try-except写得太粗什么异常都catch了——异常处理最佳实践

常见反模式和正确写法

# 反模式：except pass
try: data = process(row)
except Exception: pass  # 数据丢了不知道！
 
# 正确：catch具体异常+记录+计数
for row in rows:
    try: data = process(row)
    except (ValueError, KeyError) as e:
        error_count += 1
        logging.warning(f'Skip: {e}')
if error_count > len(rows) * 0.01:
    raise RuntimeError(f'Too many errors: {error_count}')

ETL异常策略

# 完整ETL异常模板
def run_etl():
    error_rows = []; total = 0
    try:
        conn = get_connection()  # 配置错直接崩
        df = load_data(conn)
        for idx, row in df.iterrows():
            total += 1
            try:
                save(transform(row))
            except (ValueError, KeyError) as e:
                error_rows.append((idx, str(e)))
        if len(error_rows)/max(total,1) > 0.01:
            send_alert(f'{len(error_rows)} errors in {total} rows')
    except Exception as e:
        logging.error(f'ETL failed: {e}', exc_info=True)
        raise  # 让调度系统知道失败