open-nomad/command/fs_cat.go

139 lines
3.1 KiB
Go

package command
import (
"fmt"
"io"
"os"
"strings"
)
type FSCatCommand struct {
Meta
}
func (f *FSCatCommand) Help() string {
helpText := `
Usage: nomad fs cat <alloc-id> <path>
Dispays a file in an allocation directory at the given path.
The path is relative to the allocation directory and defaults to root if unspecified.
General Options:
` + generalOptionsUsage() + `
Cat Options:
-verbose
Show full information.
`
return strings.TrimSpace(helpText)
}
func (f *FSCatCommand) Synopsis() string {
return "Cat a file in an allocation directory"
}
func (f *FSCatCommand) Run(args []string) int {
var verbose bool
flags := f.Meta.FlagSet("fs-list", FlagSetClient)
flags.Usage = func() { f.Ui.Output(f.Help()) }
flags.BoolVar(&verbose, "verbose", false, "")
if err := flags.Parse(args); err != nil {
return 1
}
args = flags.Args()
if len(args) < 1 {
f.Ui.Error("allocation id is a required parameter")
return 1
}
allocID := args[0]
path := "/"
if len(args) == 2 {
path = args[1]
}
client, err := f.Meta.Client()
if err != nil {
f.Ui.Error(fmt.Sprintf("Error inititalizing client: %v", err))
return 1
}
// Truncate the id unless full length is requested
length := shortId
if verbose {
length = fullId
}
// Query the allocation info
alloc, _, err := client.Allocations().Info(allocID, nil)
if err != nil {
if len(allocID) == 1 {
f.Ui.Error(fmt.Sprintf("Alloc ID must contain at least two characters."))
return 1
}
if len(allocID)%2 == 1 {
// Identifiers must be of even length, so we strip off the last byte
// to provide a consistent user experience.
allocID = allocID[:len(allocID)-1]
}
allocs, _, err := client.Allocations().PrefixList(allocID)
if err != nil {
f.Ui.Error(fmt.Sprintf("Error querying allocation: %v", err))
return 1
}
if len(allocs) == 0 {
f.Ui.Error(fmt.Sprintf("No allocation(s) with prefix or id %q found", allocID))
return 1
}
if len(allocs) > 1 {
// Format the allocs
out := make([]string, len(allocs)+1)
out[0] = "ID|Eval ID|Job ID|Task Group|Desired Status|Client Status"
for i, alloc := range allocs {
out[i+1] = fmt.Sprintf("%s|%s|%s|%s|%s|%s",
limit(alloc.ID, length),
limit(alloc.EvalID, length),
alloc.JobID,
alloc.TaskGroup,
alloc.DesiredStatus,
alloc.ClientStatus,
)
}
f.Ui.Output(fmt.Sprintf("Prefix matched multiple allocations\n\n%s", formatList(out)))
return 0
}
// Prefix lookup matched a single allocation
alloc, _, err = client.Allocations().Info(allocs[0].ID, nil)
if err != nil {
f.Ui.Error(fmt.Sprintf("Error querying allocation: %s", err))
return 1
}
}
// Stat the file to find it's size
file, _, err := client.AllocFS().Stat(alloc, path, nil)
if err != nil {
f.Ui.Error(err.Error())
return 1
}
if file.IsDir {
f.Ui.Error(fmt.Sprintf("The file %q is a directory", file.Name))
return 1
}
// Get the contents of the file
offset := 0
limit := file.Size
r, _, err := client.AllocFS().ReadAt(alloc, path, int64(offset), limit, nil)
if err != nil {
f.Ui.Error(fmt.Sprintf("Error reading file: %v", err))
return 1
}
io.Copy(os.Stdout, r)
return 0
}