実践ブロックチェーンゲーム/Blockchain Game in Practice

2018-12-17 blockchain.tokyo #15
https://blockchain-tokyo.connpass.com/event/110424/

Transcript

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2. ࣮ફϒϩοΫνΣʔϯήʔϜ
   2018-12-17 blockchain.tokyo#15
   @rmanzoku
   

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3. ࣗݾ঺հ
   Name: Ryo Manzoku
   @rmanzoku
   Work: double jump.tokyo inc
   Job: Blockchain Engineer
   Sidework: 

   SRE / Cloud Infrastructure
   Language:

   Golang / Python
   

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4. https://mch.gg/
   

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5. My Crypto Heroes֓ཁ
   My Crypto HeroesɺMCHɺϚΠΫϦ
   2018-11-30 ਖ਼ࣜαʔϏε։࢝
   EthereumΛར༻ͨ͠ϒϩοΫνΣʔϯήʔϜ
   ϫʔΧʔϓϨΠεϝϯτܕRPG
   Ξηοτ(ERC721)͸Ethereum mainnet ʹͯ؅ཧ
   ήʔϜϩδοΫ͸ΦϑνΣʔϯαʔόʹ࣮ͯߦ
   PCͰ΋εϚϗͰ΋ɺWallet͕ͳͯ͘΋༡΂Δ
   

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6. My Crypto Heroes֓ཁ
   ήʔϜʹ͔͚ͨ࣌ؒ΋͓ۚ΋৘೤΋ɺ

   ͋ͳͨͷࢿ࢈ͱͳΔੈք
   Ethereumʹ͋ΔAsset͸Ϣʔβʔ͕ࣗ༝ʹѻ͏͜ͱ͕Ͱ͖Δ
   AssetΛҭ੒͢Δ͜ͱͰࢿ࢈ͱͯ͠ͷՁ஋ΛߴΊΔ͜ͱ͕Մೳ
   Assetͱͯ͠ύʔςΟʹฤ੒Ͱ͖ΔHeroͱHero͕૷උ͢Δ
   Extensionͷ2͕ͭ͋Δʢ2018/12/16࣌఺ʣ
   Asset͸Smart ContractʹΑͬͯൃߦ্ݶ͕ఆΊΒΕ͍ͯΔ
   

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7. ࠓ೔࿩͢͜ͱ
   HiCon2018Ͱൃදͨ͠಺༰ͷิ଍
   MCHͰՔಇ͍ͯ͠ΔSmart Contractͷղઆ
   ࠓ೔ͷEthereumͰɺήʔϜͷΑ͏ͳෳࡶͳϩδοΫΛ࣮૷͢Δͷ͸
   ෆՄೳ
   ͱ͸͍͑αʔϏεΛੈͷதʹग़͞Ͷ͹࢝·Βͳ͍
   EthereumͷੈքͱήʔϜͷੈքΛܨ͙ٕज़
   Թ౓ײ͕Θ͔Βͳ͔ͬͨͷͰط஌ͷ৘ใ͹͔ΓͩͬͨΒ͢Έ·ͤΜ
   

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8. ٕज़എܠ
   AssetΛΦϯνΣʔϯɺήʔϜ͸ΦϑνΣʔϯͱͯ͠اըʢ4݄ʣ
   Etheremonͷॿݴ΋͋ΓΦϯνΣʔϯʢEVMʣͰͷ࣮૷΁ํ਑స
   ׵ʢ6݄ʣ
   ʢࢲ͕δϣΠϯʣ
   Loom NetworkΛ࢖ͬͨότϧβΛ࣮ࢪɺݱ࣌఺ͰͷΦϯνΣʔϯ
   ࣮૷Λஅ೦ʢ10݄ʣ
   େ෦෼ΛΦϑνΣʔϯԽʢ11݄ʣ
   

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9. HiCon2018Ͱͷൃද
   https://mch.gg/hicon2018
   

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10. HiCon2018Ͱͷൃද
    https://mch.gg/hicon2018
    

