Unable to define path variable in playbook

[yoshiwaan]

Issue Type:

Bug Report

Ansible Version:

[vagrant@localhost vagrant]$ ansible --version
/usr/lib64/python2.6/site-packages/Crypto/Util/number.py:57: PowmInsecureWarning: Not using mpz_powm_sec.  You should rebuild using libgmp >= 5 to avoid timing attack vulnerability.
  _warn("Not using mpz_powm_sec.  You should rebuild using libgmp >= 5 to avoid timing attack vulnerability.", PowmInsecureWarning)
ansible 2.0.1.0
  config file = /etc/ansible/ansible.cfg
  configured module search path = Default w/o overrides

Ansible Configuration:

Nothing

Environment:

CentOS 6.7 on Vagrant

Summary:

On previous versions of Ansible I would use a statement like the following in a playbook to define a global path change for a playbook run.

environment:
      PATH: "/usr/local/bin:{{ ansible_env.PATH }}"

In Ansible 2.0.1.0 this behaviour broke, which is supposedly 'working as intended' according to #14655.

Using the suggested fix from #14655 I changed my statement to:

environment:
      PATH: "/usr/local/bin:{{ (ansible_env|default({})).PATH|default('') }}"

Which is supposed to create a default initilisation of the variable if it's unset, so that things don't break in the setup task. However this causes issue for other modules, like yum.

Steps To Reproduce:

On a Centos or RHEL box:

testplay.yml

---
  - hosts: localhost
    connection: local
    environment:
      PATH: "/usr/local/bin:{{ (ansible_env|default({})).PATH|default('') }}"
    tasks:
      - name: yum update
        yum:
          name: '*'
          state: latest

Then run

sudo ansible-playbook -vvvv testplay.yml

If you comment out the PATH line then the play works.

Expected Results:

The yum module would run and update packages

Actual Results:

TASK [yum update] **************************************************************
task path: /vagrant/testplay.yml:8
ESTABLISH LOCAL CONNECTION FOR USER: vagrant
127.0.0.1 EXEC /bin/sh -c '( umask 22 && mkdir -p "` echo $HOME/.ansible/tmp/ansible-tmp-1457973532.38-261134906018159 `" && echo "` echo $HOME/.ansible/tmp/ansible-tmp-1457973532.38-261134906018159 `" )'
127.0.0.1 PUT /tmp/tmp2A3k_q TO /home/vagrant/.ansible/tmp/ansible-tmp-1457973532.38-261134906018159/yum
127.0.0.1 EXEC /bin/sh -c 'LANG=en_US.UTF-8 LC_ALL=en_US.UTF-8 LC_MESSAGES=en_US.UTF-8 PATH=/usr/local/bin:/usr/local/bin: /usr/bin/python -tt /home/vagrant/.ansible/tmp/ansible-tmp-1457973532.38-261134906018159/yum; rm -rf "/home/vagrant/.ansible/tmp/ansible-tmp-1457973532.38-261134906018159/" > /dev/null 2>&1'
An exception occurred during task execution. The full traceback is:
Traceback (most recent call last):
  File "/home/vagrant/.ansible/tmp/ansible-tmp-1457973532.38-261134906018159/yum", line 3795, in <module>
    main()
  File "/home/vagrant/.ansible/tmp/ansible-tmp-1457973532.38-261134906018159/yum", line 1028, in main
    disablerepo, disable_gpg_check, exclude, repoquery)
  File "/home/vagrant/.ansible/tmp/ansible-tmp-1457973532.38-261134906018159/yum", line 951, in ensure
    res = latest(module, pkgs, repoq, yum_basecmd, conf_file, en_repos, dis_repos)
  File "/home/vagrant/.ansible/tmp/ansible-tmp-1457973532.38-261134906018159/yum", line 762, in latest
    rc, out, err = module.run_command(yum_basecmd + ['check-update'])
  File "/home/vagrant/.ansible/tmp/ansible-tmp-1457973532.38-261134906018159/yum", line 2806, in run_command
    args = [ os.path.expandvars(os.path.expanduser(x)) for x in args ]
  File "/usr/lib64/python2.6/posixpath.py", line 251, in expanduser
    if not path.startswith('~'):
AttributeError: 'NoneType' object has no attribute 'startswith'

fatal: [localhost]: FAILED! => {"changed": false, "failed": true, "invocation": {"module_name": "yum"}, "parsed": false}

Any time the yum module invokes yum to install or upgrade a module I get this error with the suggested PATH settings above (if the current state of the yum package is correct then there's no error)

[bcoca]

try with this patch:

diff --git a/lib/ansible/module_utils/basic.py b/lib/ansible/module_utils/basic.py
index fe96472..ab0be36 100644
--- a/lib/ansible/module_utils/basic.py
+++ b/lib/ansible/module_utils/basic.py
@@ -1546,6 +1546,8 @@ class AnsibleModule(object):
             if p not in paths and os.path.exists(p):
                 paths.append(p)
         for d in paths:
+            if not d:
+                continue
             path = os.path.join(d, arg)
             if os.path.exists(path) and is_executable(path):
                 bin_path = path

[yoshiwaan]

Doesn't seem to make a difference for me. I'm on Centos and installed via epel yum package (/usr/lib/python2.6/site-packages/ansible/module_utils/basic.py) and pip (/usr/lib/python2.7/site-packages/ansible/module_utils/basic.py) on different systems. I made the patch to both and neither behaved differently using the test play I posted above.

