以太坊(eth)交易所钱包开发 - 8 - erc20代币检测

erc20 简介

erc20代币实际上就是实现了erc20接口的eth合约。例如我们常见的币种都实现了erc20的接口,例如

  • Tether USD (USDT)
  • BNB (BNB)
  • HuobiToken (HT)
  • OKB (OKB)

erc20的接口代码是这样的

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
pragma solidity ^0.4.24;

contract ERC20 {
// 合约名 例如 Tether USD
string public constant name = "";
// 单位名 例如 USDT
string public constant symbol = "";
// 小数点后位数 例如 6
uint8 public constant decimals = 0;

// 代币总数额
function totalSupply() public constant returns (uint);
// 返回某个地址tokenOwner的代币数额
function balanceOf(address tokenOwner) public constant returns (uint balance);
// 返回地址address允许地址tokenOwner提取的代币数额
function allowance(address tokenOwner, address spender) public constant returns (uint remaining);
// 将调用者的tokens数额的代币转账给地址to
function transfer(address to, uint tokens) public returns (bool success);
// 允许调用者的tokens数额代币共地址spender提取
function approve(address spender, uint tokens) public returns (bool success);
// 从地址from中转账tokens数额的代币给地址to
function transferFrom(address from, address to, uint tokens) public returns (bool success);
// 发生代币转账时候的通知,存放于log中
event Transfer(address indexed from, address indexed to, uint tokens);
// 发生允许他人提取自己的代币时候的通知,存放于log中
event Approval(address indexed tokenOwner, address indexed spender, uint tokens);
}

使用solc工具可以生成abi文件,abi文件本质上就是描述接口的json文件。erc20接口的abi文件如下:

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
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
[
{
"constant": true,
"inputs": [],
"name": "name",
"outputs": [
{
"name": "",
"type": "string"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": false,
"inputs": [
{
"name": "_spender",
"type": "address"
},
{
"name": "_value",
"type": "uint256"
}
],
"name": "approve",
"outputs": [
{
"name": "",
"type": "bool"
}
],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"constant": true,
"inputs": [],
"name": "totalSupply",
"outputs": [
{
"name": "",
"type": "uint256"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": false,
"inputs": [
{
"name": "_from",
"type": "address"
},
{
"name": "_to",
"type": "address"
},
{
"name": "_value",
"type": "uint256"
}
],
"name": "transferFrom",
"outputs": [
{
"name": "",
"type": "bool"
}
],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"constant": true,
"inputs": [],
"name": "decimals",
"outputs": [
{
"name": "",
"type": "uint8"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": true,
"inputs": [
{
"name": "_owner",
"type": "address"
}
],
"name": "balanceOf",
"outputs": [
{
"name": "balance",
"type": "uint256"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": true,
"inputs": [],
"name": "symbol",
"outputs": [
{
"name": "",
"type": "string"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": false,
"inputs": [
{
"name": "_to",
"type": "address"
},
{
"name": "_value",
"type": "uint256"
}
],
"name": "transfer",
"outputs": [
{
"name": "",
"type": "bool"
}
],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"constant": true,
"inputs": [
{
"name": "_owner",
"type": "address"
},
{
"name": "_spender",
"type": "address"
}
],
"name": "allowance",
"outputs": [
{
"name": "",
"type": "uint256"
}
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"payable": true,
"stateMutability": "payable",
"type": "fallback"
},
{
"anonymous": false,
"inputs": [
{
"indexed": true,
"name": "owner",
"type": "address"
},
{
"indexed": true,
"name": "spender",
"type": "address"
},
{
"indexed": false,
"name": "value",
"type": "uint256"
}
],
"name": "Approval",
"type": "event"
},
{
"anonymous": false,
"inputs": [
{
"indexed": true,
"name": "from",
"type": "address"
},
{
"indexed": true,
"name": "to",
"type": "address"
},
{
"indexed": false,
"name": "value",
"type": "uint256"
}
],
"name": "Transfer",
"type": "event"
}
]

之后abigen工具可以通过abi文件生成一个对应的go源码,这里我已经生成好了:

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
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
// Code generated - DO NOT EDIT.
// This file is a generated binding and any manual changes will be lost.