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11. EVM on Loom SDK
    Loom݁ߏ଎͍
    ϒϩοΫੜ੒଎౓͸1ඵ
    ͔͠͠ότϧॲཧʹ10ඵҎ্͔͔Δ
    ͦͷؒɺWrite͸͢΂ͯϒϩοΫ
    Read΋Կނ͔ॏ͍
    

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12. HiCon2018Ͱͷൃද
    https://mch.gg/hicon2018
    

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13. Eventϩʔυόϥϯαʔ
    Master LoomͷEventΛGoरͬͯɺSlave LoomʹॲཧΛ
    ྲྀ͢όον͕ಈ͍͍ͯΔ
    ൃ૝ͱͯ͠͸State-channelʹ͍ۙ͸ͣ
    ࣄ্࣮ͷϩʔυόϥϯαʔ
    ʢͦ΋ͦ΋Master/Slaveͬͯɺɺɺʣ
    EventΛरͬͯॲཧ͢ΔͷͰΤϯυΤϯυͩͱ਺ඵ͔͔
    Δ͕ϒϩοΫ͸ͳ͘ͳΔ
    

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14. SidechainͰͷݶք
    ͦ΋ͦ΋ϒϩοΫνΣʔϯͰ͋ΔҎ্ɺγϦΞϧॲ
    ཧͰ͔࣮͠ߦͰ͖ͳ͍
    CPUར༻ޮ཰͸ѱ͍
    ࢖͍͍͑ͯͤͥ3ίΞఔ౓
    ότϧͷϩάΛు͖͗ͯ͢1ϲ݄Ͱ100GB͘Β͍σΟ
    εΫΛ৯͏
    ͜ͷ࣌ظɺேཁܾ݅·ͬͯ༦ํʹ͸৽نαʔόʹσ
    ϓϩΠΈ͍ͨͳঢ়گͩͬͨ
    

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15. HiCon2018Ͱͷൃද
    https://mch.gg/hicon2018
    

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16. HiCon2018Ͱͷൃද
    https://mch.gg/hicon2018
    

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19. MCHͷήʔϜੑ
    HeroΛETHͳͲͰखʹೖΕɺΫΤετʹ޲͔͍ใुͰ͋
    ΔExtensionΛऩू
    Hero΍ExtensionͷϨϕϧΛ্͛ߴ೉қ౓ͷΫΤετ΁
    ௅ઓ
    खʹೖΕͨHeroɺExtensionΛήʔϜ಺औҾॴͰചങ
    ॴ༗͢ΔHeroɺExtensionΛEthereum্΁సૹ
    

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20. Main chainͰ؅ཧ͢Δ΋ͷ
    Hero/Extension Assetॴ༗ݖ
    Hero/Extension Assetൃߦ্ݶ
    Hero/ExtensionΛήʔϜ಺Ͱར༻͢ΔͨΊͷGateway
    

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21. Smart contractʹ͍ͭͯ
    Ethereum্ͰϩδοΫΛಈ͔ͨ͢ΊͷϓϩάϥϜ
    MCHͰ͸ಁ໌ੑ֬อͷͨΊEtherscanͰެ։
    https://mch.gg/etherscan
    ࠓޙOSS΍Ұ෦ϩδοΫʹ͍ͭͯ͸ϥΠηϯεܖ໿
    ͷݩɺଞࣾͰ΋ར༻Ͱ͖ΔΑ͏ʹ੔උ༧ఆ
    MCH͸ۀքൃలͷͨΊੵۃతʹٕज़Λ৘ใެ։
    

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22. ERC 721ͱ͸
    Ethereumͷඪ४ن֨ͷҰͭͰNon-Fungible TokenʢNFTʣΛنఆ
    ͨ͠ΠϯλʔϑΣʔε
    NFTͱ͸ɺ୅ସෆՄೳͳ΋ͷ
    CryptoKittiesΛൃ୺ʹEthereum্ͰToken/Assetͷॴ༗ݖͳͲΛن
    ఆ
    ࢀর࣮૷ͱͯ͠OpenZeppelinOSͷ΋ͷ͕༗໊
    CryptoZombies΋ERC721
    ERC20ͱൺֱ͞ΕΔ
    

