validation.py•4.58 kB
"""
参数验证工具
提供各种参数验证功能
"""
import re
import os
import base64
from typing import Union, Tuple, Any
def validate_image_source(source: str) -> bool:
"""
验证图片源是否有效
Args:
source: 图片源（文件路径或base64编码）
Returns:
bool: 是否有效
"""
if not source or not isinstance(source, str):
return False
# 检查是否为文件路径
if not source.startswith('data:image'):
return os.path.exists(source) and os.path.isfile(source)
# 检查是否为有效的base64格式
try:
if ',' in source:
header, data = source.split(',', 1)
if not header.startswith('data:image'):
return False
base64.b64decode(data)
return True
except Exception:
return False
return False
def validate_numeric_range(value: Union[int, float], min_val: Union[int, float],
max_val: Union[int, float], param_name: str = None) -> bool:
"""
验证数值是否在指定范围内
Args:
value: 要验证的值
min_val: 最小值
max_val: 最大值
param_name: 参数名称（用于错误消息）
Returns:
bool: 是否在范围内
"""
try:
num_value = float(value)
return min_val <= num_value <= max_val
except (ValueError, TypeError):
return False
def validate_color_hex(color: str) -> bool:
"""
验证十六进制颜色格式
Args:
color: 颜色字符串
Returns:
bool: 是否为有效的十六进制颜色
"""
if not isinstance(color, str):
return False
# 支持 #RGB, #RRGGBB, #RRGGBBAA 格式
pattern = r'^#([A-Fa-f0-9]{3}|[A-Fa-f0-9]{6}|[A-Fa-f0-9]{8})$'
return bool(re.match(pattern, color))
def validate_image_dimensions(width: int, height: int, max_size: Tuple[int, int] = (4096, 4096)) -> bool:
"""
验证图片尺寸是否合理
Args:
width: 宽度
height: 高度
max_size: 最大尺寸限制
Returns:
bool: 是否合理
"""
try:
w, h = int(width), int(height)
return 1 <= w <= max_size[0] and 1 <= h <= max_size[1]
except (ValueError, TypeError):
return False
def validate_crop_coordinates(left: int, top: int, right: int, bottom: int,
image_width: int, image_height: int) -> bool:
"""
验证裁剪坐标是否有效
Args:
left, top, right, bottom: 裁剪坐标
image_width, image_height: 图片尺寸
Returns:
bool: 坐标是否有效
"""
try:
l, t, r, b = int(left), int(top), int(right), int(bottom)
return (0 <= l < r <= image_width and
0 <= t < b <= image_height)
except (ValueError, TypeError):
return False
def validate_resample_method(method: str) -> bool:
"""
验证重采样方法是否支持
Args:
method: 重采样方法名称
Returns:
bool: 是否支持
"""
valid_methods = ['NEAREST', 'BILINEAR', 'BICUBIC', 'LANCZOS']
return method.upper() in valid_methods
def validate_image_format(format_name: str) -> bool:
"""
验证图片格式是否支持
Args:
format_name: 格式名称
Returns:
bool: 是否支持
"""
valid_formats = ['JPEG', 'PNG', 'BMP', 'TIFF', 'WEBP']
return format_name.upper() in valid_formats
class ValidationError(Exception):
"""参数验证错误"""
pass
def ensure_valid_image_source(source: str) -> str:
"""
确保图片源有效，无效时抛出异常
Args:
source: 图片源
Returns:
str: 验证后的图片源
Raises:
ValidationError: 当图片源无效时
"""
if not validate_image_source(source):
raise ValidationError(f"无效的图片源: {source}")
return source
def ensure_valid_dimensions(width: int, height: int) -> Tuple[int, int]:
"""
确保图片尺寸有效，无效时抛出异常
Args:
width, height: 图片尺寸
Returns:
Tuple[int, int]: 验证后的尺寸
Raises:
ValidationError: 当尺寸无效时
"""
if not validate_image_dimensions(width, height):
raise ValidationError(f"无效的图片尺寸: {width}x{height}")
return int(width), int(height)