How to use Ansible Stat module to get file size?

Using Ansible Stat Module to Get File Size

The Ansible stat module is a powerful tool that allows you to retrieve information about a file or directory on the remote host. One of the key pieces of information you can retrieve using the stat module is the file size.

Understanding the Ansible Stat Module

The stat module in Ansible is used to retrieve information about a file or directory on the remote host. It can provide a wide range of information, including:

• File type (regular file, directory, symlink, etc.)
• File permissions
• File owner and group
• File size
• File modification and access times
• And more

To use the stat module, you need to specify the path to the file or directory you want to inspect. The module will then return a dictionary of information about the specified file or directory.

Retrieving File Size with the Stat Module

To retrieve the file size using the stat module, you can use the following Ansible task:

- name: Get file size
  stat:
    path: /path/to/file.txt
  register: file_stats

In this example, the stat module is used to retrieve information about the file located at /path/to/file.txt. The retrieved information is stored in the file_stats variable, which can then be used in subsequent tasks.

To access the file size, you can use the file_stats.stat.size variable, which will contain the size of the file in bytes. For example:

- name: Print file size
  debug:
    msg: "The file size is {{ file_stats.stat.size }} bytes."

This will output the file size in bytes.

Handling Errors and Edge Cases

It's important to note that the stat module can fail if the specified file or directory does not exist or if the user running the Ansible playbook does not have the necessary permissions to access the file or directory. To handle these cases, you can use the failed_when and changed_when options in your Ansible tasks.

For example:

- name: Get file size
  stat:
    path: /path/to/file.txt
  register: file_stats
  failed_when: file_stats.stat.exists == false
  changed_when: false

In this example, the failed_when option ensures that the task will fail if the file does not exist, and the changed_when option ensures that the task will never report a change, even if the file size has changed.

Conclusion

The Ansible stat module is a versatile tool for retrieving information about files and directories on remote hosts. By using the stat module, you can easily retrieve the size of a file as part of your Ansible playbooks, allowing you to automate tasks that require knowledge of file sizes.