Bash script - unable to replace string with double quotes and curly braces - json

Question

I'm struggling for some time and I would need some help with the following operation.
I have a JSON file and I would like to replace a string with something a bit more complex.
This is a snippet of my json file:
{ "AWS679f53fac002430cb0da5b7982bd22872D164C4C": {
"Type": "AWS::Lambda::Function",
"Properties": {
"Code": {
"S3Bucket": "hnb659fds-assets-xxccddff",
"S3Key": "68b4ffa1c39cb3733535725f85311791c09eab53b7ab8efa5152e68f8abdb005.zip"
},
"Role": {
"Fn::GetAtt": [
"AWS679f53fac002430cb0da5b7982bd2287ServiceRoleC1EA0FF2",
"Arn"
]
},
"Handler": "index.handler",
"Runtime": "nodejs12.x",
"Timeout": 120
},
"DependsOn": [
"AWS679f53fac002430cb0da5b7982bd2287ServiceRoleC1EA0FF2"
],
"Metadata": {
"aws:cdk:path": "CODE/AWS679f53fac002430cb0da5b7982bd2287/Resource",
"aws:asset:path": "asset.68b4ffa1c39cb3733535725f85311791c09eab53b7ab8efa5152e68f8abdb005",
"aws:asset:is-bundled": false,
"aws:asset:property": "Code"
}
}
}
What I need is to replace this part
"S3Bucket": "hnb659fds-assets-xxccddff",
and have the following result
"S3Bucket": {"Fn::Sub": "AAA-${AWS::Region}" },
I don't know the AWS679f53fac002430cb0da5b7982bd22872D164C4C. It is generated randomly and the string to replace is present several times in my json file.
The initial values to be replaced is stored in a variable along with the new value to be used in the replaced version as following:
cdk_bucket_name=hnb659fds-assets-xxccddff
OUTPUT_BUCKET=AAA
I need these variables because this is part of a bigger script
So I tried some sed but does not work
new_bucket_name="{"Fn::Sub\": \"$OUTPUT_BUCKET-${AWS::Region}\" }"
sed -i "s#$cdk_bucket_name#$new_bucket_name#g" my.template.json
One issue that I have is that ${AWS::Region} gets interpreted so is empty.
And second, I cannot manage the quotes in order to have my desired result.

Answer 1

Using sed
$ output_bucket=AAA
$ new_bucket_name="{\"Fn::Sub\": \"$output_bucket-\${AWS::Region}\" }"
$ cdk_bucket_name=hnb659fds-assets-xxccddff
$ sed s"/\"$cdk_bucket_name\"/$new_bucket_name/" input_file
{ "AWS679f53fac002430cb0da5b7982bd22872D164C4C": {
"Type": "AWS::Lambda::Function",
"Properties": {
"Code": {
"S3Bucket": {"Fn::Sub": "AAA-${AWS::Region}" },
"S3Key": "68b4ffa1c39cb3733535725f85311791c09eab53b7ab8efa5152e68f8abdb005.zip"
},
"Role": {
"Fn::GetAtt": [
"AWS679f53fac002430cb0da5b7982bd2287ServiceRoleC1EA0FF2",
"Arn"
]
},
"Handler": "index.handler",
"Runtime": "nodejs12.x",
"Timeout": 120
},
"DependsOn": [
"AWS679f53fac002430cb0da5b7982bd2287ServiceRoleC1EA0FF2"
],
"Metadata": {
"aws:cdk:path": "CODE/AWS679f53fac002430cb0da5b7982bd2287/Resource",
"aws:asset:path": "asset.68b4ffa1c39cb3733535725f85311791c09eab53b7ab8efa5152e68f8abdb005",
"aws:asset:is-bundled": false,
"aws:asset:property": "Code"
}
}
}

Answer 2

Using a proper JSON parser shell tool like jq:
jq '
(
.[].Properties.Code.S3Bucket |
select(. == "hnb659fds-assets-xxccddff")
) = $newS3Bucket
' input_file.json \
--argjson newS3Bucket '{"Fn::Sub":"AAA-${AWS::Region}"}'