I have a variable (via set_fact) containing a json string:
{
"PolicyVersion": {
"CreateDate": "2017-08-07T02:48:05Z",
"Document": {
"Statement": [
{
"Action": "sts:AssumeRole",
"Effect": "Allow",
"Resource": [
"arn:aws:iam::123456789123:role/Root_Update_svcacct",
"arn:aws:iam::123456789123:role/Root_Delete_svcacct",
"arn:aws:iam::123456789123:role/Root_Create_svcacct",
"arn:aws:iam::123456789123:role/Root_Full_svcacct",
"arn:aws:iam::987654321987:role/Member1_Create_svcacct",
"arn:aws:iam::987654321987:role/Member1_Update_svcacct",
"arn:aws:iam::987654321987:role/Member1_Delete_svcacct",
"arn:aws:iam::987654321987:role/Member1_Full_svcacct"
]
}
],
"Version": "2012-10-17"
},
"IsDefaultVersion": true,
"VersionId": "v2"
}
}
What is the best way to insert more elements in the "Resource" array?
"arn:aws:iam::001122334455:role/Member1_Create_svcacct",
"arn:aws:iam::001122334455:role/Member1_Update_svcacct",
"arn:aws:iam::001122334455:role/Member1_Delete_svcacct",
"arn:aws:iam::001122334455:role/Member1_Full_svcacct"
I am exploring dumping the variable to a file and inserting the block I want with external shell tools, which does not seem to be elegant.
I don't know about the best way, but one option is to write a simple library module to handle the mechanics of the update for you. You could use the jsonpointer
module as a way of locating the data you wish to modify, and then return the modified object to ansible. A starting point might look like:
#!/usr/bin/python
from ansible.module_utils.basic import AnsibleModule
import json
try:
import jsonpointer
except ImportError:
jsonpointer = None
def main():
module = AnsibleModule(
argument_spec=dict(
data=dict(required=True, type='dict'),
pointer=dict(required=True),
action=dict(required=True,
choices=['append', 'extend', 'update']),
update=dict(type='dict'),
extend=dict(type='list'),
append=dict(),
),
supports_check_mode=True,
)
if jsonpointer is None:
module.fail_json(msg='jsonpointer module is not available')
action = module.params['action']
data = module.params['data']
pointer = module.params['pointer']
if isinstance(data, str):
data = json.loads(str)
try:
res = jsonpointer.resolve_pointer(data, pointer)
except jsonpointer.JsonPointerException as err:
module.fail_json(msg=str(err))
if action == 'append':
res.append(module.params['append'])
if action == 'extend':
res.extend(module.params['extend'])
elif action == 'update':
res.update(module.params['update'])
module.exit_json(changed=True,
result=data)
if __name__ == '__main__':
main()
If you drop this into, e.g., library/json_modify.py
, you can use it in a playbook like this:
- hosts: localhost
gather_facts: false
vars:
myvar: {
"PolicyVersion": {
"CreateDate": "2017-08-07T02:48:05Z",
"Document": {
"Statement": [
{
"Action": "sts:AssumeRole",
"Effect": "Allow",
"Resource": [
"arn:aws:iam::123456789123:role/Root_Update_svcacct",
"arn:aws:iam::123456789123:role/Root_Delete_svcacct",
"arn:aws:iam::123456789123:role/Root_Create_svcacct",
"arn:aws:iam::123456789123:role/Root_Full_svcacct",
"arn:aws:iam::987654321987:role/Member1_Create_svcacct",
"arn:aws:iam::987654321987:role/Member1_Update_svcacct",
"arn:aws:iam::987654321987:role/Member1_Delete_svcacct",
"arn:aws:iam::987654321987:role/Member1_Full_svcacct"
]
}
],
"Version": "2012-10-17"
},
"IsDefaultVersion": true,
"VersionId": "v2"
}
}
tasks:
- json_modify:
data: "{{ myvar }}"
pointer: "/PolicyVersion/Document/Statement/0/Resource"
action: extend
extend:
- "arn:aws:iam::001122334455:role/Member1_Create_svcacct"
- "arn:aws:iam::001122334455:role/Member1_Update_svcacct"
- "arn:aws:iam::001122334455:role/Member1_Delete_svcacct"
- "arn:aws:iam::001122334455:role/Member1_Full_svcacct"
register: result
- debug:
var: result.result
The result of running this playbook and the proposed module is:
TASK [debug] *******************************************************************
ok: [localhost] => {
"result.result": {
"PolicyVersion": {
"CreateDate": "2017-08-07T02:48:05Z",
"Document": {
"Statement": [
{
"Action": "sts:AssumeRole",
"Effect": "Allow",
"Resource": [
"arn:aws:iam::123456789123:role/Root_Update_svcacct",
"arn:aws:iam::123456789123:role/Root_Delete_svcacct",
"arn:aws:iam::123456789123:role/Root_Create_svcacct",
"arn:aws:iam::123456789123:role/Root_Full_svcacct",
"arn:aws:iam::987654321987:role/Member1_Create_svcacct",
"arn:aws:iam::987654321987:role/Member1_Update_svcacct",
"arn:aws:iam::987654321987:role/Member1_Delete_svcacct",
"arn:aws:iam::987654321987:role/Member1_Full_svcacct",
"arn:aws:iam::001122334455:role/Member1_Create_svcacct",
"arn:aws:iam::001122334455:role/Member1_Update_svcacct",
"arn:aws:iam::001122334455:role/Member1_Delete_svcacct",
"arn:aws:iam::001122334455:role/Member1_Full_svcacct"
]
}
],
"Version": "2012-10-17"
},
"IsDefaultVersion": true,
"VersionId": "v2"
}
}
}