rclone/cmd/cat/cat.go
Nick Craig-Wood 11da2a6c9b Break the fs package up into smaller parts.
The purpose of this is to make it easier to maintain and eventually to
allow the rclone backends to be re-used in other projects without
having to use the rclone configuration system.

The new code layout is documented in CONTRIBUTING.
2018-01-15 17:51:14 +00:00

81 lines
2.2 KiB
Go

package cat
import (
"io"
"io/ioutil"
"log"
"os"
"github.com/ncw/rclone/cmd"
"github.com/ncw/rclone/fs/operations"
"github.com/spf13/cobra"
)
// Globals
var (
head = int64(0)
tail = int64(0)
offset = int64(0)
count = int64(-1)
discard = false
)
func init() {
cmd.Root.AddCommand(commandDefintion)
commandDefintion.Flags().Int64VarP(&head, "head", "", head, "Only print the first N characters.")
commandDefintion.Flags().Int64VarP(&tail, "tail", "", tail, "Only print the last N characters.")
commandDefintion.Flags().Int64VarP(&offset, "offset", "", offset, "Start printing at offset N (or from end if -ve).")
commandDefintion.Flags().Int64VarP(&count, "count", "", count, "Only print N characters.")
commandDefintion.Flags().BoolVarP(&discard, "discard", "", discard, "Discard the output instead of printing.")
}
var commandDefintion = &cobra.Command{
Use: "cat remote:path",
Short: `Concatenates any files and sends them to stdout.`,
Long: `
rclone cat sends any files to standard output.
You can use it like this to output a single file
rclone cat remote:path/to/file
Or like this to output any file in dir or subdirectories.
rclone cat remote:path/to/dir
Or like this to output any .txt files in dir or subdirectories.
rclone --include "*.txt" cat remote:path/to/dir
Use the --head flag to print characters only at the start, --tail for
the end and --offset and --count to print a section in the middle.
Note that if offset is negative it will count from the end, so
--offset -1 --count 1 is equivalent to --tail 1.
`,
Run: func(command *cobra.Command, args []string) {
usedOffset := offset != 0 || count >= 0
usedHead := head > 0
usedTail := tail > 0
if usedHead && usedTail || usedHead && usedOffset || usedTail && usedOffset {
log.Fatalf("Can only use one of --head, --tail or --offset with --count")
}
if head > 0 {
offset = 0
count = head
}
if tail > 0 {
offset = -tail
count = -1
}
cmd.CheckArgs(1, 1, command, args)
fsrc := cmd.NewFsSrc(args)
var w io.Writer = os.Stdout
if discard {
w = ioutil.Discard
}
cmd.Run(false, false, command, func() error {
return operations.Cat(fsrc, w, offset, count)
})
},
}