Solidity struct arrar - solidity

Question

I'm running into a problem with solidity with structures containing arrays, can you help me see what I'm missing?Any help would be greatly appreciated!
struct Info {
uint a;
uint256 b;
uint[] data;
}
mapping(address => Info) infos;
function set() public {
infos[msg.sender].a = 1;
infos[msg.sender].b = 2;
infos[msg.sender].data.push(3);
}
function get() public {
infos[msg.sender].a; //yes It is equal to 1
infos[msg.sender].b; //yes It is equal to 2
infos[msg.sender].data[0]; //The problem here is that anyone calling this function can read data[0]=3
}

Answer 1

I am a little confused as to what you require, but first solution I have provided modifies your Smart Contract such that mapping object infos and the getter function is both private (available only in the Contract defined).
contract test{
struct Info {
uint a;
uint b;
uint[] data;
}
mapping(address => Info) private infos;
function set() public {
infos[msg.sender].a = 1;
infos[msg.sender].b = 2;
infos[msg.sender].data.push(3);
}
function get() private view{
infos[msg.sender].a; //yes It is equal to 1
infos[msg.sender].b; //yes It is equal to 2
infos[msg.sender].data[0]; //The problem here is that anyone calling this function can read data[0]=3
} }
Second solution is to add something called 'require' in the getter function so that only the person who deploys the Smart Contract can view the array index. The constructor function assigns the person who deploys the contract as the 'owner'.
contract test{
struct Info {
uint a;
uint b;
uint[] data;
}
address owner;
constructor() {
owner = msg.sender;
}
mapping(address => Info) infos;
function set() public {
infos[msg.sender].a = 1;
infos[msg.sender].b = 2;
infos[msg.sender].data.push(3);
}
function get() public view{
infos[msg.sender].a; //yes It is equal to 1
infos[msg.sender].b; //yes It is equal to 2
require(owner == msg.sender, 'you cannot read this data, you are not the owner!');
infos[msg.sender].data[0]; //The problem here is that anyone calling this function can read data[0]=3
}
}
Let me know if I have misunderstood your question.