I am trying to list the Items and other values from the AWS Dynamodb table(DDNS), However, if only look for InstnaceId then I am able to get the entire list of my instances, however i want to get few more selective values from the table which is a nested json, I am not able to figure about how to do that.

Below is Successful while only looking for InstanceId:

(awscliv2) $ aws dynamodb scan --table-name DDNS --query "Items[*].{InstanceId:InstanceId}" --region us-west-2
[
    {
        "InstanceId": {
            "S": "i-03dd05693e4y43b9b"
        }
    },
    {
        "InstanceId": {
            "S": "i-07b4a8yr38d89faf1"
        }
    },
    {
        "InstanceId": {
            "S": "i-029340cb56eeae8a1"
        }
    },

View From AWS DynamoDB console:

Below I could see, there are two columns

• one is InstanceId
• another is InstanceAttributes and all these values nested in this only

Below is just what the nested output looks like:

• precisely from the below I want to list down values like InstanceId, RootDeviceName, ImageId and InstanceType etc.
• I am failing to get there to list them.

apologies, i am adding pics here Just to address my issues. any help will be very much appreciated.

CodePudding user response：

You Should Probably try below which is working for me on my test.

#!/bin/bash
# List the DynamoDB contents from table
aws dynamodb scan --table-name DDNS --region us-west-2 \
  --query 'Items[*].{ "Instance IP" :    InstanceAttributes.M.Reservations.L[*].M.Instances.L[*].M.PrivateIpAddress.S[]|[0],
                      "Instance TYPE":   InstanceAttributes.M.Reservations.L[*].M.Instances.L[*].M.InstanceType.S[]|[0],
                      "Instance ID":     InstanceAttributes.M.Reservations.L[*].M.Instances.L[*].M.InstanceId.S[]|[0],
                      "Image ID":        InstanceAttributes.M.Reservations.L[*].M.Instances.L[*].M.ImageId.S[]|[0],
                      "Root Device":     InstanceAttributes.M.Reservations.L[*].M.Instances.L[*].M.RootDeviceName.S[]|[0] }' \
  --output table \
  --no-cli-pager

Result:

----------------------------------------------------------------------------------------------------
|                                               Scan                                               |
 ------------------------ ---------------------- --------------- ------------------ --------------- 
|        Image ID        |     Instance ID      |  Instance IP  |  Instance TYPE   |  Root Device  |
 ------------------------ ---------------------- --------------- ------------------ --------------- 
|  ami-0660c6f78888h2dcad |  i-03dd05693e2fe3b9b |  10.0.10.200 |  r6i.large       |  /dev/sda1    |
|  ami-06811f95599jjh8126 |  i-07b4a16b44d89faf1 |  10.0.10.100 |  r6i.large       |  /dev/sda1    |
|  ami-0660c6f7c9dhhg6cad |  i-025830cb11llae8a1 |  10.0.10.110 |  r6i.large       |  /dev/sda1    |
|  ami-087945320da3908tf3 |  i-0c3e05430176nm5db |  10.0.10.111 |  r6i.large       |  /dev/sda1    |
----------------------------------------------------------------------------------------------------