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jq
misc
json, jq
Jul 14, 2022
parse json with jq
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misc_jq.html
Misc

jq

=====

data

$ cat /tmp/data
{
    "Subnets": [
        {
            "AvailabilityZone": "us-east-1a",
            "Tags": [
                {
                    "Value": "DEV",
                    "Key": "Env"
                },
                {
                    "Value": "AccountBase",
                    "Key": "aws:cloudformation:stack-name"
                },
                {
                    "Value": "PrivateSubnet1a",
                    "Key": "aws:cloudformation:logical-id"
                },
                {
                    "Value": "Systems",
                    "Key": "Owner"
                },
                {
                    "Value": "PrivateSubnet1a",
                    "Key": "Name"
                }
            ],
            "AvailableIpAddressCount": 214,
            "DefaultForAz": false,
            "Ipv6CidrBlockAssociationSet": [],
            "State": "available",
            "MapPublicIpOnLaunch": false,
            "SubnetId": "subnet-xxxxxx",
            "CidrBlock": "10.1.2.0/24",
            "AssignIpv6AddressOnCreation": false
        },
        {
            "AvailabilityZone": "us-east-1a",
            "Tags": [
                {
                    "Value": "Systems",
                    "Key": "Owner"
                },
                {
                    "Value": "AccountBase",
                    "Key": "aws:cloudformation:stack-name"
                },
                {
                    "Value": "PublicSubnet1a",
                    "Key": "aws:cloudformation:logical-id"
                },
                {
                    "Value": "DEV",
                    "Key": "Env"
                }
            ],
            "AvailableIpAddressCount": 250,
            "DefaultForAz": false,
            "Ipv6CidrBlockAssociationSet": [],
            "State": "available",
            "MapPublicIpOnLaunch": false,
            "SubnetId": "subnet-yyyyyy",
            "CidrBlock": "10.1.0.0/24",
            "AssignIpv6AddressOnCreation": false
        }
    ]
}

Options

-S sort keys

$ cat /tmp/jq-data | jq -r -S '.Subnets[0]'
{
  "AssignIpv6AddressOnCreation": false,
  "AvailabilityZone": "us-east-1a",
  "AvailableIpAddressCount": 214,
  "CidrBlock": "10.1.2.0/24",
  "DefaultForAz": false,
  "Ipv6CidrBlockAssociationSet": [],
  "MapPublicIpOnLaunch": false,
  "State": "available",
  "SubnetId": "subnet-xxxxxx",
  "Tags": [
    {
      "Key": "Env",
      "Value": "DEV"
    },
    {
      "Key": "aws:cloudformation:stack-name",
      "Value": "AccountBase"
    },
    {
      "Key": "aws:cloudformation:logical-id",
      "Value": "PrivateSubnet1a"
    },
    {
      "Key": "Owner",
      "Value": "Systems"
    },
    {
      "Key": "Name",
      "Value": "PrivateSubnet1a"
    }
  ]
}

-c compact output

$ cat /tmp/jq-data | jq -c
{"Subnets":[{"AvailabilityZone":"us-east-1a","Tags":[{"Value":"DEV","Key":"Env"},{"Value":"AccountBase","Key":"aws:cloudformation:stack-name"},{"Value":"PrivateSubnet1a","Key":"aws:cloudformation:logical-id"},{"Value":"Systems","Key":"Owner"},{"Value":"PrivateSubnet1a","Key":"Name"}],"AvailableIpAddressCount":214,"DefaultForAz":false,"Ipv6CidrBlockAssociationSet":[],"State":"available","MapPublicIpOnLaunch":false,"SubnetId":"subnet-xxxxxx","CidrBlock":"10.1.2.0/24","AssignIpv6AddressOnCreation":false},{"AvailabilityZone":"us-east-1a","Tags":[{"Value":"Systems","Key":"Owner"},{"Value":"AccountBase","Key":"aws:cloudformation:stack-name"},{"Value":"PublicSubnet1a","Key":"aws:cloudformation:logical-id"},{"Value":"DEV","Key":"Env"}],"AvailableIpAddressCount":250,"DefaultForAz":false,"Ipv6CidrBlockAssociationSet":[],"State":"available","MapPublicIpOnLaunch":false,"SubnetId":"subnet-yyyyyy","CidrBlock":"10.1.0.0/24","AssignIpv6AddressOnCreation":false}]}

