Enhance CLI with Advanced Argument Parsing and Error Handling

[unclesp1d3r]

Summary

Enhance the existing CLI structure with comprehensive argument parsing, robust error handling, and additional command-line options to make StringyMcStringFace more flexible and user-friendly.

Background

The basic CLI structure has been established in src/main.rs using clap's derive API. Currently, it accepts a single input file argument. However, to make the tool production-ready, we need to expand the CLI with additional options and implement proper error handling for various failure scenarios.

Current State

• ✅ Basic clap integration with derive API (v4.5.48)
• ✅ Single file input argument
• ✅ Help text and version information
• ❌ No output file/format options
• ❌ Limited error handling for file operations
• ❌ No verbosity or logging controls
• ❌ No filtering or configuration options

Proposed Solution

1. Additional CLI Arguments

Add the following arguments to the Cli struct:

#[derive(Parser)]
#[command(name = "stringy")]
#[command(about = "Extract meaningful strings from binary files")]
#[command(version)]
struct Cli {
    /// Input binary file to analyze
    #[arg(value_name = "FILE")]
    input: PathBuf,
    
    /// Output file path (defaults to stdout)
    #[arg(short, long, value_name = "FILE")]
    output: Option<PathBuf>,
    
    /// Output format: json, text, csv
    #[arg(short = 'f', long, default_value = "text")]
    format: String,
    
    /// Minimum string length to extract
    #[arg(short = 'n', long, default_value = "4")]
    min_length: usize,
    
    /// Verbose output
    #[arg(short, long, action = clap::ArgAction::Count)]
    verbose: u8,
}

2. Error Handling

Implement comprehensive error handling for:

• File not found: Provide clear error message with file path
• Permission denied: Inform user about access issues
• Invalid file format: Detect and report unsupported file types
• Output write failures: Handle disk full, permission issues
• Invalid arguments: Validate min_length, format options, etc.

Create a custom error type using thiserror (already in dependencies):

#[derive(Debug, thiserror::Error)]
enum CliError {
    #[error("Failed to read input file '{0}': {1}")]
    InputFileError(PathBuf, std::io::Error),
    
    #[error("Failed to write output file '{0}': {1}")]
    OutputFileError(PathBuf, std::io::Error),
    
    #[error("Unsupported output format: {0}. Supported formats: json, text, csv")]
    UnsupportedFormat(String),
    
    #[error("Invalid minimum length: {0}. Must be between 1 and 1024")]
    InvalidMinLength(usize),
}

3. Input Validation

Add validation logic in main():

• Check if input file exists and is readable
• Validate output format against supported formats
• Validate min_length is within reasonable bounds (1-1024)
• Ensure output path is writable (if specified)

4. Verbosity Handling

Implement basic logging based on verbose flag:

• -v: Info level (show file being processed)
• -vv: Debug level (show detailed extraction info)
• -vvv: Trace level (show all internal operations)

Acceptance Criteria

• CLI accepts output file path with -o/--output flag
• CLI accepts output format with -f/--format flag (json, text, csv)
• CLI accepts minimum string length with -n/--min-length flag
• CLI accepts verbosity flag -v/-vv/-vvv
• Clear error messages for file not found
• Clear error messages for permission issues
• Clear error messages for invalid arguments
• Validation for output format (only json, text, csv allowed)
• Validation for min_length (1-1024)
• Help text is comprehensive and includes examples
• All error cases return appropriate exit codes

Testing Checklist

• Test with non-existent input file
• Test with unreadable input file (permissions)
• Test with invalid output format
• Test with invalid min_length (0, negative, too large)
• Test output to file vs stdout
• Test verbosity levels
• Test --help output
• Test --version output

Implementation Notes

• Use clap's built-in validation features where possible (value_parser)
• Consider using clap::ValueEnum for the format argument for type-safe parsing
• Keep error messages user-friendly and actionable
• Consider adding color to error output using a crate like colored

References

• clap documentation
• thiserror documentation

Task-ID

stringy-analyzer/basic-cli-structure

Requirements

7.7

[unclesp1d3r]

@coderabbitai Enhance this issue body with additional context and a proposed solution. Improve the issue title and assign the proper labels and other metadata.

[coderabbitai]

Tip

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#!/bin/bash
# Update the issue with enhanced content
gh issue edit 29 \
  --title "Enhance CLI with Advanced Argument Parsing and Error Handling" \
  --body "## Summary

Enhance the existing CLI structure with comprehensive argument parsing, robust error handling, and additional command-line options to make StringyMcStringFace more flexible and user-friendly.

## Background

The basic CLI structure has been established in \`src/main.rs\` using clap's derive API. Currently, it accepts a single input file argument. However, to make the tool production-ready, we need to expand the CLI with additional options and implement proper error handling for various failure scenarios.

