I am downloading the file with wget from ansible.
- name: Download Solr
shell: wget http://mirror.mel.bkb.net.au/pub/apache/lucene/solr/4.7.0/solr-4.7.0.zip
args:
chdir: {{project_root}}/solr
but I only want to do that if zip file does not exist in that location. Currently the system is downloading it every time.
Note: this answer covers general question of "How can i check the file existence in ansible", not a specific case of downloading file.
The problems with the previous answers using "command" or "shell" actions is that they won't work in --check mode. Actually, first action will be skipped, and next will error out on "when: solr_exists.rc != 0" condition (due to variable not being defined).
Since Ansible 1.3, there's more direct way to check for file existance - using "stat" module. It of course also works well as "local_action" to check a local file existence:
- local_action: stat path={{secrets_dir}}/secrets.yml
register: secrets_exist
- fail: msg="Production credentials not found"
when: secrets_exist.stat.exists == False
Unless you have a reason to use wget why not use get_url module. It will check if the file needs to be downloaded.
---
- hosts : all
gather_facts : no
tasks:
- get_url:
url="http://mirror.mel.bkb.net.au/pub/apache/lucene/solr/4.7.0/solr-4.7.0.zip"
dest="{{project_root}}/solr-4.7.0.zip"
NOTE: If you put the directory and not the full path in the dest ansible will still download the file to a temporary dir but do an md5 check to decide whether to copy to the dest dir.
And if you need to save state of download you can use:
---
- hosts : all
gather_facts : no
tasks:
- get_url:
url="http://mirror.mel.bkb.net.au/pub/apache/lucene/solr/4.7.0/solr-4.7.0.zip"
dest="{{project_root}}/solr-4.7.0.zip"
register: get_solr
- debug:
msg="solr was downloaded"
when: get_solr|changed
Many modules are already aware of the result and will be skipped if its already there, like file or geturl. Others like command have a creates option, which will skip this command if that file already exists (or doesn't exist, if you use the removes option).
So you should first check the available modules, if they are smart enough already. If not: I recommend the stats module. Advantage over the other solution: No "red errors but ignored" in the output.
- name: Check MySQL data directory existence
stat: path=/var/lib/mysql-slave
register: mysql_slave_data_dir
- name: Stop MySQL master to copy data directory
service: name=mysql state=stopped
sudo: yes
when: not mysql_slave_data_dir.stat.exists
There are at least two options here.
You can register a variable if the file exists, then use a when condition to execute the command on the condition that the file doesn't already exist:
- command: /usr/bin/test -e {{project_root}}/solr/solr-4.7.0.zip
register: solr_zip
ignore_errors: True
- name: Download Solr
shell: chdir={{project_root}}/solr /usr/bin/wget http://mirror.mel.bkb.net.au/pub/apache/lucene/solr/4.7.0/solr-4.7.0.zip
when: solr_zip|failed
You could also use the commands module with the creates option:
- name: Download Solr
command: /usr/bin/wget http://mirror.mel.bkb.net.au/pub/apache/lucene/solr/4.7.0/solr-4.7.0.zip chdir={{project_root}}/solr creates={{project_root}}/solr/solr-4.7.0.zip
This article might be useful
Out of it comes this example:
tasks:
- shell: if [[ -f "/etc/monitrc" ]]; then /bin/true; else /bin/false; fi
register: result
ignore_errors: True
- command: /bin/something
when: result|failed
- command: /bin/something_else
when: result|success
- command: /bin/still/something_else
when: result|skipped
So basically you can do this checking by registering a variable from a command and checking its return code. (You can also do this by checking its stdout)
- name: playbook
hosts: all
user: <your-user>
vars:
project_root: /usr/local
tasks:
- name: Check if the solr zip exists.
command: /usr/bin/test -e {{project_root}}/solr/solr-4.7.0.zip
ignore_errors: True
register: solr_exists
- name: Download Solr
shell: chdir={{project_root}}/solr wget http://mirror.mel.bkb.net.au/pub/apache/lucene/solr/4.7.0/solr-4.7.0.zip
when: solr_exists.rc != 0
This basically says that if the /usr/bin/test -e {{project_root}}/solr/solr-4.7.0.zip command returns a code that is not 0, meaning it doesn't exist then execute the task Download Solr
Hope it helps.