-f read filter from file

$ cat /tmp/filter
.Subnets[].AvailabilityZone

$ cat /tmp/jq-data | jq -r -f /tmp/filter
us-east-1a
us-east-1a

--arg / --argjson pass parameters from bash

$ test_cidr='10.1.0.*'

$ jq -r --arg cidr "${test_cidr}" '.Subnets[] | {cidr: .CidrBlock} | select(.cidr | test($cidr))' /tmp/data
{
  "cidr": "10.1.0.0/24"
}

parameter as an integer

$ avaiable_ips_threshhold=220

$ jq -r --argjson ip_threshhold "${avaiable_ips_threshhold}" '.Subnets[] | {subnetid: .SubnetId, AvailableIp: .AvailableIpAddressCount} | select(.AvailableIp > $ip_threshhold)' /tmp/data
{
  "subnetid": "subnet-yyyyyy",
  "AvailableIp": 250
}

$ jq -r --arg ip_threshhold "${avaiable_ips_threshhold}" '.Subnets[] | {subnetid: .SubnetId, AvailableIp: .AvailableIpAddressCount} | select(.AvailableIp > ($ip_threshhold | tonumber))' /tmp/jq-data
{
  "subnetid": "subnet-yyyyyy",
  "AvailableIp": 250
}

--slrupfile reads JSON from file and binds to a global variable

$ cat /tmp/filter | jq .
{
  "avaiable_ips_threshhold": 220
}

$ jq -r --slurpfile var /tmp/filter '$var' /tmp/jq-data
[
  {
    "avaiable_ips_threshhold": 220
  }
]

$ jq -r --slurpfile var /tmp/filter '.Subnets[] | {subnetid: .SubnetId, AvailableIp: .AvailableIpAddressCount} | select(.AvailableIp > $var[0].avaiable_ips_threshhold)' /tmp/jq-data
{
  "subnetid": "subnet-yyyyyy",
  "AvailableIp": 250
}

Types and Values

.. Recursive Descent

Built-in Functions

length

gets the length of various different types of value

$ cat /tmp/data | jq '.Subnets | length'
2

Count elements based on some specifict conditions

$ jq -r '.Subnets[] | select(.State == "available") | length' /tmp/data
10
10

$ jq -r '[.Subnets[] | select(.State == "available")] | length' /tmp/data
2

keys / keys_unsorted

returns its keys in an array

$ cat /tmp/data | jq '. | keys[]'
"Subnets"

$ cat /tmp/data | jq '.Subnets[0] | keys_unsorted '
[
  "AvailabilityZone",
  "Tags",
  "AvailableIpAddressCount",
  "DefaultForAz",
  "Ipv6CidrBlockAssociationSet",
  "State",
  "MapPublicIpOnLaunch",
  "SubnetId",
  "CidrBlock",
  "AssignIpv6AddressOnCreation"
]

$ cat /tmp/data | jq '.Subnets | keys[]'
0
1

has(key)

returns whether the input object has the given key / in returns the input key is in the given object, or the input index corresponds to an element in the given array

$ cat /tmp/data | jq 'has("Subnets")'
true

$ cat /tmp/data | jq '. | keys[] | in({"Subnets": 1})'
true

$ cat /tmp/data | jq '.Subnets | keys[]'
0
1

$ cat /tmp/data | jq '[2] | keys[]'
0

$ cat /tmp/data | jq '.Subnets | keys[] | in([2])'
true
false

# given array '[2]' has only one index: 0

map(x) / map_values(x)

apply filter x to each element of the input array

$ cat /tmp/data | jq '.Subnets | keys'
[
  0,
  1
]

$ cat /tmp/data | jq '.Subnets | keys | map(.+1)'
[
  1,
  2
]

path(path_expression)

returns array representations of the given path expression in .. The outputs are arrays of strings (object keys) and/or numbers (array indices).

$ cat /tmp/data | jq '.Subnets[0].SubnetId'
"subnet-xxxxxx"

$ cat /tmp/data | jq 'path(.Subnets[0].SubnetId)'
[
  "Subnets",
  0,
  "SubnetId"
]

del(path_expression)

removes a key and its corresponding value

$ cat /tmp/data | jq '.Subnets[] | del(.Tags)'
{
  "AvailabilityZone": "us-east-1a",
  "AvailableIpAddressCount": 214,
  "DefaultForAz": false,
  "Ipv6CidrBlockAssociationSet": [],
  "State": "available",
  "MapPublicIpOnLaunch": false,
  "SubnetId": "subnet-xxxxxx",
  "CidrBlock": "10.1.2.0/24",
  "AssignIpv6AddressOnCreation": false
}
{
  "AvailabilityZone": "us-east-1a",
  "AvailableIpAddressCount": 250,
  "DefaultForAz": false,
  "Ipv6CidrBlockAssociationSet": [],
  "State": "available",
  "MapPublicIpOnLaunch": false,
  "SubnetId": "subnet-yyyyyy",
  "CidrBlock": "10.1.0.0/24",
  "AssignIpv6AddressOnCreation": false
}

getpath(PATHS)

returns the values in of each PATHS.