## Current State

- ✅ Basic clap integration with derive API (v4.5.48)
- ✅ Single file input argument
- ✅ Help text and version information
- ❌ No output file/format options
- ❌ Limited error handling for file operations
- ❌ No verbosity or logging controls
- ❌ No filtering or configuration options

## Proposed Solution

### 1. Additional CLI Arguments

Add the following arguments to the \`Cli\` struct:

\`\`\`rust
#[derive(Parser)]
#[command(name = \"stringy\")]
#[command(about = \"Extract meaningful strings from binary files\")]
#[command(version)]
struct Cli {
    /// Input binary file to analyze
    #[arg(value_name = \"FILE\")]
    input: PathBuf,
    
    /// Output file path (defaults to stdout)
    #[arg(short, long, value_name = \"FILE\")]
    output: Option<PathBuf>,
    
    /// Output format: json, text, csv
    #[arg(short = 'f', long, default_value = \"text\")]
    format: String,
    
    /// Minimum string length to extract
    #[arg(short = 'n', long, default_value = \"4\")]
    min_length: usize,
    
    /// Verbose output
    #[arg(short, long, action = clap::ArgAction::Count)]
    verbose: u8,
}
\`\`\`

### 2. Error Handling

Implement comprehensive error handling for:
- **File not found**: Provide clear error message with file path
- **Permission denied**: Inform user about access issues
- **Invalid file format**: Detect and report unsupported file types
- **Output write failures**: Handle disk full, permission issues
- **Invalid arguments**: Validate min_length, format options, etc.

Create a custom error type using \`thiserror\` (already in dependencies):

\`\`\`rust
#[derive(Debug, thiserror::Error)]
enum CliError {
    #[error(\"Failed to read input file '{0}': {1}\")]
    InputFileError(PathBuf, std::io::Error),
    
    #[error(\"Failed to write output file '{0}': {1}\")]
    OutputFileError(PathBuf, std::io::Error),
    
    #[error(\"Unsupported output format: {0}. Supported formats: json, text, csv\")]
    UnsupportedFormat(String),
    
    #[error(\"Invalid minimum length: {0}. Must be between 1 and 1024\")]
    InvalidMinLength(usize),
}
\`\`\`

### 3. Input Validation

Add validation logic in \`main()\`:
- Check if input file exists and is readable
- Validate output format against supported formats
- Validate min_length is within reasonable bounds (1-1024)
- Ensure output path is writable (if specified)

### 4. Verbosity Handling

Implement basic logging based on verbose flag:
- \`-v\`: Info level (show file being processed)
- \`-vv\`: Debug level (show detailed extraction info)
- \`-vvv\`: Trace level (show all internal operations)

## Acceptance Criteria

- [ ] CLI accepts output file path with \`-o/--output\` flag
- [ ] CLI accepts output format with \`-f/--format\` flag (json, text, csv)
- [ ] CLI accepts minimum string length with \`-n/--min-length\` flag
- [ ] CLI accepts verbosity flag \`-v/-vv/-vvv\`
- [ ] Clear error messages for file not found
- [ ] Clear error messages for permission issues
- [ ] Clear error messages for invalid arguments
- [ ] Validation for output format (only json, text, csv allowed)
- [ ] Validation for min_length (1-1024)
- [ ] Help text is comprehensive and includes examples
- [ ] All error cases return appropriate exit codes

## Testing Checklist

- [ ] Test with non-existent input file
- [ ] Test with unreadable input file (permissions)
- [ ] Test with invalid output format
- [ ] Test with invalid min_length (0, negative, too large)
- [ ] Test output to file vs stdout
- [ ] Test verbosity levels
- [ ] Test \`--help\` output
- [ ] Test \`--version\` output

## Implementation Notes

- Use clap's built-in validation features where possible (value_parser)
- Consider using \`clap::ValueEnum\` for the format argument for type-safe parsing
- Keep error messages user-friendly and actionable
- Consider adding color to error output using a crate like \`colored\`

## References

- [clap documentation](https://docs.rs/clap/latest/clap/)
- [thiserror documentation](https://docs.rs/thiserror/latest/thiserror/)

## Task-ID
stringy-analyzer/basic-cli-structure

## Requirements
7.7" \
  --add-label "good first issue"

echo "Issue updated successfully!"

Length of output: 90

---

@unclesp1d3r I've successfully enhanced issue #29 with comprehensive improvements:

What Changed:

📝 Title

• Before: "Basic CLI Structure"
• After: "Enhance CLI with Advanced Argument Parsing and Error Handling"

📄 Body Enhancements

1. Background Context: Explained that basic CLI already exists and needs enhancement
2. Current State: Added checklist showing what's implemented vs what's missing
3. Proposed Solution: Detailed implementation plan with code examples for:
   • Additional CLI arguments (output file, format, min-length, verbosity)
   • Custom error types using thiserror
   • Input validation strategies
   • Verbosity level handling
4. Acceptance Criteria: 11 specific checkboxes for feature completion
5. Testing Checklist: 8 test scenarios to validate implementation
6. Implementation Notes: Best practices and recommendations
7. References: Links to relevant documentation

🏷️ Labels

• Added: good first issue (well-scoped with clear implementation guidance)
• Retained: area:analyzer, type:enhancement, status:backlog, lang:rust, needs:tests

The issue now provides a complete roadmap for implementing advanced CLI features with proper error handling, making it easy for contributors to understand what needs to be done and how to approach it.