Module utils 

Utility functions and helpers.

This module provides security-focused utilities with input validation and safe path handling to prevent common vulnerabilities.

Functions

file_exists

Checks if a file exists and is readable with path validation. Returns false for invalid or potentially dangerous paths.

get_base_directory

Extracts the base directory from a file path.

get_file_extension

Gets the file extension from a path.

has_path_traversal

Checks if a path contains potential traversal sequences.

is_image_file

Validates that a path points to an image file.

is_markdown_file

Validates that a path points to a markdown file.

is_safe_path

Validates that a path is safe to access (prevents path traversal and dangerous files).

resolve_path

Resolves relative paths against a base directory with security validation. Prevents path traversal attacks by validating the resolved path.

sanitize_filename

Sanitizes a filename by removing or replacing dangerous characters.

validate_app_credentials

Validates WeChat app credentials format.

validate_file_size

Validates file size limits to prevent DoS attacks.