package eth

import (
"math/big"
"strings"

ethereum "github.com/ethereum/go-ethereum"
"github.com/ethereum/go-ethereum/accounts/abi"
"github.com/ethereum/go-ethereum/accounts/abi/bind"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/event"
)

// Reference imports to suppress errors if they are not otherwise used.
var (
_ = big.NewInt
_ = strings.NewReader
_ = ethereum.NotFound
_ = abi.U256
_ = bind.Bind
_ = common.Big1
_ = types.BloomLookup
_ = event.NewSubscription
)

// EthABI is the input ABI used to generate the binding from.
const EthABI = "[{\"constant\":true,\"inputs\":[],\"name\":\"name\",\"outputs\":[{\"name\":\"\",\"type\":\"string\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"spender\",\"type\":\"address\"},{\"name\":\"tokens\",\"type\":\"uint256\"}],\"name\":\"approve\",\"outputs\":[{\"name\":\"success\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[],\"name\":\"totalSupply\",\"outputs\":[{\"name\":\"\",\"type\":\"uint256\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"from\",\"type\":\"address\"},{\"name\":\"to\",\"type\":\"address\"},{\"name\":\"tokens\",\"type\":\"uint256\"}],\"name\":\"transferFrom\",\"outputs\":[{\"name\":\"success\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[],\"name\":\"decimals\",\"outputs\":[{\"name\":\"\",\"type\":\"uint8\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[{\"name\":\"tokenOwner\",\"type\":\"address\"}],\"name\":\"balanceOf\",\"outputs\":[{\"name\":\"balance\",\"type\":\"uint256\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[],\"name\":\"symbol\",\"outputs\":[{\"name\":\"\",\"type\":\"string\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"to\",\"type\":\"address\"},{\"name\":\"tokens\",\"type\":\"uint256\"}],\"name\":\"transfer\",\"outputs\":[{\"name\":\"success\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[{\"name\":\"tokenOwner\",\"type\":\"address\"},{\"name\":\"spender\",\"type\":\"address\"}],\"name\":\"allowance\",\"outputs\":[{\"name\":\"remaining\",\"type\":\"uint256\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"name\":\"from\",\"type\":\"address\"},{\"indexed\":true,\"name\":\"to\",\"type\":\"address\"},{\"indexed\":false,\"name\":\"tokens\",\"type\":\"uint256\"}],\"name\":\"Transfer\",\"type\":\"event\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"name\":\"tokenOwner\",\"type\":\"address\"},{\"indexed\":true,\"name\":\"spender\",\"type\":\"address\"},{\"indexed\":false,\"name\":\"tokens\",\"type\":\"uint256\"}],\"name\":\"Approval\",\"type\":\"event\"}]"

// Eth is an auto generated Go binding around an Ethereum contract.
type Eth struct {
EthCaller // Read-only binding to the contract
EthTransactor // Write-only binding to the contract
EthFilterer // Log filterer for contract events
}

// EthCaller is an auto generated read-only Go binding around an Ethereum contract.
type EthCaller struct {
contract *bind.BoundContract // Generic contract wrapper for the low level calls
}

// EthTransactor is an auto generated write-only Go binding around an Ethereum contract.
type EthTransactor struct {
contract *bind.BoundContract // Generic contract wrapper for the low level calls
}

// EthFilterer is an auto generated log filtering Go binding around an Ethereum contract events.
type EthFilterer struct {
contract *bind.BoundContract // Generic contract wrapper for the low level calls
}

// EthSession is an auto generated Go binding around an Ethereum contract,
// with pre-set call and transact options.
type EthSession struct {
Contract *Eth // Generic contract binding to set the session for
CallOpts bind.CallOpts // Call options to use throughout this session
TransactOpts bind.TransactOpts // Transaction auth options to use throughout this session
}

// EthCallerSession is an auto generated read-only Go binding around an Ethereum contract,
// with pre-set call options.
type EthCallerSession struct {
Contract *EthCaller // Generic contract caller binding to set the session for
CallOpts bind.CallOpts // Call options to use throughout this session
}

// EthTransactorSession is an auto generated write-only Go binding around an Ethereum contract,
// with pre-set transact options.
type EthTransactorSession struct {
Contract *EthTransactor // Generic contract transactor binding to set the session for
TransactOpts bind.TransactOpts // Transaction auth options to use throughout this session
}

