ERC-721 Caighdeán Comhartha Neamh-idirmhalartach

Réamhrá

Cad is Comhartha Neamh-idirmhalartach ann?

Baintear úsáid as Comhartha Neamh-idirmhalartach (NFT) chun rud nó duine éigin a aithint ar bhealach uathúil. Tá an cineál seo Comhartha foirfe le húsáid ar ardáin a thairgeann míreanna inbhailithe, eochracha rochtana, ticéid chrannchuir, suíocháin uimhrithe do cheolchoirmeacha agus cluichí spóirt, srl. Tá féidearthachtaí iontacha ag an gcineál speisialta Comhartha seo agus mar sin tá Caighdeán ceart, ERC-721, a tháinig chun é sin a réiteach, tuillte aige!

Cad é ERC-721?

Tugann an ERC-721 isteach caighdeán do NFT, i bhfocail eile, tá an cineál Comhartha seo uathúil agus is féidir luach difriúil a bheith aige ó Chomhartha eile ón gConradh Cliste céanna, b'fhéidir mar gheall ar a aois, a theirce nó fiú rud éigin eile cosúil lena amharc. Fan, amharc?

Sin é! Tá athróg uint256 ag gach NFT ar a dtugtar tokenId, mar sin d'aon Chonradh ERC-721, ní mór an péire contract address, uint256 tokenId a bheith uathúil ar fud an domhain. Mar sin féin, is féidir "tiontaire" a bheith ag dapp a úsáideann an tokenId mar ionchur agus a aschuireann íomhá de rud éigin faiseanta, cosúil le zombaithe, airm, scileanna nó puisíní gleoite!

Réamhriachtanais

Comhlacht

An ERC-721 (Iarratas Ethereum ar Thuairimí 721), molta ag William Entriken, Dieter Shirley, Jacob Evans, Tá Nastassia Sachs i mí Eanáir 2018, ina Chaighdeán Comhartha Neamh-idirmhalartacha a chuireann API le haghaidh comharthaí laistigh de Chonarthaí Cliste i bhfeidhm.

Soláthraíonn sé feidhmiúlachtaí cosúil le comharthaí a aistriú ó chuntas amháin go cuntas eile, chun an iarmhéid reatha chomharthaí a fháil ar chuntas, chun úinéir chomhartha sainiúil a aimsiú agus freisin soláthar iomlán an chomhartha atá ar fáil ar an líonra. Chomh maith leo seo tá roinnt feidhmiúlachtaí eile aige ar nós an méid de chomhartha is féidir le cuntas tríú pháirtí a bhogadh ó chuntas a fhaomhadh.

Má chuireann Conradh Cliste na modhanna agus na teagmhais seo a leanas i bhfeidhm is féidir Conradh Comhartha Neamh-idirmhalartach ERC-721 a thabhairt air agus, ar é a imscaradh, beidh sé freagrach as súil a choinneáil ar na comharthaí cruthaithe ar Ethereum.

Ó EIP-721opens in a new tab:

Modhanna

1    function balanceOf(address _owner) external view returns (uint256);
2    function ownerOf(uint256 _tokenId) external view returns (address);
3    function safeTransferFrom(address _from, address _to, uint256 _tokenId, bytes data) external payable;
4    function safeTransferFrom(address _from, address _to, uint256 _tokenId) external payable;
5    function transferFrom(address _from, address _to, uint256 _tokenId) external payable;
6    function approve(address _approved, uint256 _tokenId) external payable;
7    function setApprovalForAll(address _operator, bool _approved) external;
8    function getApproved(uint256 _tokenId) external view returns (address);
9    function isApprovedForAll(address _owner, address _operator) external view returns (bool);
Taispeáin gach rud

Imeachtaí

1    event Transfer(address indexed _from, address indexed _to, uint256 indexed _tokenId);
2    event Approval(address indexed _owner, address indexed _approved, uint256 indexed _tokenId);
3    event ApprovalForAll(address indexed _owner, address indexed _operator, bool _approved);

Samplaí

Feicimis conas atá Caighdeán chomh tábhachtach chun go mbeadh sé simplí dúinn iniúchadh a dhéanamh ar aon Chonradh Chomhartha ERC-721 ar Ethereum. Níl uainn ach Comhéadan Dénártha Feidhmchláir Conartha (ABI) chun comhéadan a chruthú d’aon Chomhartha ERC-721. Mar atá le feiceáil thíos bainfimid úsáid as ABI simplithe, chun sampla frithchuimilte íseal a dhéanamh de.

