show_env.sh

Overview

show_env.sh is a Bash script designed to gather and display key environment and system information relevant for development and debugging purposes. It collects details such as the current Git repository name and commit ID, operating system distribution and version, CPU type, memory size, Docker version, and Python version. This script helps users quickly assess their runtime environment, particularly useful in software development, deployment, or troubleshooting contexts.

Detailed Explanation

Functions

`get_distro_info()`

Purpose:
Retrieves the Linux distribution ID and version along with the current kernel version.
Implementation details:
- Attempts to use lsb_release to get distribution info (ID and VERSION).
- If lsb_release is unavailable or returns empty, falls back to parsing /etc/*-release files for ID and VERSION_ID.
- Obtains the kernel version using uname -r.
- Returns a string combining the distribution ID, version, and kernel version.
Parameters:
None

Returns:
Outputs a single string in the format:

<distro_id> <distro_version> (Kernel version: <kernel_version>)

Usage example:

os_info=$(get_distro_info)
echo "Operating system: $os_info"

Script Variables and Commands

Variable/Command	Purpose	Details
`git_repo_name`	Name of the current Git repository	Uses `git rev-parse` to check if inside a Git repo and retrieve the repo top-level directory name. If not a Git repo or on error, sets appropriate message.
`cpu_model`	CPU architecture/type	Obtained via `uname -m` (e.g., x86_64, armv7l)
`memory_size`	Total system memory	Extracted from the output of `free -h` command, specifically the "Mem" line's total value (human-readable)
`docker_version`	Installed Docker version	Checks if `docker` command exists; if yes, extracts the version string; otherwise notes Docker is not installed
`python_version`	Installed Python version	Attempts to get Python 3 version, falls back to `python` version, or notes if Python is not installed
`git_version`	Commit ID of the latest Git commit	Uses `git log -1` to get the abbreviated commit hash; if unavailable, shows a message

Output

The script prints all gathered information to standard output in the following order:

Current Git repository name (or message if not in a Git repo)
Current Git commit ID (or message if not available)
Operating system distribution, version, and kernel version
CPU type
Memory size
Docker version
Python version

This output provides a snapshot of the development environment.

Important Implementation Details

Robustness with fallback mechanisms:
The script uses multiple methods to obtain system info, e.g., it tries lsb_release first, then falls back to parsing /etc/*-release files to maximize compatibility across Linux distros.
Error handling:
Where commands might fail (e.g., not a Git repo, missing Docker), the script sets clear, user-friendly messages rather than failing silently or crashing.
Command checks:
Uses command -v to check command availability (docker), and redirect error output to /dev/null to avoid clutter.
Use of standard Unix utilities:
Relies on standard commands like grep, cut, awk, uname, free, and git to extract information efficiently.

Interaction with Other System Components

Git:
The script interacts with Git repositories by querying the repository name and latest commit hash. It requires that the current directory be part of a Git repo and that Git is installed.
Docker:
Detects installed Docker version if Docker is available in the system PATH.
Operating System:
Uses OS-level commands and files to get distribution and kernel information.
Python:
Queries the installed Python interpreter version, trying python3 first, then python.

This script is typically run from a shell environment within a development machine or container and does not modify system state.

Usage Example

./show_env.sh

Sample output might be:

Current Repository: my-project
Commit Id: a1b2c3d
Operating system: Ubuntu 22.04 (Kernel version: 5.15.0-50-generic)
CPU Type: x86_64
Memory: 15Gi
Docker Version: 20.10.7
Python Version: Python 3.10.4

Mermaid Diagram: Flowchart of Main Steps and Data Flow

flowchart TD
    Start((Start))
    A[get_distro_info()]
    B[Check if inside Git repo]
    C[Get Git repo name]
    D[Get latest commit ID]
    E[Get CPU type]
    F[Get Memory size]
    G[Check Docker installation & version]
    H[Check Python installation & version]
    I[Print all collected info]
    End((End))

    Start --> A
    A --> B
    B -->|Yes| C
    B -->|No| C
    C --> D
    D --> E
    E --> F
    F --> G
    G --> H
    H --> I
    I --> End

Summary

show_env.sh is a utility script that provides a concise environmental snapshot by combining system, Git, Docker, and Python details. It is useful for developers to verify their current environment quickly and can be integrated into larger scripts or CI/CD pipelines for environment validation.

Notes

Requires Git for full functionality.
For optimal results, run in a Linux environment.
Python and Docker versions are only reported if those tools are installed and accessible in the shell environment.