Constant function returns empty array + web3js

Question

I have a simple solidity script where I tested in remix (injected Web3 using geth local environment) and worked fine returning an array of data from a constant method.

pragma solidity ^0.4.11;

contract TestBetting {

  struct BettingInfo {    
      uint256 matchId;
      uint homeTeamScore;
      uint awayTeamScore;     
      uint bettingPrice;  
  }

  address public owner;
  mapping(address => BettingInfo[]) public bettingInfo;

 // constructor
  function MyBetting() {
    owner = msg.sender;
  }

  // Fall back 
  function () payable {}

  event LogDeposit(address sender, uint amount);

  // Place a bet  
  function placeBet(uint256 _matchId, 
                    uint _homeTeamScore, 
                    uint _awayTeamScore, 
                    uint _bettingPrice) payable returns (bool) {

    bettingInfo[msg.sender].push(
      BettingInfo(_matchId, _homeTeamScore, _awayTeamScore, _bettingPrice)); 

    require(_bettingPrice == msg.value); 
    this.transfer(msg.value); 

    LogDeposit(msg.sender, msg.value);

    return true;
  }

  function getBettingInfo(address _better) public constant returns (uint256[], uint[], uint[], uint[]) {
    uint length = bettingInfo[_better].length;
    uint256[] memory matchId = new uint256[](length);
    uint[] memory homeTeamScore = new uint[](length);
    uint[] memory awayTeamScore = new uint[](length);
    uint[] memory bettingPrice = new uint[](length);   

    for (uint i = 0; i < length; i++) {
      matchId[i] = bettingInfo[_better][i].matchId;
      homeTeamScore[i] = bettingInfo[_better][i].homeTeamScore;
      awayTeamScore[i] = bettingInfo[_better][i].awayTeamScore;
      bettingPrice[i] = bettingInfo[_better][i].bettingPrice;   
    }

    return (matchId, homeTeamScore, awayTeamScore, bettingPrice);
  }
}

When I do this in angular 5 with Geth local environment, first I need to submit transaction through placeBet method.

submit(form: NgForm): void {  
    this.bettingPrice = 20;
    this.bettingPrice = this.web3.toWei(this.bettingPrice, "ether");

    this.TestBetting.deployed().then((instance) => {
        return instance.placeBet(this.matchId, 
                                 this.homeTeamScore, 
                                 this.awayTeamScore, 
                                 this.bettingPrice, {
            from: this.account,
            value: this.bettingPrice,
            gas: 50000
        });
      })
      .then((value) => {
        console.log(value);
      })
      .catch((e) => {
        console.log(e);
      }); 
  }

It will open up metamask and it looks like it went through.

Now, I want to call getBettingInfo to see the data I submitted into network.

  loadGetBettingInfo() {   
    this.TestBetting.deployed().then((instance) => {
        return instance.getBettingInfo.call(this.betterAddress, {
            from: this.betterAddress,
            gas: 50000
        });
      })
      .then((value) => {
        console.log(value);
      })
      .catch((e) => {
        console.log(e);
      }); 
    }

But this returns an empty array in the console.

Can anyone see what I'm doing wrong here?

Answer 1

This is becausethis.TestBetting.deployed().then((instance) is creating the new instance every time which doesn't possess the previous state changes. So you need to create one instance and use it for all functions access.