$ cat /tmp/data| jq 'getpath(["Subnets", 0, "AvailableIpAddressCount"], ["Subnets", 1, "AvailableIpAddressCount"])'
214
250

setpath(PATHS; VALUE)

set VALUE for PATHS.

$ cat /tmp/data| jq 'setpath(["Subnets", 0, "AvailableIpAddressCount"]; 0) | .Subnets[].AvailableIpAddressCount'
0
250

to_entries, from_entries, with_entries

to_entries converts an array to {"key": k, "value": v}.
from_entries converts on the opposite way.
with_entries(filter) is same as to_entries | map(filter) | from_entries

$ cat /tmp/data | jq '.Subnets[].Tags | from_entries'
{
  "Env": "DEV",
  "aws:cloudformation:stack-name": "AccountBase",
  "aws:cloudformation:logical-id": "PrivateSubnet1a",
  "Owner": "Systems",
  "Name": "PrivateSubnet1a"
}
{
  "Owner": "Systems",
  "aws:cloudformation:stack-name": "AccountBase",
  "aws:cloudformation:logical-id": "PublicSubnet1a",
  "Env": "DEV"
}

$ cat /tmp/data | jq '.Subnets[] | to_entries | map(select(.key == "AvailableIpAddressCount"))'
[
  {
    "key": "AvailableIpAddressCount",
    "value": 214
  }
]
[
  {
    "key": "AvailableIpAddressCount",
    "value": 250
  }
]

$ cat /tmp/data | jq '.Subnets[] | with_entries(select(.key == "AvailableIpAddressCount"))'
{
  "AvailableIpAddressCount": 214
}
{
  "AvailableIpAddressCount": 250
}

select(boolean_expression)

produces its input unchanged if it returns true for that input, and produces no output otherwise.

arrays, objects, iterables, booleans, numbers, normals, finites, strings, nulls, values, scalars

selects above objects as result

paths

outputs the paths to all the elements, which is similar as path(..) paths(filter) output the paths which value match filter

$ cat /tmp/data | jq 'paths(select(.Key? == "Env"))'
[
  "Subnets",
  0,
  "Tags",
  0
]
[
  "Subnets",
  1,
  "Tags",
  3
]

$ cat /tmp/data | jq 'getpath(["Subnets", 0, "Tags", 0])'
{
  "Value": "DEV",
  "Key": "Env"
}

$ cat /tmp/data | jq 'getpath(["Subnets", 1, "Tags", 3])'
{
  "Value": "DEV",
  "Key": "Env"
}

add

add all elements of input array

$ cat /tmp/data | jq '[.Subnets[].AvailableIpAddressCount] | add'
464

$ cat /tmp/data | jq '[.Subnets[].AvailabilityZone] | add'
"us-east-1aus-east-1a"

$ cat /tmp/data | jq '[.Subnets[] | .AvailabilityZone, .AvailableIpAddressCount | tostring] | add'
"us-east-1a214us-east-1a250"

any / all / any(condition) / all(condition)

any takes an array of boolean values, and returns true if any of them are true
all takes an array of boolean values, and returns true if all of them are true
any(condition) applies condition to all elements of given array, and returns true if any of them are true
all(condition) applies condition to all elements of given array, and returns true if all of them are true

$ cat /tmp/data | jq '[.Subnets[0].AvailableIpAddressCount > 220, .Subnets[1].AvailableIpAddressCount > 220] | any '
true

$ cat /tmp/data | jq '[.Subnets[].AvailableIpAddressCount] | any(. > 220)'
true

$ cat /tmp/data | jq '[.Subnets[].AvailableIpAddressCount] | all(. > 220)'
false

range(upto) / range(from; upto) / range(from; to; by)

generates a range of numbers from until upto with step by

tonumber / tostring

convert input to number or string

type

returns the type of inputs

sort / sort_by(path_expression)

sort an array with following order:

  • null
  • false
  • true
  • nubmers
  • strings (alphabetical order)
  • array (lexical order)
  • object
    or sort the array based on value of path_expression
$ jq -r '[.Subnets[].AvailableIpAddressCount]' /tmp/data
[
  250,
  214
]

$ jq -r '[.Subnets[].AvailableIpAddressCount] | sort' /tmp/data
[
  214,
  250
]

group_by(path_expression)

takes as input an array, groups the elements having the same path_expression field value into separate arrays, and produces all of these arrays as elements of a larger array.

