python3中twisted出现NameError: name ‘file’ is not def

本文针对使用Python3遇到的Twisted模块兼容性问题进行了解析,并提供了一个有效的解决方案,即通过修改文件中_open变量的定义,使得Twisted能够正常运行。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

问题:File "D:\Python33\lib\site-packages\twisted\python\lockfile.py", line 52, in <
module>
_open = file
NameError: name ‘file’ is not defined
原因:这个问题是因为twisted不支持Python3的原因,Python3没有file内建方法用open来代替
python2x(file(filename[, mode[, bufsize]]) When opening a file, it’s preferable to use open() instead of

invoking this constructor directly. file is more suited to type testing (for example, writing isinstance(f,

file)).)

解决这个问题: 将 _open = file 改为:

try:
     _open = file
except:
     _open = open


参考:http://mojijs.com/2014/04/134219/index.html

转载于:https://my.oschina.net/soarwilldo/blog/393420

PS D:\conda_Test\baidu_spider\baidu_spider> scrapy crawl baidu -o realtime.csv 2025-06-26 20:37:39 [scrapy.utils.log] INFO: Scrapy 2.11.1 started (bot: baidu_spider) 2025-06-26 20:37:39 [scrapy.utils.log] INFO: Versions: lxml 5.2.1.0, libxml2 2.13.1, cssselect 1.2.0, parsel 1.8.1, w3lib 2.1.2, Twisted 23.10.0, Python 3.12.7 | packaged by Anaconda, Inc. | (main, Oct 4 2024, 13:17:27) [MSC v.1929 64 bit (AMD64)], pyOpenSSL 24.2.1 (OpenSSL 3.0.16 11 Feb 2025), cryptography 43.0.0, Platform Windows-11-10.0.22631-SP0 2025-06-26 20:37:39 [scrapy.addons] INFO: Enabled addons: [] 2025-06-26 20:37:39 [asyncio] DEBUG: Using selector: SelectSelector 2025-06-26 20:37:39 [scrapy.utils.log] DEBUG: Using reactor: twisted.internet.asyncioreactor.AsyncioSelectorReactor 2025-06-26 20:37:39 [scrapy.utils.log] DEBUG: Using asyncio event loop: asyncio.windows_events._WindowsSelectorEventLoop 2025-06-26 20:37:39 [scrapy.extensions.telnet] INFO: Telnet Password: 40e94de686f0a93d 2025-06-26 20:37:39 [scrapy.middleware] INFO: Enabled extensions: [&#39;scrapy.extensions.corestats.CoreStats&#39;, &#39;scrapy.extensions.telnet.TelnetConsole&#39;, &#39;scrapy.extensions.feedexport.FeedExporter&#39;, &#39;scrapy.extensions.logstats.LogStats&#39;] 2025-06-26 20:37:39 [scrapy.crawler] INFO: Overridden settings: {&#39;BOT_NAME&#39;: &#39;baidu_spider&#39;, &#39;FEED_EXPORT_ENCODING&#39;: &#39;utf-8&#39;, &#39;NEWSPIDER_MODULE&#39;: &#39;baidu_spider.spiders&#39;, &#39;REQUEST_FINGERPRINTER_IMPLEMENTATION&#39;: &#39;2.7&#39;, &#39;ROBOTSTXT_OBEY&#39;: True, &#39;SPIDER_MODULES&#39;: [&#39;baidu_spider.spiders&#39;], &#39;TWISTED_REACTOR&#39;: &#39;twisted.internet.asyncioreactor.AsyncioSelectorReactor&#39;} 2025-06-26 20:37:40 [scrapy.middleware] INFO: Enabled downloader middlewares: [&#39;scrapy.downloadermiddlewares.robotstxt.RobotsTxtMiddleware&#39;, &#39;scrapy.downloadermiddlewares.httpauth.HttpAuthMiddleware&#39;, &#39;scrapy.downloadermiddlewares.downloadtimeout.DownloadTimeoutMiddleware&#39;, &#39;scrapy.downloadermiddlewares.defaultheaders.DefaultHeadersMiddleware&#39;, &#39;scrapy.downloadermiddlewares.useragent.UserAgentMiddleware&#39;, &#39;scrapy.downloadermiddlewares.retry.RetryMiddleware&#39;, &#39;scrapy.downloadermiddlewares.redirect.MetaRefreshMiddleware&#39;, &#39;scrapy.downloadermiddlewares.httpcompression.HttpCompressionMiddleware&#39;, &#39;scrapy.downloadermiddlewares.redirect.RedirectMiddleware&#39;, &#39;scrapy.downloadermiddlewares.cookies.CookiesMiddleware&#39;, &#39;scrapy.downloadermiddlewares.httpproxy.HttpProxyMiddleware&#39;, &#39;scrapy.downloadermiddlewares.stats.DownloaderStats&#39;] 2025-06-26 20:37:40 [scrapy.middleware] INFO: Enabled spider middlewares: [&#39;scrapy.spidermiddlewares.httperror.HttpErrorMiddleware&#39;, &#39;scrapy.spidermiddlewares.offsite.OffsiteMiddleware&#39;, &#39;scrapy.spidermiddlewares.referer.RefererMiddleware&#39;, &#39;scrapy.spidermiddlewares.urllength.UrlLengthMiddleware&#39;, &#39;scrapy.spidermiddlewares.depth.DepthMiddleware&#39;] 2025-06-26 20:37:40 [scrapy.middleware] INFO: Enabled item pipelines: [&#39;baidu_spider.pipelines.BaiduSpiderPrintPipeline&#39;, &#39;baidu_spider.pipelines.BaiduSpiderPipeline&#39;] 2025-06-26 20:37:40 [scrapy.core.engine] INFO: Spider opened 2025-06-26 20:37:40 [scrapy.core.engine] INFO: Closing spider (shutdown) 2025-06-26 20:37:40 [baidu] INFO: 执行了close_spider方法,项目已经关闭 2025-06-26 20:37:40 [scrapy.utils.signal] ERROR: Error caught on signal handler: <bound method CoreStats.spider_closed of <scrapy.extensions.corestats.CoreStats object at 0x000001BB483C0470>> Traceback (most recent call last): File "D:\anaconda3\Lib\site-packages\scrapy\crawler.py", line 160, in crawl yield self.engine.open_spider(self.spider, start_requests) NameError: name &#39;baidu_spider&#39; is not defined During handling of the above exception, another exception occurred: Traceback (most recent call last): File "D:\anaconda3\Lib\site-packages\scrapy\utils\defer.py", line 348, in maybeDeferred_coro result = f(*args, **kw) File "D:\anaconda3\Lib\site-packages\pydispatch\robustapply.py", line 55, in robustApply return receiver(*arguments, **named) File "D:\anaconda3\Lib\site-packages\scrapy\extensions\corestats.py", line 30, in spider_closed elapsed_time = finish_time - self.start_time TypeError: unsupported operand type(s) for -: &#39;datetime.datetime&#39; and &#39;NoneType&#39; 2025-06-26 20:37:40 [scrapy.statscollectors] INFO: Dumping Scrapy stats: {&#39;log_count/DEBUG&#39;: 3, &#39;log_count/ERROR&#39;: 1, &#39;log_count/INFO&#39;: 9} 2025-06-26 20:37:40 [scrapy.core.engine] INFO: Spider closed (shutdown) Unhandled error in Deferred: 2025-06-26 20:37:40 [twisted] CRITICAL: Unhandled error in Deferred: Traceback (most recent call last): File "D:\anaconda3\Lib\site-packages\twisted\internet\defer.py", line 874, in callback self._startRunCallbacks(result) File "D:\anaconda3\Lib\site-packages\twisted\internet\defer.py", line 981, in _startRunCallbacks self._runCallbacks() File "D:\anaconda3\Lib\site-packages\twisted\internet\defer.py", line 1075, in _runCallbacks current.result = callback( # type: ignore[misc] File "D:\anaconda3\Lib\site-packages\twisted\internet\defer.py", line 1946, in _gotResultInlineCallbacks _inlineCallbacks(r, gen, status, context) --- <exception caught here> --- File "D:\anaconda3\Lib\site-packages\twisted\internet\defer.py", line 2000, in _inlineCallbacks result = context.run(gen.send, result) File "D:\anaconda3\Lib\site-packages\scrapy\crawler.py", line 160, in crawl yield self.engine.open_spider(self.spider, start_requests) builtins.NameError: name &#39;baidu_spider&#39; is not defined 2025-06-26 20:37:40 [twisted] CRITICAL: Traceback (most recent call last): File "D:\anaconda3\Lib\site-packages\twisted\internet\defer.py", line 2000, in _inlineCallbacks result = context.run(gen.send, result) File "D:\anaconda3\Lib\site-packages\scrapy\crawler.py", line 160, in crawl yield self.engine.open_spider(self.spider, start_requests) NameError: name &#39;baidu_spider&#39; is not defined PS D:\conda_Test\baidu_spider\baidu_spider> 如何解决
06-27
<think>我们正在处理用户关于Scrapy爬虫启动时出现的两个错误:1.NameError:name&#39;baidu_spider&#39;isnotdefined2.TypeError:unsupportedoperandtype(s)for-:&#39;datetime.datetime&#39;and&#39;NoneType&#39;首先,我们需要分析这两个错误的原因。错误1:NameError:name&#39;baidu_spider&#39;isnotdefined这个错误通常是由于尝试使用一个未定义的变量或类名引起的。在Scrapy中,爬虫类需要在spiders目录下的文件中定义,并且在运行爬虫时,Scrapy会通过名称来查找爬虫类。可能的原因包括:-爬虫类没有正确命名(例如,类名应该是`BaiduSpider`,但实际可能是其他名字)-爬虫文件没有放在正确的目录(scrapy项目结构要求爬虫文件在`spiders`目录下)-在代码中引用了`baidu_spider`这个变量,但该变量并没有被定义错误2:TypeError:unsupportedoperandtype(s)for-:&#39;datetime.datetime&#39;and&#39;NoneType&#39;这个错误发生在尝试对`datetime.datetime`对象和`None`进行减法操作时。在Scrapy中,这通常与请求或响应的处理有关,尤其是在设置`meta`数据传递时。可能的原因包括:-在回调函数中,尝试计算时间差,但其中一个时间是`None`(例如,在`meta`中传递的起始时间没有正确设置)-在中间件或扩展中,处理时间时某个时间值为`None`解决步骤:1.解决NameError:-确认爬虫类是否已经定义。在`spiders`目录下的某个文件中,应该有一个名为`BaiduSpider`的类(注意大小写,Python是大小写敏感的)。-检查运行爬虫的命令是否正确。例如,运行爬虫的命令应该是:`scrapycrawlbaidu`(这里的`baidu`是爬虫的`name`属性,定义在爬虫类中)。-如果是在代码中(如`run.py`)使用`CrawlerProcess`启动爬虫,确保正确导入了爬虫类。例如:```pythonfrommyproject.spiders.baidu_spiderimportBaiduSpider```-注意:Scrapy要求爬虫类必须在`spiders`包中,并且类名通常采用驼峰命名法,而爬虫名称(name)通常是小写。2.解决TypeError:-检查代码中所有涉及时间减法的操作,尤其是使用`datetime.datetime.now()`和从`meta`中获取时间的地方。-确保在传递时间戳时,如果使用了`meta`,那么在回调函数中获取时,要考虑到可能不存在的情况(例如,使用`meta.get(&#39;start_time&#39;,None)`,然后判断是否为`None`)。-一个常见的做法是在传递时间时,确保不会传递`None`值。例如,在发起请求时设置`meta`:```pythonyieldscrapy.Request(url,meta={&#39;start_time&#39;:datetime.datetime.now()})```-在回调函数中处理时:```pythonstart_time=response.meta.get(&#39;start_time&#39;)ifstart_timeisnotNone:elapsed=datetime.datetime.now()-start_time#dosomethingelse:#handlethecasewherestart_timeisnotset```另外,这两个错误可能有关联。比如,第一个错误导致爬虫没有正确启动,进而可能引发第二个错误?但通常它们是独立的。