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I created a contract token using the Ethereum.org token solidity code. It has a function called transfer to send tokens between accounts:

function transfer(address _to, uint256 _value)

I need to now connect to this contract using web3, and then send a certain number of tokens generated to another account. I've been struggling with how to do this for quite some time and hoping this community could help. Here is what I have thus far, using web3 version 0.20.0:

const Web3 = require("web3");
const web3 = new Web3();
web3.setProvider(new 
web3.providers.HttpProvider("https://ropsten.infura.io/XXXXXX"));
var abi = [ {} ] // redacted on purpose
var count = web3.eth.getTransactionCount("0x9...");
var abiArray = abi;
var contractAddress = "0x2...";
var contract =  web3.eth.contract(abiArray).at(contractAddress);

var data = contract.transfer.getData("0x2...", 10000, {from: "0x9..."});
var gasPrice = web3.eth.gasPrice;
var gasLimit = 90000;

var rawTransaction = {
  "from": "0x9...",
  "nonce": web3.toHex(count),
  "gasPrice": web3.toHex(gasPrice),
  "gasLimit": web3.toHex(gasLimit),
  "to": "0x2...",
  "value": "0x1",
  "data": data,
  "chainId": 0x03
};

var privKey = new Buffer('XXXXXXXXXXXXXX', 'hex');
var tx = new Tx(rawTransaction);

tx.sign(privKey);
var serializedTx = tx.serialize();

web3.eth.sendRawTransaction('0x' + serializedTx.toString('hex'), function(err, hash) {
  if (!err)
      console.log(hash);
  else
      console.log(err);
});

This transaction works but it's sending ether as opposed to the actual ERC20 token. I'm really at a loss for why this is the case and would appreciate any help whatsoever.

Code for Token Contract:

contract Token {
    // Public variables of the token
    string public name;
    string public symbol;
    uint8 public decimals = 18;
    // 18 decimals is the strongly suggested default, avoid changing it
    uint256 public totalSupply;

    // This creates an array with all balances
    mapping (address => uint256) public balanceOf;
    mapping (address => mapping (address => uint256)) public allowance;

    // This generates a public event on the blockchain that will notify clients
    event Transfer(address indexed from, address indexed to, uint256 value);

    // This notifies clients about the amount burnt
    event Burn(address indexed from, uint256 value);

    /**
     * Constrctor function
     *
     * Initializes contract with initial supply tokens to the creator of the contract
     */
    function Token(
        uint256 initialSupply,
        string tokenName,
        string tokenSymbol
    ) public {
        totalSupply = initialSupply * 10 ** uint256(decimals);  // Update total supply with the decimal amount
        balanceOf[msg.sender] = totalSupply;                // Give the creator all initial tokens
        name = tokenName;                                   // Set the name for display purposes
        symbol = tokenSymbol;                               // Set the symbol for display purposes
    }

    /**
     * Internal transfer, only can be called by this contract
     */
    function _transfer(address _from, address _to, uint _value) internal {
        // Prevent transfer to 0x0 address. Use burn() instead
        require(_to != 0x0);
        // Check if the sender has enough
        require(balanceOf[_from] >= _value);
        // Check for overflows
        require(balanceOf[_to] + _value > balanceOf[_to]);
        // Save this for an assertion in the future
        uint previousBalances = balanceOf[_from] + balanceOf[_to];
        // Subtract from the sender
        balanceOf[_from] -= _value;
        // Add the same to the recipient
        balanceOf[_to] += _value;
        Transfer(_from, _to, _value);
        // Asserts are used to use static analysis to find bugs in your code. They should never fail
        assert(balanceOf[_from] + balanceOf[_to] == previousBalances);
    }

    /**
     * Transfer tokens
     *
     * Send `_value` tokens to `_to` from your account
     *
     * @param _to The address of the recipient
     * @param _value the amount to send
     */
    function transfer(address _to, uint256 _value) public {
        _transfer(msg.sender, _to, _value);
    }

