[Python-checkins] python/dist/src/Doc/lib libstringprep.tex,NONE,1.1 lib.tex,1.218,1.219 libcodecs.tex,1.17,1.18
loewis@users.sourceforge.net
loewis@users.sourceforge.net
Fri, 18 Apr 2003 03:40:23 -0700
Update of /cvsroot/python/python/dist/src/Doc/lib
In directory sc8-pr-cvs1:/tmp/cvs-serv18193/Doc/lib
Modified Files:
lib.tex libcodecs.tex
Added Files:
libstringprep.tex
Log Message:
Implement IDNA (Internationalized Domain Names in Applications).
--- NEW FILE: libstringprep.tex ---
\section{\module{stringprep} ---
Internet String Preparation}
\declaremodule{standard}{stringprep}
\modulesynopsis{String preparation, as per RFC 3453}
\moduleauthor{Martin v. L\"owis}{martin@v.loewis.de}
\sectionauthor{Martin v. L\"owis}{martin@v.loewis.de}
When identifying things (such as host names) in the internet, it is
often necessary to compare such identifications for
``equality''. Exactly how this comparison is executed may depend on
the application domain, e.g. whether it should be case-insensitive or
not. It may be also necessary to restrict the possible
identifications, to allow only identifications consisting of
``printable'' characters.
\rfc{3454} defines a procedure for ``preparing'' Unicode strings in
internet protocols. Before passing strings onto the wire, they are
processed with the preparation procedure, after which they have a
certain normalized form. The RFC defines a set of tables, which can be
combined into profiles. Each profile must define which tables it uses,
and what other optional parts of the \code{stringprep} procedure are
part of the profile. One example of a \code{stringprep} profile is
\code{nameprep}, which is used for internationalized domain names.
The module \module{stringprep} only exposes the tables from RFC
3454. As these tables would be very large to represent them as
dictionaries or lists, the module uses the Unicode character database
internally. The module source code itself was generated using the
\code{mkstringprep.py} utility.
As a result, these tables are exposed as functions, not as data
structures. There are two kinds of tables in the RFC: sets and
mappings. For a set, \module{stringprep} provides the ``characteristic
function'', i.e. a function that returns true if the parameter is part
of the set. For mappings, it provides the mapping function: given the
key, it returns the associated value. Below is a list of all functions
available in the module.
\begin{funcdesc}{in_table_a1}{code}
Determine whether \var{code} is in table{A.1} (Unassigned code points
in Unicode 3.2).
\end{funcdesc}
\begin{funcdesc}{in_table_b1}{code}
Determine whether \var{code} is in table{B.1} (Commonly mapped to
nothing).
\end{funcdesc}
\begin{funcdesc}{map_table_b2}{code}
Return the mapped value for \var{code} according to table{B.2}
(Mapping for case-folding used with NFKC).
\end{funcdesc}
\begin{funcdesc}{map_table_b3}{code}
Return the mapped value for \var{code} according to table{B.3}
(Mapping for case-folding used with no normalization).
\end{funcdesc}
\begin{funcdesc}{in_table_c11}{code}
Determine whether \var{code} is in table{C.1.1}
(ASCII space characters).
\end{funcdesc}
\begin{funcdesc}{in_table_c12}{code}
Determine whether \var{code} is in table{C.1.2}
(Non-ASCII space characters).
\end{funcdesc}
\begin{funcdesc}{in_table_c11_c12}{code}
Determine whether \var{code} is in table{C.1}
(Space characters, union of C.1.1 and C.1.2).
\end{funcdesc}
\begin{funcdesc}{in_table_c21}{code}
Determine whether \var{code} is in table{C.2.1}
(ASCII control characters).
\end{funcdesc}
\begin{funcdesc}{in_table_c22}{code}
Determine whether \var{code} is in table{C.2.2}
(Non-ASCII control characters).
\end{funcdesc}
\begin{funcdesc}{in_table_c21_c22}{code}
Determine whether \var{code} is in table{C.2}
(Control characters, union of C.2.1 and C.2.2).
\end{funcdesc}
\begin{funcdesc}{in_table_c3}{code}
Determine whether \var{code} is in table{C.3}
(Private use).
\end{funcdesc}
\begin{funcdesc}{in_table_c4}{code}
Determine whether \var{code} is in table{C.4}
(Non-character code points).
\end{funcdesc}
\begin{funcdesc}{in_table_c5}{code}
Determine whether \var{code} is in table{C.5}
(Surrogate codes).
\end{funcdesc}
\begin{funcdesc}{in_table_c6}{code}
Determine whether \var{code} is in table{C.6}
(Inappropriate for plain text).
\end{funcdesc}
\begin{funcdesc}{in_table_c7}{code}
Determine whether \var{code} is in table{C.7}
(Inappropriate for canonical representation).
\end{funcdesc}
\begin{funcdesc}{in_table_c8}{code}
Determine whether \var{code} is in table{C.8}
(Change display properties or are deprecated).
\end{funcdesc}
\begin{funcdesc}{in_table_c9}{code}
Determine whether \var{code} is in table{C.9}
(Tagging characters).
\end{funcdesc}
\begin{funcdesc}{in_table_d1}{code}
Determine whether \var{code} is in table{D.1}
(Characters with bidirectional property ``R'' or ``AL'').
