| :mod:`urlparse` --- Parse URLs into components |
| ============================================== |
| |
| .. module:: urlparse |
| :synopsis: Parse URLs into or assemble them from components. |
| |
| |
| .. index:: |
| single: WWW |
| single: World Wide Web |
| single: URL |
| pair: URL; parsing |
| pair: relative; URL |
| |
| This module defines a standard interface to break Uniform Resource Locator (URL) |
| strings up in components (addressing scheme, network location, path etc.), to |
| combine the components back into a URL string, and to convert a "relative URL" |
| to an absolute URL given a "base URL." |
| |
| The module has been designed to match the Internet RFC on Relative Uniform |
| Resource Locators (and discovered a bug in an earlier draft!). It supports the |
| following URL schemes: ``file``, ``ftp``, ``gopher``, ``hdl``, ``http``, |
| ``https``, ``imap``, ``mailto``, ``mms``, ``news``, ``nntp``, ``prospero``, |
| ``rsync``, ``rtsp``, ``rtspu``, ``sftp``, ``shttp``, ``sip``, ``sips``, |
| ``snews``, ``svn``, ``svn+ssh``, ``telnet``, ``wais``. |
| |
| .. versionadded:: 2.5 |
| Support for the ``sftp`` and ``sips`` schemes. |
| |
| The :mod:`urlparse` module defines the following functions: |
| |
| |
| .. function:: urlparse(urlstring[, default_scheme[, allow_fragments]]) |
| |
| Parse a URL into six components, returning a 6-tuple. This corresponds to the |
| general structure of a URL: ``scheme://netloc/path;parameters?query#fragment``. |
| Each tuple item is a string, possibly empty. The components are not broken up in |
| smaller parts (for example, the network location is a single string), and % |
| escapes are not expanded. The delimiters as shown above are not part of the |
| result, except for a leading slash in the *path* component, which is retained if |
| present. For example:: |
| |
| >>> from urlparse import urlparse |
| >>> o = urlparse('http://www.cwi.nl:80/%7Eguido/Python.html') |
| >>> o |
| ('http', 'www.cwi.nl:80', '/%7Eguido/Python.html', '', '', '') |
| >>> o.scheme |
| 'http' |
| >>> o.port |
| 80 |
| >>> o.geturl() |
| 'http://www.cwi.nl:80/%7Eguido/Python.html' |
| |
| If the *default_scheme* argument is specified, it gives the default addressing |
| scheme, to be used only if the URL does not specify one. The default value for |
| this argument is the empty string. |
| |
| If the *allow_fragments* argument is false, fragment identifiers are not |
| allowed, even if the URL's addressing scheme normally does support them. The |
| default value for this argument is :const:`True`. |
| |
| The return value is actually an instance of a subclass of :class:`tuple`. This |
| class has the following additional read-only convenience attributes: |
| |
| +------------------+-------+--------------------------+----------------------+ |
| | Attribute | Index | Value | Value if not present | |
| +==================+=======+==========================+======================+ |
| | :attr:`scheme` | 0 | URL scheme specifier | empty string | |
| +------------------+-------+--------------------------+----------------------+ |
| | :attr:`netloc` | 1 | Network location part | empty string | |
| +------------------+-------+--------------------------+----------------------+ |
| | :attr:`path` | 2 | Hierarchical path | empty string | |
| +------------------+-------+--------------------------+----------------------+ |
| | :attr:`params` | 3 | Parameters for last path | empty string | |
| | | | element | | |
| +------------------+-------+--------------------------+----------------------+ |
| | :attr:`query` | 4 | Query component | empty string | |
| +------------------+-------+--------------------------+----------------------+ |
| | :attr:`fragment` | 5 | Fragment identifier | empty string | |
| +------------------+-------+--------------------------+----------------------+ |
| | :attr:`username` | | User name | :const:`None` | |
| +------------------+-------+--------------------------+----------------------+ |
