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eosjs常用代码

eosjs Startup 整理了eosjs常用代码,包括创建、查询EOS账号,EOS转账,购买RAM,出售RAM,抵押资源,取消抵押资源,生成密钥对等。
https://github.com/dabdevelop/eosjs-startup

eos rpc get_table_rows index_position

https://github.com/EOSIO/eos/blob/686f0deb5dac097cc292f735ccb47c238e763de0/plugins/chain_plugin/chain_plugin.cpp#L1043

uint64_t read_only::get_table_index_name(const read_only::get_table_rows_params& p, bool& primary) {
   using boost::algorithm::starts_with;
   // see multi_index packing of index name
   const uint64_t table = p.table;
   uint64_t index = table & 0xFFFFFFFFFFFFFFF0ULL;
   EOS_ASSERT( index == table, chain::contract_table_query_exception, "Unsupported table name: ${n}", ("n", p.table) );

   primary = false;
   uint64_t pos = 0;
   if (p.index_position.empty() || p.index_position == "first" || p.index_position == "primary" || p.index_position == "one") {
      primary = true;
   } else if (starts_with(p.index_position, "sec") || p.index_position == "two") { // second, secondary
   } else if (starts_with(p.index_position , "ter") || starts_with(p.index_position, "th")) { // tertiary, ternary, third, three
      pos = 1;
   } else if (starts_with(p.index_position, "fou")) { // four, fourth
      pos = 2;
   } else if (starts_with(p.index_position, "fi")) { // five, fifth
      pos = 3;
   } else if (starts_with(p.index_position, "six")) { // six, sixth
      pos = 4;
   } else if (starts_with(p.index_position, "sev")) { // seven, seventh
      pos = 5;
   } else if (starts_with(p.index_position, "eig")) { // eight, eighth
      pos = 6;
   } else if (starts_with(p.index_position, "nin")) { // nine, ninth
      pos = 7;
   } else if (starts_with(p.index_position, "ten")) { // ten, tenth
      pos = 8;
   } else {
      try {
         pos = fc::to_uint64( p.index_position );
      } catch(...) {
         EOS_ASSERT( false, chain::contract_table_query_exception, "Invalid index_position: ${p}", ("p", p.index_position));
      }
      if (pos < 2) {
         primary = true;
         pos = 0;
      } else {
         pos -= 2;
      }
   }
   index |= (pos & 0x000000000000000FULL);
   return index;
}

Position of the index used, accepted parameters primary, secondary, tertiary, fourth, fifth, sixth, seventh, eighth, ninth , tenth

index_position 可以以某前缀的名字指定对应多级索引,或者数字(从2开始)

EOS 合约 table primary key支持的类型

https://github.com/EOSIO/eos/blob/5082391c60b0fa5e68157c385cd402bf25aea934/plugins/chain_plugin/chain_plugin.cpp#L1158

read_only::get_table_rows_result read_only::get_table_rows( const read_only::get_table_rows_params& p )const {
   const abi_def abi = eosio::chain_apis::get_abi( db, p.code );
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
   bool primary = false;
   auto table_with_index = get_table_index_name( p, primary );
   if( primary ) {
      EOS_ASSERT( p.table == table_with_index, chain::contract_table_query_exception, "Invalid table name ${t}", ( "t", p.table ));
      auto table_type = get_table_type( abi, p.table );
      if( table_type == KEYi64 || p.key_type == "i64" || p.key_type == "name" ) {
         return get_table_rows_ex<key_value_index>(p,abi);
      }
      EOS_ASSERT( false, chain::contract_table_query_exception,  "Invalid table type ${type}", ("type",table_type)("abi",abi));
   } else {
      EOS_ASSERT( !p.key_type.empty(), chain::contract_table_query_exception, "key type required for non-primary index" );

      if (p.key_type == chain_apis::i64 || p.key_type == "name") {
         return get_table_rows_by_seckey<index64_index, uint64_t>(p, abi, [](uint64_t v)->uint64_t {
            return v;
         });
      }
      else if (p.key_type == chain_apis::i128) {
         return get_table_rows_by_seckey<index128_index, uint128_t>(p, abi, [](uint128_t v)->uint128_t {
            return v;
         });
      }
      else if (p.key_type == chain_apis::i256) {
         if ( p.encode_type == chain_apis::hex) {
            using  conv = keytype_converter<chain_apis::sha256,chain_apis::hex>;
            return get_table_rows_by_seckey<conv::index_type, conv::input_type>(p, abi, conv::function());
         }
         using  conv = keytype_converter<chain_apis::i256>;
         return get_table_rows_by_seckey<conv::index_type, conv::input_type>(p, abi, conv::function());
      }

结论

primary key 只支持uint64_tcapi_name
如果想支持其他类型只能用
二级索引支持了 index_position + key_type

官方解释

它们是多索引表,因为它们支持在数据上使用多个索引,主索引类型必须是uint64_t并且必须是唯一的,但其他次要索引可以具有重复项。最多可以有16个附加索引,字段类型可以是uint64_t,uint128_t,eosio::checksum256,double或long double

参考

https://developers.eos.io/eosio-cpp/docs/using-multi-index-tables#section-introduction
https://developers.eos.io/eosio-nodeos/reference#get_table_rows
https://eosio.stackexchange.com/questions/3091/is-it-possible-to-use-a-type-other-than-uint64-t-for-a-table-primary-key/3097#3097

ScatterWebExtension popup window

https://github.com/GetScatter/ScatterWebExtension/blob/9d0f0946f8f53fe56c9a52afbeb55cc72c41f8e4/src/copied/prompt.html

https://github.com/GetScatter/ScatterWebExtension/blob/9d0f0946f8f53fe56c9a52afbeb55cc72c41f8e4/src/services/NotificationService.js#L38

const getPopup = async () => {
            try {
                const url = apis.runtime.getURL('/prompt.html');

                // Notifications get bound differently depending on browser
                // as Firefox does not support opening windows from background.
                if(typeof browser !== 'undefined') {
                    const created = await apis.windows.create({
                        url,
                        height,
                        width,
                        type:'popup'
                    });

                    window.notification = notification;
                    return created;
                }
                else {
                    const win = window.open(url, 'ScatterPrompt', `width=${width},height=${height},resizable=0,top=${middleY},left=${middleX},titlebar=0`);
                    win.data = notification;
                    openWindow = win;
                    return win;
                }
            } catch (e) {
                console.log('notification error', e);
                return null;
            }
        }