在我使用URLSession.dataTask(with:completionHandler:)创建新的会话数据任务并通过调用其<IfModule mod_ssl.c>
<VirtualHost *:443>
# The ServerName directive sets the request scheme, hostname and port that
# the server uses to identify itself. This is used when creating
# redirection URLs. In the context of virtual hosts, the ServerName
# specifies what hostname must appear in the request's Host: header to
# match this virtual host. For the default virtual host (this file) this
# value is not decisive as it is used as a last resort host regardless.
# However, you must set it for any further virtual host explicitly.
ServerName www.orderfetchers.com
ServerAdmin webmaster@localhost
DocumentRoot /var/www/html
# Available loglevels: trace8, ..., trace1, debug, info, notice, warn,
# error, crit, alert, emerg.
# It is also possible to configure the loglevel for particular
# modules, e.g.
#LogLevel info ssl:warn
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
# For most configuration files from conf-available/, which are
# enabled or disabled at a global level, it is possible to
# include a line for only one particular virtual host. For example the
# following line enables the CGI configuration for this host only
# after it has been globally disabled with "a2disconf".
#Include conf-available/serve-cgi-bin.conf
Alias /static /home/abdul/Fetchors/static
<Directory /home/abdul/Fetchors/static>
Require all granted
</Directory>
Alias /media /home/abdul/Fetchors/media
<Directory /home/abdul/Fetchors/media>
Require all granted
</Directory>
<Directory /home/abdul/Fetchors/Fetchors>
<Files wsgi.py>
Require all granted
</Files>
</Directory>
WSGIScriptAlias / /home/abdul/Fetchors/Fetchors/wsgi.py
WSGIDaemonProcess django_app python-path=/home/abdul/Fetchors python-home=/home/abdul/Fetchors/venv
WSGIProcessGroup django_app
Include /etc/letsencrypt/options-ssl-apache.conf
SSLCertificateFile /etc/letsencrypt/live/www.orderfetchers.com/fullchain.pem
SSLCertificateKeyFile /etc/letsencrypt/live/www.orderfetchers.com/privkey.pem
</VirtualHost>
</IfModule>
方法来启动任务之后，鉴于该应用程序在请求运行时不会崩溃，对我来说是否安全假设resume()（传递给上面的completionHandler）最终总是只会被调用一次，即使网络请求（例如连接断开）或应用程序（例如，进入后台）？
注意：我没有在任务上显式调用URLSession.dataTask(with:completionHandler:)或cancel()。只是suspend()。
我想知道这个问题的答案，因为（正在我的应用程序的主线程中）我正在创建并启动（一个接一个）多个异步网络请求，并且想知道最后一个请求何时完成。
具体地说，我正在开发一个具有名为resume()的自定义类的应用程序。在启动时，该应用程序（假设它找到了存储在Account中的帐户访问令牌）仅创建该类的一个实例，并将其存储到一个名为UserDefaults的全局变量（跨整个应用程序），该变量代表该应用程序的当前登录帐户。
我已将名为account（例如）的var（实例）存储属性添加到Account，并默认将其设置为pendingGetFooRequestCount。每次调用0（一种实例方法）时，我都会在Account.getFoo()上添加1（在调用pendingGetFooRequestCount之前）。在resume()内部（传递给completionHandler和（为了安全起见）在传递给URLSession.dataTask(with:completionHandler:)的闭包内部，我首先从DispatchQueue.main.async()中减去1，然后检查是否{ {1}}等于pendingGetFooRequestCount。如果是这样，我知道上一个get-foo请求已完成，因此我可以调用另一种方法来继续流程。
我的逻辑如何？会按预期工作吗？我应该以其他方式这样做吗？另外，我是否甚至需要在主线程上减少pendingGetFooRequestCount？
答案 0 :(得分：1)
URLRequest具有timeoutInterval属性，其默认值为60秒。如果此时没有响应，则以非nil错误调用完成。