| | :attr:`password` | | Password | :const:`None` | |
| +------------------+-------+--------------------------+----------------------+ |
| | :attr:`hostname` | | Host name (lower case) | :const:`None` | |
| +------------------+-------+--------------------------+----------------------+ |
| | :attr:`port` | | Port number as integer, | :const:`None` | |
| | | | if present | | |
| +------------------+-------+--------------------------+----------------------+ |
| |
| See section :ref:`urlparse-result-object` for more information on the result |
| object. |
| |
| .. versionchanged:: 2.5 |
| Added attributes to return value. |
| |
| |
| .. function:: urlunparse(parts) |
| |
| Construct a URL from a tuple as returned by ``urlparse()``. The *parts* argument |
| can be any six-item iterable. This may result in a slightly different, but |
| equivalent URL, if the URL that was parsed originally had unnecessary delimiters |
| (for example, a ? with an empty query; the RFC states that these are |
| equivalent). |
| |
| |
| .. function:: urlsplit(urlstring[, default_scheme[, allow_fragments]]) |
| |
| This is similar to :func:`urlparse`, but does not split the params from the URL. |
| This should generally be used instead of :func:`urlparse` if the more recent URL |
| syntax allowing parameters to be applied to each segment of the *path* portion |
| of the URL (see :rfc:`2396`) is wanted. A separate function is needed to |
| separate the path segments and parameters. This function returns a 5-tuple: |
| (addressing scheme, network location, path, query, fragment identifier). |
| |
| The return value is actually an instance of a subclass of :class:`tuple`. This |
| class has the following additional read-only convenience attributes: |
| |
| +------------------+-------+-------------------------+----------------------+ |
| | Attribute | Index | Value | Value if not present | |
| +==================+=======+=========================+======================+ |
| | :attr:`scheme` | 0 | URL scheme specifier | empty string | |
| +------------------+-------+-------------------------+----------------------+ |
| | :attr:`netloc` | 1 | Network location part | empty string | |
| +------------------+-------+-------------------------+----------------------+ |
| | :attr:`path` | 2 | Hierarchical path | empty string | |
| +------------------+-------+-------------------------+----------------------+ |
| | :attr:`query` | 3 | Query component | empty string | |
| +------------------+-------+-------------------------+----------------------+ |
| | :attr:`fragment` | 4 | Fragment identifier | empty string | |
| +------------------+-------+-------------------------+----------------------+ |
| | :attr:`username` | | User name | :const:`None` | |
| +------------------+-------+-------------------------+----------------------+ |
| | :attr:`password` | | Password | :const:`None` | |
| +------------------+-------+-------------------------+----------------------+ |
| | :attr:`hostname` | | Host name (lower case) | :const:`None` | |
| +------------------+-------+-------------------------+----------------------+ |
| | :attr:`port` | | Port number as integer, | :const:`None` | |
| | | | if present | | |
| +------------------+-------+-------------------------+----------------------+ |
| |
| See section :ref:`urlparse-result-object` for more information on the result |
| object. |
| |
| .. versionadded:: 2.2 |
| |
| .. versionchanged:: 2.5 |
| Added attributes to return value. |
| |
| |
| .. function:: urlunsplit(parts) |
| |
| Combine the elements of a tuple as returned by :func:`urlsplit` into a complete |
| URL as a string. The *parts* argument can be any five-item iterable. This may |
| result in a slightly different, but equivalent URL, if the URL that was parsed |
| originally had unnecessary delimiters (for example, a ? with an empty query; the |
| RFC states that these are equivalent). |
| |
| .. versionadded:: 2.2 |
| |
| |
| .. function:: urljoin(base, url[, allow_fragments]) |
