Using jq to parse json output of AWS CLI

Question

I would like to use jq (http://stedolan.github.io/jq/) to parse the json output from aws elb describe-load-balancers and return the name and AZs only where AvailabilityZones contains a specific value.

Here is partial redacted json representing the source output:

{
  "LoadBalancerDescriptions": [
    {
    {
      "AvailabilityZones": [
        "us-east-1b",
        "us-east-1c",
        "us-east-1d"
      ],
      "CanonicalHostedZoneName": "example.us-east-1.elb.amazonaws.com",

I have only been able to get this to work when specifiying the full list of values for the AvailabilityZones key.

$ aws elb describe-load-balancers --region us-east-1 |jq '.LoadBalancerDescriptions[] | select(.AvailabilityZones == ["us-east-1b", "us-east-1c", "us-east-1d"]) | .CanonicalHostedZoneName, .AvailabilityZones'

The above works, but I want to just select if it contains a value for "us-east-1b", regardless of the other values.

I guess a more general way to ask this is how do I us jq to test a key containing multiple values for equality of just one of those values? — cp_clegg
– cp_clegg, Commented Sep 13, 2013 at 23:27
i want to parse the output of aws ec2 describe instances. can you help — user3086014
– user3086014, Commented Mar 28, 2014 at 5:09

konsolebox · Accepted Answer · 2013-09-16 21:12:40Z

5

Perhaps this could work:

aws elb describe-load-balancers --region us-east-1 | jq '.LoadBalancerDescriptions[] | select((.AvailabilityZones[] | select(. == "us-east-1b")) == "us-east-1b") | .CanonicalHostedZoneName, .AvailabilityZones'

I actually tested with an input like this:

{
  "LoadBalancerDescriptions": [
    {
      "AvailabilityZones": [
        "us-east-1b",
        "us-east-1c",
        "us-east-1d"
      ]
    }
  ]
}

And ran this command:

jq '.LoadBalancerDescriptions[] | select((.AvailabilityZones[] | select(. == "us-east-1b")) == "us-east-1b")' input_file

Then I got:

{
  "AvailabilityZones": [
    "us-east-1b",
    "us-east-1c",
    "us-east-1d"
  ]
}

Another for input:

{
  "LoadBalancerDescriptions": [
    {
      "AvailabilityZones": [
        "us-east-1b",
        "us-east-1c",
        "us-east-1d"
      ]
    },
    {
      "AvailabilityZones": [
        "us-east-1b",
        "us-east-1c"
      ]
    },
    {
      "AvailabilityZones": [
        "us-east-1d"
      ]
    }
  ]
}

Output:

{
  "AvailabilityZones": [
    "us-east-1b",
    "us-east-1c",
    "us-east-1d"
  ]
}
{
  "AvailabilityZones": [
    "us-east-1b",
    "us-east-1c"
  ]
}

You probably could use the concept to validate if a key representing an array contains an element like it.

edited Sep 16, 2013 at 21:12

answered Sep 13, 2013 at 23:59

konsolebox

76.3k13 gold badges110 silver badges114 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

cp_clegg Over a year ago

Unfortunately, I don't think that works. Try that on an input_file that has three groups of AvailabilityZones, one like what you used, plus one with just us-east-1b and us-east-1c, and then a third with only us-east-1d. I would expect the query to return the first two AvailabiltyZones but not the third however the query only returns the first.

konsolebox Over a year ago

@user2778073 I did make the solution with that intention. Testing it again returns two results as you expect.

cp_clegg Over a year ago

You are completely right. Thanks you for taking the time to clarify but it was a mistake on my part with the json structure in my test input_file.

Collectives™ on Stack Overflow

Using jq to parse json output of AWS CLI

1 Answer 1

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related