How to create a paid keyvalue store












3















I'd like to create a contract through which people can set publicly available key=value information in exchange for some Ether sent to me (the owner of the contract).
This is to create a public decentralized database on which anyone can read and write, and the Ether cost would be to limit spam.



However, I'd like it to be free for all users to retrieve any key stored in the contract. My understanding of Ethereum is limited, is this possible?










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    3















    I'd like to create a contract through which people can set publicly available key=value information in exchange for some Ether sent to me (the owner of the contract).
    This is to create a public decentralized database on which anyone can read and write, and the Ether cost would be to limit spam.



    However, I'd like it to be free for all users to retrieve any key stored in the contract. My understanding of Ethereum is limited, is this possible?










    share|improve this question







    New contributor




    thewondered is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.























      3












      3








      3








      I'd like to create a contract through which people can set publicly available key=value information in exchange for some Ether sent to me (the owner of the contract).
      This is to create a public decentralized database on which anyone can read and write, and the Ether cost would be to limit spam.



      However, I'd like it to be free for all users to retrieve any key stored in the contract. My understanding of Ethereum is limited, is this possible?










      share|improve this question







      New contributor




      thewondered is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.












      I'd like to create a contract through which people can set publicly available key=value information in exchange for some Ether sent to me (the owner of the contract).
      This is to create a public decentralized database on which anyone can read and write, and the Ether cost would be to limit spam.



      However, I'd like it to be free for all users to retrieve any key stored in the contract. My understanding of Ethereum is limited, is this possible?







      contract-development contract-design






      share|improve this question







      New contributor




      thewondered is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











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      New contributor




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      asked 1 hour ago









      thewonderedthewondered

      161




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          2 Answers
          2






          active

          oldest

          votes


















          2















          I'd like to create a contract through which people can set publicly
          available key=value information




          You can use a mapping to store data and public method to set values




          exchange for some Ether sent to me (the owner of the contract)




          You can make the set method payable and check for an amount of Ether from sender




          I'd like it to be free for all users to retrieve any key stored in the
          contract




          You can create the function a view one so no cost or transaction invlolved in reading values




          is this possible?




          Yes, This looks possible. It would look like below.



          pragma solidity >=0.4.22 <0.6.0;

          contract Store {
          mapping(bytes32 => bytes32) public keyValStore;
          address payable public owner;
          uint storeFee;

          constructor(uint fee) public {
          owner = msg.sender; // setting contract creator address as the owner
          storeFee = fee; // setting a store fee for to set values
          }

          function set(bytes32 key, bytes32 value) public payable {
          require(msg.value >= storeFee); // check if Ether value is greater than the store fee
          owner.transfer(msg.value); // transfer Ether to owner account
          keyValStore[key] = value; // setting the key value pair in mapping
          }

          function get(bytes32 key) public view returns (bytes32) {
          bytes32 val = keyValStore[key]; // get the relavant value for the given key
          return val;
          }
          }





          share|improve this answer

































            0














            Yes it's possible, here's an example key/value store contract to help you get started that requires 1 ether to set a key/value and anyone can read the data for free:



            pragma solidity >=0.4.22 <0.6.0;
            contract Store {
            mapping(bytes32 => bytes32) private store;
            mapping(bytes32 => address) private authors;
            address private owner;

            constructor() public {
            owner = msg.sender;
            }

            function set(bytes32 key, bytes32 value) public payable {
            require(msg.value == 1 ether);
            require(store[key] == 0 || authors[key] == msg.sender);
            store[key] = value;
            authors[key] = msg.sender;
            }

            function get(bytes32 key) public view returns(bytes32) {
            return store[key];
            }

            function withdraw(address payable receiver) public {
            require(msg.sender == owner);
            receiver.transfer(address(this).balance);
            }
            }


            https://rinkeby.etherscan.io/address/0xf7e0caef5cd7a18d31343670b60ff463fa23d5c8






            share|improve this answer

























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              2 Answers
              2






              active

              oldest

              votes








              2 Answers
              2






              active

              oldest

              votes









              active

              oldest

              votes






              active

              oldest

              votes









              2















              I'd like to create a contract through which people can set publicly
              available key=value information




              You can use a mapping to store data and public method to set values




              exchange for some Ether sent to me (the owner of the contract)




              You can make the set method payable and check for an amount of Ether from sender




              I'd like it to be free for all users to retrieve any key stored in the
              contract




              You can create the function a view one so no cost or transaction invlolved in reading values




              is this possible?