不过,我们按顺序解决。由于用户没有提供具体的代码,我们只能给出一般性的解决方案。下面,我们按照用户的要求,生成相关问题。</think>### Scrapy爬虫启动错误解决方案 您在Scrapy爬虫启动时遇到的两个错误原因如下: #### 错误1:`NameError: name &#39;baidu_spider&#39; is not defined` **原因分析**: 1. 爬虫类未正确导入或定义 2. 爬虫名称拼写错误或不匹配 3. 爬虫文件未放在`spiders`目录中 4. 使用`scrapy crawl`命令时指定了错误的爬虫名称 **解决步骤**: 1. 确认爬虫类定义位置: ```python # 在spiders/baidu_spider.py中正确定义 import scrapy class BaiduSpider(scrapy.Spider): # 类名必须大写驼峰式 name = &#39;baidu_spider&#39; # 爬虫名称需与启动命令一致 # ... ``` 2. 检查启动命令: ```bash # 正确命令(使用name值而非类名) scrapy crawl baidu_spider ``` 3. 若在脚本中启动,确保正确导入: ```python # run.py from scrapy.crawler import CrawlerProcess from scrapy.utils.project import get_project_settings from your_project.spiders.baidu_spider import BaiduSpider # 正确导入路径 process = CrawlerProcess(get_project_settings()) process.crawl(BaiduSpider) # 使用类名而非name字符串 process.start() ``` #### 错误2:`TypeError: unsupported operand type for datetime.datetime and NoneType` **原因分析**: 1. 尝试对`datetime`对象和`None`进行数学运算 2. 常见于下载中间件中计算请求耗时: ```python # 错误示例 start_time = request.meta.get(&#39;start_time&#39;) latency = datetime.now() - start_time # 若start_time为None则报错 ``` **解决步骤**: 1. 添加空值检查: ```python # 在中间件或回调函数中 if start_time is not None: latency = datetime.now() - start_time else: # 处理缺失值情况 self.logger.warning("Missing start_time in request meta") ``` 2. 确保请求正确设置元数据: ```python # 发起请求时设置时间戳 yield scrapy.Request( url, meta={ &#39;start_time&#39;: datetime.now(), # 确保始终设置 # 其他元数据... } ) ``` 3. 使用`get`方法提供默认值: ```python start_time = request.meta.get(&#39;start_time&#39;, datetime.now()) # 即使缺失也能继续执行 ``` ### 完整解决方案示例 ```python # spiders/baidu_spider.py import scrapy from datetime import datetime class BaiduSpider(scrapy.Spider): name = &#39;baidu_spider&#39; def start_requests(self): urls = [&#39;https://www.baidu.com&#39;] for url in urls: yield scrapy.Request( url, meta={&#39;start_time&#39;: datetime.now()}, # 关键:设置初始时间 callback=self.parse ) def parse(self, response): # 安全获取时间戳 start_time = response.meta.get(&#39;start_time&#39;) if start_time: latency = datetime.now() - start_time self.logger.info(f"Request latency: {latency.total_seconds()}s") ``` ### 预防措施 1. **命名规范**: - 爬虫类名:`PascalCase`(如`BaiduSpider`) - 爬虫名称:`snake_case`(如`baidu_spider`) - 保持命名一致性 2. **时间处理最佳实践**: ```python # 在下载中间件中统一处理 class LatencyMiddleware: def process_request(self, request, spider): request.meta.setdefault(&#39;start_time&#39;, datetime.now()) def process_response(self, request, response, spider): start_time = request.meta.get(&#39;start_time&#39;) if start_time: response.meta[&#39;latency&#39;] = datetime.now() - start_time return response ``` 3. **调试建议**: - 使用`scrapy list`命令验证爬虫名称 - 在中间件中添加日志输出: ```python self.logger.debug(f"Request meta: {request.meta.keys()}") ``` > **关键提示**:Scrapy的`meta`字典常用于组件间数据传递,但需要确保设置默认值或进行空值检查,特别是时间戳等可能参与计算的数值[^1]。
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值