// EthRaw is an auto generated low-level Go binding around an Ethereum contract.
type EthRaw struct {
Contract *Eth // Generic contract binding to access the raw methods on
}

// EthCallerRaw is an auto generated low-level read-only Go binding around an Ethereum contract.
type EthCallerRaw struct {
Contract *EthCaller // Generic read-only contract binding to access the raw methods on
}

// EthTransactorRaw is an auto generated low-level write-only Go binding around an Ethereum contract.
type EthTransactorRaw struct {
Contract *EthTransactor // Generic write-only contract binding to access the raw methods on
}

// NewEth creates a new instance of Eth, bound to a specific deployed contract.
func NewEth(address common.Address, backend bind.ContractBackend) (*Eth, error) {
contract, err := bindEth(address, backend, backend, backend)
if err != nil {
return nil, err
}
return &Eth{EthCaller: EthCaller{contract: contract}, EthTransactor: EthTransactor{contract: contract}, EthFilterer: EthFilterer{contract: contract}}, nil
}

// NewEthCaller creates a new read-only instance of Eth, bound to a specific deployed contract.
func NewEthCaller(address common.Address, caller bind.ContractCaller) (*EthCaller, error) {
contract, err := bindEth(address, caller, nil, nil)
if err != nil {
return nil, err
}
return &EthCaller{contract: contract}, nil
}

// NewEthTransactor creates a new write-only instance of Eth, bound to a specific deployed contract.
func NewEthTransactor(address common.Address, transactor bind.ContractTransactor) (*EthTransactor, error) {
contract, err := bindEth(address, nil, transactor, nil)
if err != nil {
return nil, err
}
return &EthTransactor{contract: contract}, nil
}

// NewEthFilterer creates a new log filterer instance of Eth, bound to a specific deployed contract.
func NewEthFilterer(address common.Address, filterer bind.ContractFilterer) (*EthFilterer, error) {
contract, err := bindEth(address, nil, nil, filterer)
if err != nil {
return nil, err
}
return &EthFilterer{contract: contract}, nil
}

// bindEth binds a generic wrapper to an already deployed contract.
func bindEth(address common.Address, caller bind.ContractCaller, transactor bind.ContractTransactor, filterer bind.ContractFilterer) (*bind.BoundContract, error) {
parsed, err := abi.JSON(strings.NewReader(EthABI))
if err != nil {
return nil, err
}
return bind.NewBoundContract(address, parsed, caller, transactor, filterer), nil
}

// Call invokes the (constant) contract method with params as input values and
// sets the output to result. The result type might be a single field for simple
// returns, a slice of interfaces for anonymous returns and a struct for named
// returns.
func (_Eth *EthRaw) Call(opts *bind.CallOpts, result interface{}, method string, params ...interface{}) error {
return _Eth.Contract.EthCaller.contract.Call(opts, result, method, params...)
}

// Transfer initiates a plain transaction to move funds to the contract, calling
// its default method if one is available.
func (_Eth *EthRaw) Transfer(opts *bind.TransactOpts) (*types.Transaction, error) {
return _Eth.Contract.EthTransactor.contract.Transfer(opts)
}

// Transact invokes the (paid) contract method with params as input values.
func (_Eth *EthRaw) Transact(opts *bind.TransactOpts, method string, params ...interface{}) (*types.Transaction, error) {
return _Eth.Contract.EthTransactor.contract.Transact(opts, method, params...)
}

// Call invokes the (constant) contract method with params as input values and
// sets the output to result. The result type might be a single field for simple
// returns, a slice of interfaces for anonymous returns and a struct for named
// returns.
func (_Eth *EthCallerRaw) Call(opts *bind.CallOpts, result interface{}, method string, params ...interface{}) error {
return _Eth.Contract.contract.Call(opts, result, method, params...)
}

// Transfer initiates a plain transaction to move funds to the contract, calling
// its default method if one is available.
func (_Eth *EthTransactorRaw) Transfer(opts *bind.TransactOpts) (*types.Transaction, error) {
return _Eth.Contract.contract.Transfer(opts)
}

// Transact invokes the (paid) contract method with params as input values.
func (_Eth *EthTransactorRaw) Transact(opts *bind.TransactOpts, method string, params ...interface{}) (*types.Transaction, error) {
return _Eth.Contract.contract.Transact(opts, method, params...)
}

