[FIXED] How to add a new key-value pair to each object in a JSON array

Issue

How can I add a new key-value pair to each of the objects in a JSON array as shown below? I tried using the below code, but the result is separated instead of being in the same, original array.

import json

json_var = '''{
"information" : {
  "info_id"          : "8878",
  "info_name"        : "Stackoverflow"
},

"env" : {
  "env_name"           : "UAT",
  "env_type"           : "Staging"
},

"services" : [
  {
    "service_name"         : "stack1",
    "service_version"     : "1"
  },
  {
    "service_name"         : "stack2",
    "service_version"     : "2"
  },  
  {
    "service_name"         : "stack3",
    "service_version"     : "3"
  }
 ]
}'''

y = {"pin":110096}
entry = json.loads(json_var)

for i in entry['services']:
      i.update(y)
      print(json.dumps(i))

Actual output:

{"service_name": "stack1", "service_version": "1", "pin": 110096}
{"service_name": "stack2", "service_version": "2", "pin": 110096}
{"service_name": "stack3", "service_version": "3", "pin": 110096}

Expected output:

[
{"service_name": "stack1", 
  "service_version": "1", 
  "pin": 110096
},
{"service_name": "stack2",
 "service_version": "2",
 "pin": 110096
},
{"service_name": "stack3",
 "service_version": "3",
 "pin": 110096
}
]

Please advise on how to modify the above code or provide new code to achieve the expected output.

Solution

The only issue is with the placement of your print() statement. It should be outside of the for loop, and you should be printing entry['services'] rather than i. This allows you to print all of updated entries at once, rather than one at a time.

y = {"pin":110096}
entry = json.loads(json_var)

for i in entry['services']:
    i.update(y)

print(json.dumps(entry['services']))

This outputs:

[{"service_name": "stack1", "service_version": "1", "pin": 110096},
{"service_name": "stack2", "service_version": "2", "pin": 110096},
{"service_name": "stack3", "service_version": "3", "pin": 110096}]

Answered By - BrokenBenchmark