EOSIO Developer Portal 解説　データの永続化とインラインアクション 第3回

はじめに

インラインアクションとは

インラインアクションの実装と動作確認

addressbookコントラクトの修正

public:
  ...
  [[eosio::action]]
  void notify(name user, std::string msg) {
    require_auth(get_self());
    require_recipient(user);
  }

private:
  struct [[eosio::table]] person {
    ...
  };

  void send_summary(name user, std::string message) {
    action(
      permission_level{get_self(),"active"_n},
      get_self(),
      "notify"_n,
      std::make_tuple(user, name{user}.to_string() + message)
    ).send();
  };

  [[eosio::action]]
  void upsert(name user, std::string first_name, std::string last_name, uint64_t age, std::string street, std::string city, std::string state) {
    ...
    if( iterator == addresses.end() )
    {
      ...
      send_summary(user, " successfully emplaced record to addressbook");
    }
    else {
      ...
      send_summary(user, " successfully modified record to addressbook");
    }
  }

  [[eosio::action]]
  void erase(name user) {
    ...
    send_summary(user, " successfully erased record from addressbook");
  }

EOSIO_DISPATCH( addressbook, (upsert)(notify)(erase))

$ eosio-cpp -o addressbook.wasm addressbook.cpp --abigen

$ cleos set contract addressbook CONTRACTS_DIR/addressbook

パーミッションの追加と動作確認

$ cleos push action addressbook upsert '["alice", "alice", "liddell", 21, "123 drink me way", "wonderland", "amsterdam"]' -p alice@active

Error 3100006: Subjective exception thrown during block production

$ cleos get account addressbook

created: 2019-02-25T03:21:10.000
permissions:
     owner     1:    1 EOS6MRyAjQq8ud7hVNYcfnVPJqcVpscN5So8BhtHuGYqET5GDW5CV
        active     1:    1 EOS6MRyAjQq8ud7hVNYcfnVPJqcVpscN5So8BhtHuGYqET5GDW5CV

$ cleos set account permission addressbook active --add-code

$ cleos get account addressbook

created: 2019-02-25T03:21:10.000
permissions:
     owner     1:    1 EOS6MRyAjQq8ud7hVNYcfnVPJqcVpscN5So8BhtHuGYqET5GDW5CV
        active     1:    1 EOS6MRyAjQq8ud7hVNYcfnVPJqcVpscN5So8BhtHuGYqET5GDW5CV, 1 addressbook@eosio.code

$ cleos get actions alice

#  seq  when                              contract::action => receiver      trx id...   args
===============================================================
#   62   2018-09-15T12:57:09.000       addressbook::notify => alice         685ecc09... {"user":"alice","msg":"alice successfully added record to ad...

外部コントラクトのアクション実行

abcounterコントラクトの実装

$ cd CONTRACTS_DIR
$ mkdir abcounter
$ cd abcounter
$ touch abcounter.cpp

#include 

using namespace eosio;

class [[eosio::contract]] abcounter : public eosio::contract {
  public:
    using contract::contract;

    abcounter(name receiver, name code,  datastream ds): contract(receiver, code, ds) {}

    [[eosio::action]]
    void count(name user, std::string type) {
      require_auth( name("addressbook"));
      count_index counts(name(_code), _code.value);
      auto iterator = counts.find(user.value);
      
      if (iterator == counts.end()) {
        counts.emplace("addressbook"_n, [&]( auto& row ) {
          row.key = user;
          row.emplaced = (type == "emplace") ? 1 : 0;
          row.modified = (type == "modify") ? 1 : 0;
          row.erased = (type == "erase") ? 1 : 0;
        });
      }
      else {
        counts.modify(iterator, "addressbook"_n, [&]( auto& row ) {
          if(type == "emplace") { row.emplaced += 1; }
          if(type == "modify") { row.modified += 1; }
          if(type == "erase") { row.erased += 1; }
        });
      }
    }

  private:
    struct [[eosio::table]] counter {
      name key;
      uint64_t emplaced;
      uint64_t modified;
      uint64_t erased;
      uint64_t primary_key() const { return key.value; }
    };

    using count_index = eosio::multi_index<"counts"_n, counter>;
};

EOSIO_DISPATCH( abcounter, (count));