    /**
     * Transfer tokens from other address
     *
     * Send `_value` tokens to `_to` in behalf of `_from`
     *
     * @param _from The address of the sender
     * @param _to The address of the recipient
     * @param _value the amount to send
     */
    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
        require(_value <= allowance[_from][msg.sender]);     // Check allowance
        allowance[_from][msg.sender] -= _value;
        _transfer(_from, _to, _value);
        return true;
    }

    /**
     * Set allowance for other address
     *
     * Allows `_spender` to spend no more than `_value` tokens in your behalf
     *
     * @param _spender The address authorized to spend
     * @param _value the max amount they can spend
     */
    function approve(address _spender, uint256 _value) public
        returns (bool success) {
        allowance[msg.sender][_spender] = _value;
        return true;
    }

    /**
     * Set allowance for other address and notify
     *
     * Allows `_spender` to spend no more than `_value` tokens in your behalf, and then ping the contract about it
     *
     * @param _spender The address authorized to spend
     * @param _value the max amount they can spend
     * @param _extraData some extra information to send to the approved contract
     */
    function approveAndCall(address _spender, uint256 _value, bytes _extraData)
        public
        returns (bool success) {
        tokenRecipient spender = tokenRecipient(_spender);
        if (approve(_spender, _value)) {
            spender.receiveApproval(msg.sender, _value, this, _extraData);
            return true;
        }
    }

    /**
     * Destroy tokens
     *
     * Remove `_value` tokens from the system irreversibly
     *
     * @param _value the amount of money to burn
     */
    function burn(uint256 _value) public returns (bool success) {
        require(balanceOf[msg.sender] >= _value);   // Check if the sender has enough
        balanceOf[msg.sender] -= _value;            // Subtract from the sender
        totalSupply -= _value;                      // Updates totalSupply
        Burn(msg.sender, _value);
        return true;
    }

    /**
     * Destroy tokens from other ccount
     *
     * Remove `_value` tokens from the system irreversibly on behalf of `_from`.
     *
     * @param _from the address of the sender
     * @param _value the amount of money to burn
     */
    function burnFrom(address _from, uint256 _value) public returns (bool success) {
        require(balanceOf[_from] >= _value);                // Check if the targeted balance is enough
        require(_value <= allowance[_from][msg.sender]);    // Check allowance
        balanceOf[_from] -= _value;                         // Subtract from the targeted balance
        allowance[_from][msg.sender] -= _value;             // Subtract from the sender's allowance
        totalSupply -= _value;                              // Update totalSupply
        Burn(_from, _value);
        return true;
    }
}
  • Are you sure the transfer of ether is successful? Most token contracts will not accept ether with a transfer and the transaction should fail since you are sending 1 wei. Another thing to check is the gas amount. – Ismael Oct 29 '17 at 18:57
  • @Ismael yes it was successful, please see this link to etherscan: ropsten.etherscan.io/tx/… – Viper Oct 29 '17 at 19:14
  • You are sending the transaction to an external owned account, it should be to the contract address. – Ismael Oct 29 '17 at 20:14
  • @Ismael I changed the to address to the contract and it still does not send the tokens, please advise! ropsten.etherscan.io/tx/… – Viper Oct 29 '17 at 20:44
  • Without the contract source it is very hard to say something. Try with value set to zero. As I said early most tokens do not accept payments in their transfer method. – Ismael Oct 29 '17 at 21:35
1

The problem is that you are sending a non-zero value (1gwei in your example). If you want to transfer tokens then you have to set value to zero.

var rawTransaction = {
  "value": 0,
   ...
};

The reason is because for security functions that receive ether must have the payable modifier. Your transfer function doesn't have that modifier, and will reject any transaction with a non zero amount of ether.

function transfer(address _to, uint256 _value) public {
    _transfer(msg.sender, _to, _value);
}
  • thanks for your continued help but I'm afraid this still hasn't fixed the issue. I changed the value to 0 and it is still not sending the actual token: ropsten.etherscan.io/tx/… – Viper Oct 30 '17 at 4:34
  • @Viper You didn't fix the value, it is still showing 48 wei in that transaction. I think I've a mistake in my example, try using "value": 0 (the 0 without the quotes), or removing directly the "value" line. – Ismael Oct 30 '17 at 5:08

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