my favourite is to only download the file if it is newer than the local file (which includes when the local file does not exist)
the -N option with wget does this: https://www.gnu.org/software/wget/manual/html_node/Time_002dStamping-Usage.html .
sadly, i don't think there is an equivalent feature in get_url
so a very small change:
- name: Download Solr
shell: chdir={{project_root}}/solr wget -N http://<SNIPPED>/solr-4.7.0.zip
Use the creates argument
- name: Download Solr
shell: creates={{working_directory}}/solr/solr-4.7.0.zip chdir={{working_directory}}/solr wget http://mirror.mel.bkb.net.au/pub/apache/lucene/solr/4.7.0/solr-4.7.0.zip
Related
Im trying to perform an additional task on the output of stdout_lines.
Here is the playbook:
- name: Change to Splunk user
hosts:
sudo: yes
sudo_user: splunk
gather_facts: true
tasks:
- name: Run WGET & install SPLUNK
command: wget -O splunk-9.0.2-17e00c557dc1-Linux-x86_64.tgz https://download.splunk.com/products/splunk/releases/9.0.2/linux/splunk-9.0.2-17e00c557dc1-Linux-x86_64.tgz
- name: run 'ls' to get SPLUNK_PACKAGE_NAME
shell: 'ls -l'
register: command_output
- debug:
var: command_output.stdout_lines
I am using wget to download Splunk on the server and I need the Splunk package name so that I can extract the file in the next task.
For that, I tried to register ls -l as command_output.
Now, I need to untag it (tar xvzf splunk_package_name.tgz -C/opt), but I dont know how I can use the stdout_lines output in my tar command.
In Ansible, your use case should resume to one single task, using the unarchive module, along with the remote_src parameter set to true and the src one to your URL.
As described in the documentation:
If remote_src=yes and src contains ://, the remote machine will download the file from the URL first.
So, you end up with this single task:
- name: Install Splunk from remote archive
unarchive:
src: "https://download.splunk.com/products/splunk/releases/9.0.2\
/linux/splunk-9.0.2-17e00c557dc1-Linux-x86_64.tgz"
remote_src: true
## with this, you will end up with Splunk installed in /opt/splunk
dest: /opt
I've been searching for quite some time and tried many variants and similar answers without success. Hopefully this is something simple I am missing.
Ansible 2.9.6
I am creating many playbooks that all share a large set of custom Roles for my clients. I want to keep all logic out of the playbooks, and place that logic in the roles themselves to allow maximum re-usability. Basically, I just want to add boilerplate playbooks for simple "Role" runs via tags, with some vars overrides here and there.
My problem is that I can't seem to make some roles idempotent by using conditions - the conditionals don't work. The error I get is:
fatal: [localhost]: FAILED! => {"msg": "The conditional check 'homebrew_base.rc != 0' failed.
The error was: error while evaluating conditional (homebrew_bash.rc != 0): 'homebrew_bash' is undefined
The error appears to be in '/Users/eric/code/client1/provisioning/roles/bash/tasks/main.yaml': line 12, column 3, but may
be elsewhere in the file depending on the exact syntax problem.
The offending line appears to be:
- name: Change shell (chsh) for macOS to homebrew managed version
^ here
"}
Below is the boilerplate code for my playbooks:
# ./playbook.yaml
---
- name: Provisioning
hosts: localhost
connection: local
pre_tasks:
- include_vars: "{{ item }}"
with_fileglob:
- "{{ playbook_dir }}/vars/global.yaml"
tags: always
tasks:
- name: Use homebrew bash binary
include_role:
name: bash
tags: bash
The above is truncated quite a bit, but only thing missing are additional var files and a whole bunch of include_roles.
Below is my role file in the entirely though. They are largely untested because of the error I keep getting.
# ./roles/bash/tasks/main.yaml
---
- name: Check /etc/shells contains "/usr/local/bin/bash"
command: grep -Fxq "/usr/local/bin/bash" /etc/shells
register: homebrew_bash
ignore_errors: True
changed_when:
- homebrew_bash.rc != 0
- name: Check that homebrew installed /usr/local/bin/bash
stat:
path: /usr/local/bin/bash
register: homebrew_bash_binary
- name: Change shell (chsh) for macOS to homebrew managed versoin
tags: bash, chsh
shell: chsh -s /usr/local/bin/bash
become: yes
when:
- homebrew_bash.rc != 0
- homebrew_bash_binary.stat.exists = True
Ps: I do plan on abstracting those hardcoded paths into roles/bash/defaults/. But I need it working first before that.
