Hi,
I’m trying to extend the ZFS module to add support for user properties.
My plan was to add a new module argument, called (guess what)
`user_properties` which accepts a list of dictionaries:
[{key: 'my.module.name:key-name', value: 'whatever'}, ...]
However, I get this error message:
msg: this module requires key=value arguments
Even though I can pass an empty list or a list with string items, like
['a', 'b', 'c'].
Is there a way to do this?
Thank you.
(This is really a question for ansible-devel list)
In the argument_spec of the module that defines the argument, just do
type=‘dict’
It will accept complex arguments as well as quoted key=value pairs.
module_name:
foo:
x: 1
y: “bar”
baz: “glorp”
Is how complex args are passed
Or
module_name: ‘foo=“x=1 y=bar” baz=“glorp”’
This is exactly how the ec2 module in 1.4/1.5 processes and passes instance tags, if you want to take a look.
It also knows how to parse inline JSON, so it is very much a “do what you mean” kind of input.
Michael DeHaan <michael@ansibleworks.com> writes:
(This is really a question for ansible-devel list)
Thank you for pointing it out, I wasn’t sure about that.
In the argument_spec of the module that defines the argument, just do
type='dict'
It will accept complex arguments as well as quoted key=value pairs.
module_name:
foo:
x: 1
y: "bar"
baz: "glorp"Is how complex args are passed
Or
module_name: 'foo="x=1 y=bar" baz="glorp"'
This is exactly how the ec2 module in 1.4/1.5 processes and passes instance
tags, if you want to take a look.It also knows how to parse inline JSON, so it is very much a "do what you
mean" kind of input.
Super. Thanks a lot.
Michael DeHaan <michael@ansibleworks.com> writes:
In the argument_spec of the module that defines the argument, just do
type='dict'
It will accept complex arguments as well as quoted key=value pairs.
module_name:
foo:
x: 1
y: "bar"
baz: "glorp"Is how complex args are passed
Or
module_name: 'foo="x=1 y=bar" baz="glorp"'
This is exactly how the ec2 module in 1.4/1.5 processes and passes instance
tags, if you want to take a look.It also knows how to parse inline JSON, so it is very much a "do what you
mean" kind of input.
It works perfectly with a single item:
zfs:
state: present
name: ...
...
user_properties:
k: v
...
But I can’t find a way to iterate over it. Ideally, I’d like to write
something like:
zfs: {{ item }}
with_items: [{name: 'x', state: 'present', user_properties: {...}},
{name: 'y', state: 'present', mountpoint: '/path/to/mnt', ...} ]
When the property keys are variable but properties are all strings I can
write something like this:
module_name: state={{ item.state }}
name={{ item.name }}
{{ 'prop=%s' % item.prop if item.prop is defined else '' }}
...
I don’t like it, it’s verbose, and there’s probably a better way to do
it, but it works, if only with simple properties.
So my question becames how to iterate over a list of dictionaries,
possibily nested, with different keys?
Thanks a lot.
You can definitely pass in with_items with a list of hashes.
module_name: foo={{ item.name }} bar={{ item.value }}
with_items:
etc
or with_items: alist_of_hashes
etc
or as you have it, with
with_items: [ { name: ‘x’, value: ‘y’ }, { name: ‘a’, value: ‘b’ } ]
It seems like in your question instead of
zfs: {{ item }}
you might need to pass something more specific?
zfs: {{ item.zfs }}
??
am I misunderstanding the question ?
Michael DeHaan <michael@ansibleworks.com> writes:
You can definitely pass in with_items with a list of hashes.
module_name: foo={{ item.name }} bar={{ item.value }}
with_items:
- { name: 'x', value: 'y' }
- { name: 'a', value: 'b' }etc
or with_items: alist_of_hashes
etc
or as you have it, with
with_items: [ { name: 'x', value: 'y' }, { name: 'a', value: 'b' } ]
It seems like in your question instead of
zfs: {{ item }}
you might need to pass something more specific?
zfs: {{ item.zfs }}
??
am I misunderstanding the question ?
Maybe or, more probably, I can’t explain myself. 
Starting from your example, let’s add an attribute only in the second item:
module_name: foo={{ item.name }} bar={{ item.value }}
with_items:
- { name: 'x', value: 'y' }
- { name: 'a', value: 'b', extra: 'xtr' }
How should deal with it? Is adding
{{ 'extra=%s' % item.extra if item.extra is defined else '' }}
the preferred way?
Now let’s say that `extra` is a map:
module_name: foo={{ item.name }} bar={{ item.value }}
with_items:
- { name: 'x', value: 'y' }
- { name: 'a', value: 'b', extra: {k: 'v'} }
If I use the `defined` check shown above the module gets a string, I
believe.
I hope I didn’t mess up too much my argument
Giorgio Valoti <giorgio_v@me.com> writes:
Michael DeHaan <michael@ansibleworks.com> writes:
am I misunderstanding the question ?
Maybe or, more probably, I can’t explain myself.
Well, I guess I really can’t explain myself! 
No suggestions on this?
Thank you in advance.