Torrust Dependency Installer Package

This package provides dependency detection and installation utilities for the Torrust Tracker Deployer project.

Design Philosophy

This is an internal automation tool - Its primary purpose is to check dependencies in CI/CD pipelines and automated workflows. As such, it uses structured logging only (via the tracing crate) rather than user-facing console output.

This design choice offers several benefits:

• Automation-friendly: Structured logs are easy to parse and filter programmatically
• Consistent: Same output format as the rest of the Torrust ecosystem
• Simple: The tool is straightforward enough that logging output is sufficient even for manual use
• Observable: Rich contextual information through structured fields

For manual usage, you can control log verbosity with the --verbose flag or RUST_LOG environment variable.

Features

• Dependency Detection: Check if required development tools are installed
• Extensible: Easy to add new dependency detectors
• Structured Logging: Built-in tracing support for observability and automation
• Type-Safe: Uses strongly-typed enums for dependencies
• Error Handling: Clear, actionable error messages

Supported Dependencies

This package can detect the following development dependencies:

• cargo-machete - Detects unused Rust dependencies
• OpenTofu - Infrastructure provisioning tool
• Ansible - Configuration management tool
• LXD - VM-based testing infrastructure

Usage

CLI Binary

The package provides a dependency-installer binary for command-line usage:

# Check all dependencies (default: info log level)
dependency-installer check

# Check specific dependency
dependency-installer check --dependency opentofu

# List all dependencies with status
dependency-installer list

# Control log level (off, error, warn, info, debug, trace)
dependency-installer check --log-level debug
dependency-installer check --log-level off   # Disable all logging

# Enable verbose logging (equivalent to --log-level debug)
dependency-installer check --verbose

# Get help
dependency-installer --help
dependency-installer check --help

Exit Codes

• 0: Success (all checks passed)
• 1: Missing dependencies
• 2: Invalid arguments
• 3: Internal error

Output Format

The tool uses structured logging (via tracing) instead of plain text output:

# Check all dependencies (default log level shows INFO and above)
$ dependency-installer check
2025-11-04T17:33:20.959847Z  INFO torrust_dependency_installer::handlers::check: Checking all dependencies
2025-11-04T17:33:20.960126Z  INFO torrust_dependency_installer::handlers::check: Dependency check result dependency="cargo-machete" status="installed"
2025-11-04T17:33:20.960131Z  INFO torrust_dependency_installer::handlers::check: Dependency check result dependency="OpenTofu" status="not installed"
2025-11-04T17:33:20.960136Z  INFO torrust_dependency_installer::handlers::check: Dependency check result dependency="Ansible" status="not installed"
2025-11-04T17:33:20.960139Z  INFO torrust_dependency_installer::handlers::check: Dependency check result dependency="LXD" status="installed"
2025-11-04T17:33:20.960144Z  INFO torrust_dependency_installer::handlers::check: Missing dependencies missing_count=2 total_count=4
Error: Check command failed: Failed to check all dependencies: Missing 2 out of 4 required dependencies

# Check specific dependency
$ dependency-installer check --dependency opentofu
2025-11-04T17:33:20.959855Z  INFO torrust_dependency_installer::handlers::check: Checking specific dependency dependency=opentofu
2025-11-04T17:33:20.960473Z  INFO torrust_dependency_installer::detector::opentofu: OpenTofu is not installed dependency="opentofu"
2025-11-04T17:33:20.960482Z  INFO torrust_dependency_installer::handlers::check: Dependency is not installed dependency="OpenTofu" status="not installed"
Error: Check command failed: Failed to check specific dependency: opentofu: not installed

# List all dependencies
$ dependency-installer list
2025-11-04T17:33:20.960482Z  INFO torrust_dependency_installer::handlers::list: Available dependency dependency="cargo-machete" status="installed"
2025-11-04T17:33:20.960494Z  INFO torrust_dependency_installer::handlers::list: Available dependency dependency="OpenTofu" status="not installed"
2025-11-04T17:33:20.960962Z  INFO torrust_dependency_installer::handlers::list: Available dependency dependency="Ansible" status="not installed"
2025-11-04T17:33:20.961521Z  INFO torrust_dependency_installer::handlers::list: Available dependency dependency="LXD" status="installed"

# Enable verbose logging (includes DEBUG level)
$ dependency-installer check --verbose
2025-11-04T17:33:20.959872Z DEBUG torrust_dependency_installer::detector::cargo_machete: Checking if cargo-machete is installed dependency="cargo-machete"
...

Dependency Names

The CLI accepts the following dependency names:

• cargo-machete - Rust dependency analyzer
• opentofu - Infrastructure provisioning tool
• ansible - Configuration management tool
• lxd - Lightweight VM manager

Library Usage

Checking Dependencies

use torrust_dependency_installer::DependencyManager;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Initialize tracing for structured logging
    tracing_subscriber::fmt::init();

    let manager = DependencyManager::new();

    // Check all dependencies
    let results = manager.check_all()?;

    for result in results {
        let detector = manager.get_detector(result.dependency);
        tracing::info!(
            dependency = detector.name(),
            installed = result.installed,
            "Dependency status"
        );
    }

    Ok(())
}

Using Individual Detectors

use torrust_dependency_installer::{DependencyDetector, Dependency, DependencyManager};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    tracing_subscriber::fmt::init();

    let manager = DependencyManager::new();
    let detector = manager.get_detector(Dependency::OpenTofu);

    if detector.is_installed()? {
        tracing::info!(dependency = detector.name(), "Dependency is installed");
    } else {
        tracing::warn!(dependency = detector.name(), "Dependency is not installed");
    }

    Ok(())
}

Adding to Your Project

Add to your Cargo.toml:

[dependencies]
torrust-dependency-installer = { path = "path/to/torrust-dependency-installer" }

Or if using in a workspace:

[workspace]
members = ["packages/torrust-dependency-installer"]

[dependencies]
torrust-dependency-installer = { path = "packages/torrust-dependency-installer" }