$ echo '[{"a": 1}, {"b": 2}, {"a": 1}, {"a": 2}]' | jq 'group_by(.a)'
[
  [
    {
      "b": 2
    }
  ],
  [
    {
      "a": 1
    },
    {
      "a": 1
    }
  ],
  [
    {
      "a": 2
    }
  ]
]

min / max / min_by(path_exp) / max_by(path_exp)

get min or max element of input array

$ cat /tmp/data | jq '[.Subnets[].AvailableIpAddressCount] | min '
214

$ cat /tmp/data | jq '[.Subnets[].AvailableIpAddressCount] | max '
250

$ cat /tmp/data | jq '.Subnets | min_by(.AvailableIpAddressCount)'
{
  "AvailabilityZone": "us-east-1a",
  "Tags": [
    {
      "Value": "DEV",
      "Key": "Env"
    },
    {
      "Value": "AccountBase",
      "Key": "aws:cloudformation:stack-name"
    },
    {
      "Value": "PrivateSubnet1a",
      "Key": "aws:cloudformation:logical-id"
    },
    {
      "Value": "Systems",
      "Key": "Owner"
    },
    {
      "Value": "PrivateSubnet1a",
      "Key": "Name"
    }
  ],
  "AvailableIpAddressCount": 214,
  "DefaultForAz": false,
  "Ipv6CidrBlockAssociationSet": [],
  "State": "available",
  "MapPublicIpOnLaunch": false,
  "SubnetId": "subnet-xxxxxx",
  "CidrBlock": "10.1.2.0/24",
  "AssignIpv6AddressOnCreation": false
}

$ cat /tmp/data | jq '.Subnets | max_by(.AvailableIpAddressCount)'
{
  "AvailabilityZone": "us-east-1a",
  "Tags": [
    {
      "Value": "Systems",
      "Key": "Owner"
    },
    {
      "Value": "AccountBase",
      "Key": "aws:cloudformation:stack-name"
    },
    {
      "Value": "PublicSubnet1a",
      "Key": "aws:cloudformation:logical-id"
    },
    {
      "Value": "DEV",
      "Key": "Env"
    }
  ],
  "AvailableIpAddressCount": 250,
  "DefaultForAz": false,
  "Ipv6CidrBlockAssociationSet": [],
  "State": "available",
  "MapPublicIpOnLaunch": false,
  "SubnetId": "subnet-yyyyyy",
  "CidrBlock": "10.1.0.0/24",
  "AssignIpv6AddressOnCreation": false
}

unique / unique_by(path_exp)

produces an array without duplicated elements from input array.

$ cat /tmp/data | jq '[.Subnets[].Tags[]] | unique'
[
  {
    "Value": "DEV",
    "Key": "Env"
  },
  {
    "Value": "PrivateSubnet1a",
    "Key": "Name"
  },
  {
    "Value": "Systems",
    "Key": "Owner"
  },
  {
    "Value": "PrivateSubnet1a",
    "Key": "aws:cloudformation:logical-id"
  },
  {
    "Value": "PublicSubnet1a",
    "Key": "aws:cloudformation:logical-id"
  },
  {
    "Value": "AccountBase",
    "Key": "aws:cloudformation:stack-name"
  }
]

$ cat /tmp/data | jq '[.Subnets[].Tags[]] | unique_by(.Key)'
[
  {
    "Value": "DEV",
    "Key": "Env"
  },
  {
    "Value": "PrivateSubnet1a",
    "Key": "Name"
  },
  {
    "Value": "Systems",
    "Key": "Owner"
  },
  {
    "Value": "PublicSubnet1a",
    "Key": "aws:cloudformation:logical-id"
  },
  {
    "Value": "AccountBase",
    "Key": "aws:cloudformation:stack-name"
  }
]

reverse

reverses an input array

contains(element)

evaluate the element was included in input

$ cat /tmp/data | jq '.Subnets[].AvailabilityZone | contains("east")'
true
true

$ cat /tmp/data | jq '.Subnets[].Tags[] | contains({"Key": "Env"})'
false
false
false
true
true
false
false
false
false

indices(s)

returns index of s or value of key s

$ echo '[{"a": 1}, {"b": 2}, {"a": 1}, {"a": 2}]' | jq '.[] | indices("a")'
1
null
1
2

