DynamoDB list all backups using AWS GoLang SDK - amazon-web-services

Question

Based on the example given in the link blow on API Operation Pagination without Callbacks
https://aws.amazon.com/blogs/developer/context-pattern-added-to-the-aws-sdk-for-go/
I am trying to list all the Backups in dynamodb. But it seems like pagination is not working and it is just retrieving first page and not going to next page
package main
import (
"context"
"fmt"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/request"
"github.com/aws/aws-sdk-go/aws/session"
"github.com/aws/aws-sdk-go/service/dynamodb"
)
func main() {
sess, sessErr := session.NewSession()
if sessErr != nil {
fmt.Println(sessErr)
fmt.Println("Cound not initilize session..returning..")
return
}
// Create DynamoDB client
dynamodbSvc := dynamodb.New(sess)
params := dynamodb.ListBackupsInput{}
ctx := context.Background()
p := request.Pagination{
NewRequest: func() (*request.Request, error) {
req, _ := dynamodbSvc.ListBackupsRequest(&params)
req.SetContext(ctx)
return req, nil
},
}
for p.Next() {
page := p.Page().(*dynamodb.ListBackupsOutput)
fmt.Println("Received", len(page.BackupSummaries), "objects in page")
for _, obj := range page.BackupSummaries {
fmt.Println(aws.StringValue(obj.BackupName))
}
}
//return p.Err()
} //end of main

Answer 1

Its a bit late but I'll just put it here in case I can help somebody.
Example:
var exclusiveStartARN *string
var backups []*dynamodb.BackupSummary
for {
backup, err := svc.ListBackups(&dynamodb.ListBackupsInput{
ExclusiveStartBackupArn:exclusiveStartARN,
})
if err != nil {
fmt.Println(err)
os.Exit(1)
}
backups = append(backups, backup.BackupSummaries...)
if backup.LastEvaluatedBackupArn != nil {
exclusiveStartARN = backup.LastEvaluatedBackupArn
//max 5 times a second so we dont hit the limit
time.Sleep(200 * time.Millisecond)
continue
}
break
}
fmt.Println(len(backups))
Explaination:
The way that pagination is done is via ExclusiveStartBackupArn in the ListBackupsRequest. The ListBackupsResponse returns LastEvaluatedBackupArn if there are more pages, or nil if its the last/only page.

Answer 2

It could be that you're smashing into the API a bit with your usage
You can call ListBackups a maximum of 5 times per second.
What is the value of p.HasNextPage() in your p.Next() loop?