dongrong3171
dongrong3171
2016-09-20 12:30

进入lang While循环

已采纳
  • I want to extract all the autoscaling groups from AWS
  • AWS provides response in multiple pages with NextToken pointing to next page. So need keep looking for NextToken and pull the group names
  • If there is no NextToken, then quit.

In python, I do:

import boto3
import pprint

session = boto3.session.Session(region_name='us-west-2')
client = session.client('autoscaling')

resp = client.describe_auto_scaling_groups()
pprint.pprint(resp)

while 'NextToken' in resp:
    resp = client.describe_auto_scaling_groups(NextToken=resp['NextToken'])          
    pprint.pprint(resp)

I followed similar logic in and came up with below code:

package main

import (
    "fmt"
    "github.com/aws/aws-sdk-go/aws"
    "github.com/aws/aws-sdk-go/aws/session"
    "github.com/aws/aws-sdk-go/service/autoscaling"
)

func main() {
    sess, err := session.NewSession(&aws.Config{Region: aws.String("us-west-2")})

    if err != nil {
        fmt.Println("Failed to create session: ", sess)
        return
    }

    svc := autoscaling.New(sess)
    params := &autoscaling.DescribeAutoScalingGroupsInput{}
    resp, err := svc.DescribeAutoScalingGroups(params)

    if err != nil {
        fmt.Println("Something Went wrong")
        return
    }

    fmt.Println(resp)

    for {
        if resp.NextToken == nil {
            fmt.Println("No more pages left")
            break
        }

        params := &autoscaling.DescribeAutoScalingGroupsInput{
            NextToken: aws.String(*resp.NextToken),
        }
        resp, err := svc.DescribeAutoScalingGroups(params)

        if err != nil {
            fmt.Println("Something Went wrong")
            return
        }

        fmt.Println(resp)
    }
}

QUESTION: My code goes to the 2nd page and then keep looping over the same 2nd page. It does not proceed to 3rd page (when there is NextToken in resp) or it does not quit (when there is no NextToken in resp).

Seeking help on my code. I am learning

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1条回答

  • doulu8537 doulu8537 5年前

    Your inner resp seems to shadow your original resp. Try this inside the inner for loop (:= replaced with =):

    resp, err = svc.DescribeAutoScalingGroups(params)
    
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