So I am using the following code

contract Damble is usingOraclize{

function Damble() {

    function __callback(bytes32 _queryId, string _result, bytes _proof) { 
    if (msg.sender != oraclize_cbAddress()) throw;

    if (oraclize_randomDS_proofVerify__returnCode(_queryId, _result, _proof) != 0) {
        // the proof verification has failed, do we need to take any action here? (depends on the use case)
    } else {
        // the proof verification has passed
        // now that we know that the random number was safely generated, let's use it..

        newRandomNumber_bytes(bytes(_result)); // this is the resulting random number (bytes)

        // for simplicity of use, let's also convert the random bytes to uint if we need
        uint maxRange = 10000000; // this is the highest uint we want to get. It should never be greater than 2^(8*N), where N is the number of random bytes we had asked the datasource to return
        uint randomNumber = uint(sha3(_result)) % maxRange; // this is an efficient way to get the uint out in the [0, maxRange] range

        newRandomNumber_uint(randomNumber); // this is the resulting random number (uint)

function getRandomNumber() payable{ 
    oraclize_setProof(proofType_Ledger); // sets the Ledger authenticity proof
    uint N = 4; // number of random bytes we want the datasource to return
    uint delay = 0; // number of seconds to wait before the execution takes place
    uint callbackGas = 200000; // amount of gas we want Oraclize to set for the callback function
    bytes32 queryId = oraclize_newRandomDSQuery(delay, N, callbackGas);

The first time getRandomNumber() gets called from the constructor everything works fine. When I want to call getRandomNumber manually with a certain value (to pay for the Oraclize value) I need to put in more than $5 worth of eth that doesnt get spend otherwise the transaction fails but it dilutes my contracts ether balance. Other than that when i call getRandomNumber() after the constructor called from the constructor no events get fired even though a transaction comes in from the Oraclize address.

EDIT: this is a link to my contract: https://ropsten.etherscan.io/address/0x92f0dbf8b218e03f288da42c0f6d4df7de40c3f2

1 Answer 1


The problem seems to have solved itself, probably by having some balance within the contract itself.

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