 	flags.BoolVarP(cmdFlags, &noClobber, "no-clobber", "", noClobber, "Prevent overwriting file with same name")
 	flags.BoolVarP(cmdFlags, &stdout, "stdout", "", stdout, "Write the output to stdout rather than a file")
 }
@@ -33,15 +36,16 @@ var commandDefinition = &cobra.Command{
 Download a URL's content and copy it to the destination without saving
 it in temporary storage.
 
-Setting --auto-filename will cause the file name to be retrieved from
+Setting ` + "`--auto-filename`" + `will cause the file name to be retrieved from
 the from URL (after any redirections) and used in the destination
-path.
+path. With ` + "`--print-filename`" + ` in addition, the resuling file name will
+be printed.
 
-Setting --no-clobber will prevent overwriting file on the 
+Setting ` + "`--no-clobber`" + ` will prevent overwriting file on the 
 destination if there is one with the same name.
 
-Setting --stdout or making the output file name "-" will cause the
-output to be written to standard output.
+Setting ` + "`--stdout`" + ` or making the output file name ` + "`-`" + `
+will cause the output to be written to standard output.
 `,
 	RunE: func(command *cobra.Command, args []string) (err error) {
 		cmd.CheckArgs(1, 2, command, args)
@@ -61,10 +65,14 @@ output to be written to standard output.
 			}
 		}
 		cmd.Run(true, true, command, func() error {
+			var dst fs.Object
 			if stdout {
 				err = operations.CopyURLToWriter(context.Background(), args[0], os.Stdout)
 			} else {
-				_, err = operations.CopyURL(context.Background(), fsdst, dstFileName, args[0], autoFilename, noClobber)
+				dst, err = operations.CopyURL(context.Background(), fsdst, dstFileName, args[0], autoFilename, noClobber)
+				if printFilename && err == nil && dst != nil {
+					fmt.Println(dst.Remote())
+				}
 			}
 			return err
 		})

fs/operations/operations.go

@@ -1635,6 +1635,7 @@ func copyURLFn(ctx context.Context, dstFileName string, url string, dstFileNameF
 		if dstFileName == "." || dstFileName == "/" {
 			return errors.Errorf("CopyURL failed: file name wasn't found in url")
 		}
+		fs.Debugf(dstFileName, "File name found in url")
 	}
 	return fn(ctx, dstFileName, resp.Body, resp.ContentLength, modTime)
 }