This Ansible playbook contains a few tasks that are meant to extract short names from the system hostname and set certain facts (variables) based on those names and the environment. Here's a step-by-step explanation and documentation of what each task in the playbook does:

1. Shell Execution to Get Short Names:

   • The task is named "Get sit_short and hostname_short".
   • It uses the shell module to run two hostname commands, each piped into an awk` command.
   • The first command (hostname | awk -F '{print $1}') outputs the first part of the hostname, before the first dash ("-"), which will be considered as sitename_short.
   • The second command (hostname | awk -F- '{print $1$(-1)$NF}') combines the first part of the hostname with the penultimate and last parts. This composite is intended as a shorter version of the hostname, referred to as hostname_short.
   • The output of these shell commands is registered into a variable called shell_output.

2. Debug Output of Shell Commands:

   • The debug module is used to print the variable shell_output to the console This is useful for troubleshooting and confirming what the above shell commands produced.

3. Set Facts for sitename_short and hostname_short:

• This task sets two facts using the results from the shell_output variable.
  • sitename_short is set to the first line of the shell output (stdout_lines0]).
  • hostname_short is set to the second line of the shell output (stdout_lines[1]).
  • These facts can be used later in the playbook to reference the generated short names.

4. Overwrite hostname_short for Development Environment:
   • The task sets the hostname_short fact specifically when an environment variable env equals 'dev'.
   • It over the hostname_short with

Certainly! Let's go through the playbook step by step to understand what each part does:

1. Task: Get sitename_short and hostname_short

   • name: This is just a descriptive label for the task. It helps users understand the purpose of this particular task within the playbook.

   • shell: This Ansible module executes commands in a shell on the target host. Here, it's executing a series of commands connected through a pipe ("|") in a multi-line format, as indicated by the "|" character following shell: which allows for cleaner, more readable command definitions.

   • The hostname command retrieves the full hostname of the target system.

   • The awk command processes this hostname string. The -F- option specifies that the delimiter for fields is a hyphen ("-").

   • The first awk command, {print $1}, prints the first field of the hostname, meaning everything before the first hyphen. For example, if the hostname is web-server-01, this command would yield web.

   • The second awk command, {print $1$(NF-1)$NF}, prints a concatenation of the first field, the second to last field ($(NF-1), where NF stands for 'Number of Fields' in awk), and the last field ($NF). Continuing the previous example, it would yield webserv01.

   • register: shell_output: The output from running the shell command is saved in a variable named shell_output for use in subsequent tasks.

2. Task: Debug Output of Shell Commands

   • debug: This is a module used to print messages during playbook execution. Here, it's being used to print the contents of shell_output. This gives you insight into what was captured by the previous task and is mostly used for troubleshooting or verifying the output.

3. Set Facts for sitename_short and hostname_short

   • set_fact: This module is used to create or update variables during playbook execution.

   • Here, two facts are set: sitename_short and hostname_short.

   • sitename_short: "{{ shell_output.stdout_lines[0] }}": This takes the first line of output from shell_output, which resulted from the first awk command, and assigns it to sitename_short.

   • hostname_short: "{{ shell_output.stdout_lines[1] }}": This takes the second line of output from shell_output, which is the result of the second awk command, and assigns it to hostname_short.

   • These facts (sitename_short and hostname_short) now hold shorter versions of the system's hostname according to the rules defined by the awk commands.

4. Overwrite hostname_short if in dev environment

   • set_fact: This module is used again to set a specific fact.

   • hostname_short: "test": Here, it's setting the hostname_short to the hardcoded value "test".

   • when: env == 'dev': This line is a conditional. The fact is only set if the condition is true. The condition checks whether the variable env is equal to the string 'dev', implying that this playbook may take a different action depending on the environment it's being run against. If the environment is development (dev), then no matter what the previous tasks have set hostname_short to, it will be overridden with "test".

The playbook appears to be designed for configuration management with a focus on hostname handling, where it might be provisioning resources differently based on whether it's targeting a development environment or not. The final values of sitename_short and hostname_short are then likely used in subsequent tasks that are not shown in the snippet provided.