Querying Events

You can query events with the GetEventsForHeightRange function:

import "github.com/onflow/flow-go-sdk/client"

blocks, err := c.GetEventsForHeightRange(ctx, client.EventRangeQuery{
    Type:       "flow.AccountCreated",
    StartHeight: 10,
    EndHeight:   15,
})
if err != nil {
    panic("failed to query events")
}

Event Query Format

An event query includes the following fields:

Type

The event type to filter by. Event types are namespaced by the account and contract in which they are declared.

For example, a Transfer event that was defined in the Token contract deployed at account 0x55555555555555555555 will have a type of A.0x55555555555555555555.Token.Transfer.

Read the language documentation for more information on how to define and emit events in Cadence.

StartHeight, EndHeight

The blocks to filter by. Events will be returned from blocks in the range StartHeight to EndHeight, inclusive.

Event Results

The GetEventsForHeightRange function returns events grouped by block. Each block contains a list of events matching the query in order of execution.

for _, block := range blocks {
    fmt.Printf("Events for block %s:\n", block.BlockID)
    for _, event := range block.Events {
        fmt.Printf(" - %s", event)
    }
}