github.com/sberex/go-sberex@v1.8.2-0.20181113200658-ed96ac38f7d7/accounts/accounts.go (about) 1 // This file is part of the go-sberex library. The go-sberex library is 2 // free software: you can redistribute it and/or modify it under the terms 3 // of the GNU Lesser General Public License as published by the Free 4 // Software Foundation, either version 3 of the License, or (at your option) 5 // any later version. 6 // 7 // The go-sberex library is distributed in the hope that it will be useful, 8 // but WITHOUT ANY WARRANTY; without even the implied warranty of 9 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser 10 // General Public License <http://www.gnu.org/licenses/> for more details. 11 12 // Package accounts implements high level Sberex account management. 13 package accounts 14 15 import ( 16 "math/big" 17 18 sberex "github.com/Sberex/go-sberex" 19 "github.com/Sberex/go-sberex/common" 20 "github.com/Sberex/go-sberex/core/types" 21 "github.com/Sberex/go-sberex/event" 22 ) 23 24 // Account represents an Sberex account located at a specific location defined 25 // by the optional URL field. 26 type Account struct { 27 Address common.Address `json:"address"` // Sberex account address derived from the key 28 URL URL `json:"url"` // Optional resource locator within a backend 29 } 30 31 // Wallet represents a software or hardware wallet that might contain one or more 32 // accounts (derived from the same seed). 33 type Wallet interface { 34 // URL retrieves the canonical path under which this wallet is reachable. It is 35 // user by upper layers to define a sorting order over all wallets from multiple 36 // backends. 37 URL() URL 38 39 // Status returns a textual status to aid the user in the current state of the 40 // wallet. It also returns an error indicating any failure the wallet might have 41 // encountered. 42 Status() (string, error) 43 44 // Open initializes access to a wallet instance. It is not meant to unlock or 45 // decrypt account keys, rather simply to establish a connection to hardware 46 // wallets and/or to access derivation seeds. 47 // 48 // The passphrase parameter may or may not be used by the implementation of a 49 // particular wallet instance. The reason there is no passwordless open method 50 // is to strive towards a uniform wallet handling, oblivious to the different 51 // backend providers. 52 // 53 // Please note, if you open a wallet, you must close it to release any allocated 54 // resources (especially important when working with hardware wallets). 55 Open(passphrase string) error 56 57 // Close releases any resources held by an open wallet instance. 58 Close() error 59 60 // Accounts retrieves the list of signing accounts the wallet is currently aware 61 // of. For hierarchical deterministic wallets, the list will not be exhaustive, 62 // rather only contain the accounts explicitly pinned during account derivation. 63 Accounts() []Account 64 65 // Contains returns whether an account is part of this particular wallet or not. 66 Contains(account Account) bool 67 68 // Derive attempts to explicitly derive a hierarchical deterministic account at 69 // the specified derivation path. If requested, the derived account will be added 70 // to the wallet's tracked account list. 71 Derive(path DerivationPath, pin bool) (Account, error) 72 73 // SelfDerive sets a base account derivation path from which the wallet attempts 74 // to discover non zero accounts and automatically add them to list of tracked 75 // accounts. 76 // 77 // Note, self derivaton will increment the last component of the specified path 78 // opposed to decending into a child path to allow discovering accounts starting 79 // from non zero components. 80 // 81 // You can disable automatic account discovery by calling SelfDerive with a nil 82 // chain state reader. 83 SelfDerive(base DerivationPath, chain sberex.ChainStateReader) 84 85 // SignHash requests the wallet to sign the given hash. 86 // 87 // It looks up the account specified either solely via its address contained within, 88 // or optionally with the aid of any location metadata from the embedded URL field. 89 // 90 // If the wallet requires additional authentication to sign the request (e.g. 91 // a password to decrypt the account, or a PIN code o verify the transaction), 92 // an AuthNeededError instance will be returned, containing infos for the user 93 // about which fields or actions are needed. The user may retry by providing 94 // the needed details via SignHashWithPassphrase, or by other means (e.g. unlock 95 // the account in a keystore). 96 SignHash(account Account, hash []byte) ([]byte, error) 97 98 // SignTx requests the wallet to sign the given transaction. 99 // 100 // It looks up the account specified either solely via its address contained within, 101 // or optionally with the aid of any location metadata from the embedded URL field. 102 // 103 // If the wallet requires additional authentication to sign the request (e.g. 104 // a password to decrypt the account, or a PIN code o verify the transaction), 105 // an AuthNeededError instance will be returned, containing infos for the user 106 // about which fields or actions are needed. The user may retry by providing 107 // the needed details via SignTxWithPassphrase, or by other means (e.g. unlock 108 // the account in a keystore). 109 SignTx(account Account, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) 110 111 // SignHashWithPassphrase requests the wallet to sign the given hash with the 112 // given passphrase as extra authentication information. 113 // 114 // It looks up the account specified either solely via its address contained within, 115 // or optionally with the aid of any location metadata from the embedded URL field. 116 SignHashWithPassphrase(account Account, passphrase string, hash []byte) ([]byte, error) 117 118 // SignTxWithPassphrase requests the wallet to sign the given transaction, with the 119 // given passphrase as extra authentication information. 120 // 121 // It looks up the account specified either solely via its address contained within, 122 // or optionally with the aid of any location metadata from the embedded URL field. 123 SignTxWithPassphrase(account Account, passphrase string, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) 124 } 125 126 // Backend is a "wallet provider" that may contain a batch of accounts they can 127 // sign transactions with and upon request, do so. 128 type Backend interface { 129 // Wallets retrieves the list of wallets the backend is currently aware of. 130 // 131 // The returned wallets are not opened by default. For software HD wallets this 132 // means that no base seeds are decrypted, and for hardware wallets that no actual 133 // connection is established. 134 // 135 // The resulting wallet list will be sorted alphabetically based on its internal 136 // URL assigned by the backend. Since wallets (especially hardware) may come and 137 // go, the same wallet might appear at a different positions in the list during 138 // subsequent retrievals. 139 Wallets() []Wallet 140 141 // Subscribe creates an async subscription to receive notifications when the 142 // backend detects the arrival or departure of a wallet. 143 Subscribe(sink chan<- WalletEvent) event.Subscription 144 } 145 146 // WalletEventType represents the different event types that can be fired by 147 // the wallet subscription subsystem. 148 type WalletEventType int 149 150 const ( 151 // WalletArrived is fired when a new wallet is detected either via USB or via 152 // a filesystem event in the keystore. 153 WalletArrived WalletEventType = iota 154 155 // WalletOpened is fired when a wallet is successfully opened with the purpose 156 // of starting any background processes such as automatic key derivation. 157 WalletOpened 158 159 // WalletDropped 160 WalletDropped 161 ) 162 163 // WalletEvent is an event fired by an account backend when a wallet arrival or 164 // departure is detected. 165 type WalletEvent struct { 166 Wallet Wallet // Wallet instance arrived or departed 167 Kind WalletEventType // Event type that happened in the system 168 }