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##### SUMMARY

Our ansible.cfg lists all well-known keys, but ansible-vault fails to run if any of the keys are missing. We only publish to our CI/respective user environments keys that are appropriate for that stack. This means that an operations person cannot run ansible without having access to all known environment's keys. To us, this makes the use of multiple vault ids not all that useful.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
ansible-vault

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```
ansible 2.7.10
  config file = /Users/dkimsey/ansible/ansible.cfg
  configured module search path = ['/Users/dkimsey/ansible/library']
  ansible python module location = /Users/dkimsey/.virtualenvs/ansible-2.7/lib/python3.7/site-packages/ansible
  executable location = /Users/dkimsey/.virtualenvs/ansible-2.7/bin/ansible
  python version = 3.7.3 (default, May  1 2019, 10:48:04) [Clang 10.0.0 (clang-1000.11.45.5)]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```
DEFAULT_VAULT_IDENTITY_LIST(/Users/dkimsey/ansible/ansible.cfg) = ['qa@~/.vault-qa', 'stg@~/.vault-staging', 'prod@~/.vault-production']
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->

n/a


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```
$ echo "my-secret-key" > ~/.vault-staging
$ ansible-vault encrypt_string --vault-id=stg --name client
```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->

I'd expect it to skip missing vault keys. Maybe log it in verbose mode that it tried to access and failed.

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```
ansible-vault 2.7.10
  config file = /Users/dkimsey/ansible/ansible.cfg
  configured module search path = ['/Users/dkimsey/ansible/library']
  ansible python module location = /Users/dkimsey/.virtualenvs/ansible-2.7/lib/python3.7/site-packages/ansible
  executable location = /Users/dkimsey/.virtualenvs/ansible-2.7/bin/ansible-vault
  python version = 3.7.3 (default, May  1 2019, 10:48:04) [Clang 10.0.0 (clang-1000.11.45.5)]
Using /Users/dkimsey/ansible/ansible.cfg as config file
ERROR! The vault password file /Users/dkimsey/.vault-qa was not found
```

''' code behind bin/ansible* programs '''
    PAGER = 'less'
    
    
    LESS_OPTS = 'FRSX'
    SKIP_INVENTORY_DEFAULTS = False
    def __init__(self, args, callback=None):
        """
        Base init method for all command line programs
        """
        if not args:
            raise ValueError('A non-empty list for args is required')
        self.args = args
        self.parser = None
        self.callback = callback
        if C.DEVEL_WARNING and __version__.endswith('dev0'):
            display.warning(
                'You are running the development version of Ansible. You should only run Ansible from "devel" if '
                'you are modifying the Ansible engine, or trying out features under development. This is a rapidly '
                'changing source of code and can become unstable at any point.'
            )
    @abstractmethod
    def run(self):