github.com/cuiweixie/go-ethereum@v1.8.2-0.20180303084001-66cd41af1e38/swarm/api/uri.go (about)

     1  // Copyright 2017 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser 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  // The go-ethereum library 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 Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package api
    18  
    19  import (
    20  	"fmt"
    21  	"net/url"
    22  	"strings"
    23  )
    24  
    25  // URI is a reference to content stored in swarm.
    26  type URI struct {
    27  	// Scheme has one of the following values:
    28  	//
    29  	// * bzz           - an entry in a swarm manifest
    30  	// * bzz-raw       - raw swarm content
    31  	// * bzz-immutable - immutable URI of an entry in a swarm manifest
    32  	//                   (address is not resolved)
    33  	// * bzz-list      -  list of all files contained in a swarm manifest
    34  	//
    35  	// Deprecated Schemes:
    36  	// * bzzr - raw swarm content
    37  	// * bzzi - immutable URI of an entry in a swarm manifest
    38  	//          (address is not resolved)
    39  	// * bzz-hash - hash of swarm content
    40  	//
    41  	Scheme string
    42  
    43  	// Addr is either a hexadecimal storage key or it an address which
    44  	// resolves to a storage key
    45  	Addr string
    46  
    47  	// Path is the path to the content within a swarm manifest
    48  	Path string
    49  }
    50  
    51  // Parse parses rawuri into a URI struct, where rawuri is expected to have one
    52  // of the following formats:
    53  //
    54  // * <scheme>:/
    55  // * <scheme>:/<addr>
    56  // * <scheme>:/<addr>/<path>
    57  // * <scheme>://
    58  // * <scheme>://<addr>
    59  // * <scheme>://<addr>/<path>
    60  //
    61  // with scheme one of bzz, bzz-raw, bzz-immutable, bzz-list or bzz-hash
    62  // or deprecated ones bzzr and bzzi
    63  func Parse(rawuri string) (*URI, error) {
    64  	u, err := url.Parse(rawuri)
    65  	if err != nil {
    66  		return nil, err
    67  	}
    68  	uri := &URI{Scheme: u.Scheme}
    69  
    70  	// check the scheme is valid
    71  	switch uri.Scheme {
    72  	case "bzz", "bzz-raw", "bzz-immutable", "bzz-list", "bzz-hash", "bzzr", "bzzi":
    73  	default:
    74  		return nil, fmt.Errorf("unknown scheme %q", u.Scheme)
    75  	}
    76  
    77  	// handle URIs like bzz://<addr>/<path> where the addr and path
    78  	// have already been split by url.Parse
    79  	if u.Host != "" {
    80  		uri.Addr = u.Host
    81  		uri.Path = strings.TrimLeft(u.Path, "/")
    82  		return uri, nil
    83  	}
    84  
    85  	// URI is like bzz:/<addr>/<path> so split the addr and path from
    86  	// the raw path (which will be /<addr>/<path>)
    87  	parts := strings.SplitN(strings.TrimLeft(u.Path, "/"), "/", 2)
    88  	uri.Addr = parts[0]
    89  	if len(parts) == 2 {
    90  		uri.Path = parts[1]
    91  	}
    92  	return uri, nil
    93  }
    94  
    95  func (u *URI) Raw() bool {
    96  	return u.Scheme == "bzz-raw"
    97  }
    98  
    99  func (u *URI) Immutable() bool {
   100  	return u.Scheme == "bzz-immutable"
   101  }
   102  
   103  func (u *URI) List() bool {
   104  	return u.Scheme == "bzz-list"
   105  }
   106  
   107  func (u *URI) DeprecatedRaw() bool {
   108  	return u.Scheme == "bzzr"
   109  }
   110  
   111  func (u *URI) DeprecatedImmutable() bool {
   112  	return u.Scheme == "bzzi"
   113  }
   114  
   115  func (u *URI) Hash() bool {
   116  	return u.Scheme == "bzz-hash"
   117  }
   118  
   119  func (u *URI) String() string {
   120  	return u.Scheme + ":/" + u.Addr + "/" + u.Path
   121  }