So i make a curl command to a url which returns an array of objects
response= $(curl --locaiton --request GET "http://.....")
I need to iterate over the returned json and extract a single value..
The json is as follows:
{
data:[
{"name": "ABC", "value": 1},
{"name": "EFC", "value": 4},
{"name": "CEC", "value": 3}
]
}
Is there anyway in BASh i can extract the second object value.. by perhaps iterating and doing an IF
Use jq
A simple example to extract the 2nd entry of the array would be:
RESPONSE='{"data":[{"name":"ABC","value": 1},{"name":"EFC","value":4},{"name":"CEC","value":3}]}';
EXTRACTED=$(echo -n "$RESPONSE" | jq '.data[1]');
echo $EXTRACTED
jq is the most commonly used command/tool to parse JSON data from a shell script. Here is an example with your data:
#!/usr/bin/env sh
# JSON response
response='
{
"data": [
{"name": "ABC", "value": 1},
{"name": "EFC", "value": 4},
{"name": "CEC", "value": 3}]
}'
# Name of entry
name='EFC'
# Get value of entry
value=$( jq --null-input --raw-output --arg aName "$name" \
"$response"' | .data[] | select(.name == $aName) | .value')
# Print it out
printf 'value for %s is: %s\n' "$name" "$value"
Alternatively jq can be used to transform the whole JSON name value objects array, into a Bash associative array declaration:
#!/usr/bin/env bash
# JSON response
response='
{
"data": [
{"name": "ABC", "value": 1},
{"name": "EFC", "value": 4},
{"name": "CEC", "value": 3}]
}'
# Name of entry
name='EFC'
# Covert all JSON array name value entries into a Bash associative array
# shellcheck disable=SC2155 # safe generated declaration
declare -A entries="($( jq --null-input --raw-output \
"$response"' | .data[] | ( "[" + ( .name | @sh ) + "]=" + (.value | @sh) )'))"
# Print it out
printf 'value for %s is: %s\n' "$name" "${entries[$name]}"
data:[is invalid json.