forked from minio/mc
/
cat-main.go
116 lines (102 loc) · 3.38 KB
/
cat-main.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
/*
* Minio Client, (C) 2015 Minio, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package main
import (
"io"
"os"
"syscall"
"github.com/minio/cli"
"github.com/minio/mc/pkg/console"
"github.com/minio/minio/pkg/iodine"
)
// Help message.
var catCmd = cli.Command{
Name: "cat",
Usage: "Display contents of a file",
Action: runCatCmd,
CustomHelpTemplate: `NAME:
mc {{.Name}} - {{.Usage}}
USAGE:
mc {{.Name}}{{if .Flags}} [ARGS...]{{end}} SOURCE [SOURCE...] {{if .Description}}
DESCRIPTION:
{{.Description}}{{end}}{{if .Flags}}
FLAGS:
{{range .Flags}}{{.}}
{{end}}{{ end }}
EXAMPLES:
1. Concantenate an object from Amazon S3 object storage to mplayer standard input.
$ mc {{.Name}} https://s3.amazonaws.com/ferenginar/klingon_opera_aktuh_maylotah.ogg | mplayer -
2. Concantenate a file from local filesystem to standard output.
$ mc {{.Name}} khitomer-accords.txt
3. Concantenate multiple files from local filesystem to standard output.
$ mc {{.Name}} *.txt > newfile.txt
4. Concatenate a non english file name from Amazon S3 object storage.
$ mc {{.Name}} s3:andoria/本語 > /tmp/本語
`,
}
func runCatCmd(ctx *cli.Context) {
if !ctx.Args().Present() || ctx.Args().First() == "help" {
cli.ShowCommandHelpAndExit(ctx, "cat", 1) // last argument is exit code
}
if !isMcConfigExists() {
console.Fatalf("Please run \"mc config generate\". %s\n", errNotConfigured{})
}
config := mustGetMcConfig()
// Convert arguments to URLs: expand alias, fix format...
for _, arg := range ctx.Args() {
sourceURL, err := getExpandedURL(arg, config.Aliases)
if err != nil {
switch e := iodine.ToError(err).(type) {
case errUnsupportedScheme:
console.Fatalf("Unknown type of URL %s. %s\n", e.url, err)
default:
console.Fatalf("Unable to parse argument %s. %s\n", arg, err)
}
}
errorMsg, err := doCatCmd(sourceURL)
if err != nil {
console.Fatalln(errorMsg)
}
}
}
func doCatCmd(sourceURL string) (string, error) {
sourceClnt, err := source2Client(sourceURL)
if err != nil {
return "Unable to create client: " + sourceURL, NewIodine(iodine.New(err, nil))
}
// ignore size, since os.Stat() would not return proper size all the time for local filesystem
// for example /proc files.
reader, _, err := sourceClnt.GetObject(0, 0)
if err != nil {
return "Unable to retrieve file: " + sourceURL, NewIodine(iodine.New(err, nil))
}
defer reader.Close()
// read till EOF
_, err = io.Copy(os.Stdout, reader)
if err != nil {
switch e := iodine.ToError(err).(type) {
case *os.PathError:
if e.Err == syscall.EPIPE {
// stdout closed by the user. Gracefully exit.
return "", nil
}
return "Writing data to stdout failed, unexpected problem.. please report this error", iodine.New(err, nil)
default:
return "Reading data from source failed: " + sourceURL, NewIodine(iodine.New(err, nil))
}
}
return "", nil
}