// Allowance is a free data retrieval call binding the contract method 0xdd62ed3e.
//
// Solidity: function allowance(address tokenOwner, address spender) view returns(uint256 remaining)
func (_Eth *EthCaller) Allowance(opts *bind.CallOpts, tokenOwner common.Address, spender common.Address) (*big.Int, error) {
var (
ret0 = new(*big.Int)
)
out := ret0
err := _Eth.contract.Call(opts, out, "allowance", tokenOwner, spender)
return *ret0, err
}

// Allowance is a free data retrieval call binding the contract method 0xdd62ed3e.
//
// Solidity: function allowance(address tokenOwner, address spender) view returns(uint256 remaining)
func (_Eth *EthSession) Allowance(tokenOwner common.Address, spender common.Address) (*big.Int, error) {
return _Eth.Contract.Allowance(&_Eth.CallOpts, tokenOwner, spender)
}

// Allowance is a free data retrieval call binding the contract method 0xdd62ed3e.
//
// Solidity: function allowance(address tokenOwner, address spender) view returns(uint256 remaining)
func (_Eth *EthCallerSession) Allowance(tokenOwner common.Address, spender common.Address) (*big.Int, error) {
return _Eth.Contract.Allowance(&_Eth.CallOpts, tokenOwner, spender)
}

// BalanceOf is a free data retrieval call binding the contract method 0x70a08231.
//
// Solidity: function balanceOf(address tokenOwner) view returns(uint256 balance)
func (_Eth *EthCaller) BalanceOf(opts *bind.CallOpts, tokenOwner common.Address) (*big.Int, error) {
var (
ret0 = new(*big.Int)
)
out := ret0
err := _Eth.contract.Call(opts, out, "balanceOf", tokenOwner)
return *ret0, err
}

// BalanceOf is a free data retrieval call binding the contract method 0x70a08231.
//
// Solidity: function balanceOf(address tokenOwner) view returns(uint256 balance)
func (_Eth *EthSession) BalanceOf(tokenOwner common.Address) (*big.Int, error) {
return _Eth.Contract.BalanceOf(&_Eth.CallOpts, tokenOwner)
}

// BalanceOf is a free data retrieval call binding the contract method 0x70a08231.
//
// Solidity: function balanceOf(address tokenOwner) view returns(uint256 balance)
func (_Eth *EthCallerSession) BalanceOf(tokenOwner common.Address) (*big.Int, error) {
return _Eth.Contract.BalanceOf(&_Eth.CallOpts, tokenOwner)
}

// Decimals is a free data retrieval call binding the contract method 0x313ce567.
//
// Solidity: function decimals() view returns(uint8)
func (_Eth *EthCaller) Decimals(opts *bind.CallOpts) (uint8, error) {
var (
ret0 = new(uint8)
)
out := ret0
err := _Eth.contract.Call(opts, out, "decimals")
return *ret0, err
}

// Decimals is a free data retrieval call binding the contract method 0x313ce567.
//
// Solidity: function decimals() view returns(uint8)
func (_Eth *EthSession) Decimals() (uint8, error) {
return _Eth.Contract.Decimals(&_Eth.CallOpts)
}

// Decimals is a free data retrieval call binding the contract method 0x313ce567.
//
// Solidity: function decimals() view returns(uint8)
func (_Eth *EthCallerSession) Decimals() (uint8, error) {
return _Eth.Contract.Decimals(&_Eth.CallOpts)
}

// Name is a free data retrieval call binding the contract method 0x06fdde03.
//
// Solidity: function name() view returns(string)
func (_Eth *EthCaller) Name(opts *bind.CallOpts) (string, error) {
var (
ret0 = new(string)
)
out := ret0
err := _Eth.contract.Call(opts, out, "name")
return *ret0, err
}

// Name is a free data retrieval call binding the contract method 0x06fdde03.
//
// Solidity: function name() view returns(string)
func (_Eth *EthSession) Name() (string, error) {
return _Eth.Contract.Name(&_Eth.CallOpts)
}

// Name is a free data retrieval call binding the contract method 0x06fdde03.
//
// Solidity: function name() view returns(string)
func (_Eth *EthCallerSession) Name() (string, error) {
return _Eth.Contract.Name(&_Eth.CallOpts)
}