Sampla Web3.py

Ar dtús, déan cinnte go bhfuil Web3.pyopens in a new tab leabharlann Python suiteáilte agat:

1pip install web3

1from web3 import Web3
2from web3._utils.events import get_event_data
3
4
5w3 = Web3(Web3.HTTPProvider("https://cloudflare-eth.com"))
6
7ck_token_addr = "0x06012c8cf97BEaD5deAe237070F9587f8E7A266d"    # CryptoKitties Contract
8
9acc_address = "0xb1690C08E213a35Ed9bAb7B318DE14420FB57d8C"      # CryptoKitties Sales Auction
10
11# This is a simplified Contract Application Binary Interface (ABI) of an ERC-721 NFT Contract.
12# It will expose only the methods: balanceOf(address), name(), ownerOf(tokenId), symbol(), totalSupply()
13simplified_abi = [
14    {
15        'inputs': [{'internalType': 'address', 'name': 'owner', 'type': 'address'}],
16        'name': 'balanceOf',
17        'outputs': [{'internalType': 'uint256', 'name': '', 'type': 'uint256'}],
18        'payable': False, 'stateMutability': 'view', 'type': 'function', 'constant': True
19    },
20    {
21        'inputs': [],
22        'name': 'name',
23        'outputs': [{'internalType': 'string', 'name': '', 'type': 'string'}],
24        'stateMutability': 'view', 'type': 'function', 'constant': True
25    },
26    {
27        'inputs': [{'internalType': 'uint256', 'name': 'tokenId', 'type': 'uint256'}],
28        'name': 'ownerOf',
29        'outputs': [{'internalType': 'address', 'name': '', 'type': 'address'}],
30        'payable': False, 'stateMutability': 'view', 'type': 'function', 'constant': True
31    },
32    {
33        'inputs': [],
34        'name': 'symbol',
35        'outputs': [{'internalType': 'string', 'name': '', 'type': 'string'}],
36        'stateMutability': 'view', 'type': 'function', 'constant': True
37    },
38    {
39        'inputs': [],
40        'name': 'totalSupply',
41        'outputs': [{'internalType': 'uint256', 'name': '', 'type': 'uint256'}],
42        'stateMutability': 'view', 'type': 'function', 'constant': True
43    },
44]
45
46ck_extra_abi = [
47    {
48        'inputs': [],
49        'name': 'pregnantKitties',
50        'outputs': [{'name': '', 'type': 'uint256'}],
51        'payable': False, 'stateMutability': 'view', 'type': 'function', 'constant': True
52    },
53    {
54        'inputs': [{'name': '_kittyId', 'type': 'uint256'}],
55        'name': 'isPregnant',
56        'outputs': [{'name': '', 'type': 'bool'}],
57        'payable': False, 'stateMutability': 'view', 'type': 'function', 'constant': True
58    }
59]
60
61ck_contract = w3.eth.contract(address=w3.to_checksum_address(ck_token_addr), abi=simplified_abi+ck_extra_abi)
62name = ck_contract.functions.name().call()
63symbol = ck_contract.functions.symbol().call()
64kitties_auctions = ck_contract.functions.balanceOf(acc_address).call()
65print(f"{name} [{symbol}] NFTs in Auctions: {kitties_auctions}")
66
67pregnant_kitties = ck_contract.functions.pregnantKitties().call()
68print(f"{name} [{symbol}] NFTs Pregnants: {pregnant_kitties}")
69
70# Using the Transfer Event ABI to get info about transferred Kitties.
71tx_event_abi = {
72    'anonymous': False,
73    'inputs': [
74        {'indexed': False, 'name': 'from', 'type': 'address'},
75        {'indexed': False, 'name': 'to', 'type': 'address'},
76        {'indexed': False, 'name': 'tokenId', 'type': 'uint256'}],
77    'name': 'Transfer',
78    'type': 'event'
79}
80
81# We need the event's signature to filter the logs
82event_signature = w3.keccak(text="Transfer(address,address,uint256)").hex()
83
84logs = w3.eth.get_logs({
85    "fromBlock": w3.eth.block_number - 120,
86    "address": w3.to_checksum_address(ck_token_addr),
87    "topics": [event_signature]
88})
89
90# Notes:
91#   - Increase the number of blocks up from 120 if no Transfer event is returned.
92#   - If you didn't find any Transfer event you can also try to get a tokenId at:
93#       https://etherscan.io/address/0x06012c8cf97BEaD5deAe237070F9587f8E7A266d#events
94#       Click to expand the event's logs and copy its "tokenId" argument
95recent_tx = [get_event_data(w3.codec, tx_event_abi, log)["args"] for log in logs]
96
97if recent_tx:
98    kitty_id = recent_tx[0]['tokenId'] # Paste the "tokenId" here from the link above
99    is_pregnant = ck_contract.functions.isPregnant(kitty_id).call()
100    print(f"{name} [{symbol}] NFTs {kitty_id} is pregnant: {is_pregnant}")
Taispeáin gach rud

Tá roinnt Imeachtaí suimiúla ag CryptoKitties Contract seachas na cinn Caighdeánacha.

