geturi

geturi | code​
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/**
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  *  LiquidHarmony uses the geturi action to perform an oracle request
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  *
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  *  @param {std::vector<char>} uri - hex conversion of URL syntax to perform an oracle request
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  *  @param {Lambda&&} combinator - lambda to return the results of an oracle request
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  * 
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  *  Example:
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  *
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  *  @code
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  *  [[eosio::action]] void testrnd(std::vector<char> uri) {
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  *    getURI(uri, [&]( auto& results ) { 
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  *      return results[0].result;
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  *    });
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  *  }
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  *  @endcode
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  */
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​
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TABLE oracleentry {  \
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   uint64_t                      id; \
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   std::vector<char>             uri; \
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   std::vector<provider_result>     results; \
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   checksum256 hash_key() const { return hashData(uri); }  \
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   uint64_t primary_key()const { return id; }  \
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};  \
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typedef eosio::multi_index<"oracleentry"_n, oracleentry, indexed_by<"byhash"_n, const_mem_fun<oracleentry, checksum256, &oracleentry::hash_key>>> oracleentries_t; \
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​
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static std::vector<char> getURI(std::vector<char> uri, Lambda&& combinator){  \
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    checksum256 trxId = transaction_id(); \
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    auto trxIdp = trxId.data(); \
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    std::string trxIdStr(trxIdp, trxIdp + trxId.size()); \
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    auto pubTime = tapos_block_prefix(); \
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    std::string uristr(uri.begin(), uri.end()); \
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    auto s = fc::base64_encode(trxIdStr) + "://" + fc::to_string(pubTime) + "://" + uristr;\
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    std::vector<char> idUri(s.begin(), s.end()); \
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    return _getURI(idUri, combinator); \
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}\
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​
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static std::vector<char> _getURI(std::vector<char> uri, Lambda&& combinator){  \
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    auto _self = name(current_receiver()); \
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    oracleentries_t entries(_self, _self.value);  \
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    auto cidx = entries.get_index<"byhash"_n>(); \
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    auto existing = cidx.find(hashData(uri)); \
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    if(existing == cidx.end()){  \
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        SEND_SVC_REQUEST(geturi, uri); \
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    } \
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    else {\
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        auto results = _extractResults(*existing, combinator);\
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        cidx.erase(existing);\
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        return results; \
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    } \
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    return std::vector<char>();\
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}  \
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ORACLE_HOOK_FILTER

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geturi | code​

geturi | code