// Symbol is a free data retrieval call binding the contract method 0x95d89b41.
//
// Solidity: function symbol() view returns(string)
func (_Eth *EthCaller) Symbol(opts *bind.CallOpts) (string, error) {
var (
ret0 = new(string)
)
out := ret0
err := _Eth.contract.Call(opts, out, "symbol")
return *ret0, err
}

// Symbol is a free data retrieval call binding the contract method 0x95d89b41.
//
// Solidity: function symbol() view returns(string)
func (_Eth *EthSession) Symbol() (string, error) {
return _Eth.Contract.Symbol(&_Eth.CallOpts)
}

// Symbol is a free data retrieval call binding the contract method 0x95d89b41.
//
// Solidity: function symbol() view returns(string)
func (_Eth *EthCallerSession) Symbol() (string, error) {
return _Eth.Contract.Symbol(&_Eth.CallOpts)
}

// TotalSupply is a free data retrieval call binding the contract method 0x18160ddd.
//
// Solidity: function totalSupply() view returns(uint256)
func (_Eth *EthCaller) TotalSupply(opts *bind.CallOpts) (*big.Int, error) {
var (
ret0 = new(*big.Int)
)
out := ret0
err := _Eth.contract.Call(opts, out, "totalSupply")
return *ret0, err
}

// TotalSupply is a free data retrieval call binding the contract method 0x18160ddd.
//
// Solidity: function totalSupply() view returns(uint256)
func (_Eth *EthSession) TotalSupply() (*big.Int, error) {
return _Eth.Contract.TotalSupply(&_Eth.CallOpts)
}

// TotalSupply is a free data retrieval call binding the contract method 0x18160ddd.
//
// Solidity: function totalSupply() view returns(uint256)
func (_Eth *EthCallerSession) TotalSupply() (*big.Int, error) {
return _Eth.Contract.TotalSupply(&_Eth.CallOpts)
}

// Approve is a paid mutator transaction binding the contract method 0x095ea7b3.
//
// Solidity: function approve(address spender, uint256 tokens) returns(bool success)
func (_Eth *EthTransactor) Approve(opts *bind.TransactOpts, spender common.Address, tokens *big.Int) (*types.Transaction, error) {
return _Eth.contract.Transact(opts, "approve", spender, tokens)
}

// Approve is a paid mutator transaction binding the contract method 0x095ea7b3.
//
// Solidity: function approve(address spender, uint256 tokens) returns(bool success)
func (_Eth *EthSession) Approve(spender common.Address, tokens *big.Int) (*types.Transaction, error) {
return _Eth.Contract.Approve(&_Eth.TransactOpts, spender, tokens)
}

// Approve is a paid mutator transaction binding the contract method 0x095ea7b3.
//
// Solidity: function approve(address spender, uint256 tokens) returns(bool success)
func (_Eth *EthTransactorSession) Approve(spender common.Address, tokens *big.Int) (*types.Transaction, error) {
return _Eth.Contract.Approve(&_Eth.TransactOpts, spender, tokens)
}

// Transfer is a paid mutator transaction binding the contract method 0xa9059cbb.
//
// Solidity: function transfer(address to, uint256 tokens) returns(bool success)
func (_Eth *EthTransactor) Transfer(opts *bind.TransactOpts, to common.Address, tokens *big.Int) (*types.Transaction, error) {
return _Eth.contract.Transact(opts, "transfer", to, tokens)
}

// Transfer is a paid mutator transaction binding the contract method 0xa9059cbb.
//
// Solidity: function transfer(address to, uint256 tokens) returns(bool success)
func (_Eth *EthSession) Transfer(to common.Address, tokens *big.Int) (*types.Transaction, error) {
return _Eth.Contract.Transfer(&_Eth.TransactOpts, to, tokens)
}

// Transfer is a paid mutator transaction binding the contract method 0xa9059cbb.
//
// Solidity: function transfer(address to, uint256 tokens) returns(bool success)
func (_Eth *EthTransactorSession) Transfer(to common.Address, tokens *big.Int) (*types.Transaction, error) {
return _Eth.Contract.Transfer(&_Eth.TransactOpts, to, tokens)
}

