github.com/clem109/go-ethereum@v1.8.3-0.20180316121352-fe6cf00f480a/cmd/swarm/hash.go (about)

     1  // Copyright 2016 The go-ethereum Authors
     2  // This file is part of go-ethereum.
     3  //
     4  // go-ethereum is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // go-ethereum is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU General Public License
    15  // along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  // Command bzzhash computes a swarm tree hash.
    18  package main
    19  
    20  import (
    21  	"fmt"
    22  	"os"
    23  
    24  	"github.com/ethereum/go-ethereum/cmd/utils"
    25  	"github.com/ethereum/go-ethereum/swarm/storage"
    26  	"gopkg.in/urfave/cli.v1"
    27  )
    28  
    29  func hash(ctx *cli.Context) {
    30  	args := ctx.Args()
    31  	if len(args) < 1 {
    32  		utils.Fatalf("Usage: swarm hash <file name>")
    33  	}
    34  	f, err := os.Open(args[0])
    35  	if err != nil {
    36  		utils.Fatalf("Error opening file " + args[1])
    37  	}
    38  	defer f.Close()
    39  
    40  	stat, _ := f.Stat()
    41  	chunker := storage.NewTreeChunker(storage.NewChunkerParams())
    42  	key, err := chunker.Split(f, stat.Size(), nil, nil, nil)
    43  	if err != nil {
    44  		utils.Fatalf("%v\n", err)
    45  	} else {
    46  		fmt.Printf("%v\n", key)
    47  	}
    48  }