Ps2: If there is a better way to use a contains filter (instead of the grep hack), I'm all ears.
I've tried:
making separate tasks/chsh.yaml, and using the include: command to call that task within the role. When I do this, I get an odd error telling me the variable is undefined - in the tasks/chsh.yaml - even though I am checking for the variable in tasks/main.yaml! That doesn't seem right.
using quotes in various places in the conditions
commenting out each condition: both give the same error, just differenet names.
Again, I am trying to keep this logic in the roles only - not in the playbook.
Thanks!
Figured it out. I was missing the "tags" on the conditionals!
# ./roles/bash/tasks/main.yaml
---
- name: Check /etc/shells contains "/usr/local/bin/bash"
tags: bash, chsh
command: grep -Fxq "/usr/local/bin/bash" /etc/shells
register: homebrew_bash
ignore_errors: True
changed_when:
- homebrew_bash.rc != 0
- name: Check that homebrew installed /usr/local/bin/bash
tags: bash, chsh
stat:
path: /usr/local/bin/bash
register: homebrew_bash_binary
- name: Change shell (chsh) for macOS to homebrew managed versoin
tags: bash, chsh
shell: chsh -s /usr/local/bin/bash
become: yes
when:
- homebrew_bash.rc != 0
- homebrew_bash_binary.stat.exists = True
I'm very new to Ansible
Is it possible to check if a string exists in a file using Ansible.
I want to check is a user has access to a server.
this can be done on the server using cat /etc/passwd | grep username
but I want Ansible to stop if the user is not there.
I have tried to use the lineinfile but can't seem to get it to return.
code
- name: find
lineinfile: dest=/etc/passwd
regexp=[user]
state=present
line="user"
The code above adds user to the file if he is not there. All i want to do is check. I don't want to modify the file in any way, is this possible
Thanks.
It's a tricky one. the lineinfile module is specifically intended for modifying the content of a file, but you can use it for a validation check as well.
- name: find
lineinfile:
dest: /etc/passwd
line: "user"
check_mode: yes
register: presence
failed_when: presence.changed
check_mode ensures it never updates the file.
register saves the variable as noted.
failed_when allows you to set the failure condition i.e. by adding the user because it was not found in the file.
There are multiple iterations of this that you can use based on what you want the behavior to be. lineinfile docs particular related to state and regexp should allow you to determine whether or not presence or absence is failure etc, or you can do the not presence.changed etc.
I'd probably register and evaluate a variable.
The following simple playbook works for me:
- hosts: localhost
tasks:
- name: read the passwd file
shell: cat /etc/passwd
register: user_accts
- name: a task that only happens if the user exists
when: user_accts.stdout.find('hillsy') != -1
debug: msg="user hillsy exists"
If you want to fail if there is no user:
tasks:
- shell: grep username /etc/passwd
changed_when: false
By default shell module will fail if command exit code is non zero.
So it will give you ok if username is there and fails otherwise.
I use changed_when: false to prevent changed state when grepping.
I am using the following approach, using only a grep -q and a registered variable.
Upside is that it's simple, downside is that you have a FAILED line in your output. YMMV.
- name: Check whether foobar is defined in /bar/baz
command:
cmd: 'grep -q foobar /bar/baz'
register: foobar_in_barbaz
changed_when: false
ignore_errors: true
- when: not foobar_in_barbaz.failed
name: Do something when foobar is in /bar/baz
....
- when: foobar_in_barbaz.failed
pause:
seconds: 1
content: |
You do not seem to have a foobar line in /bar/baz
If you add it, then magic stuff will happen!
I have to check whether a file exists in /etc/. If the file exists then I have to skip the task.
Here is the code I am using:
- name: checking the file exists
command: touch file.txt
when: $(! -s /etc/file.txt)
You can first check that the destination file exists or not and then make a decision based on the output of its result:
tasks:
- name: Check that the somefile.conf exists
stat:
path: /etc/file.txt
register: stat_result
- name: Create the file, if it doesnt exist already
file:
path: /etc/file.txt
state: touch
when: not stat_result.stat.exists
The stat module will do this as well as obtain a lot of other information for files. From the example documentation:
- stat: path=/path/to/something
register: p
- debug: msg="Path exists and is a directory"
when: p.stat.isdir is defined and p.stat.isdir
This can be achieved with the stat module to skip the task when file exists.