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23. Assetॴ༗ݖ
    ERC 721 NFT
    ͩΕ͕͜ͷAssetΛॴ༗͍ͯ͠Δ͔
    AssetΛੜΈग़͢Mint΍ॴ༗ݖΛҠৡ͢ΔTransferͳ
    Ͳ
    OpenZeppelin 2.0 RC1Λܧঝ
    Hero/Extensionͱ΋ʹERC721
    

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24. Assetൃߦ্ݶ
    ERC 721ʹ௥Ճ࣮૷
    ৽Hero΍৽Extension࣮૷࣌ʹࣄલʹൃߦ਺Ληοτ
    Mint࣌ʹൃߦ਺νΣοΫ
    Type͝ͱʹೳྗ͕͋ΓɺͦͷTypeͷൃߦ্ݶ͕ܾ·͍ͬͯΔ
    CryptoKittiesͳͲͱҧ͍ɺID͔Βೳྗ͕ܾఆ͢ΔΘ͚Ͱ͸ͳ͍
    ΋ͪΖΜՁ஋ͷߴ͍΋ͷ΄Ͳൃߦ਺͕গͳ͍
    ৫ా৴௕͸ੈքʹ10ମ͔͠ੜ·Ε·ͤΜʂΛContractͰอূ
    

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25. Assetൃߦ্ݶ
    mapping(uint16 => uint16) private extensionTypeToSupplyLimit;
    function setSupplyLimit(uint16 _extensionType, uint16 _supplyLimit)
    external onlyMinter {
    require(_supplyLimit != 0);
    require(extensionTypeToSupplyLimit[_extensionType] == 0 ||
    _supplyLimit < extensionTypeToSupplyLimit[_extensionType],
    "_supplyLimit is bigger”);
    extensionTypeToSupplyLimit[_extensionType] = _supplyLimit;
    }
    function mintExtensionAsset(address _owner, uint256 _tokenId)
    public onlyMinter {
    uint16 _extensionType = uint16(_tokenId / EXTENSION_TYPE_OFFSET);
    uint16 _extensionTypeIndex = uint16(_tokenId % EXTENSION_TYPE_OFFSET) - 1;
    require(_extensionTypeIndex < extensionTypeToSupplyLimit[_extensionType],
    "supply over");
    _mint(_owner, _tokenId);
    }
    

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26. Asset Gateway
    ήʔϜ಺ͰAssetͷऔҾ͕ߦ͑ΔͨΊɺήʔϜ಺Ͱѻ͍ͬͯ
    ΔAssetʹసૹͳͲߦ͑ͳ͍Α͏ϩοΫ͢Δඞཁ͕͋Δɻ
    Gateway contract͕͋ΓɺͦͷContractʹAssetΛTransfer
    ͢Δ͜ͱͰ࣮ݱ
    Deposit / Withdrawͱ࣮ͯ͠૷
    OpenZeppelinOSͰɺContract͕ड͚औΔ৔߹
    ERC721Receiver͕نఆ͞Ε͍ͯΔͷͰै͏ͱྑ͍
    

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27. ͦ΋ͦ΋ͳͥGateway͔
    Ethereum্Ͱ͢΂ͯͷϩδοΫΛ࣮૷͢ΔͱGasͳͲͷϢʔ
    βʔίετ͕͔͔ΔɺUXతʹਏ͍
    PlasmaΛච಄ʹεέʔϦϯάٕज़͸ߟҊ͞Ε͍ͯΔ΋ͷͷ
    ࣮Քಇ͍ͯ͠Δ΋ͷ͸΄΅ͳ͍
    ϝΠϯνΣʔϯͱʮεέʔϦϯάٕज़XʯΛܨ͙ٕज़͕ඞཁ
    Xʹ͸޷͖ͳݴ༿ΛೖΕΑ͏
    MCHͰ͸ΦϑνΣʔϯ
    