Déanaimis seiceáil ar dhá cheann acu, Toirchis agus Breith.

1# Using the Pregnant and Birth Events ABI to get info about new Kitties.
2ck_extra_events_abi = [
3    {
4        'anonymous': False,
5        'inputs': [
6            {'indexed': False, 'name': 'owner', 'type': 'address'},
7            {'indexed': False, 'name': 'matronId', 'type': 'uint256'},
8            {'indexed': False, 'name': 'sireId', 'type': 'uint256'},
9            {'indexed': False, 'name': 'cooldownEndBlock', 'type': 'uint256'}],
10        'name': 'Pregnant',
11        'type': 'event'
12    },
13    {
14        'anonymous': False,
15        'inputs': [
16            {'indexed': False, 'name': 'owner', 'type': 'address'},
17            {'indexed': False, 'name': 'kittyId', 'type': 'uint256'},
18            {'indexed': False, 'name': 'matronId', 'type': 'uint256'},
19            {'indexed': False, 'name': 'sireId', 'type': 'uint256'},
20            {'indexed': False, 'name': 'genes', 'type': 'uint256'}],
21        'name': 'Birth',
22        'type': 'event'
23    }]
24
25# We need the event's signature to filter the logs
26ck_event_signatures = [
27    w3.keccak(text="Pregnant(address,uint256,uint256,uint256)").hex(),
28    w3.keccak(text="Birth(address,uint256,uint256,uint256,uint256)").hex(),
29]
30
31# Here is a Pregnant Event:
32# - https://etherscan.io/tx/0xc97eb514a41004acc447ac9d0d6a27ea6da305ac8b877dff37e49db42e1f8cef#eventlog
33pregnant_logs = w3.eth.get_logs({
34    "fromBlock": w3.eth.block_number - 120,
35    "address": w3.to_checksum_address(ck_token_addr),
36    "topics": [ck_event_signatures[0]]
37})
38
39recent_pregnants = [get_event_data(w3.codec, ck_extra_events_abi[0], log)["args"] for log in pregnant_logs]
40
41# Here is a Birth Event:
42# - https://etherscan.io/tx/0x3978028e08a25bb4c44f7877eb3573b9644309c044bf087e335397f16356340a
43birth_logs = w3.eth.get_logs({
44    "fromBlock": w3.eth.block_number - 120,
45    "address": w3.to_checksum_address(ck_token_addr),
46    "topics": [ck_event_signatures[1]]
47})
48
49recent_births = [get_event_data(w3.codec, ck_extra_events_abi[1], log)["args"] for log in birth_logs]
Taispeáin gach rud

NFTanna Coitianta

Liostaíonn Etherscan NFT Trackeropens in a new tab an NFT is fearr ar Ethereum de réir méid aistrithe.
Is cluiche é CryptoKittiesopens in a new tab atá dírithe ar neacha inphóraithe, inbhailithe aoibhne a dtugtar CryptoKitties orthu.
Is cluiche peile fantaisíochta domhanda é Sorareopens in a new tab inar féidir leat eagráin teoranta nithe inbhailithe a bhailiú, do chuid foirne a bhainistiú agus dul san iomaíocht chun duaiseanna a thuilleamh.
Soláthraíonn Seirbhís Ainmneacha Ethereum (ENS)opens in a new tab bealach díláraithe slán & chun aghaidh a thabhairt ar acmhainní ar an mblocshlabhra agus as, ag baint úsáide as ainmneacha simplí atá inléite ag an duine.
Seachadann POAPopens in a new tab NFTanna saor in aisce do dhaoine a fhreastalaíonn ar imeachtaí nó a dhéanann gníomhartha sonracha. Is féidir POAPanna a chruthú agus a dháileadh.
Is cuideachta atá lonnaithe i San Francisco é Unstoppable Domainsopens in a new tab a thógann fearainn ar blocshlabhra. Cuireann fearainn Bhlocshlabhra ainmneacha inléite daonna in ionad seoltaí criptea-airgeadra agus is féidir iad a úsáid chun a chumasú láithreáin ghréasáin atá díonach ar chinsireacht.
Is TCG é Gods Unchained Cardsopens in a new tab ar bhlocshlabhra Ethereum a úsáideann NFTanna chun fíor-úinéireacht a thabhairt chuig sócmhainní in-chluiche.
Is bailiúchán é Bored Ape Yacht Clubopens in a new tab bailiúchán de 10,000 NFT uathúla, a fheidhmíonn, chomh maith le bheith ina phíosa ealaíne annamh, mar chomhartha ballraíochta don chlub, ag soláthar buntáistí agus tairbhí do chomhaltaí a mhéadaíonn le himeacht ama mar thoradh ar iarrachtaí pobail.