I can't find anywhere else I could patch this so I'm guessing that's correct?

[yoshiwaan]

If it's not just me patching incorrectly then I've found out some more info.

I changed the test play to the following (with or without the patch it's the same):

---
  - hosts: localhost
    connection: local
    environment:
      PATH: "/usr/local/bin:{{ (ansible_env|default({})).PATH|default('') }}"
    tasks:
      - name: debug
        debug: var=ansible_env
      - name: yum update
        yum:
          name: '*'
          state: latest

and get this result from the debug output

ok: [localhost] => {
    "ansible_env": {
        "HOME": "/root",
        "HOSTNAME": "1ba8bda64185",
        "LANG": "en_US.UTF-8",
        "LC_ALL": "en_US.UTF-8",
        "LC_MESSAGES": "en_US.UTF-8",
        "LS_COLORS": "rs=0:di=01;34:ln=01;36:mh=00:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or=40;31;01:mi=01;05;37;41:su=37;41:sg=30;43:ca=30;41:tw=30;42:ow=34;42:st=37;44:ex=01;32:*.tar=01;31:*.tgz=01;31:*.arc=01;31:*.arj=01;31:*.taz=01;31:*.lha=01;31:*.lz4=01;31:*.lzh=01;31:*.lzma=01;31:*.tlz=01;31:*.txz=01;31:*.tzo=01;31:*.t7z=01;31:*.zip=01;31:*.z=01;31:*.Z=01;31:*.dz=01;31:*.gz=01;31:*.lrz=01;31:*.lz=01;31:*.lzo=01;31:*.xz=01;31:*.bz2=01;31:*.bz=01;31:*.tbz=01;31:*.tbz2=01;31:*.tz=01;31:*.deb=01;31:*.rpm=01;31:*.jar=01;31:*.war=01;31:*.ear=01;31:*.sar=01;31:*.rar=01;31:*.alz=01;31:*.ace=01;31:*.zoo=01;31:*.cpio=01;31:*.7z=01;31:*.rz=01;31:*.cab=01;31:*.jpg=01;35:*.jpeg=01;35:*.gif=01;35:*.bmp=01;35:*.pbm=01;35:*.pgm=01;35:*.ppm=01;35:*.tga=01;35:*.xbm=01;35:*.xpm=01;35:*.tif=01;35:*.tiff=01;35:*.png=01;35:*.svg=01;35:*.svgz=01;35:*.mng=01;35:*.pcx=01;35:*.mov=01;35:*.mpg=01;35:*.mpeg=01;35:*.m2v=01;35:*.mkv=01;35:*.webm=01;35:*.ogm=01;35:*.mp4=01;35:*.m4v=01;35:*.mp4v=01;35:*.vob=01;35:*.qt=01;35:*.nuv=01;35:*.wmv=01;35:*.asf=01;35:*.rm=01;35:*.rmvb=01;35:*.flc=01;35:*.avi=01;35:*.fli=01;35:*.flv=01;35:*.gl=01;35:*.dl=01;35:*.xcf=01;35:*.xwd=01;35:*.yuv=01;35:*.cgm=01;35:*.emf=01;35:*.axv=01;35:*.anx=01;35:*.ogv=01;35:*.ogx=01;35:*.aac=01;36:*.au=01;36:*.flac=01;36:*.mid=01;36:*.midi=01;36:*.mka=01;36:*.mp3=01;36:*.mpc=01;36:*.ogg=01;36:*.ra=01;36:*.wav=01;36:*.axa=01;36:*.oga=01;36:*.spx=01;36:*.xspf=01;36:",
        "PATH": "/usr/local/bin:",
        "PWD": "/root",
        "SHLVL": "3",
        "TERM": "xterm",
        "_": "/usr/bin/python"
    }
}

The path is set to what I set in the play and nothing else. It's never going to find the yum binary if that's the case, so somehow this error is also masking some sort of file not found error (or that error is just not implemented for yum).

The suggested work around posted in #14655 of using a zero initialised ansible_env.PATH clearly doesn't work. By changing the logic of the setup module to allow definition of environment variables and by forcing us to specify a default initialisation of the ansible_env.PATH variable if we want a non default it's breaking the default initialisation. This is clearly a bug.

Either the setup task needs to define facts before looking at the environment section of the play or perhaps this was just not a good change to make in the first place.

[zonca]

same issue here, using {{ (ansible_env|default({})).PATH|default('') }} at playbook level caused an error on the hostname module not being able to find the hostname command.

This workaround fixed that for me:
#14655 (comment)

[ansibot]

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[bcoca]

this was fixed via df5895e

[PickRelated]

@bcoca, looks like using {{ ansible_env.PATH }} erases everything else from PATH as of v2.3.1.0

- name: Echo path
  shell: echo $PATH
  environment:
    PATH: "/test:{{ ansible_env.PATH }}"

Results in /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games

Whereas

- name: Echo path
  shell: echo $PATH
  environment:
    PATH: "/test"

Results in /test
Any advise, please?

[eduardobaitello]

@PickRelated I was experiencing the same problem.

The reason was that I have the gather_facts disabled in my Playbook.
Enabling gather_facts and using PATH: "/usr/local/bin:{{ ansible_env.PATH }}" works fine.