Overview

The ploy_ansible plugin provides integration of Ansible with ploy. It automatically builds an inventory and provides a custom connection plugin.

Installation

ploy_ansible is best installed with easy_install, pip or with zc.recipe.egg in a buildout.

Commands

The plugin adds the following commands to ploy.

configure

Configures an instance. There are three ways to specify how to configure an instance. Applying the roles given by the roles option of an instance, a playbook set by the playbook option or a playbook with the unique name of the instance found in the playbooks-directory. Using roles or a playbook is mutually exclusive. If you specify a playbook and there is also a playbook in the default location, you will get a warning.

inventory

Lists all known groups and their associated hosts, including regular default groups, such as all but also implicit, ploy_ansible groups such as instances of a particular master (i.e. all ez-instances of an ez-master)

ansible

Runs an Ansible command. This basically reflects the ansible script of Ansible.

playbook

Applies a playbook. This basically reflects the ansible-playbook script of Ansible.

vault

Manages file encryption. This basically reflects the ansible-vault script of Ansible, but handles the encryption key source via ploy.conf.

vault-key

Manages the vault key.

Options

Global

playbooks-directory

The playbooks-directory option of the ansible section allows you to specify the directory where playbooks, roles, host_vars etc are looked up. If you specify a relative path, then it's always relative to the ploy.conf directory. If you have a structure like this:

project
|-- deployment
| |-- roles
| |-- host_vars
|
|-- etc
  |-- ploy.conf

Then you would put the following into your ploy.conf:

[ansible]
playbooks-directory = ../deployment

By default it is set to the parent directory of the directory the ploy.conf is located at like this:

project
|-- roles
|-- host_vars
|-- etc
  |-- ploy.conf

vault-password-source

Using the keyring library, you can store the encryption key for the Ansible vault in your keychain.

The vault-password-source option is the id used in your keychain. The id must be unique among all people who have to use the feature, as it is used as an identifier in their keychain. If in doubt, use a speaking prefix and add a guid by running python -c "import uuid; print(uuid.uuid4().hex)".

If you want to rekey your files, you have to put the old id into the vault-password-old-source option and set a new id in vault-password-source. Just incrementing a number or appending a new guid is best.

Example:

[ansible]
vault-password-old-source = my-domain-deployment-0da2c8296f744c90a236721486dbd258
vault-password-source = my-domain-deployment-042a98b666ec4e4e8e06de7d42688f3b

You can manage your key with the vault-key command. For easy exchange with other developers, you can also export and import the key via gpg using the vault-key export and vault-key import commands.

Per instance

groups

Whitespace separated list of Ansible group names this instance should be added to in addition to the default ones.

roles

Used by the configure command. This allows you to configure an instance by applying the whitespace separated roles. This is like creating a playbook which only specifies a host and a list of roles names. If the sudo option is set, it's also set for the generated playbook.

playbook

Allows you to explicitly specify a playbook to use for this instance. If you need sudo, then you have to add it yourself in that playbook.

Any option starting with ansible_ is passed through to Ansible as is. This can be used for settings like ansible_python_interpreter.

Any option starting with ansible- is stripped of the ansible- prefix and then passed through to Ansible. This is the main way to set Ansible variables for use in playbooks and roles.

All other options are prefixed with ploy_ and made available to Ansible.

Ansible inventory

All instances in ploy.conf are available to Ansible via their unique id.

The variables for each instance are gathered from group_vars, host_vars and the ploy.conf.

Ansible lookup plugins

The ploy_crypted lookup plugin can be used in playbooks to read the content of encrypted files. This is another way to access encrypted data where you don't have to move that data into yml files. An added benefit is, that the file is only decrypted when it is actually accessed. If you run tasks filtered by tags and those tasks don't access the encrypted data, then it's not decrypted at all.

Warning

This lookup plugin only works with files that are plain ascii or utf-8. It's a limitation caused by the way ansible handles variable substitution.

API usage

On the Python side, each ploy instance gains the following methods:

apply_playbook(self, playbook, *args, **kwargs)

Applies the playbook to the instance.

has_playbook

Return True if the instance has either of the roles or a playbook option set.

get_playbook(*args, **kwargs)

Returns an instance of the Ansible internal PlayBook class. This is either from a file (from playbook option or the playbook kwarg), or dynamically generated from the roles option.

configure(*args, **kwargs)

Configures the instance with the same semantics as the configure command.

get_ansible_variables

Returns the Ansible variables from the inventory. This does not include facts, as it doesn't connect to the instance. This is particularly useful in Fabric scripts.

get_vault_lib

Returns a readily usable Ansible VaultLib class. Use the encrypt and decrypt methods do encrypt/decrypt strings.

Known issues

On macOS when using a key stored in keyring, Ansible might hang with a message similar to the following: ` objc[81450]: +[__NSCFBoolean initialize] may have been in progress in another thread when fork() was called. objc[81450]: +[__NSCFBoolean initialize] may have been in progress in another thread when fork() was called. We cannot safely call it or ignore it in the fork() child process. Crashing instead. Set a breakpoint on objc_initializeAfterForkError to debug. ` This is caused by trying to access the secret from the keyring in a forked process.

To work around this you may have to add an encrypted host_vars yml for the affected host (or just one for the "all" group_vars) to trigger the key load early in Ansible.