"""A totally object-oriented way of writing HTML. Each
element is a object which may contain other HTML
elements (ie. objects). Only those elements allowed
in HTML to contain each other are allowed to be
inserted.
Print or str() or .output() the top (root) object
to get the final HTML."""
# $Id: forgetHTML.py,v 1.4 2003/10/08 15:03:58 stain Exp $
#
# (c) Stian Soiland 2001-2003
# Licence: LGPL
#
# Last changes:
# $Log: forgetHTML.py,v $
# Revision 1.4 2003/10/08 15:03:58 stain
# Dirty hack0rz.. allowing existing class for rows
#
# Revision 1.3 2003/09/11 22:37:51 stain
# a new compare-function, let things be sorted
#
# A NonIndentMixin to prevent indention on certain
# elements
#
# SimpleTable.add now supports TableCells, even with their own
# colspan - this is done in a very dirty way, but prevents
# expansion in these cases:
#
# t = SimpleTable()
# t.add("Col1", "Col2")
# t.add(html.TableCell("Both columns", colspan=2))
#
# Strong, Emphasis, Small, Big, Break added.
#
#
# Textarea and Pre now don't indent by using NonIndentMixin.
#
# Revision 1.2 2003/06/25 11:45:37 stain
# Added SimpleTable - a nice way to create a
# description-list-type table (ie. with first row
# or column as headers)
#
# TODO? Both row and column!
#
# Revision 1.1 2003/06/23 08:16:07 stain
# now getitem (ie element['blapp']) would refer to attributes on item,
# not retrieve subelements.
#
# Revision 1.1 2003/01/18 05:29:15 stain
# First import from aapningstider.no
#
# Revision 1.5 2002/10/16 11:22:22 stain
# wohoo
#
# Revision 1.4 2002/08/13 00:00:54 stain
# Now without those stupid bugs.
#
# Revision 1.3 2002/08/11 22:22:36 stain
#
# Jay. Added two classes, QuickForm and SimpleDocument.
# QuickForm is a nifty way of creating SIMPLE forms.
#
# SimpleDocument is a way of getting started with a document,
# creating , , , <h1> and optionnally a
# stylesheet reference.
#
# Jah, and Label was added.
#
# Revision 1.2 2002/08/11 22:21:56 stain
# Jay. Added two classes, QuickForm and SimpleDocument.
#
# QuickForm is a nifty way of creating SIMPLE forms.
#
# SimpleDocument is a way of getting started with a document,
# creating <head>, <body>, <title>, <h1> and optionnally a
# stylesheet reference.
#
# Revision 1.1 2002/07/18 23:12:02 stain
# Akkai
#
# Revision 1.13 2001/11/07 01:49:47 stain
# Støtte for å slå opp (rekursivt) id-tagger med element.get("id")
# eller element["id"].
#
# Ie.
#
# body = html.Body()
# div = html.Division(id="overskrift")
# body.append(div)
# body["overskrift"] == div
#
# body["overskrift"].append(html.Header("Hei", id="blapp"))
#
# body["blapp"].attributes["style"] = "align: right;"
#
# Blapp - bør gjerne skrives om til å bruke bredde-først-søk
# istedet for dybde-først for effektivitetens skyld
# (hvis man søker i et element man tror key-en ligger direkte
# under), på den andre siden er dybde-først tilsvarende en
# topp-til-bunn-søk i en flat HTML-fil.
#
# Revision 1.12 2001/04/07 10:39:32 stain
# Header did not set level correct
#
# Revision 1.11 2001/04/06 19:37:20 stain
# Formfields. Support for some stuff. stylesheet. Wraps attribute lists.
#
# Revision 1.10 2001/04/02 19:22:24 stain
# Støtte for ruler <hr> og tittel <title>
#
# Revision 1.9 2001/03/20 23:22:26 stain
# Small errors in indentation fixed.
#
# Protected methods should NOT be used for __define_*, as these
# are called by superclass methods! Now uses _define_*.
#
# Use self._content instead of self.content to indicate this
# is a 'privat' (but not protected) variable.
#
# Revision 1.8 2001/03/15 00:34:53 stain
# Don't use __method__ anymore for private
# methods, this was nasty. Using __method now.
#
# As well: raising ElementNotAllowed with
# element.__class__.__name__ makes a much
# nicer output.
#
# (Previous code printed out the HTML
# of the object not allowed!)
#
# Revision 1.7 2001/03/13 23:01:29 stain
# Added some nice meta information on top
#
#
# Note:
# + Only a few elements are supported at this time.
# + Currently all possible attributes are allowed
# (modify element.attributes or simply include them
# as keywords in constructor call)
# Todo:
# + Form elements!
import exceptions, types
indention = ' ' * 2 # Use two spaces for indention in HTML output
class HTMLError(exceptions.Exception):
"""General HTML error"""
def __str__(self):
args = exceptions.Exception.__str__(self) # Get our arguments
return self.__doc__ + ': ' + args
class ElementNotAllowedError(HTMLError):
"""Element not allowed"""
pass
class AbstractClassError(HTMLError):
"""Abstract class"""
pass
class HeaderLevelOutOfRangeError(HTMLError):
"""Header level out of range (1-6)"""
pass
class Element:
tag = None # this would be 'p' for <p>, etc.