// TransferFrom is a paid mutator transaction binding the contract method 0x23b872dd.
//
// Solidity: function transferFrom(address from, address to, uint256 tokens) returns(bool success)
func (_Eth *EthTransactor) TransferFrom(opts *bind.TransactOpts, from common.Address, to common.Address, tokens *big.Int) (*types.Transaction, error) {
return _Eth.contract.Transact(opts, "transferFrom", from, to, tokens)
}

// TransferFrom is a paid mutator transaction binding the contract method 0x23b872dd.
//
// Solidity: function transferFrom(address from, address to, uint256 tokens) returns(bool success)
func (_Eth *EthSession) TransferFrom(from common.Address, to common.Address, tokens *big.Int) (*types.Transaction, error) {
return _Eth.Contract.TransferFrom(&_Eth.TransactOpts, from, to, tokens)
}

// TransferFrom is a paid mutator transaction binding the contract method 0x23b872dd.
//
// Solidity: function transferFrom(address from, address to, uint256 tokens) returns(bool success)
func (_Eth *EthTransactorSession) TransferFrom(from common.Address, to common.Address, tokens *big.Int) (*types.Transaction, error) {
return _Eth.Contract.TransferFrom(&_Eth.TransactOpts, from, to, tokens)
}

// EthApprovalIterator is returned from FilterApproval and is used to iterate over the raw logs and unpacked data for Approval events raised by the Eth contract.
type EthApprovalIterator struct {
Event *EthApproval // Event containing the contract specifics and raw log

contract *bind.BoundContract // Generic contract to use for unpacking event data
event string // Event name to use for unpacking event data

logs chan types.Log // Log channel receiving the found contract events
sub ethereum.Subscription // Subscription for errors, completion and termination
done bool // Whether the subscription completed delivering logs
fail error // Occurred error to stop iteration
}

// Next advances the iterator to the subsequent event, returning whether there
// are any more events found. In case of a retrieval or parsing error, false is
// returned and Error() can be queried for the exact failure.
func (it *EthApprovalIterator) Next() bool {
// If the iterator failed, stop iterating
if it.fail != nil {
return false
}
// If the iterator completed, deliver directly whatever's available
if it.done {
select {
case log := <-it.logs:
it.Event = new(EthApproval)
if err := it.contract.UnpackLog(it.Event, it.event, log); err != nil {
it.fail = err
return false
}
it.Event.Raw = log
return true

default:
return false
}
}
// Iterator still in progress, wait for either a data or an error event
select {
case log := <-it.logs:
it.Event = new(EthApproval)
if err := it.contract.UnpackLog(it.Event, it.event, log); err != nil {
it.fail = err
return false
}
it.Event.Raw = log
return true

case err := <-it.sub.Err():
it.done = true
it.fail = err
return it.Next()
}
}

// Error returns any retrieval or parsing error occurred during filtering.
func (it *EthApprovalIterator) Error() error {
return it.fail
}

// Close terminates the iteration process, releasing any pending underlying
// resources.
func (it *EthApprovalIterator) Close() error {
it.sub.Unsubscribe()
return nil
}

// EthApproval represents a Approval event raised by the Eth contract.
type EthApproval struct {
TokenOwner common.Address
Spender common.Address
Tokens *big.Int
Raw types.Log // Blockchain specific contextual infos
}

// FilterApproval is a free log retrieval operation binding the contract event 0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925.
//
// Solidity: event Approval(address indexed tokenOwner, address indexed spender, uint256 tokens)
func (_Eth *EthFilterer) FilterApproval(opts *bind.FilterOpts, tokenOwner []common.Address, spender []common.Address) (*EthApprovalIterator, error) {

var tokenOwnerRule []interface{}
for _, tokenOwnerItem := range tokenOwner {
tokenOwnerRule = append(tokenOwnerRule, tokenOwnerItem)
}
var spenderRule []interface{}
for _, spenderItem := range spender {
spenderRule = append(spenderRule, spenderItem)
}

logs, sub, err := _Eth.contract.FilterLogs(opts, "Approval", tokenOwnerRule, spenderRule)
if err != nil {
return nil, err
}
return &EthApprovalIterator{contract: _Eth.contract, event: "Approval", logs: logs, sub: sub}, nil
}

