Write slurped variable to a remote file in Ansible - ansible

I'm trying to figure out how one would copy or write the contents of a slurped variable to a remote (preferable) file. If this is not possible, what's the cleanest way to do it in steps?
I have something like this:
- name: Load r user public key
slurp:
src: *path*
register: slurped_r_key
- name: Decode r key
set_fact:
r_content: "{{ slurped_r_key.content | b64decode }}"
I want to get the contents of {{ r_content }} into a file in the remote machines that are part of an inventory group. If I cannot do that directly, what's the best way? Should I copy the contents to a local file and then scp the file over to the remote machines?
Thanks in advance!

To copy the variable to a file you can try as below:
- name: copy
copy:
content: "{{r_content}}"
dest: /tmp/testing

Related

How to substitute values to a conf file using Ansible

I have an ansible playbook that has created a file (/tmp/values.txt) in each server with the following content
1.1.1.1
2.2.2.2
3.3.3.3
4.4.4.4
5.5.5.5
And I have a conf file named etcd.conf in the /tmp/etcd.conf with the following content
and I need to substitute the value of each line from /tmp/values.txt, so /tmp/etcd.conf will look like this:
SELF_IP=1.1.1.1
NODE_1_IP=2.2.2.2
NODE_2_IP=3.3.3.3
NODE_3_IP=4.4.4.4
NODE_4_IP=5.5.5.5
Is there a way I can do this? I used the following lookup method but it only works in the controll server
- name: Create etcd.conf
template:
src: etcd.conf.j2
dest: /tmp/etcd.conf
vars:
my_values: "{{ lookup('file', '/tmp/values.txt').split('\n') }}"
my_vars: [SELF_IP, NODE_1_IP, NODE_2_IP, NODE_3_IP, NODE_4_IP]
my_dict: "{{ dict(my_vars|zip(my_values)) }}"
You can use the slurp: task to grab the content for each machine, or use command: cat /tmp/values.txt and then examine the stdout_lines of its register:-ed variable to achieve that same .split("\n") behavior (I believe you'll still need to use that .split call after | b64decode if you use the slurp approach)
What will likely require some massaging is that you'll need to identify the group (which may very well include all) of inventory hostnames for which that command will produce content, and then grab the hostvar out of them to get all values
Conceptually, similar to [ hostvars[hv].tmp_values.stdout_lines for hv in groups[the_group] ] | join("\n"), but it'll be tedious to write out, so I'd only want to do that if you aren't able to get it to work on your own

ansible-playbook gather information from a file

I want to read a file by ansible and find specific thing and store all of them in a file in my localhost
for example there is /tmp/test file in all host and I want to grep specific thing in this file and store all of them in my home.
What should I do?
There might be many ways to accomplish this. The choice of Ansible modules (or even tools) can vary.
One approach is (using only Ansible):
Slurp the remote file
Write new file with filtered content
Fetch the file to Control machine
Example:
- hosts: remote_host
tasks:
# Slurp the file
- name: Get contents of file
slurp:
src: /tmp/test
register: testfile
# Filter the contents to new file
- name: Save contents to a variable for looping
set_fact:
testfile_contents: "{{ testfile.content | b64decode }}"
- name: Write a filtered file
lineinfile:
path: /tmp/filtered_test
line: "{{ item }}"
create: yes
when: "'TEXT_YOU_WANT' in item"
with_items: "{{ testfile_contents.split('\n') }}"
# Fetch the file
- name: Fetch the filtered file
fetch:
src: /tmp/filtered_test
dest: /tmp/
This will fetch the file to /tmp/<ANSIBLE_HOSTNAME>/tmp/filtered_test.
You can use the Ansible fetch module to download files from the remote system to your local system. You can then do the processing locally, as shown in this Ansible cli example:
REMOTE=[YOUR_REMOTE_SERVER]; \
ansible -m fetch -a "src=/tmp/test dest=/tmp/ansiblefetch/" $REMOTE && \
grep "[WHAT_YOU_ARE_INTERESTED_IN]" /tmp/ansiblefetch/$REMOTE/tmp/test > /home/user/ansible_files/$REMOTE
This snippet runs the ad-hoc version of Ansible, calling the module fetch with the source folder (on the remote) and the destination folder (locally) as arguments. Fetch copies the file into a folder [SRC]/[REMOTE_NAME]/[DEST], from which we then grep what we are interested in, and output that in the /home/user/ansible_files/$REMOTE.

