Utilizing timestamps within filenames

[Joe_Louthan]

Hello,

In my deployments, I tend to do db backups and dump them into filenames containing a timestamp like so:

mysqldump dbname | gzip -9c > ~/dbname.date +%Y-%m-%d.%H%M.sql.gz ; ls -la ~/ | grep date +%Y-%m-%d`

`

As you can see, when the dump is done, I want to see the resulting file just to eyeball it and make everything looks right.

(To answer future questions: we date time stamp our backup files so that we can keep them for an extended period of time.)

I would like to write something like this:

`

• hosts: dbserver
  remote_user: jlouthan
  tasks:

• name: Backup Prod Database
  shell: mysqldump dbdump | gzip -9c > ~jlouthan/dbdump.date +%Y-%m-%d.sql.gz
  become: yes
  become_method: sudo

• name: Check to see if the dbdump has been successfully created
  wait_for: path=~jlouthan/dbdump.date +%Y-%m-%d.sql.gz

`

Is there any chance that Ansible would be able to pick up on backticks or is there a better way?

[felixfontein]

Hi Joe,

you could add a task

- name: Get current timestamp
  local_action: command bash -c "date +%Y-%m-%d.%H%M"
  register: now
  run_once: true

(or something similar adapted to your local environment) before your
dump task and then use {{ now }} in the next tasks to always get the
same timestamp.

Best,
Felix

[Brian_Coca]

You can use a lookup or create a var based on it:

​datestring: ​"{{lookup(‘pipe’, “date +%Y-%m-%d.%H%M”)}}"

[Johannes_Kastl]

Apart form the other answers, I avoid using backticks and use the
$(date ...) syntax instead (a leading dollar sign and brackets instead
of backticks). Have you tried this?

Johannes

[Brian_Coca]

$() depends on shell, I prefer it as it is stackable and cleaner than the backticks, but not always available.

[Joe_Louthan]

I ran this:

`

• hosts: dbserver
  remote_user: jlouthan
  tasks:

• name: Get current timestamp
  local_action: command bash -c “date +%Y-%m-%d.%H%M”
  register: timestamp
  run_once: true

• debug: var=timestamp.stdout

• name: Get current datestamp
  local_action: command bash -c “date +%Y-%m-%d”
  register: datestamp
  run_once: true

• debug: var=datestamp.stdout

• name: Backup Stag Database
  mysql_db: state=dump name=dbname target=~jlouthan/dbname.{{ datestamp }}.sql
  become: yes
  become_method: sudo

• name: See the the Stag DB backup
  shell: ls -la ~jlouthan/ | grep {{ timestamp }}
  register: dumpstag

• debug: var=dumpstag.stdout_lines

• name: Make sure that the Stag DB Backups look good before you continue
  pause:

`

And got this:

`

[jlouthan@ansible-server Playbooks]$ ansible-playbook test-backup-Client-staging-db.yml
SUDO password:

PLAY [dbserver] **************************************************************

GATHERING FACTS ***************************************************************

ok: [dbserver]

TASK: [Get current timestamp] *************************************************
changed: [dbserver → 127.0.0.1]

TASK: [debug var=timestamp.stdout] ********************************************
ok: [dbserver] => {
“var”: {
“timestamp.stdout”: “2016-04-22.1507”
}
}

TASK: [Get current datestamp] *************************************************
changed: [dbserver → 127.0.0.1]

TASK: [debug var=datestamp.stdout] ********************************************
ok: [dbserver] => {
“var”: {
“datestamp.stdout”: “2016-04-22”
}
}

TASK: [Backup Stag Database] **************************************************
failed: [dbserver] => {“failed”: true}
msg: this module requires key=value arguments ([‘state=dump’, ‘name=dbname’, ‘target=~jlouthan/dbname.{changed:’, ‘True,’, ‘end:’, ‘2016-04-22 15:07:30.816204,’, ‘stdout:’, ‘2016-04-22,’, ‘cmd:’, ‘[bash,’, ‘-c,’, ‘date +%Y-%m-%d],’, ‘rc:’, ‘0,’, ‘start:’, ‘2016-04-22 15:07:30.810278,’, ‘stderr:’, ‘,’, ‘delta:’, ‘0:00:00.005926,’, ‘invocation:’, ‘{module_name:’, ‘ucommand,’, ‘module_complex_args:’, ‘{},’, ‘module_args:’, ‘ubash -c “date +%Y-%m-%d”},’, ‘stdout_lines:’, ‘[2016-04-22],’, ‘warnings:’, ‘}.sql’])

FATAL: all hosts have already failed – aborting

PLAY RECAP ********************************************************************
to retry, use: --limit @/home/jlouthan/test-backup-Client-staging-db.retry

dbserver : ok=5 changed=2 unreachable=0 failed=1

`

What am I doing wrong?

[Brian_Coca]

that the module name in the error is ‘ucommand’ and the spacing you posted, lends me to believe you are not matching the error to the actual play.

[felixfontein]

Hi Joe,

I ran this:
- hosts: dbserver
  remote_user: jlouthan
  tasks:
      - name: Get current timestamp
        local_action: command bash -c "date +%Y-%m-%d.%H%M"
        register: timestamp
        run_once: true

      - debug: var=timestamp.stdout

as you correctly note here, the variable you need is not timestamp, but
timestamp.stdout.

(I forgot the .stdout in my original mail.)

      - name: Backup Stag Database
        mysql_db: state=dump name=dbname target=~jlouthan/dbname.{{
datestamp }}.sql

Here you have to write {{ datestamp.stdout }} instead of
{{ datestamp }}; otherwise, instead of just the datestamp, the whole
dict will be appended, which results in the error message you get below.

TASK: [Backup Stag Database]
**************************************************
failed: [dbserver] => {"failed": true}
msg: this module requires key=value arguments (['state=dump',
'name=dbname', 'target=~jlouthan/dbname.{changed:', 'True,', 'end:',
'2016-04-22 15:07:30.816204,', 'stdout:', '2016-04-22,', 'cmd:',
'[bash,', '-c,', 'date +%Y-%m-%d],', 'rc:', '0,', 'start:',
'2016-04-22 15:07:30.810278,', 'stderr:', ',', 'delta:',
'0:00:00.005926,', 'invocation:', '{module_name:', 'ucommand,',
'module_complex_args:', '{},', 'module_args:', 'ubash -c "date
+%Y-%m-%d"},', 'stdout_lines:', '[2016-04-22],', 'warnings:',
'}.sql'])

Here you can see that {{ datestamp }} was replaced by:

{changed:', 'True,', 'end:', '2016-04-22 15:07:30.816204,', 'stdout:',
'2016-04-22,', 'cmd:', '[bash,', '-c,', 'date +%Y-%m-%d],', 'rc:',
'0,', 'start:', '2016-04-22 15:07:30.810278,', 'stderr:', ',',
'delta:', '0:00:00.005926,', 'invocation:', '{module_name:',
'ucommand,', 'module_complex_args:', '{},', 'module_args:', 'ubash -c
"date +%Y-%m-%d"}

which is NOT what you want

Best,
Felix

[Joe_Louthan]

That’s it! Thank you!

To avoid being “that guy”, here is the working playbook:

`

[sivel]

Also, just as an FYI, this can be achieved without calling the date command: