Build a JSON string with Bash variables

Question

I need to read these bash variables into my JSON string and I am not familiar with bash. any help is appreciated.

#!/bin/sh

BUCKET_NAME=testbucket
OBJECT_N         


        

Answer 1

These solutions come a little late but I think they are inherently simpler that previous suggestions (avoiding the complications of quoting and escaping).

    BUCKET_NAME=testbucket
    OBJECT_NAME=testworkflow-2.0.1.jar
    TARGET_LOCATION=/opt/test/testworkflow-2.0.1.jar
    
    # Initial unsuccessful solution
    JSON_STRING='{"bucketname":"$BUCKET_NAME","objectname":"$OBJECT_NAME","targetlocation":"$TARGET_LOCATION"}'
    echo $JSON_STRING 
    
    # If your substitution variables have NO whitespace this is sufficient
    JSON_STRING=$(tr -d [:space:] <