public ChainTask GetTask(StorageContext storage, BigInteger taskID)
{
var taskKey = GetTaskKey(taskID, "task_info");
var taskBytes = this.Storage.Get(taskKey);
var task = ChainTask.FromBytes(taskID, taskBytes);
return(task);
}
public ITask StartTask(StorageContext storage, Address from, string contractName, ContractMethod method, int frequency, TaskFrequencyMode mode, BigInteger gasLimit)
{
if (!IsContractDeployed(storage, contractName))
{
return(null);
}
var taskID = GenerateUID(storage);
var task = new ChainTask(taskID, from, contractName, method.name, (uint)frequency, mode, gasLimit, true);
var taskKey = GetTaskKey(taskID, "task_info");
var taskBytes = task.ToByteArray();
this.Storage.Put(taskKey, taskBytes);
var taskList = new StorageList(TaskListTag, this.Storage);
taskList.Add <BigInteger>(taskID);
return(task);
}
private TaskResult ProcessPendingTask(Block block, OracleReader oracle, BigInteger minimumFee, StorageChangeSetContext changeSet, bool allowModify, ChainTask task, out Transaction transaction)
{
transaction = null;
if (task.Mode != TaskFrequencyMode.Always)
{
var taskKey = GetTaskKey(task.ID, "task_run");
BigInteger lastRun = changeSet.Has(taskKey) ? changeSet.Get <BigInteger>(taskKey) : 0;
switch (task.Mode)
{
case TaskFrequencyMode.Blocks:
{
var diff = block.Height - lastRun;
if (diff < task.Frequency)
{
return(TaskResult.Skipped); // skip execution for now
}
break;
}
case TaskFrequencyMode.Time:
{
var diff = block.Timestamp.Value - lastRun;
if (diff < task.Frequency)
{
return(TaskResult.Skipped); // skip execution for now
}
break;
}
}
}
using (var m = new ProfileMarker("ExecuteTask"))
{
var taskScript = new ScriptBuilder()
.AllowGas(task.Owner, Address.Null, minimumFee, task.GasLimit)
.CallContract(task.ContextName, task.Method)
.SpendGas(task.Owner)
.EndScript();
transaction = new Transaction(this.Nexus.Name, this.Name, taskScript, block.Timestamp.Value + 1, "TASK");
VMObject vmResult;
if (ExecuteTransaction(-1, transaction, transaction.Script, block.Validator, block.Timestamp, changeSet, block.Notify, oracle, task, minimumFee, out vmResult, allowModify))
{
// merge transaction oracle data
oracle.MergeTxData();
var resultBytes = Serialization.Serialize(vmResult);
block.SetResultForHash(transaction.Hash, resultBytes);
var shouldStop = vmResult.AsBool();
return(shouldStop ? TaskResult.Halted : TaskResult.Running);
}
else
{
transaction = null;
return(TaskResult.Crashed);
}
}
}
private TaskResult ProcessPendingTask(Block block, OracleReader oracle, BigInteger minimumFee, StorageChangeSetContext changeSet, bool allowModify, ChainTask task, out Transaction transaction)
{
transaction = null;
BigInteger currentRun = GetTaskTimeFromBlock(task.Mode, block);
var taskKey = GetTaskKey(task.ID, "task_run");
if (task.Mode != TaskFrequencyMode.Always)
{
bool isFirstRun = !changeSet.Has(taskKey);
if (isFirstRun)
{
var taskBlockHash = GetBlockHashAtHeight(task.Height);
var taskBlock = GetBlockByHash(taskBlockHash);
BigInteger firstRun = GetTaskTimeFromBlock(task.Mode, taskBlock) + task.Delay;
if (currentRun < firstRun)
{
return(TaskResult.Skipped); // skip execution for now
}
}
else
{
BigInteger lastRun = isFirstRun ? changeSet.Get <BigInteger>(taskKey) : 0;
var diff = currentRun - lastRun;
if (diff < task.Frequency)
{
return(TaskResult.Skipped); // skip execution for now
}
}
}
else
{
currentRun = 0;
}
using (var m = new ProfileMarker("ExecuteTask"))
{
var taskScript = new ScriptBuilder()
.AllowGas(task.Owner, Address.Null, minimumFee, task.GasLimit)
.CallContract(task.ContextName, task.Method)
.SpendGas(task.Owner)
.EndScript();
transaction = new Transaction(this.Nexus.Name, this.Name, taskScript, block.Timestamp.Value + 1, "TASK");
VMObject vmResult;
if (ExecuteTransaction(-1, transaction, transaction.Script, block.Validator, block.Timestamp, changeSet, block.Notify, oracle, task, minimumFee, out vmResult, allowModify))
{
var resultBytes = Serialization.Serialize(vmResult);
block.SetResultForHash(transaction.Hash, resultBytes);
// update last_run value in storage
if (currentRun > 0)
{
changeSet.Put <BigInteger>(taskKey, currentRun);
}
var shouldStop = vmResult.AsBool();
return(shouldStop ? TaskResult.Halted : TaskResult.Running);
}
else
{
transaction = null;
return(TaskResult.Crashed);
}
}
}