// WatchApproval is a free log subscription operation binding the contract event 0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925.
//
// Solidity: event Approval(address indexed tokenOwner, address indexed spender, uint256 tokens)
func (_Eth *EthFilterer) WatchApproval(opts *bind.WatchOpts, sink chan<- *EthApproval, tokenOwner []common.Address, spender []common.Address) (event.Subscription, error) {

var tokenOwnerRule []interface{}
for _, tokenOwnerItem := range tokenOwner {
tokenOwnerRule = append(tokenOwnerRule, tokenOwnerItem)
}
var spenderRule []interface{}
for _, spenderItem := range spender {
spenderRule = append(spenderRule, spenderItem)
}

logs, sub, err := _Eth.contract.WatchLogs(opts, "Approval", tokenOwnerRule, spenderRule)
if err != nil {
return nil, err
}
return event.NewSubscription(func(quit <-chan struct{}) error {
defer sub.Unsubscribe()
for {
select {
case log := <-logs:
// New log arrived, parse the event and forward to the user
event := new(EthApproval)
if err := _Eth.contract.UnpackLog(event, "Approval", log); err != nil {
return err
}
event.Raw = log

select {
case sink <- event:
case err := <-sub.Err():
return err
case <-quit:
return nil
}
case err := <-sub.Err():
return err
case <-quit:
return nil
}
}
}), nil
}

// ParseApproval is a log parse operation binding the contract event 0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925.
//
// Solidity: event Approval(address indexed tokenOwner, address indexed spender, uint256 tokens)
func (_Eth *EthFilterer) ParseApproval(log types.Log) (*EthApproval, error) {
event := new(EthApproval)
if err := _Eth.contract.UnpackLog(event, "Approval", log); err != nil {
return nil, err
}
return event, nil
}

// EthTransferIterator is returned from FilterTransfer and is used to iterate over the raw logs and unpacked data for Transfer events raised by the Eth contract.
type EthTransferIterator struct {
Event *EthTransfer // Event containing the contract specifics and raw log

contract *bind.BoundContract // Generic contract to use for unpacking event data
event string // Event name to use for unpacking event data

logs chan types.Log // Log channel receiving the found contract events
sub ethereum.Subscription // Subscription for errors, completion and termination
done bool // Whether the subscription completed delivering logs
fail error // Occurred error to stop iteration
}

// Next advances the iterator to the subsequent event, returning whether there
// are any more events found. In case of a retrieval or parsing error, false is
// returned and Error() can be queried for the exact failure.
func (it *EthTransferIterator) Next() bool {
// If the iterator failed, stop iterating
if it.fail != nil {
return false
}
// If the iterator completed, deliver directly whatever's available
if it.done {
select {
case log := <-it.logs:
it.Event = new(EthTransfer)
if err := it.contract.UnpackLog(it.Event, it.event, log); err != nil {
it.fail = err
return false
}
it.Event.Raw = log
return true

default:
return false
}
}
// Iterator still in progress, wait for either a data or an error event
select {
case log := <-it.logs:
it.Event = new(EthTransfer)
if err := it.contract.UnpackLog(it.Event, it.event, log); err != nil {
it.fail = err
return false
}
it.Event.Raw = log
return true

case err := <-it.sub.Err():
it.done = true
it.fail = err
return it.Next()
}
}

// Error returns any retrieval or parsing error occurred during filtering.
func (it *EthTransferIterator) Error() error {
return it.fail
}

// Close terminates the iteration process, releasing any pending underlying
// resources.
func (it *EthTransferIterator) Close() error {
it.sub.Unsubscribe()
return nil
}

// EthTransfer represents a Transfer event raised by the Eth contract.
type EthTransfer struct {
From common.Address
To common.Address
Tokens *big.Int
Raw types.Log // Blockchain specific contextual infos
}

// FilterTransfer is a free log retrieval operation binding the contract event 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef.
//
// Solidity: event Transfer(address indexed from, address indexed to, uint256 tokens)
func (_Eth *EthFilterer) FilterTransfer(opts *bind.FilterOpts, from []common.Address, to []common.Address) (*EthTransferIterator, error) {

var fromRule []interface{}
for _, fromItem := range from {
fromRule = append(fromRule, fromItem)
}
var toRule []interface{}
for _, toItem := range to {
toRule = append(toRule, toItem)
}

logs, sub, err := _Eth.contract.FilterLogs(opts, "Transfer", fromRule, toRule)
if err != nil {
return nil, err
}
return &EthTransferIterator{contract: _Eth.contract, event: "Transfer", logs: logs, sub: sub}, nil
}