- hosts: servers
tasks:
- name: Ansible check file exists.
stat:
path: /etc/issue
register: p
- debug:
msg: "File exists..."
when: p.stat.exists
- debug:
msg: "File not found"
when: p.stat.exists == False
In general you would do this with the stat module. But the command module has the creates option which makes this very simple:
- name: touch file
command: touch /etc/file.txt
args:
creates: /etc/file.txt
I guess your touch command is just an example? Best practice would be to not check anything at all and let ansible do its job - with the correct module. So if you want to ensure the file exists you would use the file module:
- name: make sure file exists
file:
path: /etc/file.txt
state: touch
Discovered that calling stat is slow and collects a lot of info that is not required for file existence check.
After spending some time searching for solution, i discovered following solution, which works much faster:
- raw: test -e /path/to/something && echo -n true || echo -n false
register: file_exists
- debug: msg="Path exists"
when: file_exists.stdout == "true"
You can use Ansible stat module to register the file, and when module to apply the condition.
- name: Register file
stat:
path: "/tmp/test_file"
register: file_path
- name: Create file if it doesn't exists
file:
path: "/tmp/test_file"
state: touch
when: file_path.stat.exists == False
Below is the ansible play which i used to remove the file if the file exists on OS end.
- name: find out /etc/init.d/splunk file exists or not'
stat:
path: /etc/init.d/splunk
register: splunkresult
tags:
- always
- name: 'Remove splunk from init.d file if splunk already running'
file:
path: /etc/init.d/splunk
state: absent
when: splunkresult.stat.exists == true
ignore_errors: yes
tags:
- always
I have used play condition as like below
when: splunkresult.stat.exists == true --> Remove the file
you can give true/false based on your requirement
when: splunkresult.stat.exists == false
when: splunkresult.stat.exists == true
I find it can be annoying and error prone to do a lot of these .stat.exists type checks. For example they require extra care to get check mode (--check) working.
Many answers here suggest
get and register
apply when register expression is true
However, sometimes this is a code smell so always look for better ways to use Ansible, specifically there are many advantages to using the correct module. e.g.
- name: install ntpdate
package:
name: ntpdate
or
- file:
path: /etc/file.txt
owner: root
group: root
mode: 0644
But when it is not possible use one module, also investigate if you can register and check the result of a previous task. e.g.
# jmeter_version: 4.0
- name: Download Jmeter archive
get_url:
url: "http://archive.apache.org/dist/jmeter/binaries/apache-jmeter-{{ jmeter_version }}.tgz"
dest: "/opt/jmeter/apache-jmeter-{{ jmeter_version }}.tgz"
checksum: sha512:eee7d68bd1f7e7b269fabaf8f09821697165518b112a979a25c5f128c4de8ca6ad12d3b20cd9380a2b53ca52762b4c4979e564a8c2ff37196692fbd217f1e343
register: download_result
- name: Extract apache-jmeter
unarchive:
src: "/opt/jmeter/apache-jmeter-{{ jmeter_version }}.tgz"
dest: "/opt/jmeter/"
remote_src: yes
creates: "/opt/jmeter/apache-jmeter-{{ jmeter_version }}"
when: download_result.state == 'file'
Note the when: but also the creates: so --check doesn't error out
I mention this because often these less-than-ideal practices come in pairs i.e. no apt/yum package so we have to 1) download and 2) unzip
Hope this helps
I use this code and it works fine for folders and files. Just make sure there is no trailing spaces after the folder name. If folder exists , the file_exists.stdout will be "true" otherwise it will just be an empty string ""
- name: check filesystem existence
shell: if [[ -d "/folder_name" ]]; then echo "true"; fi
register: file_exists
- name: debug data
debug:
msg: "Folder exists"
when: file_exists.stdout == "true"
vars:
mypath: "/etc/file.txt"
tasks:
- name: checking the file exists
command: touch file.txt
when: mypath is not exists
A note on relative paths to complement the other answers.
When doing infrastructure as code I'm usually using roles and tasks that accept relative paths, specially for files defined in those roles.