              Yes, This looks possible. It would look like below.



              pragma solidity >=0.4.22 <0.6.0;

              contract Store {
              mapping(bytes32 => bytes32) public keyValStore;
              address payable public owner;
              uint storeFee;

              constructor(uint fee) public {
              owner = msg.sender; // setting contract creator address as the owner
              storeFee = fee; // setting a store fee for to set values
              }

              function set(bytes32 key, bytes32 value) public payable {
              require(msg.value >= storeFee); // check if Ether value is greater than the store fee
              owner.transfer(msg.value); // transfer Ether to owner account
              keyValStore[key] = value; // setting the key value pair in mapping
              }

              function get(bytes32 key) public view returns (bytes32) {
              bytes32 val = keyValStore[key]; // get the relavant value for the given key
              return val;
              }
              }





              share|improve this answer






























                2















                I'd like to create a contract through which people can set publicly
                available key=value information




                You can use a mapping to store data and public method to set values




                exchange for some Ether sent to me (the owner of the contract)




                You can make the set method payable and check for an amount of Ether from sender




                I'd like it to be free for all users to retrieve any key stored in the
                contract




                You can create the function a view one so no cost or transaction invlolved in reading values




                is this possible?




                Yes, This looks possible. It would look like below.



                pragma solidity >=0.4.22 <0.6.0;

                contract Store {
                mapping(bytes32 => bytes32) public keyValStore;
                address payable public owner;
                uint storeFee;

                constructor(uint fee) public {
                owner = msg.sender; // setting contract creator address as the owner
                storeFee = fee; // setting a store fee for to set values
                }

                function set(bytes32 key, bytes32 value) public payable {
                require(msg.value >= storeFee); // check if Ether value is greater than the store fee
                owner.transfer(msg.value); // transfer Ether to owner account
                keyValStore[key] = value; // setting the key value pair in mapping
                }

                function get(bytes32 key) public view returns (bytes32) {
                bytes32 val = keyValStore[key]; // get the relavant value for the given key
                return val;
                }
                }





                share|improve this answer




























                  2












                  2








                  2








                  I'd like to create a contract through which people can set publicly
                  available key=value information




                  You can use a mapping to store data and public method to set values




                  exchange for some Ether sent to me (the owner of the contract)




                  You can make the set method payable and check for an amount of Ether from sender




                  I'd like it to be free for all users to retrieve any key stored in the
                  contract




                  You can create the function a view one so no cost or transaction invlolved in reading values




                  is this possible?




                  Yes, This looks possible. It would look like below.



                  pragma solidity >=0.4.22 <0.6.0;

                  contract Store {
                  mapping(bytes32 => bytes32) public keyValStore;
                  address payable public owner;
                  uint storeFee;

                  constructor(uint fee) public {
                  owner = msg.sender; // setting contract creator address as the owner
                  storeFee = fee; // setting a store fee for to set values
                  }

                  function set(bytes32 key, bytes32 value) public payable {
                  require(msg.value >= storeFee); // check if Ether value is greater than the store fee
                  owner.transfer(msg.value); // transfer Ether to owner account
                  keyValStore[key] = value; // setting the key value pair in mapping
                  }

                  function get(bytes32 key) public view returns (bytes32) {
                  bytes32 val = keyValStore[key]; // get the relavant value for the given key
                  return val;
                  }
                  }





                  share|improve this answer
















                  I'd like to create a contract through which people can set publicly
                  available key=value information




                  You can use a mapping to store data and public method to set values




                  exchange for some Ether sent to me (the owner of the contract)




                  You can make the set method payable and check for an amount of Ether from sender




                  I'd like it to be free for all users to retrieve any key stored in the
                  contract




                  You can create the function a view one so no cost or transaction invlolved in reading values




                  is this possible?




                  Yes, This looks possible. It would look like below.



                  pragma solidity >=0.4.22 <0.6.0;

                  contract Store {
                  mapping(bytes32 => bytes32) public keyValStore;
                  address payable public owner;
                  uint storeFee;

                  constructor(uint fee) public {
                  owner = msg.sender; // setting contract creator address as the owner
                  storeFee = fee; // setting a store fee for to set values
                  }

                  function set(bytes32 key, bytes32 value) public payable {
                  require(msg.value >= storeFee); // check if Ether value is greater than the store fee
                  owner.transfer(msg.value); // transfer Ether to owner account
                  keyValStore[key] = value; // setting the key value pair in mapping
                  }

                  function get(bytes32 key) public view returns (bytes32) {
                  bytes32 val = keyValStore[key]; // get the relavant value for the given key
                  return val;
                  }
                  }