$ echo '[{"a": 1}, {"b": 2}, {"a": 1}, {"a": 2}]' | jq 'indices({"a": 2})'
[
  3
]

index(s) / rindex(s)

returns the first index of s or last index of s

$ echo '[{"a": 1}, {"b": 2}, {"a": 1}, {"a": 2}]' | jq 'index({"a": 1})'
0

$ echo '[{"a": 1}, {"b": 2}, {"a": 1}, {"a": 2}]' | jq 'rindex({"a": 1})'
2

inside(s)

inversed version of contains

startswith(str) / endswith(str)

$ cat /tmp/data | jq '[.Subnets[0].Tags[] | {key: .Key, value: .Value}] | from_entries[] '
"Systems"
"AccountBase"
"PublicSubnet1a"
"DEV"

$ cat /tmp/data | jq '[.Subnets[0].Tags[] | {key: .Key, value: .Value}] | from_entries[] | startswith("Sys")'
true
false
false
false

$ cat /tmp/data | jq '[.Subnets[0].Tags[] | {key: .Key, value: .Value}] | from_entries[] | endswith("Base")'
false
true
false
false

combinations / combinations(n)

outputs all combinations of the elements of input arrays. With n means to output n repetitions of input array

$ echo '[[1, 2], [3, 4]]' | jq 'combinations'
[
  1,
  3
]
[
  1,
  4
]
[
  2,
  3
]
[
  2,
  4
]

$ echo '[[1, 2], [3, 4]]' | jq 'combinations(2)'
[
  [
    1,
    2
  ],
  [
    1,
    2
  ]
]
[
  [
    1,
    2
  ],
  [
    3,
    4
  ]
]
[
  [
    3,
    4
  ],
  [
    1,
    2
  ]
]
[
  [
    3,
    4
  ],
  [
    3,
    4
  ]
]

ltrimstr(str) / rtrimstr(str)

trims input string from left or right

explode / implode

convert string to Unicode code point, or convert Unicode code point to string

$ echo '"matrix"' | jq 'explode'
[
  109,
  97,
  116,
  114,
  105,
  120
]

$ echo "[109, 97, 116, 114, 105,  120]" | jq 'implode'
"matrix"

split(s) / join(s)

split input based by splitter s or join all elements with splitter s

$ echo '["matrix"]' | jq '.'
[
  "matrix"
]

$ echo '["matrix"]' | jq '.[] | split("")'
[
  "m",
  "a",
  "t",
  "r",
  "i",
  "x"
]

$ echo '["matrix"]' | jq '.[] | split("") | join("")'
"matrix"

ascii_upcase / ascii_downcase

convert input to UpperCase or Lowercase

$ echo '["matrix"]' | jq '.[] | ascii_upcase'
"MATRIX"

while(crondition; update) / until(crondition; next)

run update while contidion is true run next until until condition is true

$ echo 5 | jq '[., ., 1] | [while(.[1] > 0; [.[0], .[1] - 1, .[2] * .[1]])] | .[length -1][2]'
120

$ echo 5 | jq '[., 1] | until(.[0] < 1; [.[0] - 1, .[1] * .[0]]) | .[1]'
120

Examples

Show all keys

$ cat /tmp/data | jq '. | keys[]'
"Subnets"

$ cat /tmp/data | jq '.Subnets | keys[]'
0
1

Show Specific Element by Index

$ cat /tmp/data | jq '.Subnets[0]'
{
  "AvailabilityZone": "us-east-1a",
  "Tags": [
    {
      "Value": "DEV",
      "Key": "Env"
    },
    {
      "Value": "AccountBase",
      "Key": "aws:cloudformation:stack-name"
    },
    {
      "Value": "PrivateSubnet1a",
      "Key": "aws:cloudformation:logical-id"
    },
    {
      "Value": "Systems",
      "Key": "Owner"
    },
    {
      "Value": "PrivateSubnet1a",
      "Key": "Name"
    }
  ],
  "AvailableIpAddressCount": 214,
  "DefaultForAz": false,
  "Ipv6CidrBlockAssociationSet": [],
  "State": "available",
  "MapPublicIpOnLaunch": false,
  "SubnetId": "subnet-xxxxxx",
  "CidrBlock": "10.1.2.0/24",
  "AssignIpv6AddressOnCreation": false
}