Special variables like playbook_dir and role_path are very useful to create the absolute paths needed to test for existence.
You can use shell commands to check if file exists
- set_fact:
file: "/tmp/test_file"
- name: check file exists
shell: "ls {{ file }}"
register: file_path
ignore_errors: true
- name: create file if don't exist
shell: "touch {{ file }}"
when: file_path.rc != 0
I'm currently developing ansible script to build and deploy java project.
so, I can set the log_path like below
log_path=/var/log/ansible.log
but, It is hard to look up build history.
Is it possible to append datetime to log file name?
for example,
ansible.20150326145515.log
I don't believe there is a built-in way to generate the date on the fly like that but one option you have is to use a lookup which can shell out to date. Example:
log_path="/var/log/ansible.{{ lookup('pipe', 'date +%Y%m%d%H%M%S') }}.log"
Here is an option using ANSIBLE_LOG_PATH environment variable thanks to Bash shell alias:
alias ansible="ANSIBLE_LOG_PATH=ansible-\`date +%Y%m%d%H%M%S\`.log ansible"
Feel free to use an absolute path if you prefer.
I found it.
just add task to copy(or mv command) log locally
- name: Copy ansible.log
connection: local
command: mv ./logs/ansible.log ./logs/ansible.{{ lookup('pipe', 'date %Y%M%d%H%M%S') }}.log
run_once: true
thanks to #jarv
How about this:
- shell: date +%Y%m%d%H%M%S
register: timestamp
- debug: msg="foo.{{timestamp.stdout}}.log"
Output:
TASK [command] *****************************************************************
changed: [blabla.example.com]
TASK [debug] *******************************************************************
ok: [blabla.example.com] => {
"msg": "foo.20160922233847.log"
}
According to the nice folks at the #ansible freenode IRC, this can be accomplished with a custom callback plugin.
I haven't done it yet because I can't install the Ansible Python library on this machine. Specifically, Windows 7 can't have directory names > 260 chars in length, and pip tries to make lengthy temporary paths. But if someone gets around to it, please post it here.
Small improvement on #ickhyun-kwon answer:
- name: "common/_ansible_log_path.yml: rename ansible.log"
connection: local
shell: |
mkdir -vp {{ inventory_dir }}/logs/{{ svn_deploy.release }}/ ;
mv -vf {{ inventory_dir }}/logs/ansible.log {{ inventory_dir }}/logs/{{ svn_deploy.release }}/ansible.{{ svn_deploy.release }}.{{ lookup('pipe', 'date +%Y-%m-%d-%H%M') }}.log args:
executable: /bin/bash
chdir: "{{ inventory_dir }}"
run_once: True
ignore_errors: True
This has separate log directories per svn release, ensures the log directory actually exists before the mv command.
Ansible interprets ./ as the current playbook directory, which may or may not be the root of your ansible repository, whereas mine live in ./playbooks/$project/$role.yml. For me {{ inventory_dir }}/logs/ happens to correspond to the ~/ansible/log/ directory, though alternative layout configurations do not guarantee this.
I am unsure the correct way to formally extract the absolute ansible.cfg::log_path variable
Also the date command for month is +%m and not %M which is Minute
I have faced a similar problem while trying to set dynamic log paths for various playbooks.
A simple solution seems to be to pass the log filename dynamically to the ANSIBLE_LOG_PATH environment variable. Checkout -> https://docs.ansible.com/ansible/latest/reference_appendices/config.html
In this particular case just export the environment variable when running the intended playbook on your terminal:
export ANSIBLE_LOG_PATH=ansible.`date +%s`.log; ansible-playbook test.yml
Else if the intended filename cannot be generated by the terminal, you can always use a runner playbook which runs the intended playbook from the within:
---
- hosts:
- localhost
gather_facts: false
ignore_errors: yes
tasks:
- name: set dynamic variables
set_fact:
task_name: dynamic_log_test
log_dir: /path/to/log_directory/
- name: Change the working directory and run the ansible-playbook as shell command
shell: "export ANSIBLE_LOG_PATH={{ log_dir }}log_{{ task_name|lower }}.txt; ansible-playbook test.yml"
register: shell_result
This should log the result of test.yml to /path/to/log_directory/log_dynamic_log_test.txt
Hope you find this helpful!