Ansible Store command s stdout in new variable

Question

Inside my playbook I d like to create a variable holding the output of an external command  Afterwards I want to make use of that variable in a couple of templates     Here are the relevant parts of the playbook     tasks      - name  Create variable from command       command   echo Hello        register  command output     - debug  msg    command output stdout         - name  Copy test service       template  src    templates test service j2 dest  tmp test service     - name  Enable test service       shell  systemctl enable  tmp test service     - name  Start test service       shell  systemctl start test service   and let s say this is my template    Unit  Description MyApp After docker service Requires docker service   Service  TimeoutStartSec 0 ExecStartPre - usr bin docker kill busybox1 ExecStartPre - usr bin docker rm busybox1 ExecStartPre  usr bin docker pull busybox ExecStart  usr bin docker run --name busybox1 busybox  bin sh -c  while true  do echo    string to echo     sleep 1  done    Install  WantedBy multi-user target    Notice the    string to echo      So what I m basically looking for is a way to store the contents of command output stdout  which is generated retrieved during the first task  in a new variable string to echo  That variable I d like to use in multiple templates afterwards     I guess I could just use   command output stdout   in my templates  but I want to get rid of that  stdout for readability

User · Answer

In case than you want to store a complex command to compare text result  for example to compare the version of OS  maybe this can help you   tasks         - shell  echo   cat  etc issue   awk   print  7             register  echo content         - shell  echo  It works           when  echo content stdout     12           register  out        - debug  var out stdout lines

User · Answer

I m a newbie in Ansible  but I would suggest next solution   playbook yml      vars    command output full      stdout  will be overriden below   command output     command output full stdout                tasks    - name  Create variable from command     command   echo Hello      register  command output full   - debug  msg     command output       It should work  and works for me  because Ansible uses lazy evaluation  But it seems it checks validity before the launch  so I have to define command output full stdout in vars   And  of course  if it is too many such vars in vars section  it will look ugly

User · Answer

If you want to go further and extract the exact information you want from the Playbook results  use JSON query language like jmespath  an example     - name  Sample Playbook        Fill up your task     no log  True     register  example output    - name  Json Query     set fact        query result          example output     example output   json query  results    name

User · Answer

You have to store the content as a fact   - set fact      string to echo      command output stdout

User · Answer

There s no need to set a fact       - shell  cat  hello        register  cat contents      - shell  echo  I cat hello        when  cat contents stdout     hello

User · Answer

A slight modification beyond  udondan s answer  I like to reuse the registered variable names with the set fact to help keep the clutter to a minimum   So if I were to register using the variable  psk  I d use that same variable name with creating the set fact   Example  - name  generate PSK   shell  openssl rand -base64 48   register  psk   delegate to  127 0 0 1   run once  true  - set fact       psk    psk stdout     - debug  var psk   run once  true   Then when I run it     ansible-playbook -i inventory setup ipsec yml   PLAY                                                                                                                                                                                 all                                                                                                                                                                              TASK  Gathering                                                                                                                                                                     Facts                                                                                                                                                                 ok   hostc mydom com   ok   hostb mydom com   ok   hosta mydom com    TASK  libreswan   generate                                                                                                                                                          PSK                                                                                                                                                        changed   hosta mydom com - gt  127 0 0 1    TASK  libreswan                                                                                                                                                                     set fact                                                                                                                                                            ok   hosta mydom com   ok   hostb mydom com   ok   hostc mydom com    TASK  libreswan                                                                                                                                                                     debug                                                                                                                                                               ok   hosta mydom com    gt          psk    6Tx 4CPBa1xmQ9A6yKi7ifONgoYAXfbo50WXPc1kGcird7u pVso vQtz WdBIvo       PLAY                                                                                                                                                                                RECAP                                                                                                                                                                            hosta mydom com      ok 4    changed 1    unreachable 0    failed 0  hostb mydom com      ok 2    changed 0    unreachable 0    failed 0  hostc mydom com      ok 2    changed 0    unreachable 0    failed 0

[ansible] Ansible: Store command's stdout in new variable?

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