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28. ܨ͙ٕज़
    ContractͷEventΛ࢖͏
    GatewayʹAsset͕Transfer͞Εͨͱ͍͏EventΛ؂ࢹ
    EventΛΫϩʔϧ͠ɺΦϑνΣʔϯͷgRPCΛ࣮ߦ͢Δ
    औΓ͜΅͕͠ා͍ͷͰఆظ࣮ߦ͢Δ
    TxHashΛ࢖ͬͯႈ౳ੑΛอূ͢Δ
    

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29. ͭ·ΓͨͩͷBatch
    

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30. abigen
    Solidityͷίʔυ͔ΒGolangΫϥΠΞϯτίʔυΛࣗ
    ಈੜ੒ͯ͘͠ΕΔίϚϯυ
    https://github.com/ethereum/go-ethereum/wiki/
    Native-DApps:-Go-bindings-to-Ethereum-contracts
    Event subscription͕·ͩ࢖͑ͳ͍ͦ͏Ͱ͕͢ɺόο
    ν༻్ʹ͸े෼࢖͑Δ
    

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31. $ abigen --abi token.abi -pkg main -type Token -out token.go
    package main
    import (
    "fmt"
    “log"
    “token”
    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/ethclient"
    )
    func main() {
    // Create an IPC based RPC connection to a remote node
    conn, err := ethclient.Dial("/home/karalabe/.ethereum/testnet/geth.ipc")
    if err != nil {
    log.Fatalf("Failed to connect to the Ethereum client: %v", err)
    }
    // Instantiate the contract and display its name
    token, err := NewToken(common.HexToAddress("0x21e6fc92f93c8a1bb41e2be64b4e1f88a54d3576"), conn)
    if err != nil {
    log.Fatalf("Failed to instantiate a Token contract: %v", err)
    }
    name, err := token.Name(nil)
    if err != nil {
    log.Fatalf("Failed to retrieve token name: %v", err)
    }
    fmt.Println("Token name:", name)
    }
    

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32. abigenΊͬͪΌศར
    ͦ΋ͦ΋Solidity/web3͸abi͔Βࢉग़Ͱ͖ΔόΠτίʔυΛ
    ΍ΓͱΓ͢ΔͷͰͦͷղऍΛ͢Δඞཁ͕͋Δ
    ϒϥ΢βͷ৔߹͸web3.jsΛ࢖͏
    ͍ͭϝδϟʔόʔδϣϯ͕͋ΔΜͰ͠ΐ͏Ͷɺɺ
    αʔόͷ৔߹͸ɺNodeJSΛ࢖͏͔ɺabigenͨ͠GoΛ࢖͏ͷ
    ͕ݱঢ়ͷબ୒ࢶͰ͸
    ༨ஊͰ͕͢ɺethereum/go-ethereumϦϙδτϦ͸͔ͳΓಡ
    ΈࠐΉ͜ͱʹͳΔʢυΩϡϝϯτ͸͋·Γͳ͍ʣ
    

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33. op, _ := crawler.GetCommandOptions()
    c, err := crawler.NewCrawler(op)
    c.FilterOpts.End, err = c.SafeBlockNum(3)
    contract, err := gum_gateway.NewGumGateway(c.Contract())
    iter, err := contract.FilterSold(c.FilterOpts, nil, nil)
    grpcClient := gateway.NewGatewayServiceClient(c.GRPC)
    for iter.Next() {
    e := iter.Event
    if e.Raw.Removed {
    fmt.Printf("level:info\tmsg:%s removed block\n", e.Raw.TxHash.String())
    continue
    }
    input := &gateway.PurchaseInfo{
    EthPurchaser: e.User.String(),
    EthAffiliator: e.Referrer.String(),
    EthAmountGwei: crawler.ToGwei(e.Value).Uint64(),
    TxHash: e.Raw.TxHash.String(),
    }
    if !op.DryRun {
    _, err := grpcClient.GumSale(context.Background(), input)
    if err != nil {
    if strings.HasPrefix(err.Error(), "rpc error: code = Unknown desc = Error 1062: Duplicate entry") {
    fmt.Printf("level:debug\tmsg:%s already affected\n", e.Raw.TxHash.String())
    continue
    }
    return err
    }
    }
    fmt.Printf("level:info\tmsg:%s is affected \n", e.Raw.TxHash.String())
    }
    

