How to create a paid keyvalue storeHow to interact with a smart contract in practice (for free)? A bigger...
Change the color of a single dot in `ddot` symbol
Why Shazam when there is already Superman?
Pre-mixing cryogenic fuels and using only one fuel tank
What features enable the Su-25 Frogfoot to operate with such a wide variety of fuels?
Is there a RAID 0 Equivalent for RAM?
How to make money from a browser who sees 5 seconds into the future of any web page?
Showing a sum is positive
How do you make your own symbol when Detexify fails?
Multiplicative persistence
Has any country ever had 2 former presidents in jail simultaneously?
What is Cash Advance APR?
What is going on with gets(stdin) on the site coderbyte?
What to do when eye contact makes your coworker uncomfortable?
Which Article Helped Get Rid of Technobabble in RPGs?
Stack Interview Code methods made from class Node and Smart Pointers
Does "he squandered his car on drink" sound natural?
Why does this expression simplify as such?
How does electrical safety system work on ISS?
Is there any evidence that Cleopatra and Caesarion considered fleeing to India to escape the Romans?
Why is the "ls" command showing permissions of files in a FAT32 partition?
Can a stoichiometric mixture of oxygen and methane exist as a liquid at standard pressure and some (low) temperature?
Quoting Keynes in a lecture
Does an advisor owe his/her student anything? Will an advisor keep a PhD student only out of pity?
Which was the first story featuring espers?
How to create a paid keyvalue store
How to interact with a smart contract in practice (for free)? A bigger picture!DApp storage for data other than tranactions?Create contract that receives and sends bonus money to many addresses. What is the gas price?Are API tokens incompatible with Ethereum apps?Best practices for handling payment in smart contractsStore specific data related to usersThe better way to integrate Ethereum payments into web applicationHow can I create a modifier that requires the msg.sender be one of multiple addresses?Smart Contract To Send Multiple OutputsHow does Ethereum Smart Contract work on Mobile Client
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.
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 55 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 55 mins ago
Miguel MotaMiguel Mota
2,8421027
add a comment |
Your Answer
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "642"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
thewondered is a new contributor. Be nice, and check out our Code of Conduct.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fethereum.stackexchange.com%2fquestions%2f68654%2fhow-to-create-a-paid-keyvalue-store%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
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 55 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 55 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 55 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 55 mins ago
Achala DissanayakeAchala Dissanayake
3,74481629
edited 32 mins ago
answered 55 mins ago
Achala DissanayakeAchala Dissanayake
3,74481629
answered 55 mins ago
Achala DissanayakeAchala Dissanayake
3,74481629
answered 55 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 55 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 55 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 55 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 55 mins ago
Miguel MotaMiguel Mota
2,8421027
edited 46 mins ago
answered 55 mins ago
Miguel MotaMiguel Mota
2,8421027
answered 55 mins ago
Miguel MotaMiguel Mota
2,8421027
answered 55 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.
Thanks for contributing an answer to Ethereum Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fethereum.stackexchange.com%2fquestions%2f68654%2fhow-to-create-a-paid-keyvalue-store%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
