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How to create a paid keyvalue store
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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
asked 1 hour ago
thewonderedthewondered
161
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thewondered is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
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
asked 1 hour ago
thewonderedthewondered
161
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.
add a comment |
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
asked 1 hour ago
thewonderedthewondered
161
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
contract-development contract-design
asked 1 hour ago
thewonderedthewondered
161
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.
asked 1 hour ago
thewonderedthewondered
161
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.
asked 1 hour ago
thewonderedthewondered
161
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.
asked 1 hour ago
thewonderedthewondered
161
asked 1 hour ago
thewonderedthewondered
161
161
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.
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.
thewondered is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
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;
}
}
answered 46 mins ago
Achala DissanayakeAchala Dissanayake
3,74481629
add a comment |
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
answered 46 mins ago
Miguel MotaMiguel Mota
2,8421027
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
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;
}
}
answered 46 mins ago
Achala DissanayakeAchala Dissanayake
3,74481629
add a comment |
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;
}
}
answered 46 mins ago
Achala DissanayakeAchala Dissanayake
3,74481629
add a comment |
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;
}
}
answered 46 mins ago
Achala DissanayakeAchala Dissanayake
3,74481629
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;
}
}
answered 46 mins ago
Achala DissanayakeAchala Dissanayake
3,74481629
edited 22 mins ago
answered 46 mins ago
Achala DissanayakeAchala Dissanayake
3,74481629
answered 46 mins ago
Achala DissanayakeAchala Dissanayake
3,74481629
answered 46 mins ago
Achala DissanayakeAchala Dissanayake
3,74481629
3,74481629
add a comment |
add a comment |
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
answered 46 mins ago
Miguel MotaMiguel Mota
2,8421027
add a comment |
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
answered 46 mins ago
Miguel MotaMiguel Mota
2,8421027
add a comment |
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
answered 46 mins ago
Miguel MotaMiguel Mota
2,8421027
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
answered 46 mins ago
Miguel MotaMiguel Mota
2,8421027
edited 37 mins ago
answered 46 mins ago
Miguel MotaMiguel Mota
2,8421027
answered 46 mins ago
Miguel MotaMiguel Mota
2,8421027
answered 46 mins ago
Miguel MotaMiguel Mota
2,8421027
2,8421027
add a comment |
add a comment |
thewondered is a new contributor. Be nice, and check out our Code of Conduct.
thewondered is a new contributor. Be nice, and check out our Code of Conduct.
thewondered is a new contributor. Be nice, and check out our Code of Conduct.
thewondered is a new contributor. Be nice, and check out our Code of Conduct.
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