Event batching for the Go SDK
How the Optimizely Feature Experimentation Go SDK uses the event processor to batch impressions and conversion events into a single payload before sending it to Optimizely.
The Optimizely Feature Experimentation Go SDK batches decision and conversion events into a single payload before sending it to Optimizely. This is achieved through an SDK component called the event processor.
Event batching has the advantage of reducing the number of outbound requests to Optimizely Feature Experimentation depending on how you define, configure, and use the event processor. It means less network traffic for the same number of Impression and conversion events tracked.
In the Go SDK, QueueingEventProcessor
provides implementation of the EventProcessor
interface and batches events. You can control batching based on two parameters:
- Batch size – Defines the number of events that are batched together before sending to Optimizely Feature Experimentation.
- Flush interval – Defines the amount of time after which any batched events should be sent to Optimizely Feature Experimentation.
An event consisting of the batched payload is sent as soon as the batch size reaches the specified limit or flush interval reaches the specified time limit. Batchcessor
options are described in more detail below.
Note
Event batching works with both out-of-the-box and custom event dispatchers.
The event batching process does not remove any personally identifiable information (PII) from events. Ensure that you are not sending any unnecessary PII to Optimizely.
Basic example
import optly "github.com/optimizely/go-sdk" // for v2: "github.com/optimizely/go-sdk/v2"
// the default client will have a BatchEventProcessor with the default options
optlyClient, err := optly.Client("SDK_KEY_HERE")
By default, batch size is 10 and flush interval is 30 seconds.
Advanced Example
To customize the event processor, you can use the client factory methods.
import (
"time"
"github.com/optimizely/go-sdk/pkg/client" // for v2: "github.com/optimizely/go-sdk/v2/pkg/client"
"github.com/optimizely/go-sdk/pkg/event" // for v2: "github.com/optimizely/go-sdk/v2/pkg/event"
"github.com/optimizely/go-sdk/pkg/utils" // for v2: "github.com/optimizely/go-sdk/v2/pkg/utils"
)
optimizelyFactory := &client.OptimizelyFactory{
SDKKey: "SDK_KEY",
}
// You can configure the batch size and flush interval
eventProcessor := event.NewBatchEventProcessor(
event.WithBatchSize(10),
event.WithFlushInterval(30 * time.Second),
)
optlyClient, err := optimizelyFactory.Client(
client.WithEventProcessor(eventProcessor),
)
Warning
The maximum payload size is 3.5 MB. Optimizely rejects requests with a 400 response code,
Bad Request Error
, if the batch payload exceeds this limit.The size limitation is because of the Optimizely Events API, which Feature Experimentation uses to send data to Optimizely.
The most common cause of a large payload size is a high batch size. If your payloads exceed the size limit, try configuring a smaller batch size.
BatchEventProcessor
BatchEventProcessor
is an implementation of EventProcessor
where events are batched. The class maintains a single consumer thread that pulls events off of an in-memory queue and buffers them for either a configured batch size or a maximum duration before the resulting LogEvent
is sent to the EventDispatcher
and NotificationCenter
.
The following properties can be used to customize the BatchEventProcessor
configuration.
Property | Default value | Description |
---|---|---|
event.EventDispatcher | NewQueueEventDispatcher | Used to dispatch event payload to Optimizely Feature Experimentation. |
event.BatchSize | 10 | The maximum number of events to batch before dispatching. Once this number is reached, all queued events are flushed and sent to Optimizely Feature Experimentation. |
event.FlushInterval | 30000 (30 Seconds) | Milliseconds to wait before batching and dispatching events. |
event.Q | NewInMemoryQueue | BlockingCollection that queues individual events to be batched and dispatched by the executor. |
event.MaxQueueSize | 1000 | The maximum number of events that can be queued. |
For more information, see Initialize the Go SDK.
Side Effects
The table lists other Optimizely Feature Experimentation functionality that may be triggered by using this method.
Functionality | Description |
---|---|
LogEvent | Whenever the event processor produces a batch of events, a LogEvent object will be created using the event factory.It contains batch of conversion and decision events. This object will be dispatched using the provided event dispatcher and also it will be sent to the notification subscribers |
Notification Listeners | Flush invokes the LOGEVENT notification listener if this listener is subscribed to. |
Register and Unregister a LogEvent
listener
LogEvent
listenerThe example code below shows how to add and remove a LogEvent
notification listener.
import (
"fmt"
"github.com/optimizely/go-sdk/pkg/client" // for v2: "github.com/optimizely/go-sdk/v2/pkg/client"
"github.com/optimizely/go-sdk/pkg/event" // for v2: "github.com/optimizely/go-sdk/v2/pkg/event"
)
// Callback for log event notification
callback := func(notification event.LogEvent) {
// URL to dispatch log event to
fmt.Print(notification.EndPoint)
// Batched event
fmt.Print(notification.Event)
}
optimizelyFactory := &client.OptimizelyFactory{
SDKKey: "SDK_KEY",
}
optimizelyClient, err := optimizelyFactory.Client()
if err != nil {
// handle error
}
// Add callback for logEvent notification
id, err := optimizelyClient.EventProcessor.(*event.BatchEventProcessor).OnEventDispatch(callback)
if err != nil {
// handle error
}
// Remove callback for logEvent notification
err = optimizelyClient.EventProcessor.(*event.BatchEventProcessor).RemoveOnEventDispatch(id)
LogEvent
LogEvent
LogEvent
object gets created using factory
. It represents the batch of decision and conversion events we send to the Optimizely Feature Experimentation backend.
Object | Type | Description |
---|---|---|
EndPoint Required (non null) | String | URL to dispatch log event to. |
Event Required | event.Batch | Contains all the information regarding every event which is batched. Including list of visitors which contains UserEvent . |
Close Optimizely Feature Experimentation on application exit
If you enable event batching, you must call the Close method (optimizelyClient.Close()
) before exiting. This ensures that queued events are flushed as soon as possible to avoid data loss.
Warning
Because the Optimizely Feature Experimentation client maintains a buffer of queued events, you must call
Close()
on the Optimizely Feature Experimentation instance before shutting down your application or whenever dereferencing the instance.
Method | Description |
---|---|
Close() | Stops all executor threads and flushes the event queue. This method will also stop any scheduledExecutorService that is running for the data-file manager. |
Updated 10 months ago