Update one JSON file values with values from another JSON using JQ

Question

So I have two JSON files:

bosh.json:

{
  \"key_pair_name\": \"my-aws-keypair\",
  \"ssh_private_key\": \"my-key-name\",
  \"trusted_certific         


        

Answer 1

The requirements are not completely clear, but here's the solution to one interpretation. This solution can easily be modified to match the other obvious interpretation.

Assuming the file bosh.jq contains the following jq program:

reduce keys[] as $k (.; if $bosh|has($k) then .[$k] = $bosh[$k] else . end)

then the command:

jq --argfile bosh bosh.json -f bosh.jq model.json

will in effect emit the edited version of model.json.

Using with_entries

If you prefer a reduce-free approach, consider:

with_entries(.key as $k | if $bosh|has($k) then .value = $bosh[$k] else . end )

Note that if $bosh|has($k) ... is NOT the same as if $bosh[$k] ....

Answer 2

jq solution:

jq --argfile bosh bosh.json 'with_entries( 
         if $bosh[.key] then .value = $bosh[.key] else . end)' model.json

The output:

{
  "trusted_certificates": "my-trusted-certs",
  "vm_password_type": "generate"
}

---

• if $bosh[.key] then .value = $bosh[.key] else . end - update model's value only for matched keys