Show Multi Attibutes

$ cat /tmp/data | jq '.Subnets[].SubnetId, .Subnets[].CidrBlock'
"subnet-xxxxxx"
"subnet-yyyyyy"
"10.1.2.0/24"
"10.1.0.0/24"

$ cat /tmp/data | jq '.Subnets[] | .SubnetId, .CidrBlock'
"subnet-xxxxxx"
"10.1.2.0/24"
"subnet-yyyyyy"
"10.1.0.0/24"

Filter by value

$ cat /tmp/data | jq '.Subnets[] | .SubnetId, .CidrBlock | select( . == "10.1.0.0/24" )'
"10.1.0.0/24"

$ cat /tmp/data | jq '.Subnets[] | .SubnetId, .CidrBlock | select( . | test(".*1.0.*") )'
"10.1.0.0/24"

$ cat /tmp/data | jq '.Subnets[] | {id: .SubnetId, network: .CidrBlock} | select(.network == "10.1.0.0/24")'
{
  "id": "subnet-yyyyyy",
  "network": "10.1.0.0/24"
}

Resharp json

$ cat /tmp/data | jq '.Subnets[] | { id: .SubnetId, ip_range: .CidrBlock }'
{
  "id": "subnet-xxxxxx",
  "ip_range": "10.1.2.0/24"
}
{
  "id": "subnet-yyyyyy",
  "ip_range": "10.1.0.0/24"
}

skip null iterator with ?

$ cat /tmp/ss-instances | jq ' .[][].Instances[] | {id: .InstanceId, tags: .Tags[]} | select(.tags.Key | test("^Name$";"i")) | select(.tags.Value | test(".*netapp.*"))'
jq: error (at <stdin>:34578): Cannot iterate over null (null)

$ cat /tmp/ss-instances | jq ' .[][].Instances[] | {id: .InstanceId, tags: .Tags[]?} | select(.tags.Key | test("^Name$";"i")) | select(.tags.Value | test(".*netapp.*"))'
{
  "id": "i-0908ac3819044a7b4",
  "tags": {
    "Value": "fwawsnetapp01-mediator",
    "Key": "Name"
  }
}

filter case insensitive with "i"

$ cat /tmp/ss-instances | jq ' .[][].Instances[] | {id: .InstanceId, tags: .Tags[]?} | select(.tags.Key | test("^Name$";"i")) | select(.tags.Value | test(".*netapp.*";"i"))'
{
  "id": "i-0b92c0aa4b6758489",
  "tags": {
    "Value": "System-NetAppCloudManager",
    "Key": "Name"
  }
}
{
  "id": "i-0908ac3819044a7b4",
  "tags": {
    "Value": "fwawsnetapp01-mediator",
    "Key": "Name"
  }
}

filter value based on another is existed

$ cat /tmp/data
{
    "Subnets": [
        {
            "AvailabilityZone": "us-east-1a",
            "SubnetId": "subnet-xxxxxx"
        },
        {
            "SubnetId": "subnet-yyyyyy"
        }
    ]
}

$ jq '.Subnets[] | {az: .AvailabilityZone, subnet: .SubnetId} | select(.az != null).subnet ' /tmp/data
"subnet-xxxxxx"

combine 2 values

$ jq -r '.Subnets[] | (.AvailabilityZone + ", " + .CidrBlock)' /tmp/data
us-east-1a, 10.1.2.0/24
us-east-1a, 10.1.0.0/24

resharp result as an array

$ jq -r '[.Subnets[] | {info: (.AvailabilityZone + ", " + .CidrBlock)}]' /tmp/data
[
  {
    "info": "us-east-1a, 10.1.2.0/24"
  },
  {
    "info": "us-east-1a, 10.1.0.0/24"
  }
]

split

$ jq -r '.Subnets[] | .AvailabilityZone | split("-")[0]' /tmp/data
us
us

get substring with capture

Collects the named captures in a JSON object, with the name of each capture as the key, and the matched string as the corresponding value.

$ jq -r '.Subnets[].AvailabilityZone | capture("(?<country>[^-]+)")' /tmp/data
{
  "country": "us"
}
{
  "country": "us"
}

{% include links.html %}