Querying Blocks

You can use the GetLatestBlock method to fetch the latest sealed or unsealed block:

// fetch the latest sealed block
isSealed := true
latestBlock, err := c.GetLatestBlock(ctx, isSealed)
if err != nil {
    panic("failed to fetch latest sealed block")
}

// fetch the latest unsealed block
isSealed := false
latestBlock, err := c.GetLatestBlock(ctx, isSealed)
if err != nil {
    panic("failed to fetch latest unsealed block")
}

A block contains the following fields:

• ID - The ID (hash) of the block.
• ParentBlockID - The ID of the previous block in the chain.
• Height - The height of the block in the chain.
• CollectionGuarantees - The list of collections included in the block.

Executing a Script

You can use the ExecuteScriptAtLatestBlock method to execute a read-only script against the latest sealed execution state.

This functionality can be used to read state from the blockchain.

Scripts must be in the following form:

• A single main function with a single return value

This is an example of a valid script:

fun main(): Int { return 1 }

import "github.com/onflow/cadence"

script := []byte("fun main(): Int { return 1 }")

value, err := c.ExecuteScript(ctx, script)
if err != nil {
    panic("failed to execute script")
}

ID := value.(cadence.Int)

// convert to Go int type
myID := ID.Int()