                  share|improve this answer














                  share|improve this answer



                  share|improve this answer








                  edited 17 mins ago

























                  answered 40 mins ago









                  Achala DissanayakeAchala Dissanayake

                  3,74481629




                  3,74481629























                      0














                      Yes it's possible, here's an example key/value store contract to help you get started that requires 1 ether to set a key/value and anyone can read the data for free:



                      pragma solidity >=0.4.22 <0.6.0;
                      contract Store {
                      mapping(bytes32 => bytes32) private store;
                      mapping(bytes32 => address) private authors;
                      address private owner;

                      constructor() public {
                      owner = msg.sender;
                      }

                      function set(bytes32 key, bytes32 value) public payable {
                      require(msg.value == 1 ether);
                      require(store[key] == 0 || authors[key] == msg.sender);
                      store[key] = value;
                      authors[key] = msg.sender;
                      }

                      function get(bytes32 key) public view returns(bytes32) {
                      return store[key];
                      }

                      function withdraw(address payable receiver) public {
                      require(msg.sender == owner);
                      receiver.transfer(address(this).balance);
                      }
                      }


                      https://rinkeby.etherscan.io/address/0xf7e0caef5cd7a18d31343670b60ff463fa23d5c8






                      share|improve this answer






























                        0














                        Yes it's possible, here's an example key/value store contract to help you get started that requires 1 ether to set a key/value and anyone can read the data for free:



                        pragma solidity >=0.4.22 <0.6.0;
                        contract Store {
                        mapping(bytes32 => bytes32) private store;
                        mapping(bytes32 => address) private authors;
                        address private owner;

                        constructor() public {
                        owner = msg.sender;
                        }

                        function set(bytes32 key, bytes32 value) public payable {
                        require(msg.value == 1 ether);
                        require(store[key] == 0 || authors[key] == msg.sender);
                        store[key] = value;
                        authors[key] = msg.sender;
                        }

                        function get(bytes32 key) public view returns(bytes32) {
                        return store[key];
                        }

                        function withdraw(address payable receiver) public {
                        require(msg.sender == owner);
                        receiver.transfer(address(this).balance);
                        }
                        }


                        https://rinkeby.etherscan.io/address/0xf7e0caef5cd7a18d31343670b60ff463fa23d5c8






                        share|improve this answer




























                          0












                          0








                          0







                          Yes it's possible, here's an example key/value store contract to help you get started that requires 1 ether to set a key/value and anyone can read the data for free:



                          pragma solidity >=0.4.22 <0.6.0;
                          contract Store {
                          mapping(bytes32 => bytes32) private store;
                          mapping(bytes32 => address) private authors;
                          address private owner;

                          constructor() public {
                          owner = msg.sender;
                          }

                          function set(bytes32 key, bytes32 value) public payable {
                          require(msg.value == 1 ether);
                          require(store[key] == 0 || authors[key] == msg.sender);
                          store[key] = value;
                          authors[key] = msg.sender;
                          }

                          function get(bytes32 key) public view returns(bytes32) {
                          return store[key];
                          }

                          function withdraw(address payable receiver) public {
                          require(msg.sender == owner);
                          receiver.transfer(address(this).balance);
                          }
                          }


                          https://rinkeby.etherscan.io/address/0xf7e0caef5cd7a18d31343670b60ff463fa23d5c8






                          share|improve this answer















                          Yes it's possible, here's an example key/value store contract to help you get started that requires 1 ether to set a key/value and anyone can read the data for free:



                          pragma solidity >=0.4.22 <0.6.0;
                          contract Store {
                          mapping(bytes32 => bytes32) private store;
                          mapping(bytes32 => address) private authors;
                          address private owner;

                          constructor() public {
                          owner = msg.sender;
                          }

                          function set(bytes32 key, bytes32 value) public payable {
                          require(msg.value == 1 ether);
                          require(store[key] == 0 || authors[key] == msg.sender);
                          store[key] = value;
                          authors[key] = msg.sender;
                          }

                          function get(bytes32 key) public view returns(bytes32) {
                          return store[key];
                          }

                          function withdraw(address payable receiver) public {
                          require(msg.sender == owner);
                          receiver.transfer(address(this).balance);
                          }
                          }


                          https://rinkeby.etherscan.io/address/0xf7e0caef5cd7a18d31343670b60ff463fa23d5c8







                          share|improve this answer














                          share|improve this answer



                          share|improve this answer








                          edited 31 mins ago

























                          answered 40 mins ago









                          Miguel MotaMiguel Mota

                          2,8421027




                          2,8421027






















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