Filter a JSON document in Ansible - json

Question

I have a JSON reply from a GitHub repository with a list of possible downloads for a certain release (the assets array in the document).
I want to get the browser download URL when the name of an asset ends with x64.AppImage.
In Ansible, the filters are built apon jmespath and using its terminal tool, I can query the url with the following expression:
assets[?ends_with(name, 'x64.AppImage')].browser_download_url
With the following playbook, the JSON document is queried and stored in the json_reply variable.
---
- hosts: local
tasks:
- name: Get list of Rambox releases
uri:
url: "https://api.github.com/repos/saenzramiro/rambox/releases/latest"
body_format: json
register: json_reply
- name: Filter reply
debug: URL -> "{{ item }}"
with_items:
- "{{ json_reply.json | json_query(json_filter) }}"
vars:
- json_filter: assets[?ends_with(name, 'x64.AppImage')].browser_download_url
However, executing this gives the following error:
fatal: [localhost]: FAILED! => {
"msg": "JMESPathError in json_query filter plugin:\nIn function ends_with(), invalid type for value: latest-mac.json, expected one of: ['string'], received: \"unknown\""
}
Where latest-mac.json is the first object in the assets array.
How can I make Ansible to iterate over all the assets array and apply my filter?
PS:
If instead of querying if the name ends with a word I specify it directly, the filter works:
assets[?name == 'Rambox-0.5.13-x64.AppImage')].browser_download_url
JSON example:
{
"url": "https://api.github.com/repos/saenzramiro/rambox/releases/8001922",
"prerelease": false,
"created_at": "2017-10-04T21:14:15Z",
"published_at": "2017-10-05T01:10:55Z",
"assets": [
{
"url": "https://api.github.com/repos/saenzramiro/rambox/releases/assets/4985942",
"id": 4985942,
"name": "latest-mac.json",
"uploader": {
"login": "saenzramiro",
"id": 2694669
},
"browser_download_url": "https://github.com/saenzramiro/rambox/releases/download/0.5.13/latest-mac.json"
},
{
"url": "https://api.github.com/repos/saenzramiro/rambox/releases/assets/4985640",
"id": 4985640,
"name": "Rambox-0.5.13-x64.AppImage",
"uploader": {
"login": "saenzramiro",
"id": 2694669
},
"browser_download_url": "https://github.com/saenzramiro/rambox/releases/download/0.5.13/Rambox-0.5.13-x64.AppImage"
}
],
"tarball_url": "https://api.github.com/repos/saenzramiro/rambox/tarball/0.5.13"
}

Answer 1

The problem of type errors in JMESPath filters is discussed in issue 27299.
You can use this patched json_query.py filter plugin.
Or apply double conversion to your object as a workaround: | to_json | from_json |.
This will convert object to JSON (thus plain strings) and back, so json_query will treat strings as supported type.

Answer 2

Loop through each asset
Print the browser URL of the item if it ends with x64.AppImage
Solution not using JMESPath:
- name: Filter reply
debug: var=item.browser_download_url
with_items: "{{ json_reply.json.assets }}"
when: item.browser_download_url | regex_search('x64.AppImage$')

Answer 3

As #helloV said, you can accomplish this using Ansible loops, although there's no reason to involve a regular expression match. You can use the same test you're already using:
- name: Filter reply
debug:
var: item.browser_download_url
with_items: "{{ json_reply.json.assets }}"
when: item.name.endswith('x64.AppImage')
The root problem would appear to be an Ansible bug. The error comes from the following check in the jmespath library:
if actual_typename not in allowed_types:
raise exceptions.JMESPathTypeError(
function_name, current,
self._convert_to_jmespath_type(actual_typename), types)
At the point this code is called, the data type of values in your json response is AnsibleUnsafeText, where as allowed_types is [str, unicode]. I think the transformation of values from native types to the AnsibleUnsafeText type probably is some sort of standard Ansible module behavior being imposed by the uri module. We can work around it by using curl instead, like this:
- name: Get list of Rambox releases
command: >
curl -s "https://api.github.com/repos/saenzramiro/rambox/releases/latest"
register: json_reply
And then:
- name: Filter reply
debug:
var: item.browser_download_url
with_items: >
{{ json_reply.stdout|from_json|json_query('assets[?ends_with(name, `x64.AppImage`)]') }}