netrc —- netrc file processing

Source code:Lib/netrc.py

The netrc class parses and encapsulates the netrc file format used bythe Unix ftp program and other FTP clients.

  • class netrc.netrc([file])
  • A netrc instance or subclass instance encapsulates data from a netrcfile. The initialization argument, if present, specifies the file to parse. Ifno argument is given, the file .netrc in the user's home directory —as determined by os.path.expanduser() — will be read. Otherwise,a FileNotFoundError exception will be raised.Parse errors will raise NetrcParseError with diagnosticinformation including the file name, line number, and terminating token.If no argument is specified on a POSIX system, the presence of passwords inthe .netrc file will raise a NetrcParseError if the fileownership or permissions are insecure (owned by a user other than the userrunning the process, or accessible for read or write by any other user).This implements security behavior equivalent to that of ftp and otherprograms that use .netrc.

在 3.4 版更改: Added the POSIX permission check.

在 3.7 版更改: os.path.expanduser() is used to find the location of the.netrc file when file is not passed as argument.

  • exception netrc.NetrcParseError
  • Exception raised by the netrc class when syntactical errors areencountered in source text. Instances of this exception provide threeinteresting attributes: msg is a textual explanation of the error,filename is the name of the source file, and lineno gives theline number on which the error was found.

netrc Objects

A netrc instance has the following methods:

  • netrc.authenticators(host)
  • Return a 3-tuple (login, account, password) of authenticators for host.If the netrc file did not contain an entry for the given host, return the tupleassociated with the 'default' entry. If neither matching host nor default entryis available, return None.
  • netrc.repr()
  • Dump the class data as a string in the format of a netrc file. (This discardscomments and may reorder the entries.)

Instances of netrc have public instance variables:

  • netrc.hosts
  • Dictionary mapping host names to (login, account, password) tuples. The'default' entry, if any, is represented as a pseudo-host by that name.
  • netrc.macros
  • Dictionary mapping macro names to string lists.

注解

Passwords are limited to a subset of the ASCII character set. All ASCIIpunctuation is allowed in passwords, however, note that whitespace andnon-printable characters are not allowed in passwords. This is a limitationof the way the .netrc file is parsed and may be removed in the future.