| |
| Construct a full ("absolute") URL by combining a "base URL" (*base*) with |
| another URL (*url*). Informally, this uses components of the base URL, in |
| particular the addressing scheme, the network location and (part of) the path, |
| to provide missing components in the relative URL. For example:: |
| |
| >>> from urlparse import urljoin |
| >>> urljoin('http://www.cwi.nl/%7Eguido/Python.html', 'FAQ.html') |
| 'http://www.cwi.nl/%7Eguido/FAQ.html' |
| |
| The *allow_fragments* argument has the same meaning and default as for |
| :func:`urlparse`. |
| |
| .. note:: |
| |
| If *url* is an absolute URL (that is, starting with ``//`` or ``scheme://``), |
| the *url*'s host name and/or scheme will be present in the result. For example: |
| |
| :: |
| |
| >>> urljoin('http://www.cwi.nl/%7Eguido/Python.html', |
| ... '//www.python.org/%7Eguido') |
| 'http://www.python.org/%7Eguido' |
| |
| If you do not want that behavior, preprocess the *url* with :func:`urlsplit` and |
| :func:`urlunsplit`, removing possible *scheme* and *netloc* parts. |
| |
| |
| .. function:: urldefrag(url) |
| |
| If *url* contains a fragment identifier, returns a modified version of *url* |
| with no fragment identifier, and the fragment identifier as a separate string. |
| If there is no fragment identifier in *url*, returns *url* unmodified and an |
| empty string. |
| |
| |
| .. seealso:: |
| |
| :rfc:`1738` - Uniform Resource Locators (URL) |
| This specifies the formal syntax and semantics of absolute URLs. |
| |
| :rfc:`1808` - Relative Uniform Resource Locators |
| This Request For Comments includes the rules for joining an absolute and a |
| relative URL, including a fair number of "Abnormal Examples" which govern the |
| treatment of border cases. |
| |
| :rfc:`2396` - Uniform Resource Identifiers (URI): Generic Syntax |
| Document describing the generic syntactic requirements for both Uniform Resource |
| Names (URNs) and Uniform Resource Locators (URLs). |
| |
| |
| .. _urlparse-result-object: |
| |
| Results of :func:`urlparse` and :func:`urlsplit` |
| ------------------------------------------------ |
| |
| The result objects from the :func:`urlparse` and :func:`urlsplit` functions are |
| subclasses of the :class:`tuple` type. These subclasses add the attributes |
| described in those functions, as well as provide an additional method: |
| |
| |
| .. method:: ParseResult.geturl() |
| |
| Return the re-combined version of the original URL as a string. This may differ |
| from the original URL in that the scheme will always be normalized to lower case |
| and empty components may be dropped. Specifically, empty parameters, queries, |
| and fragment identifiers will be removed. |
| |
| The result of this method is a fixpoint if passed back through the original |
| parsing function:: |
| |
| >>> import urlparse |
| >>> url = 'HTTP://www.Python.org/doc/#' |
| |
| >>> r1 = urlparse.urlsplit(url) |
| >>> r1.geturl() |
| 'http://www.Python.org/doc/' |
| |
| >>> r2 = urlparse.urlsplit(r1.geturl()) |
| >>> r2.geturl() |
| 'http://www.Python.org/doc/' |
| |
| .. versionadded:: 2.5 |
| |
| The following classes provide the implementations of the parse results:: |
| |
| |
| .. class:: BaseResult |
| |
| Base class for the concrete result classes. This provides most of the attribute |
| definitions. It does not provide a :meth:`geturl` method. It is derived from |
| :class:`tuple`, but does not override the :meth:`__init__` or :meth:`__new__` |
| methods. |
| |
| |
| .. class:: ParseResult(scheme, netloc, path, params, query, fragment) |
| |
| Concrete class for :func:`urlparse` results. The :meth:`__new__` method is |
| overridden to support checking that the right number of arguments are passed. |
| |
| |
| .. class:: SplitResult(scheme, netloc, path, query, fragment) |
| |
| Concrete class for :func:`urlsplit` results. The :meth:`__new__` method is |
| overridden to support checking that the right number of arguments are passed. |
| |