/Doc/library/webbrowser.rst

  1
  2:mod:`webbrowser` --- Convenient Web-browser controller
  3=======================================================
  4
  5.. module:: webbrowser
  6   :synopsis: Easy-to-use controller for Web browsers.
  7.. moduleauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
  8.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
  9
 10
 11The :mod:`webbrowser` module provides a high-level interface to allow displaying
 12Web-based documents to users. Under most circumstances, simply calling the
 13:func:`open` function from this module will do the right thing.
 14
 15Under Unix, graphical browsers are preferred under X11, but text-mode browsers
 16will be used if graphical browsers are not available or an X11 display isn't
 17available.  If text-mode browsers are used, the calling process will block until
 18the user exits the browser.
 19
 20If the environment variable :envvar:`BROWSER` exists, it is interpreted to
 21override the platform default list of browsers, as a os.pathsep-separated list
 22of browsers to try in order.  When the value of a list part contains the string
 23``%s``, then it is  interpreted as a literal browser command line to be used
 24with the argument URL substituted for ``%s``; if the part does not contain
 25``%s``, it is simply interpreted as the name of the browser to launch. [1]_
 26
 27For non-Unix platforms, or when a remote browser is available on Unix, the
 28controlling process will not wait for the user to finish with the browser, but
 29allow the remote browser to maintain its own windows on the display.  If remote
 30browsers are not available on Unix, the controlling process will launch a new
 31browser and wait.
 32
 33The script :program:`webbrowser` can be used as a command-line interface for the
 34module. It accepts an URL as the argument. It accepts the following optional
 35parameters: :option:`-n` opens the URL in a new browser window, if possible;
 36:option:`-t` opens the URL in a new browser page ("tab"). The options are,
 37naturally, mutually exclusive.
 38
 39The following exception is defined:
 40
 41
 42.. exception:: Error
 43
 44   Exception raised when a browser control error occurs.
 45
 46The following functions are defined:
 47
 48
 49.. function:: open(url[, new=0[, autoraise=1]])
 50
 51   Display *url* using the default browser. If *new* is 0, the *url* is opened in
 52   the same browser window if possible.  If *new* is 1, a new browser window is
 53   opened if possible.  If *new* is 2, a new browser page ("tab") is opened if
 54   possible.  If *autoraise* is true, the window is raised if possible (note that
 55   under many window managers this will occur regardless of the setting of this
 56   variable).
 57
 58   Note that on some platforms, trying to open a filename using this function,
 59   may work and start the operating system's associated program.  However, this
 60   is neither supported nor portable.
 61
 62   .. versionchanged:: 2.5
 63      *new* can now be 2.
 64
 65
 66.. function:: open_new(url)
 67
 68   Open *url* in a new window of the default browser, if possible, otherwise, open
 69   *url* in the only browser window.
 70
 71
 72.. function:: open_new_tab(url)
 73
 74   Open *url* in a new page ("tab") of the default browser, if possible, otherwise
 75   equivalent to :func:`open_new`.
 76
 77   .. versionadded:: 2.5
 78
 79
 80.. function:: get([name])
 81
 82   Return a controller object for the browser type *name*.  If *name* is empty,
 83   return a controller for a default browser appropriate to the caller's
 84   environment.
 85
 86
 87.. function:: register(name, constructor[, instance])
 88
 89   Register the browser type *name*.  Once a browser type is registered, the
 90   :func:`get` function can return a controller for that browser type.  If
 91   *instance* is not provided, or is ``None``, *constructor* will be called without
 92   parameters to create an instance when needed.  If *instance* is provided,
 93   *constructor* will never be called, and may be ``None``.
 94
 95   This entry point is only useful if you plan to either set the :envvar:`BROWSER`
 96   variable or call :func:`get` with a nonempty argument matching the name of a
 97   handler you declare.
 98
 99A number of browser types are predefined.  This table gives the type names that
100may be passed to the :func:`get` function and the corresponding instantiations
101for the controller classes, all defined in this module.