\end{funcdesc}
\begin{funcdesc}{in_table_d2}{code}
Determine whether \var{code} is in table{D.2}
(Characters with bidirectional property ``L'').
\end{funcdesc}
Index: lib.tex
===================================================================
RCS file: /cvsroot/python/python/dist/src/Doc/lib/lib.tex,v
retrieving revision 1.218
retrieving revision 1.219
diff -C2 -d -r1.218 -r1.219
*** lib.tex 9 Apr 2003 01:39:06 -0000 1.218
--- lib.tex 18 Apr 2003 10:39:50 -0000 1.219
***************
*** 113,116 ****
--- 113,117 ----
\input{libcodecs}
\input{libunicodedata}
+ \input{libstringprep}
\input{libmisc} % Miscellaneous Services
Index: libcodecs.tex
===================================================================
RCS file: /cvsroot/python/python/dist/src/Doc/lib/libcodecs.tex,v
retrieving revision 1.17
retrieving revision 1.18
diff -C2 -d -r1.17 -r1.18
*** libcodecs.tex 31 Jan 2003 17:19:04 -0000 1.17
--- libcodecs.tex 18 Apr 2003 10:39:50 -0000 1.18
***************
*** 6,10 ****
\moduleauthor{Marc-Andre Lemburg}{mal@lemburg.com}
\sectionauthor{Marc-Andre Lemburg}{mal@lemburg.com}
!
\index{Unicode}
--- 6,10 ----
\moduleauthor{Marc-Andre Lemburg}{mal@lemburg.com}
\sectionauthor{Marc-Andre Lemburg}{mal@lemburg.com}
! \sectionauthor{Martin v. L\"owis}{martin@v.loewis.de}
\index{Unicode}
***************
*** 810,813 ****
--- 810,818 ----
{Convert operand to hexadecimal representation, with two digits per byte}
+ \lineiv{idna}
+ {}
+ {Unicode string}
+ {Implements \rfc{3490}. \versionadded{2.3}. See also \module{encodings.idna}}
+
\lineiv{mbcs}
{dbcs}
***************
*** 820,823 ****
--- 825,833 ----
{Encoding of PalmOS 3.5}
+ \lineiv{punycode}
+ {}
+ {Unicode string}
+ {Implements \rfc{3492}. \versionadded{2.3}}
+
\lineiv{quopri_codec}
{quopri, quoted-printable, quotedprintable}
***************
*** 866,867 ****
--- 876,937 ----
\end{tableiv}
+
+ \subsection{\module{encodings.idna} ---
+ Internationalized Domain Names in Applications}
+
+ \declaremodule{standard}{encodings.idna}
+ \modulesynopsis{Internationalized Domain Names implementation}
+ \moduleauthor{Martin v. L\"owis}
+
+ This module implements \rfc{3490} (Internationalized Domain Names in
+ Applications) and \rfc{3492} (Nameprep: A Stringprep Profile for
+ Internationalized Domain Names (IDN)). It builds upon the
+ \code{punycode} encoding and \module{stringprep}. \versionadded{2.3}
+
+ These RFCs together define a protocol to support non-ASCII characters
+ in domain names. A domain name containing non-ASCII characters (such
+ as ``www.Alliancefran\,caise.nu'') is converted into an
+ ASCII-compatible encoding (ACE, such as
+ ``www.xn--alliancefranaise-npb.nu''). The ACE form of the domain name
+ is then used in all places where arbitrary characters are not allowed
+ by the protocol, such as DNS queries, HTTP \code{Host:} fields, and so
+ on. This conversion is carried out in the application; if possible
+ invisible to the user: The application should transparently convert
+ Unicode domain labels to IDNA on the wire, and convert back ACE labels
+ to Unicode before presenting them to the user.
+
+ Python supports this conversion in several ways: The \code{idna} codec
+ allows to convert between Unicode and the ACE. Furthermore, the
+ \module{socket} module transparently converts Unicode host names to
+ ACE, so that applications need not be concerned about converting host
+ names themselves when they pass them to the socket module. On top of
+ that, modules that have host names as function parameters, such as
+ \module{httplib} and \module{ftplib}, accept Unicode host names
+ (\module{httplib} then also transparently sends an IDNA hostname in
+ the \code{Host:} field if it sends that field at all).
+
+ When receiving host names from the wire (such as in reverse name
+ lookup), no automatic conversion to Unicode is performed: Applications
+ wishing to present such host names to the user should decode them to
+ Unicode.
+
+ The module \module{encodings.idna} also implements the nameprep
+ procedure, which performs certain normalizations on host names, to
+ achieve case-insensitivity of international domain names, and to unify
+ similar characters. The nameprep functions can be used directly if
+ desired.
+
+ \begin{funcdesc}{nameprep}{label}
+ Return the nameprepped version of \var{label}. The implementation
+ currently assumes query strings, so \code{AllowUnassigned} is
+ true.
+ \end{funcdesc}
+
+ \begin{funcdesc}{ToASCCII}{label}
+ Convert a label to ASCII, as specified in \rfc{3490}.
+ \code{UseSTD3ASCIIRules} is assumed to be false.
+ \end{funcdesc}
+
+ \begin{funcdesc}{ToUnicode}{label}
+ Convert a label to Unicode, as specified in \rfc{3490}.
+ \end{funcdesc}