mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-08-03 00:23:06 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 6

Implement IDNA (Internationalized Domain Names in Applications).

Browse source
This commit is contained in:
Martin v. Löwis 2003-04-18 10:39:54 +00:00
parent 8d17a90b83
commit 2548c730c1
12 changed files with 1671 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

1
Doc/lib/lib.tex
View file

@ -112,6 +112,7 @@ and how to embed it in other applications.
\input{libtextwrap}
\input{libcodecs}
\input{libunicodedata}
\input{libstringprep}
\input{libmisc} % Miscellaneous Services
\input{libpydoc}

72
Doc/lib/libcodecs.tex
View file

@ -5,7 +5,7 @@
\modulesynopsis{Encode and decode data and streams.}
\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}
\index{Codecs}
@ -809,6 +809,11 @@ listed as operand type in the table.
{byte string}
{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}
{Unicode string}
@ -819,6 +824,11 @@ listed as operand type in the table.
{Unicode string}
{Encoding of PalmOS 3.5}
\lineiv{punycode}
{}
{Unicode string}
{Implements \rfc{3492}. \versionadded{2.3}}
\lineiv{quopri_codec}
{quopri, quoted-printable, quotedprintable}
{byte string}
@ -865,3 +875,63 @@ listed as operand type in the table.
{Compress the operand using gzip}
\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}

134
Doc/lib/libstringprep.tex Normal file
View file

@ -0,0 +1,134 @@
\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}