The syntax of socket "host-pattern" entries follows these rules:

• <host-pattern> := <host> | ':' <port> | <host> ':' <port>
• <host> := '*' | '*.' <anychar except '/' and '*'>+
• <port> := '*' | <port number between 1 and 65535>)

Matches if the host name of the URL contains a specified string. To test whether a host name component has a prefix 'foo', use hostContains: '.foo'. This matches 'www.foobar.com' and 'foo.com', because an implicit dot is added at the beginning of the host name. Similarly, hostContains can be used to match against component suffix ('foo.') and to exactly match against components ('.foo.'). Suffix- and exact-matching for the last components need to be done separately using hostSuffix, because no implicit dot is added at the end of the host name.

Domain values must be lowercase ASCII. Use punycode to encode non-ASCII characters.

Add the * character before the domain name to match the domain and any subdomains. For instance, *webkit.org matches bugs.webkit.org and webkit.org.