Styjun

I have a deep json. Sometimes, I need to look for the json path for a key containing certain word.

 "apiVersion": "v1",
 "kind": "Pod",
 "metadata": 
 "creationTimestamp": "2019-03-28T21:09:42Z",
 "labels": 
 "bu": "finance",
 "env": "prod"
 ,
 "name": "auth",
 "namespace": "default",
 "resourceVersion": "2786",
 "selfLink": "/api/v1/namespaces/default/pods/auth",
 "uid": "ce73565a-519d-11e9-bcb7-0242ac110009"
 ,
 "spec": 
 "containers": [
 
 "command": [
 "sleep",
 "4800"
 ],
 "image": "busybox",
 "imagePullPolicy": "Always",
 "name": "busybox",
 "resources": ,
 "terminationMessagePath": "/dev/termination-log",
 "terminationMessagePolicy": "File",
 "volumeMounts": [
 
 "mountPath": "/var/run/secrets/kubernetes.io/serviceaccount",
 "name": "default-token-dbpcm",
 "readOnly": true
 
 ]
 
 ],
 "dnsPolicy": "ClusterFirst",
 "nodeName": "node01",
 "priority": 0,
 "restartPolicy": "Always",
 "schedulerName": "default-scheduler",
 "securityContext": ,
 "serviceAccount": "default",
 "serviceAccountName": "default",
 "terminationGracePeriodSeconds": 30,
 "tolerations": [
 
 "effect": "NoExecute",
 "key": "node.kubernetes.io/not-ready",
 "operator": "Exists",
 "tolerationSeconds": 300
 ,
 
 "effect": "NoExecute",
 "key": "node.kubernetes.io/unreachable",
 "operator": "Exists",
 "tolerationSeconds": 300
 
 ],
 "volumes": [
 
 "name": "default-token-dbpcm",
 "secret": 
 "defaultMode": 420,
 "secretName": "default-token-dbpcm"
 
 
 ]
 ,
 "status": 
 "conditions": [
 
 "lastProbeTime": null,
 "lastTransitionTime": "2019-03-28T21:09:42Z",
 "status": "True",
 "type": "Initialized"
 ,
 
 "lastProbeTime": null,
 "lastTransitionTime": "2019-03-28T21:09:50Z",
 "status": "True",
 "type": "Ready"
 ,
 
 "lastProbeTime": null,
 "lastTransitionTime": null,
 "status": "True",
 "type": "ContainersReady"
 ,
 
 "lastProbeTime": null,
 "lastTransitionTime": "2019-03-28T21:09:42Z",
 "status": "True",
 "type": "PodScheduled"
 
 ],
 "containerStatuses": [
 
 "containerID": "docker://b5be8275555ad70939401d658bb4e504b52215b70618ad43c2d0d02c35e1ae27",
 "image": "busybox:latest",
 "imageID": "docker-pullable://busybox@sha256:061ca9704a714ee3e8b80523ec720c64f6209ad3f97c0ff7cb9ec7d19f15149f",
 "lastState": ,
 "name": "busybox",
 "ready": true,
 "restartCount": 0,
 "state": 
 "running": 
 "startedAt": "2019-03-28T21:09:49Z"
 
 
 
 ],
 "hostIP": "172.17.0.37",
 "phase": "Running",
 "podIP": "10.32.0.4",
 "qosClass": "BestEffort",
 "startTime": "2019-03-28T21:09:42Z"
 

Currently If i need the podIP, then I do that this way to find the object which has the search keyword and then I build the path

curl myson | jq "[paths]" | grep "IP" --context=10

Is there any nice shortcut to simplify this? What I really need is - all the paths which could have the matching key.

spec.podIP
spec.hostIP

select paths containing keyword in their last element, and use join(".") to generate your desired output.

paths
| select(.[-1] | type == "string" and contains("keyword"))
| join(".")

• 
  .[-1] returns the last element of an array,


• 
  type == "string" is required because an array index is a number and numbers and strings can't be checked for their containment.

You may want to specify -r option.

As @JeffMercado implicitly suggested you can set the query from command line without touching the script:

jq -r 'paths
| select(.[-1] | type == "string" and contains($q))
| join(".")' file.json --arg q 'keyword'

You can stream the input in, which provides paths and values. You could then inspect the paths and optionally output the values.

$ jq --stream --arg pattern 'IP' '
select(length == 2 and any(.[0][] | strings; test($pattern)))
 | "(.[0] | join(".")): (.[1])"
' input.json
"status.hostIP: 172.17.0.37"
"status.podIP: 10.32.0.4"