Ansible local_action example how does it work

How does the following Ansible play work:
- name: Generate join command
command: kubeadm token create --print-join-command
register: join_command
- name: Copy join command to local file
local_action: copy content="{{ join_command.stdout_lines[0] }}" dest="./join-command"
So as I understand, local_action is the same as delegate_to
but, copy content= did not make any sense. Isn't the actual command like "cp" need to be specified?
Take this example:
local_action: command ping -c 1 {{ inventory_hostname }}
Can we use something like this:
local_action: command cp content="{{ join_command.stdout_lines[0] }}" dest="./join-command"
So as I understand, local_action is the same as delegate_to ...
local_action is similar to delegate_to: localhost, but because local_action requires you to change the syntax of tasks, it's better to always use delegate_to. That is, while for a standard task, you might write:
- name: copy a file
copy:
src: myfile
dest: /path/to/myfile
And for a delegated task, you would use exactly the same syntax with the addition of the delegate_to line:
- name: copy a file
delegate_to: localhost
copy:
src: myfile
dest: /path/to/myfile
When using local_action you have to change the syntax of the task:
- name: copy a file
local_action:
module: copy
src: myfile
dest: /path/to/myfile
copy content= did not make any sense. Isn't the actual command like "cp" need to be specified?
No, copy is the name of an ansible module. You can see some examples of above, or just take a look at the documentation.
so looking at an example: local_action: command ping -c 1 {{ inventory_hostname }} Can we say:
local_action: command cp content="{{ join_command.stdout_lines[0] }}" dest="./join-command"
You should use delegate_to, and you should write it like this:
- delegate_to: localhost
copy:
content: "{{ join_command.stdout_lines[0] }}"
dest: ./join-command
Or if you actually want to run the cp command instead of the copy module, you would write something like:
- delegate_to: localhost
command: cp some_file another_file
That is simply running the standard cp command, which knows nothing about content= or dest=.
Hard to say what's the path to dest="./join-command". The full path works as expected.
For example:
dest="{{ playbook_dir }}/join-command"

How do I save an ansible variable into a temporary file that is automatically removed at the end of playbook execution?

In order to perform some operations locally (not on the remote machine), I need to put the content of an ansible variable inside a temporary file.
Please note that I am looking for a solution that takes care of generating the temporary file to a location where it can be written (no hardcoded names) and also that takes care of the removal of the file as we do not want to leave things behind.
You should be able to use the tempfile module, followed by either the copy or template modules. Like so:
- hosts: localhost
tasks:
# Create a file named ansible.{random}.config
- tempfile:
state: file
suffix: config
register: temp_config
# Render template content to it
- template:
src: templates/configfile.j2
dest: "{{ temp_config.path }}"
vars:
username: admin
Or if you're running it in a role:
- tempfile:
state: file
suffix: config
register: temp_config
- copy:
content: "{{ lookup('template', 'configfile.j2') }}"
dest: "{{ temp_config.path }}"
vars:
username: admin
Then just pass temp_config.path to whatever module you need to pass the file to.
It's not a great solution, but the alternative is writing a custom module to do it in one step.
Rather than do it with a file, why not just use the environment? This wan you can easily work with the variable and it will be alive through the ansible session and you can easily retrieve it in any steps or outside of them.
Although using the shell/application environment is probably, if you specifically want to use a file to store variable data you could do something like this
- hosts: server1
tasks:
- shell: cat /etc/file.txt
register: some_data
- local_action: copy dest=/tmp/foo.txt content="{{some_data.stdout}}"
- hosts: localhost
tasks:
- set_fact: some_data="{{ lookup('file', '/tmp/foo.txt') }}"
- debug: var=some_data
As for your requirement to give the file a unique name and clean it up at the end of the play. I'll leave that implementation to you

Ansible: Set variable to file content

I'm using the ec2 module with ansible-playbook I want to set a variable to the contents of a file. Here's how I'm currently doing it.
Var with the filename
shell task to cat the file
use the result of the cat to pass to the ec2 module.
Example contents of my playbook.
vars:
amazon_linux_ami: "ami-fb8e9292"
user_data_file: "base-ami-userdata.sh"
tasks:
- name: user_data_contents
shell: cat {{ user_data_file }}
register: user_data_action
- name: launch ec2-instance
local_action:
...
user_data: "{{ user_data_action.stdout }}"
I assume there's a much easier way to do this, but I couldn't find it while searching Ansible docs.
You can use lookups in Ansible in order to get the contents of a file, e.g.
user_data: "{{ lookup('file', user_data_file) }}"
Caveat: This lookup will work with local files, not remote files.
Here's a complete example from the docs:
- hosts: all
vars:
contents: "{{ lookup('file', '/etc/foo.txt') }}"
tasks:
- debug: msg="the value of foo.txt is {{ contents }}"
You can use the slurp module to fetch a file from the remote host: (Thanks to #mlissner for suggesting it)
vars:
amazon_linux_ami: "ami-fb8e9292"
user_data_file: "base-ami-userdata.sh"
tasks:
- name: Load data
slurp:
src: "{{ user_data_file }}"
register: slurped_user_data
- name: Decode data and store as fact # You can skip this if you want to use the right hand side directly...
set_fact:
user_data: "{{ slurped_user_data.content | b64decode }}"
You can use fetch module to copy files from remote hosts to local, and lookup module to read the content of fetched files.
lookup only works on localhost. If you want to retrieve variables from a variables file you made remotely use include_vars: {{ varfile }} . Contents of {{ varfile }} should be a dictionary of the form {"key":"value"}, you will find ansible gives you trouble if you include a space after the colon.

Resources