102
103+-----------------------+-----------------------------------------+-------+
104| Type Name             | Class Name                              | Notes |
105+=======================+=========================================+=======+
106| ``'mozilla'``         | :class:`Mozilla('mozilla')`             |       |
107+-----------------------+-----------------------------------------+-------+
108| ``'firefox'``         | :class:`Mozilla('mozilla')`             |       |
109+-----------------------+-----------------------------------------+-------+
110| ``'netscape'``        | :class:`Mozilla('netscape')`            |       |
111+-----------------------+-----------------------------------------+-------+
112| ``'galeon'``          | :class:`Galeon('galeon')`               |       |
113+-----------------------+-----------------------------------------+-------+
114| ``'epiphany'``        | :class:`Galeon('epiphany')`             |       |
115+-----------------------+-----------------------------------------+-------+
116| ``'skipstone'``       | :class:`BackgroundBrowser('skipstone')` |       |
117+-----------------------+-----------------------------------------+-------+
118| ``'kfmclient'``       | :class:`Konqueror()`                    | \(1)  |
119+-----------------------+-----------------------------------------+-------+
120| ``'konqueror'``       | :class:`Konqueror()`                    | \(1)  |
121+-----------------------+-----------------------------------------+-------+
122| ``'kfm'``             | :class:`Konqueror()`                    | \(1)  |
123+-----------------------+-----------------------------------------+-------+
124| ``'mosaic'``          | :class:`BackgroundBrowser('mosaic')`    |       |
125+-----------------------+-----------------------------------------+-------+
126| ``'opera'``           | :class:`Opera()`                        |       |
127+-----------------------+-----------------------------------------+-------+
128| ``'grail'``           | :class:`Grail()`                        |       |
129+-----------------------+-----------------------------------------+-------+
130| ``'links'``           | :class:`GenericBrowser('links')`        |       |
131+-----------------------+-----------------------------------------+-------+
132| ``'elinks'``          | :class:`Elinks('elinks')`               |       |
133+-----------------------+-----------------------------------------+-------+
134| ``'lynx'``            | :class:`GenericBrowser('lynx')`         |       |
135+-----------------------+-----------------------------------------+-------+
136| ``'w3m'``             | :class:`GenericBrowser('w3m')`          |       |
137+-----------------------+-----------------------------------------+-------+
138| ``'windows-default'`` | :class:`WindowsDefault`                 | \(2)  |
139+-----------------------+-----------------------------------------+-------+
140| ``'internet-config'`` | :class:`InternetConfig`                 | \(3)  |
141+-----------------------+-----------------------------------------+-------+
142| ``'macosx'``          | :class:`MacOSX('default')`              | \(4)  |
143+-----------------------+-----------------------------------------+-------+
144
145Notes:
146
147(1)
148   "Konqueror" is the file manager for the KDE desktop environment for Unix, and
149   only makes sense to use if KDE is running.  Some way of reliably detecting KDE
150   would be nice; the :envvar:`KDEDIR` variable is not sufficient.  Note also that
151   the name "kfm" is used even when using the :program:`konqueror` command with KDE
152   2 --- the implementation selects the best strategy for running Konqueror.
153
154(2)
155   Only on Windows platforms.
156
157(3)
158   Only on Mac OS platforms; requires the standard MacPython :mod:`ic` module.
159
160(4)
161   Only on Mac OS X platform.
162
163Here are some simple examples::
164
165   url = 'http://www.python.org'
166
167   # Open URL in a new tab, if a browser window is already open.
168   webbrowser.open_new_tab(url + '/doc')
169
170   # Open URL in new window, raising the window if possible.
171   webbrowser.open_new(url)
172
173
174.. _browser-controllers:
175
176Browser Controller Objects
177--------------------------
178
179Browser controllers provide these methods which parallel two of the module-level
180convenience functions:
181
182
183.. method:: controller.open(url[, new[, autoraise=1]])
184
185   Display *url* using the browser handled by this controller. If *new* is 1, a new
186   browser window is opened if possible. If *new* is 2, a new browser page ("tab")
187   is opened if possible.
188
189
190.. method:: controller.open_new(url)
191
192   Open *url* in a new window of the browser handled by this controller, if
193   possible, otherwise, open *url* in the only browser window.  Alias
194   :func:`open_new`.
195
196
197.. method:: controller.open_new_tab(url)
198
199   Open *url* in a new page ("tab") of the browser handled by this controller, if
200   possible, otherwise equivalent to :func:`open_new`.
201
202   .. versionadded:: 2.5
203
204
205.. rubric:: Footnotes
206
207.. [1] Executables named here without a full path will be searched in the
208       directories given in the :envvar:`PATH` environment variable.