Combining JSON by common key-value pairs

Question

I\'m currently working through an issue, and can\'t seem to figure this one out. Here\'s some data so you know what I\'m talking about below:

foo.json

Answer 1

With foobar.jq as follows:

def dict(f):
  reduce .[] as $o ({}; .[$o | f | tostring] = $o ) ;

($bar | dict(.deviceId)) as $dict
| .Schedule |= map(. + ($dict[.deviceId|tostring] ))

the invocation:

jq -f foobar.jq --argfile bar bar.json foo.json

yields the output shown below.

Notice that the referents in the dictionary contain the full object (including the key/value pair for "deviceId"), but it's not necessary to del(.deviceId) because of the way + is defined in jq.

Output

{
  "Schedule": [
    {
      "deviceId": 123,
      "reservationId": 123456,
      "username": "jdoe",
      "a": {
        "b": "10.0.0.1",
        "c": "hostname1"
      }
    },
    {
      "deviceId": 456,
      "reservationId": 589114,
      "username": "jsmith",
      "a": {
        "b": "10.0.0.2",
        "c": "hostname2"
      }
    }
  ],
  "serverTime": 1522863125.019958
}