github.com/minio/mc@v0.0.0-20240503112107-b471de8d1882/cmd/get-main.go (about)

     1  // Copyright (c) 2015-2024 MinIO, Inc.
     2  //
     3  // This file is part of MinIO Object Storage stack
     4  //
     5  // This program is free software: you can redistribute it and/or modify
     6  // it under the terms of the GNU Affero General Public License as published by
     7  // the Free Software Foundation, either version 3 of the License, or
     8  // (at your option) any later version.
     9  //
    10  // This program is distributed in the hope that it will be useful
    11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    13  // GNU Affero General Public License for more details.
    14  //
    15  // You should have received a copy of the GNU Affero General Public License
    16  // along with this program.  If not, see <http://www.gnu.org/licenses/>.
    17  
    18  package cmd
    19  
    20  import (
    21  	"context"
    22  	"strings"
    23  
    24  	"github.com/minio/cli"
    25  	"github.com/minio/pkg/v2/console"
    26  )
    27  
    28  // get command flags.
    29  var (
    30  	getFlags = []cli.Flag{}
    31  )
    32  
    33  // Get command.
    34  var getCmd = cli.Command{
    35  	Name:         "get",
    36  	Usage:        "get s3 object to local",
    37  	Action:       mainGet,
    38  	OnUsageError: onUsageError,
    39  	Before:       setGlobalsFromContext,
    40  	Flags:        append(append(globalFlags, encCFlag), getFlags...),
    41  	CustomHelpTemplate: `NAME:
    42    {{.HelpName}} - {{.Usage}}
    43  
    44  USAGE:
    45    {{.HelpName}} [FLAGS] SOURCE TARGET
    46  
    47  FLAGS:
    48    {{range .VisibleFlags}}{{.}}
    49    {{end}}
    50  
    51  EXAMPLES:
    52    1. Get an object from MinIO storage to local file system
    53      {{.Prompt}} {{.HelpName}} play/mybucket/object path-to/object
    54  
    55    2. Get an object from MinIO storage using encryption
    56      {{.Prompt}} {{.HelpName}} --enc-c "play/mybucket/object=MDEyMzQ1Njc4OTAxMjM0NTY3ODkwMTIzNDU2Nzg5MDA" play/mybucket/object path-to/object
    57  `,
    58  }
    59  
    60  // mainGet is the entry point for get command.
    61  func mainGet(cliCtx *cli.Context) (e error) {
    62  	args := cliCtx.Args()
    63  	if len(args) != 2 {
    64  		showCommandHelpAndExit(cliCtx, 1) // last argument is exit code.
    65  	}
    66  
    67  	ctx, cancelGet := context.WithCancel(globalContext)
    68  	defer cancelGet()
    69  
    70  	encryptionKeys, err := validateAndCreateEncryptionKeys(cliCtx)
    71  	if err != nil {
    72  		err.Trace(cliCtx.Args()...)
    73  	}
    74  	fatalIf(err, "unable to parse encryption keys")
    75  
    76  	// get source and target
    77  	sourceURLs := args[:len(args)-1]
    78  	targetURL := args[len(args)-1]
    79  
    80  	getURLsCh := make(chan URLs, 10000)
    81  	var totalObjects, totalBytes int64
    82  
    83  	// Store a progress bar or an accounter
    84  	var pg ProgressReader
    85  	// Enable progress bar reader only during default mode.
    86  	if !globalQuiet && !globalJSON { // set up progress bar
    87  		pg = newProgressBar(totalBytes)
    88  	} else {
    89  		pg = newAccounter(totalBytes)
    90  	}
    91  	go func() {
    92  		opts := prepareCopyURLsOpts{
    93  			sourceURLs:              sourceURLs,
    94  			targetURL:               targetURL,
    95  			encKeyDB:                encryptionKeys,
    96  			ignoreBucketExistsCheck: true,
    97  		}
    98  
    99  		for getURLs := range prepareGetURLs(ctx, opts) {
   100  			if getURLs.Error != nil {
   101  				getURLsCh <- getURLs
   102  				break
   103  			}
   104  			totalObjects++
   105  			getURLsCh <- getURLs
   106  		}
   107  		close(getURLsCh)
   108  	}()
   109  	for {
   110  		select {
   111  		case <-ctx.Done():
   112  			showLastProgressBar(pg, nil)
   113  			return
   114  		case getURLs, ok := <-getURLsCh:
   115  			if !ok {
   116  				showLastProgressBar(pg, nil)
   117  				return
   118  			}
   119  			if getURLs.Error != nil {
   120  				printGetURLsError(&getURLs)
   121  				showLastProgressBar(pg, getURLs.Error.ToGoError())
   122  				return
   123  			}
   124  			urls := doCopy(ctx, doCopyOpts{
   125  				cpURLs:              getURLs,
   126  				pg:                  pg,
   127  				encryptionKeys:      encryptionKeys,
   128  				updateProgressTotal: true,
   129  			})
   130  			if urls.Error != nil {
   131  				e = urls.Error.ToGoError()
   132  				showLastProgressBar(pg, e)
   133  				return
   134  			}
   135  		}
   136  	}
   137  }
   138  
   139  func printGetURLsError(cpURLs *URLs) {
   140  	// Print in new line and adjust to top so that we
   141  	// don't print over the ongoing scan bar
   142  	if !globalQuiet && !globalJSON {
   143  		console.Eraseline()
   144  	}
   145  
   146  	if strings.Contains(cpURLs.Error.ToGoError().Error(),
   147  		" is a folder.") {
   148  		errorIf(cpURLs.Error.Trace(),
   149  			"Folder cannot be copied. Please use `...` suffix.")
   150  	} else {
   151  		errorIf(cpURLs.Error.Trace(),
   152  			"Unable to download.")
   153  	}
   154  }