How to find and replace json with shell variables using jq? - json

Question

I have read properties with jq from a json object and have stored them to variables.
I want to now read these variables and essentially find and replace a word inside the string with a global shell variable.
I've set my json ID's from my JSON file
# Set Json ID's
TARGET_ID=$(jq '.DefaultCacheBehavior.TargetOriginId' distconfig.json)
DOMAIN_NAME=$(jq '.Origins.Items[0].DomainName' distconfig.json)
ORIGIN_ID=$(jq '.Origins.Items[0].Id' distconfig.json)
echo "$TARGET_ID"
echo "$DOMAIN_NAME"
echo "$ORIGIN_ID"
This returns
"S3-Website-stag4.example.io.s3-website.us-east-2.amazonaws.com"
"stag4.example.io.s3-website.us-east-2.amazonaws.com"
"S3-Website-stag4.example.io.s3-website.us-east-2.amazonaws.com"
I have my location id variable and would like to write it to find and replace all stag4 references in those 3 ID's.
Then I would like to write those 3 ID's to the initial json object, or create a temp version of it.
Example, if:
$DOMAIN_NAME is"stag4.example.io.s3-website.us-east-2.amazonaws.com"
I would like to essentially have it set to:
$LOCATION_NAME="stag6"
DOMAIN_LOCATION="example.io"
"$DOMAIN_NAME=S3-Website-\$LOCATION_NAME\.example.io.s3-website.us-east-2.amazonaws.com"
"$TARGET_ID=\$LOCATION_NAME\.example.io.s3-website.us-east-2.amazonaws.com"
"$ORIGIN_ID=S3-Website-\$LOCATION_NAME\.example.io.s3-website.us-east-2.amazonaws.com"
Then write those 3 to the temp or new json file so I can run my cloudformation command:
aws cloudfront create-distribution --distribution-config file://disttemp.json
I have now built out the proper variables from the initial json file like so:
$LOCATION_NAME="stag6"
DOMAIN_LOCATION="example.io"
echo "Build New IDs"
TARGET_ID_BUILT="S3-Website-$LOCATION_NAME.$DOMAIN_LOCATION.s3-website.us-east-2.amazonaws.com"
DOMAIN_NAME_BUILT="$LOCATION_NAME.$DOMAIN_LOCATION.s3-website.us-east-2.amazonaws.com"
ORIGIN_ID_BUILT="S3-Website-$LOCATION_NAME.$DOMAIN_LOCATION.s3-website.us-east-2.amazonaws.com"
echo "$TARGET_ID_BUILT"
echo "$DOMAIN_NAME_BUILT"
echo "$ORIGIN_ID_BUILT"
How do I write these variables to the json file with jq?
EDIT: Sample of distconfig.json requested – domain/creds swapped to example
{
"CallerReference": "my-test-distribution-2",
"Comment": "",
"CacheBehaviors": {
"Quantity": 0
},
"IsIPV6Enabled": true,
"Logging": {
"Bucket": "",
"Prefix": "",
"Enabled": false,
"IncludeCookies": false
},
"WebACLId": "",
"Origins": {
"Items": [
{
"OriginPath": "",
"CustomOriginConfig": {
"OriginSslProtocols": {
"Items": [
"TLSv1",
"TLSv1.1",
"TLSv1.2"
],
"Quantity": 3
},
"OriginProtocolPolicy": "http-only",
"OriginReadTimeout": 30,
"HTTPPort": 80,
"HTTPSPort": 443,
"OriginKeepaliveTimeout": 5
},
"CustomHeaders": {
"Quantity": 0
},
"Id": "S3-Website-stag4.example.io.s3-website.us-east-2.amazonaws.com",
"DomainName": "stag4.example.io.s3-website.us-east-2.amazonaws.com"
}
],
"Quantity": 1
},
}
"DefaultRootObject": "",
"PriceClass": "PriceClass_All",
"Enabled": true,
"DefaultCacheBehavior": {
"TrustedSigners": {
"Enabled": false,
"Quantity": 0
},
"LambdaFunctionAssociations": {
"Quantity": 0
},
"TargetOriginId": "S3-Website-stag4.example.io.s3-website.us-east-2.amazonaws.com",
"ViewerProtocolPolicy": "redirect-to-https",
"ForwardedValues": {
"Headers": {
"Quantity": 0
},
"Cookies": {
"Forward": "none"
},
"QueryStringCacheKeys": {
"Quantity": 0
},
"QueryString": false
},
"MaxTTL": 31536000,
"SmoothStreaming": false,
"DefaultTTL": 86400,
"AllowedMethods": {
"Items": [
"HEAD",
"GET"
],
"CachedMethods": {
"Items": [
"HEAD",
"GET"
],
"Quantity": 2
},
"Quantity": 2
},
"MinTTL": 0,
"Compress": true
},
"ViewerCertificate": {
"SSLSupportMethod": "sni-only",
"ACMCertificateArn": "xxxx",
"MinimumProtocolVersion": "TLSv1.1_2016",
"Certificate": "xxxx",
"CertificateSource": "acm"
},
"CustomErrorResponses": {
"Quantity": 0
},
"HttpVersion": "http2",
"Restrictions": {
"GeoRestriction": {
"RestrictionType": "none",
"Quantity": 0
}
},
"Aliases": {
"Quantity": 0
}
}

Answer 1

You should use sed to do the substitution and then inject the value back into the JSON.
echo $TARGET_ID | sed 's/stag4/stag5/g'
Outputs
S3-Website-stag5.example.io.s3-website.us-east-2.amazonaws.com
Next we'll put the value back into the original JSON, this will technically output a new JSON and does not edit the file, however, you can easily solve for this on the output by temporarily saving to a tmp file.
We will use the --arg flag to reference our bash variable and set the new value for our field
cat distconfig.json | jq --arg  TARGET_ID $TARGET_ID '.DefaultCacheBehavior.TargetOriginId = $TARGET_ID' > tmp.json && mv tmp.json distconfig.json