如何从protobuf文本中提取text字段值 支持可选pinned_field匹配

将protobuf转换为字符串做文本提取的思路是可行的，你现有代码的核心问题是错误调用了re.escape()转义了正则的特殊语法，导致匹配规则完全失效，调整正则规则和匹配逻辑即可实现需求。

基础需求实现（仅提取text内容） #

预期输出：["5 Best Products","10 Best Products 2021"]
代码如下：

import re

def extract_text_from_proto(proto_string):
    # 正则匹配text字段双引号内的内容
    regex = r'text:\s*"([^"]+)"'
    result = [m.group(1) for m in re.finditer(regex, proto_string)]
    return result

# 测试调用
proto_content = '''[pinned_field: HEADLINE_1
text: "5 Best Products"
asset_performance_label: PENDING
policy_summary_info
{
    review_status: REVIEWED
    approval_status: APPROVED
}
, pinned_field: HEADLINE_1
text: "10 Best Products 2021"
asset_performance_label: PENDING
policy_summary_info
{
    review_status: REVIEWED
    approval_status: APPROVED
}
# 测试无pinned_field的场景
text: "some_text_without_pinned_field"
asset_performance_label: PENDING
'''

print(extract_text_from_proto(proto_content))
# 输出：['5 Best Products', '10 Best Products 2021', 'some_text_without_pinned_field']

进阶需求实现（可选匹配pinned_field） #

预期输出：['HEADLINE_1: 5 Best Products', 'HEADLINE_1: 10 Best Products 2021', 'some_text_without_pinned_field']
代码如下：

import re

def extract_text_with_pinned(proto_string):
    # 正则中(?:...)?表示可选的非捕获组，优先捕获pinned_field的值，再捕获text内容
    regex = r'(?:pinned_field:\s*(\w+)\s+)?text:\s*"([^"]+)"'
    result = []
    for m in re.finditer(regex, proto_string):
        pinned = m.group(1)
        text = m.group(2)
        if pinned:
            result.append(f"{pinned}: {text}")
        else:
            result.append(text)
    return result

# 测试调用
print(extract_text_with_pinned(proto_content))
# 输出：['HEADLINE_1: 5 Best Products', 'HEADLINE_1: 10 Best Products 2021', 'some_text_without_pinned_field']

正则规则说明 #

• (?:pinned_field:\s*(\w+)\s+)?：可选匹配pinned_field: 字段值结构，(\w+)捕获字段值，整个片段不存在时也不影响后续text的匹配
• text:\s*"([^"]+)"：匹配text字段，([^"]+)捕获双引号内的所有内容，自动截断到双引号结束位置，不需要额外匹配asset_performance_label做边界

内容的提问来源于stack exchange，提问作者Elad Benda