Flow creation

The data flow corresponds to the route the specific action takes from the pool to the data consumer contract. In Quex, the general flow structure is the following

struct Flow {
    uint256 gasLimit;
    uint256 actionId;
    address pool;
    address consumer;
    bytes4 callback;
}

Here the gasLimit is the gas limit for the callback function on the consumer contract. Once created, the flow will be used every time your contract needs to consume the data corresponding to the actionId from the oracle pool. Note that for request-based processing, the gasLimit contributes to amount which must be attached to the subsequent requests. All the data is verified by Quex Core prior to the delivery, and the callback on consumer contract is invoked with the designated gasLimit.

The flow can be created on Quex Core with createFlow(Flow memory flow) call which returns flowId for later reference. This id can also be recorded from the FlowAdded(uint256 flowId) event emitted at flow creation.