Getting the values of keys of Ansible JSON output - ansible

Question

I have the following JSON data
{
"docker_compose_init_result": {
"changed": true,
"failed": false,
"services": {
"grafana": {
"docker-compose_grafana_1": {
"cmd": [],
"image": "grafana/grafana:8.5.14",
"labels": {
"com.docker.compose.config-hash": "4d0b5dd6e697a8fe5bf5074192770285e54da43ad32cc34ba9c56505cb709431",
"com.docker.compose.container-number": "1",
"com.docker.compose.oneoff": "False",
"com.docker.compose.project": "docker-compose",
"com.docker.compose.project.config_files": "/appl/docker-compose/docker-compose-init.yml",
"com.docker.compose.project.working_dir": "/appl/docker-compose",
"com.docker.compose.service": "grafana",
"com.docker.compose.version": "1.29.2"
},
"networks": {
"docker-compose_homeserver-net": {
"IPAddress": "172.20.0.2",
"IPPrefixLen": 16,
"aliases": [
"3d19f54271b2",
"grafana"
],
"globalIPv6": "",
"globalIPv6PrefixLen": 0,
"links": null,
"macAddress": "02:42:ac:14:00:02"
}
},
"state": {
"running": true,
"status": "running"
}
}
},
"node-red": {
"docker-compose_node-red_1": {
"cmd": [],
"image": "nodered/node-red:2.2.2",
"labels": {
"authors": "Dave Conway-Jones, Nick O'Leary, James Thomas, Raymond Mouthaan",
"com.docker.compose.config-hash": "5610863d4b28b11645acb5651e7bab174125743dc86a265969788cc8ac782efe",
"com.docker.compose.container-number": "1",
"com.docker.compose.oneoff": "False",
"com.docker.compose.project": "docker-compose",
"com.docker.compose.project.config_files": "/appl/docker-compose/docker-compose-init.yml",
"com.docker.compose.project.working_dir": "/appl/docker-compose",
"com.docker.compose.service": "node-red",
"com.docker.compose.version": "1.29.2",
"org.label-schema.arch": "",
"org.label-schema.build-date": "2022-02-18T21:01:04Z",
"org.label-schema.description": "Low-code programming for event-driven applications.",
"org.label-schema.docker.dockerfile": ".docker/Dockerfile.alpine",
"org.label-schema.license": "Apache-2.0",
"org.label-schema.name": "Node-RED",
"org.label-schema.url": "https://nodered.org",
"org.label-schema.vcs-ref": "",
"org.label-schema.vcs-type": "Git",
"org.label-schema.vcs-url": "https://github.com/node-red/node-red-docker",
"org.label-schema.version": "2.2.2"
},
"networks": {
"docker-compose_homeserver-net": {
"IPAddress": "172.20.0.4",
"IPPrefixLen": 16,
"aliases": [
"fc56e973c98d",
"node-red"
],
"globalIPv6": "",
"globalIPv6PrefixLen": 0,
"links": null,
"macAddress": "02:42:ac:14:00:04"
}
},
"state": {
"running": true,
"status": "running"
}
}
},
"organizr": {
"docker-compose_organizr_1": {
"cmd": [],
"image": "organizr/organizr:linux-amd64",
"labels": {
"base.maintainer": "christronyxyocum,Roxedus",
"base.s6.arch": "amd64",
"base.s6.rel": "2.2.0.3",
"com.docker.compose.config-hash": "430b338b0c0892a25522e1b641a9e3a08eedd255309b1cd275b22a3362dcac58",
"com.docker.compose.container-number": "1",
"com.docker.compose.oneoff": "False",
"com.docker.compose.project": "docker-compose",
"com.docker.compose.project.config_files": "/appl/docker-compose/docker-compose-init.yml",
"com.docker.compose.project.working_dir": "/appl/docker-compose",
"com.docker.compose.service": "organizr",
"com.docker.compose.version": "1.29.2",
"maintainer": "christronyxyocum,Roxedus",
"org.label-schema.description": "Baseimage for Organizr",
"org.label-schema.name": "organizr/base",
"org.label-schema.schema-version": "1.0",
"org.label-schema.url": "https://organizr.app/",
"org.label-schema.vcs-url": "https://github.com/organizr/docker-base",
"org.opencontainers.image.created": "2022-05-08_15",
"org.opencontainers.image.source": "https://github.com/Organizr/docker-organizr/tree/master",
"org.opencontainers.image.title": "organizr/base",
"org.opencontainers.image.url": "https://github.com/Organizr/docker-organizr/blob/master/README.md"
},
"networks": {
"docker-compose_homeserver-net": {
"IPAddress": "172.20.0.3",
"IPPrefixLen": 16,
"aliases": [
"organizr",
"f3f61d8938fe"
],
"globalIPv6": "",
"globalIPv6PrefixLen": 0,
"links": null,
"macAddress": "02:42:ac:14:00:03"
}
},
"state": {
"running": true,
"status": "running"
}
}
},
"prometheus": {
"docker-compose_prometheus_1": {
"cmd": [
"--config.file=/etc/prometheus/prometheus.yml",
"--storage.tsdb.path=/prometheus",
"--web.console.libraries=/etc/prometheus/console_libraries",
"--web.console.templates=/etc/prometheus/consoles",
"--web.enable-lifecycle"
],
"image": "prom/prometheus:v2.35.0",
"labels": {
"com.docker.compose.config-hash": "7d2ce7deba1a152ebcf4fe5494384018c514f6703b5e906aef6f2e8820733cb2",
"com.docker.compose.container-number": "1",
"com.docker.compose.oneoff": "False",
"com.docker.compose.project": "docker-compose",
"com.docker.compose.project.config_files": "/appl/docker-compose/docker-compose-init.yml",
"com.docker.compose.project.working_dir": "/appl/docker-compose",
"com.docker.compose.service": "prometheus",
"com.docker.compose.version": "1.29.2",
"maintainer": "The Prometheus Authors <prometheus-developers#googlegroups.com>"
},
"networks": {
"docker-compose_homeserver-net": {
"IPAddress": "172.20.0.5",
"IPPrefixLen": 16,
"aliases": [
"04f346e6694f",
"prometheus"
],
"globalIPv6": "",
"globalIPv6PrefixLen": 0,
"links": null,
"macAddress": "02:42:ac:14:00:05"
}
},
"state": {
"running": true,
"status": "running"
}
}
}
}
}
}
And I need an output similar to
- docker-compose_grafana_1
- docker-compose_node-red_1
- docker-compose_organizr_1
- docker-compose_prometheus_1
I can do that with jq easy-peasy:
jq --raw-output '.docker_compose_init_result.services\[\] | keys | .\[\]' jsondata.json
But I am not able to do it with Ansible and especially json_query (and thus JMESPath).
I was able to get one key with
jp -f jsondata.json "keys(docker_compose_init_result.services.grafana)"
[
"docker-compose_grafana_1"
]
But have no idea how to get all four. Also sometimes expressions that worked with jp did not work in Ansible with json_query, which additionally made me mad.
If anyone can give me a solution for this (wether its with json_query or not) in the best case explains how it works, I would be very glad.