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34. ߟྀ఺
    Կ౓Ͱ΋͍͏͕ႈ౳ੑ͕ॏཁ
    ྫ͑͹ɺΦϑνΣʔϯͰॲཧΛߦͬͨͱ͍͏͜ͱΛ
    Ethererum্ʹه࿥͠Α͏ʹ΋࠶౓Tx͕ඞཁʹͳΔ
    EthereumͷTxHashΛ࢖ͬͯΦϑνΣʔϯଆͰႈ౳
    ੑΛ୲อ͢Δ
    DBͷҰҙ੍໿Ͱ࣮ݱ
    

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35. ߟྀ఺
    AssetΛϢʔβʔʹฦ͢৔߹΋ಉ͡ɻ
    ΦϑνΣʔϯͰTxHashతͳ΋ͷΛൃߦ͠ɺίϯτϥ
    ΫτʹΘͨ͢ɻ
    ίϯτϥΫτͰҰҙ੍໿ɺɺͱ͍ͨ͠ͱ͜Ζ͕ͩݱঢ়
    ͸Eventൃߦ͍ͯ͠Δ͚ͩ
    όον্ͰEventΛݟͯႈ౳ੑΛ୲อ
    

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36. ߟྀ఺
    SafeBlockͱ͍͏ߟ͑
    ϒϩοΫνΣʔϯͳͷͰreorg͕͋Γ͑Δ
    nϒϩοΫܦͬͨΒ֬ఆͱΈͳ͢
    Ϣʔβʔͷࢿ࢈ΛकΔͨΊʢ͜ͷล͸҉߸௨՟औҾ
    ॴ͞Μͷ΄͏͕ৄ͍͠͸ͣɺɺʣ
    γεςϜతʹ໊લ͍ͭͯͨΓ͠·͔͢Ͷʁ
    

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37. ·ͱΊ
    EthereumͰɺήʔϜͷΑ͏ͳෳࡶͳϩδοΫΛ࣮૷
    ͢Δͷ͸ෆՄೳ
    αʔϏεͱͯ͠ੈͷதʹग़ͨ͢ΊʹɺͲ͏͢Ε͹࣮
    ݱͰ͖Δ͔ྗٕͰ͜ͳ͍ͯ͘͠
    ਺গͳ͍ࣄྫͩͱࢥ͏ͷͰԕྀͳ࣭͘໰ͯͩ͘͠͞
    ͍ʂ
    

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38. RE-BUILDING THE FUTURE OF GAMING
    WITH BLOCKCHAIN TECHNOLOGY
    

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39. ࣌ؒ༨ͬͨΒ஻Δωλ
    ࣮ࡍʹMainnetͰ΍Δͱ৭ʑπϥΠ
    OperatorRoleͷඞཁੑ
    CS໨ઢͰͷGas
    gRPC-webΛ࢖ͬͨSPAΞϓϦέʔγϣϯ
    ecrecover࢖ͬͨϩάΠϯػೳ
    Loom SDKΫϥελߏங
    Loom Go Plugin։ൃ
    αʔόʔϨε୹ॖURL੡଄ػ
    IPFS΁ͷը૾౤ߘػೳ
    ERC721 Metadataʹ͍ͭͯ
    ϒϩοΫνΣʔϯήʔϜΤίγεςϜʹ͍ͭͯͷ࢛ํࢁ࿩
    ೔ຊʹ͓͚ΔNon Fungible Token
    αΠυνΣʔϯɺϦΞϧӡ༻ݶք
    

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