WithStreaming Example

This example demonstrates how to use TrueBlocks SDK's streaming capabilities to process blockchain data efficiently.

What it does

The example shows how to stream various data types (blocks, transactions, logs, ABIs, etc.) using channels to process large amounts of blockchain data asynchronously.

Available Streaming Examples

Several examples are implemented:

• TestStreamBlocks: Stream block data
• TestStreamExport: Stream transactions with timeout cancellation
• TestStreamNames: Stream name data
• TestStreamProgress: Track progress with a progress bar
• TestStreamAbis: Stream and process contract ABIs

TestStreamExport Example

The export example demonstrates how to:

1. Stream transactions for a specific address (Uniswap V3 Factory)
2. Process the transactions as they arrive
3. Cancel the streaming operation after a timeout

// Create options with a streaming context
opts := sdk.ExportOptions{
    Addrs:     []string{"0x1f98431c8ad98523631ae4a59f267346ea31f984"},
    Unripe:    true,  // to the head of the chain
    RenderCtx: output.NewStreamingContext(),
}

// Set up a cancellation after 3 seconds
go func() {
    time.Sleep(3 * time.Second)
    opts.RenderCtx.Cancel()  // This gracefully stops the streaming
}()

// Process the data as it streams in
go func() {
    for {
        select {
        case model := <-opts.RenderCtx.ModelChan:
            if tx, ok := model.(*types.Transaction); ok {
                fmt.Printf("%d\t%d\n", tx.BlockNumber, tx.TransactionIndex)
            }
        case err := <-opts.RenderCtx.ErrorChan:
            // Handle errors
        }
    }
}()

// Start the stream
opts.Export()

This pattern is useful when you need to process large amounts of data without loading everything into memory at once.

Running the example

go build -o out main.go
./out

By default, TestStreamExport runs, but you can uncomment other examples in main.go.

Note: If you remove this example, you will need to also remove the reference to it from ./go.work in the root folder.