应用程序引擎:调试和运行不同(神秘)

Question

我正在构建一个wiki，当调试期间的结果似乎与程序运行期间的结果不同时，我遇到了一个问题。

class WikiPage(Handler):
    def get(self, id):
            id, existing_article, article_content = self.get_stripped_id_article_content(id)
            logging.error(("GET! id: {0}; article: {1}; content: {2}").format(id, existing_article, article_content))
            <...>

    def strip_id(self, id):
            id = id.replace("/", "")
            return id

    def get_stripped_id_article_content(self, id):
        id = self.strip_id(id)
        q = Article.all()
        q.filter("id = ", id)
        existing_article = q.get()

        content = existing_article.content if existing_article else ""

        return id, existing_article, content
    <...>

class CreateEditPage(WikiPage):
    def post(self, id):
        id, existing_article, article_content = self.get_stripped_id_article_content(id)
        user = self.get_user(self.request)

        input_content = self.request.get("content")

        if existing_article:
            existing_article.content = input_content
            existing_article.put()

        else:            
            new_article = Article(id = id, content = input_content)
            new_article.put()
            id, existing_article, article_content = self.get_stripped_id_article_content(id)
            logging.error(("POST! In Else. id: {0}; article: {1}; content: {2}").format(id, existing_article, article_content))



        id, existing_article, article_content = self.get_stripped_id_article_content(id)
        logging.error(("POST! Outside Else. id: {0}; article: {1}; content: {2}").format(id, existing_article, article_content))
        self.redirect("/" + str(id))

PAGE_RE = r'(/(?:[a-zA-Z0-9_-]+/?)*)'
app = webapp2.WSGIApplication([('/_edit' + PAGE_RE, CreateEditPage),
                               (PAGE_RE, WikiPage),
                               ],
                              debug=True)

首先，我清除了数据库中的所有内容，并清除了memcache。

我运行我的申请：

INFO     2015-10-14 21:06:52,744 sdk_update_checker.py:229] Checking for updates to the SDK.
INFO     2015-10-14 21:06:53,135 api_server.py:205] Starting API server at: http://localhost:53588
INFO     2015-10-14 21:06:53,141 dispatcher.py:197] Starting module "default" running at: http://localhost:8080
INFO     2015-10-14 21:06:53,142 admin_server.py:118] Starting admin server at: http://localhost:8000
ERROR    2015-10-14 21:10:10,804 gmv_wiki.py:194] GET! id: ; article: None; content: 
INFO     2015-10-14 21:10:10,810 module.py:809] default: "GET / HTTP/1.1" 302 -
INFO     2015-10-14 21:10:10,847 module.py:809] default: "GET /_edit/ HTTP/1.1" 200 348
ERROR    2015-10-14 21:10:12,228 gmv_wiki.py:194] GET! id: newpost; article: None; content: 
INFO     2015-10-14 21:10:12,239 module.py:809] default: "GET /newpost HTTP/1.1" 302 -
INFO     2015-10-14 21:10:12,264 module.py:809] default: "GET /_edit/newpost HTTP/1.1" 200 348
ERROR    2015-10-14 21:10:18,945 gmv_wiki.py:194] GET! id: new_article; article: None; content: 
INFO     2015-10-14 21:10:18,951 module.py:809] default: "GET /new_article HTTP/1.1" 302 -
INFO     2015-10-14 21:10:18,976 module.py:809] default: "GET /_edit/new_article HTTP/1.1" 200 348
ERROR    2015-10-14 21:10:50,979 gmv_wiki.py:246] POST! In Else. id: new_article; article: None; content: 
ERROR    2015-10-14 21:10:50,985 gmv_wiki.py:251] POST! Outside Else. id: new_article; article: None; content: 
INFO     2015-10-14 21:10:50,991 module.py:809] default: "POST /_edit/new_article HTTP/1.1" 302 -
ERROR    2015-10-14 21:10:51,014 gmv_wiki.py:194] GET! id: new_article; article: None; content: 
INFO     2015-10-14 21:10:51,022 module.py:809] default: "GET /new_article HTTP/1.1" 302 -
INFO     2015-10-14 21:10:51,051 module.py:809] default: "GET /_edit/new_article HTTP/1.1" 200 348
ERROR    2015-10-14 21:11:18,321 gmv_wiki.py:251] POST! Outside Else. id: new_article; article: <gmv_wiki.Article object at 0x7f684d2ba250>; content: New article content.
INFO     2015-10-14 21:11:18,326 module.py:809] default: "POST /_edit/new_article HTTP/1.1" 302 -
ERROR    2015-10-14 21:11:18,351 gmv_wiki.py:194] GET! id: new_article; article: <gmv_wiki.Article object at 0x7f684d2663d0>; content: New article content.
INFO     2015-10-14 21:11:18,358 module.py:809] default: "GET /new_article HTTP/1.1" 200 262