$ cleos create account eosio abcounter YOUR_PUBLIC_KEY

$ eosio-cpp -o abcounter.wasm abcounter.cpp --abigen

$ cleos set contract abcounter CONTRACTS_DIR/abcounter

addressbookコントラクトの修正

$ cd CONTRACTS_DIR/addressbook

public:
  ...
  [[eosio::action]]
  void upsert(...) {
    ...
    if( iterator == addresses.end() )
    {
       ...
       increment_counter(user, "emplace");
      });
    }
    else {
       ...
       increment_counter(user, "modify");
      });

    }
  }

  [[eosio::action]]
  void erase(name user) {
    ...
    increment_counter(user, "erase");
  }

...

private:
  struct [[eosio::table]] person {
    ...
  };

  void send_summary(name user, std::string message) {
    ...
  };

  void increment_counter(name user, std::string type) {
    
    action counter = action(
      permission_level{get_self(),"active"_n},
      "abcounter"_n,
      "count"_n,
      std::make_tuple(user, type)
    );

    counter.send();
  }

    ...
};

$ eosio-cpp -o addressbook.wasm addressbook.cpp

$ cleos set contract addressbook CONTRACTS_DIR/addressbook

動作確認

$ cleos push action addressbook upsert '["alice", "alice", "liddell", 19, "123 drink me way", "wonderland", "amsterdam"]' -p alice@active

executed transaction: cc46f20da7fc431124e418ecff90aa882d9ca017a703da78477b381a0246eaf7  152 bytes  1493 us
#   addressbook <= addressbook::upsert          {"user":"alice","first_name":"alice","last_name":"liddell","street":"123 drink me way","city":"wonde...
#   addressbook <= addressbook::notify          {"user":"alice","msg":"alice successfully modified record in addressbook"}
#         alice <= addressbook::notify          {"user":"alice","msg":"alice successfully modified record in addressbook"}
#     abcounter <= abcounter::count             {"user":"alice","type":"modify"}

$ cleos get table abcounter abcounter counts --lower alice --limit 1

{
  "rows": [{
      "key": "alice",
      "emplaced": 0,
      "modified": 1,
      "erased": 0
    }
  ],
  "more": false
}

$ cleos push action addressbook erase '["alice"]' -p alice@active

executed transaction: aa82577cb1efecf7f2871eac062913218385f6ab2597eaf31a4c0d25ef1bd7df  104 bytes  973 us
#   addressbook <= addressbook::erase           {"user":"alice"}
>> Erased
#   addressbook <= addressbook::notify          {"user":"alice","msg":"alice successfully erased record from addressbook"}
>> Notified
#         alice <= addressbook::notify          {"user":"alice","msg":"alice successfully erased record from addressbook"}
#     abcounter <= abcounter::count             {"user":"alice","type":"erase"}
warning: transaction executed locally, but may not be confirmed by the network yet    ]

$ cleos push action addressbook upsert '["alice", "alice", "liddell", 21,"1 there we go", "wonderland", "amsterdam"]' -p alice@active

executed transaction: c819ffeade670e3b44a40f09cf4462384d6359b5e44dd211f4367ac6d3ccbc70  152 bytes  909 us
#   addressbook <= addressbook::upsert          {"user":"alice","first_name":"alice","last_name":"liddell","street":"1 coming down","city":"normalla...
#   addressbook <= addressbook::notify          {"user":"alice","msg":"alice successfully emplaced record to addressbook"}
>> Notified
#         alice <= addressbook::notify          {"user":"alice","msg":"alice successfully emplaced record to addressbook"}
#     abcounter <= abcounter::count             {"user":"alice","type":"emplace"}
warning: transaction executed locally, but may not be confirmed by the network yet    ]

$ cleos get table abcounter abcounter counts --lower alice 

{
  "rows": [{
      "key": "alice",
      "emplaced": 1,
      "modified": 1,
      "erased": 1
    }
  ],
  "more": false
}

参考文献：

• EOSIO Developer Portal – 2.6 Adding Inline Actions
  
  https://developers.eos.io/eosio-home/docs/inline-actions
  
• EOSIO Developer Portal – 2.7 Inline Action to External Contract
  
  https://developers.eos.io/eosio-home/docs/sending-an-inline-transaction-to-external-contract
  
• EOSIO Developer Portal – Communication Model
  
  https://developers.eos.io/eosio-cpp/docs/communication-model
  
• EOSIO Developer Portal – Adding eosio.code to active authority with cleos’ helper
  
  https://developers.eos.io/eosio-cleos/docs/adding-eosiocode-to-active-authority-with-cleos-helper