How to use ansible loop - loops

Question

Variable file
I have a variable file
fruits:
- apple
- banana
- orange
- strawberry
- grapes
- papaya
users:
- user_name: 'john'
user_age: 45
- user_name: 'yash'
user_age: 95
- user_name: 'srk'
user_age: 52
- user_name: 'alia'
user_age: 26
Playbook Tasks
and my ansible tasks, just trying to make a text file and adding variables in file in vertical order.
- hosts: localhost
gather_facts: true
vars_files:
- variables.var # this is my variable file in the same dir that playbook have.
tasks:
- name: add fruits to the list
lineinfile:
create: yes
line: "{{ item }}"
path: /home/ansible/ansible-demo2/fruits.txt
loop:
- "{{ fruits|flatten }}"
- name: add uses to the list
lineinfile:
create: yes
line: "{{ item.user_name }} ==> {{ item.user_age }}"
path: /home/ansible/ansible-demo2/users.txt
loop:
- "{{ users|flatten(levels=1) }}"
Errors
But I am getting weird behavior. Below is the output of fruits task and error of the users task.
TASK [add fruits to the list] ***************************************************************************************************************************
ok: [localhost] => (item=[u'apple', u'banana', u'orange', u'strawberry', u'grapes', u'papaya'])
[WARNING]: The value ['apple', 'banana', 'orange', 'strawberry', 'grapes', 'papaya'] (type list) in a string field was converted to u"['apple',
'banana', 'orange', 'strawberry', 'grapes', 'papaya']" (type string). If this does not look like what you expect, quote the entire value to ensure it
does not change.
TASK [add uses to the list] *****************************************************************************************************************************
fatal: [localhost]: FAILED! => {"msg": "The task includes an option with an undefined variable. The error was: 'list object' has no attribute 'user_name'
\n\nThe error appears to be in '/home/ansible/ansible-demo2/myansible.yml': line 18, column 7, but may\nbe elsewhere in the file depending on the exact s
yntax problem.\n\nThe offending line appears to be:\n\n\n - name: add uses to the list\n ^ here\n"}
Expected Output
List in vertical order in text file.
Comment on question:
I am amazed every thing works fine with with_items and not with loop, even user_name variable is defined but still it is saying undefined. Now I unable to find out what's wrong going on.
Reference:
Here is the doc that I am referencing : Migrating from with_X to loop
Edit: Variables debug output
I debug the variables. output is below
TASK [debug] ********************************************************************************************************************************************
ok: [localhost] => {
"fruits": [
"apple",
"banana",
"orange",
"strawberry", "grapes", "papaya"
]
}
TASK [debug] ********************************************************************************************************************************************
ok: [localhost] => {
"users": [
{
"user_age": 45,
"user_name": "john"
},
{
"user_age": 95,
"user_name": "yash"
},
{
"user_age": 52,
"user_name": "srk"
},
{
"user_age": 26,
"user_name": "alia"
}
]
}

Answer 1

Q: *"[WARNING]: The value ['apple', ... ] (type list) in a string field was converted to u"['apple', ... ]" (type string).
A: From the code, it's not clear what is the reason for this conversion. The data and the playbook below work as expected.
shell> cat data.yml
fruits:
- apple
- banana
- orange
- strawberry
- grapes
- papaya
users:
- user_name: 'john'
user_age: 45
- user_name: 'yash'
user_age: 95
- user_name: 'srk'
user_age: 52
- user_name: 'alia'
user_age: 26
shell> cat playbook.yml
- hosts: localhost
vars_files:
- data.yml
tasks:
- name: add fruits to the list
lineinfile:
create: yes
line: "{{ item }}"
path: fruits.txt
loop: "{{ fruits }}"
- name: add uses to the list
lineinfile:
create: yes
line: "{{ item.user_name }} ==> {{ item.user_age }}"
path: users.txt
loop: "{{ users }}"
Give
shell> cat fruits.txt
apple
banana
orange
strawberry
grapes
papaya
shell> cat users.txt
john ==> 45
yash ==> 95
srk ==> 52
alia ==> 26
Q: "2 variables fruits1 and fruits2 ... append their data into single file ... in single task with 2 vars"
A: With the modified data
shell> cat data.yml
fruits1:
- apple
- banana
- orange
fruits2:
- strawberry
- grapes
- papaya
this task gives the same result
- name: add fruits to the list
lineinfile:
create: yes
line: "{{ item }}"
path: fruits.txt
loop: "{{ fruits1 + fruits2 }}"
See Append list variable to another list in Ansible.
Comment on the question: "I am amazed everything works fine with with_items and not with loop"
A: See Comparing loop and with_*.