apply condition on json file and fetch the value on that key value exists in linux

I have the packages.json file which contains the docker image details, looks like:

  "dependencies": [
{
  "name": "powershell-core",
  "type": "zip",
  "path": "Dependencies",
  "filename": "PowerShell-Core-6.2.3-win-x64.msi"
},
{
"name": "redis",
"type": "docker-image",
"path": "redis:6.0.10-alpine3.12",
"filename": ""
},
{
  "name": "keycloak",
  "type": "docker-image",
  "path": "jboss/keycloak:12.0.1",
  "filename": ""
},
]

The JSON data is semi-structured and all is not the same. Here I am trying to fetch specific data like "path" with condition like if its a "type": "docker-image" under "dependencies" then fetch it.

I have tried something like:

$ jq '.dependencies[2].path' packages.json

output:

"redis:6.0.10-alpine3.12"

So how to fetch all the "path" having "type" as "docker-image" under "dependencies" from the packages.json file and keep it in a file.

>Solution :

Use select to filter an array:

jq -r '.dependencies[] | select(.type == "docker-image").path' packages.json

The -r removes the double quotes around the paths.

Use redirection to save the output to a file:

... > output