// WatchTransfer is a free log subscription operation binding the contract event 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef.
//
// Solidity: event Transfer(address indexed from, address indexed to, uint256 tokens)
func (_Eth *EthFilterer) WatchTransfer(opts *bind.WatchOpts, sink chan<- *EthTransfer, from []common.Address, to []common.Address) (event.Subscription, error) {

var fromRule []interface{}
for _, fromItem := range from {
fromRule = append(fromRule, fromItem)
}
var toRule []interface{}
for _, toItem := range to {
toRule = append(toRule, toItem)
}

logs, sub, err := _Eth.contract.WatchLogs(opts, "Transfer", fromRule, toRule)
if err != nil {
return nil, err
}
return event.NewSubscription(func(quit <-chan struct{}) error {
defer sub.Unsubscribe()
for {
select {
case log := <-logs:
// New log arrived, parse the event and forward to the user
event := new(EthTransfer)
if err := _Eth.contract.UnpackLog(event, "Transfer", log); err != nil {
return err
}
event.Raw = log

select {
case sink <- event:
case err := <-sub.Err():
return err
case <-quit:
return nil
}
case err := <-sub.Err():
return err
case <-quit:
return nil
}
}
}), nil
}

// ParseTransfer is a log parse operation binding the contract event 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef.
//
// Solidity: event Transfer(address indexed from, address indexed to, uint256 tokens)
func (_Eth *EthFilterer) ParseTransfer(log types.Log) (*EthTransfer, error) {
event := new(EthTransfer)
if err := _Eth.contract.UnpackLog(event, "Transfer", log); err != nil {
return nil, err
}
return event, nil
}

这个go的源码看一下就可以发现,abi是怎么打包和解包数据的。

通过RPC接口获取log

log数据格式

eth_getLogs接口信息

1
2
3
4
5
6
7
8
9
10
11
eth_getLogs

返回符合过滤条件的log数组
参数信息

对象 - 过滤选项:

fromBlock: 起始block num.
toBlock: 结束block num.
address: 合约地址或者合约地址数组.
topics: 数组,元素为 event name的id, index 的参数, 对应上文图片中的topic.

这个接口对应的ethclient的函数名叫FilterLogs

1
2
3
4
5
6
7
8
9
10
// FilterLogs executes a filter query.
func (ec *Client) FilterLogs(ctx context.Context, q ethereum.FilterQuery) ([]types.Log, error) {
var result []types.Log
arg, err := toFilterArg(q)
if err != nil {
return nil, err
}
err = ec.c.CallContext(ctx, &result, "eth_getLogs", arg)
return result, err
}

检测erc20交易

有了以上的信息,把这些功能组合起来就可以实现erc20的交易检测了。这个逻辑我们用时序图表示:

主要功能代码是

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
type LogTransfer struct {
From string
To string
Tokens *big.Int
}
contractAbi, err := abi.JSON(strings.NewReader(EthABI))
if err != nil {
hcommon.Log.Warnf("err: [%T] %s", err, err.Error())
return
}
var transferEvent LogTransfer
err := contractAbi.Unpack(&transferEvent, "Transfer", log.Data)
if err != nil {
hcommon.Log.Warnf("err: [%T] %s", err, err.Error())
return
}
transferEvent.From = strings.ToLower(common.HexToAddress(log.Topics[1].Hex()).Hex())
transferEvent.To = strings.ToLower(common.HexToAddress(log.Topics[2].Hex()).Hex())
contractAddress := strings.ToLower(log.Address.Hex())

检测数据库交易,并添加发送通知数据表

添加发送数据通知和以太坊(eth)交易所钱包开发 - 7 - 冲币提币回调处理逻辑是一样的,只不过需要处理不同的数据表而已。

整合代码

具体实现的代码已经传到了github https://github.com/moremorefun/go-dc-wallet

功能入口在

  • cmd/erc20_block_seek/main.go
  • cmd/erc20_tx_notify/main.go

坚持原创技术分享,您的支持鼓励我继续创作!