Answer 1

Solution using only builtin filters:
docker_compose_list: "{{ docker_compose_init_result.services | dict2items
| map(attribute='value') | map('dict2items')
| flatten | map(attribute='key') }}"
which gives once expanded:
{
"docker_compose_list": [
"docker-compose_grafana_1",
"docker-compose_node-red_1",
"docker-compose_organizr_1",
"docker-compose_prometheus_1"
]
}

Answer 2

In a pure JMESPath way, you query should be:
docker_compose_init_result.services.*.keys(#)[]
Where:
.* is the notation for an object project, that will make you get the values under docker_compose_init_result.services, whatever the key might be.
.keys(#) is the keys() function, in order to get the keys, mapped to the current node — #, which effectively means that keys() is going to be applied to every object which are children of docker_compose_init_result.services.*, (e.g.: on docker_compose_init_result.services.grafana."docker-compose_grafana_1", docker_compose_init_result.services."node-red"."docker-compose_node-red_1", and so on)
[] is the flatten operator, in order to reduce your array of arrays to a single level array

Answer 3

The query below
docker_compose_list: "{{ docker_compose_init_result|
json_query(_query) }}"
_query: 'services.*.keys(#)'
gives
docker_compose_list:
- - docker-compose_grafana_1
- - docker-compose_node-red_1
- - docker-compose_organizr_1
- - docker-compose_prometheus_1
Select first items
docker_compose_list: "{{ docker_compose_init_result|
json_query(_query)|
map('first')|list }}"
or flatten the list
docker_compose_list: "{{ docker_compose_init_result|
json_query(_query)|
flatten }}"
both give
docker_compose_list:
- docker-compose_grafana_1
- docker-compose_node-red_1
- docker-compose_organizr_1
- docker-compose_prometheus_1
Note: Be careful how you select or flatten the list. There might be a reason for the second-level keys. For example, if there are more keys in services.grafana the result might be
docker_compose_list:
- - docker-compose_grafana_1
- docker-compose_grafana_2
- docker-compose_grafana_3
- - docker-compose_node-red_1
- - docker-compose_organizr_1
- - docker-compose_prometheus_1
In this case, taking the first item or flattening the list doesn't necessarily give the result you want.