我调试我的应用程序：

pydev debugger: starting (pid: 10230)
INFO     2015-10-14 21:12:24,730 sdk_update_checker.py:229] Checking for updates to the SDK.
INFO     2015-10-14 21:12:25,435 api_server.py:205] Starting API server at: http://localhost:44302
INFO     2015-10-14 21:12:25,463 dispatcher.py:197] Starting module "default" running at: http://localhost:8080
INFO     2015-10-14 21:12:25,467 admin_server.py:118] Starting admin server at: http://localhost:8000
pydev debugger: starting (pid: 10250)
ERROR    2015-10-14 21:12:36,523 gmv_wiki.py:194] GET! id: new_article_1; article: None; content: 
INFO     2015-10-14 21:12:36,547 module.py:809] default: "GET /new_article_1 HTTP/1.1" 302 -
INFO     2015-10-14 21:12:36,766 module.py:809] default: "GET /_edit/new_article_1 HTTP/1.1" 200 348
ERROR    2015-10-14 21:12:54,394 gmv_wiki.py:246] POST! In Else. id: new_article_1; article: None; content: 
ERROR    2015-10-14 21:12:54,430 gmv_wiki.py:251] POST! Outside Else. id: new_article_1; article: None; content: 
INFO     2015-10-14 21:12:54,452 module.py:809] default: "POST /_edit/new_article_1 HTTP/1.1" 302 -
ERROR    2015-10-14 21:12:54,587 gmv_wiki.py:194] GET! id: new_article_1; article: <gmv_wiki.Article object at 0x7fad181bef10>; content: New article 1 content.
INFO     2015-10-14 21:12:54,610 module.py:809] default: "GET /new_article_1 HTTP/1.1" 200 266

您能看看代码中logging.error的情况吗？以及日志中的结果。

两种绝对平等的情况。文章 #普通运行1 #调试

该程序的行为如下: 1.在调试过程中一切正常:为一篇新文章创建编辑表单，当我按下"Submit“键时，内容被放置到数据库中，并被重定向到该文章的wiki页面。2.当我只运行程序(而不是调试程序)时，打开一篇新文章的编辑表单，输入一些内容并按下"Submit“。然后我被重定向到wiki页面。在那个地址找不到wiki页面。我被重定向到编辑页面。然后，当我再次输入内容时，内容最终被放入数据库，wiki页面就会打开。

对我来说，谜团是: 1.为什么运行和调试之间有区别? 2.为什么在我完成new_article.put()之后，在post函数中仍然找不到文章对象? 3。然后我被重定向到wiki页面，不知怎么找到了文章对象。真奇怪。4.为什么existing_article.put()工作得很好，而new_article.put()不向数据库放置任何东西？

好吧，我好像是在胡思乱想。你能帮我解决这些问题吗？谢谢你的建议。

Answer 1

我怀疑您正在遇到GAE数据存储最终一致性问题。基本上，在new_article.put()中保存的一篇新文章在Article.all()查询中(通常是短)中找不到。您仍然可以通过id、tho访问它，但是您必须为此调整代码。

我怀疑行为上的差异是因为调试模式执行的总体速度较低，这可能隐藏最终的一致性问题。