7. Exercise - Develop Your Own Resources

In this exercise, you will practice writing your own resources and consider how you could implement them in a profile.

Suggested Simple Resources to Start With:

• Docker

  • id: Retrieves the container ID.
  • image: Retrieves the image name.
  • repo: Retrieves the repository name.
  • tag: Retrieves the tag.
  • ports: Retrieves the ports.
  • command: Retrieves the command.

• Git

  • branches: Checks if a branch exists.
  • current_branch: Retrieves the current branch.
  • last_commit: Retrieves the last commit from the log.
  • git_log: Retrieves the log of all commits.
  • tag: Retrieves the tag for the repository.

Suggested Medium Complexity Resources to Start With:

• File Resource

  • owner: Tests if the owner of the file matches the specified value.
  • group: Tests if the group to which a file belongs matches the specified value.
  • size: Tests if a file’s size matches, is greater than, or is less than the specified value.
  • contents: Tests if contents in the file match the value specified in a regular expression.
  • path: Retrieves the path to the file.

• Directory Resource

  • owner: Tests if the owner of the directory matches the specified value.
  • group: Tests if the group to which a directory belongs matches the specified value.
  • size: Tests if a directory’s size matches, is greater than, or is less than the specified value.
  • contents: Tests if contents in the directory match the value specified in a regular expression.
  • path: Retrieves the path to the directory.

• Users

  • exist: Tests if the named user exists.
  • gid: Tests the group identifier.
  • group: Tests the group to which the user belongs.
  • groups: Tests if the user belongs to two (or more) groups.
  • home: Tests the home directory path for the user.
  • maxdays: Tests the maximum number of days between password changes.
  • mindays: Tests the minimum number of days between password changes.
  • shell: Tests the path to the default shell for the user.
  • uid: Tests the user identifier.
  • warndays: Tests the number of days a user is warned before a password must be changed.

• etc/hosts.allow and etc/hosts.deny

  • daemon: Returns a string containing the daemon that is allowed in the rule.
  • client_list: Returns a 2D string array where each entry contains the clients specified for the rule.
  • options: Returns a 2D string array where each entry contains any options specified for the rule.

Suggested Hard Resources to Start With:

• etc/shadow

  • users: A list of strings representing the usernames matched by the filter.
  • passwords: A list of strings representing the encrypted password strings for entries matched by the filter. Each string may not be an encrypted password but rather a * or similar, indicating that direct logins are not allowed.
  • last_changes: A list of integers indicating the number of days since Jan 1, 1970, since the password for each matching entry was changed.
  • min_days: A list of integers reflecting the minimum number of days a password must exist before it may be changed for the users that matched the filter.
  • max_days: A list of integers reflecting the maximum number of days after which the password must be changed for each user matching the filter.
  • warn_days: A list of integers reflecting the number of days a user is warned about an expiring password for each user matching the filter.
  • inactive_days: A list of integers reflecting the number of days a user must be inactive before the user account is disabled for each user matching the filter.
  • expiry_dates: A list of integers reflecting the number of days since Jan 1, 1970, that a user account has been disabled for each user matching the filter. The value is nil if the account has not expired.
  • count: Tests the number of records that the filter matched.

• etc/fstab

  • device_name: The name associated with the device.
  • mount_point: The directory at which the file system is configured to be mounted.
  • file_system_type: The type of file system of the device or partition.
  • mount_options: The options for the device or partition.
  • dump_options: A number used by dump to decide if a file system should be backed up.
  • file_system_options: A number that specifies the order the file system should be checked.

• Tomcat Server Configuration Reader

  • parse_conf: Parses the configuration file.
  • fetch_connectors: Retrieves keys such as port, protocol, timeout, redirect, sslprotocol, scheme, sslenable, clientauth, and secure.