def __init__(self, *add, **attributes):
self._content = []
self.attributes = attributes # might be {} :=)
self.allowed_content = self._define_allowed()
self.default_child = self._define_default()
self.extend(add)
# _class means the class attribute. We need to
# 'escape' this to avoid the Python keyword class
if(self.attributes.has_key('_class')):
# Rename it!
self['class'] = self['_class']
del self.attributes['_class']
def __cmp__(self, other):
# Sort (recursive) by content
if isinstance(other, Element):
return cmp(self._content, other._content)
else:
return cmp(self._content, other)
def _define_allowed(self):
"""Override this method to specify allowed content"""
return [Flow] # list of classes of elements
# The reason for using a seperate function for this
# is to make it possible to allow classes that have
# not yet been declared at the point of parsing
def _define_default(self):
"""Override this method to specify an element
class wrapper to be tried if not matched by isallowed"""
return None
def _check_abstract(self):
"""Checks if our class is capable of producing HTML"""
# If self.tag is not set, this is not a real
# HTML-element for use by append or __str__
if(self.tag == None): # we allow '' as a tag (used by Text)
raise AbstractClassError, self.__class__.__name__
def __str__(self):
return self.output()
def output(self, indent=0):
# returns the HTML-formatted output, nicely indented
self._check_abstract()
result = indention * indent + '<' + self.tag
# Each attribute in the form key="value"
count = -1
for (attribute,value) in self.attributes.items():
count += 1
if(not count % 2 and count): # Not the first time!
result = result + '\n' + indention * indent + ' ' * (len(self.tag) + 1)
result = result + ' %s="%s"' % (attribute,value)
if(not self._content):
result = result + ' />\n' # No content!
else:
result = result + '>\n'
for element in self._content:
result = result + element.output(indent+1) # increased indent level
# end tag
result = result + indention * indent + '</' + self.tag + '>\n'
return result
def get(self, key):
"""Finds a sub-element by it's id. Fun part: recursive! """
if(key == self.attributes.get('id')):
return self # simplest case
for item in self._content:
match = item.get(key)
if(match):
return match
return None # No match
def __getitem__(self, key):
return self.attributes.__getitem__(key)
def __setitem__(self, key, value):
self.attributes.__setitem__(key, value)
def isallowed(self,element):
"""Checks if the given given element is allowed within ourself"""
for allowed in self.allowed_content:
if(isinstance(element,allowed)):
return 1
return 0 # None of those allowed matched
def extend(self, list):
"""Appends each element in the given list"""
for element in list:
self.append(element)
def append(self, element):
"""Appends the given element within this element"""
self._check_abstract()
if(type(element) in (types.StringType, types.LongType, types.IntType, types.FloatType)):
# For easy adding of text and numbers, we make a text
# element
element = Text(element)
if(not self.isallowed(element)):
if(type(self.default_child) == types.ClassType):
element = self.default_child(element) # No further checks
else:
raise ElementNotAllowedError, repr(element)
self._content.append(element)
def set(self, element):
"""Replaces the content with this new element, if it's allowed"""
old = self._content
self._content = []
try:
self.append(element)
except Exception, e:
self_content = old # Restore!
raise e
class Document(Element):
tag = 'html'
def _define_allowed(self):
return [Head, Body]
def output(self, indent=0):
result = """<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
"""
return result + Element.output(self, indent)
class Head(Element):
tag = 'head'
def _define_allowed(self):
return [HeadStuff]
class HeadStuff(Element):
pass
class Meta(HeadStuff):
tag = 'meta'
def _define_allowed(self):
return []
class Link(HeadStuff):
tag = 'link'
def _define_allowed(self):
return []
class NonIndentMixin:
def output(self, indent=0):
indent = -999
return Element.output(self, indent)
# <link href="/stylesheet.css" rel="stylesheet" type="text/css" />
class Stylesheet(Link):
def __init__(self, href, media=None):
if(media):
Link.__init__(self,
rel='stylesheet',
type='text/css',
href=href,
media=media)
else:
Link.__init__(self,
rel='stylesheet',
type='text/css',
href=href)
class Title(HeadStuff):
tag = 'title'
def _define_allowed(self):
return [Text]
class Body(Element):
tag = 'body'
class Flow(Element):
pass
class Block(Flow):
pass
class Inline(Flow):
def _define_allowed(self):
return [Inline]
class Text(Inline):
"""Special class for plain text"""
tag = ''
def _define_allowed(self):
return []
def isallowed(self,element):
# Only strings and numbers are allowed. Unicode not supported (yet)
if(type(element) in (types.StringType, types.LongType, types.IntType, types.FloatType)):
return 1
else:
return 0
def get(self, key):
"""Finds a sub-element by it's id. Fun part: recursive! """
if(key == self.attributes.get('id')):
return self # simplest case
else:
return None
# We don't want to search our _content
def append(self, element):
# Overriding this method is very important,
# otherwise Text('blapp') would loop forever :)
if(not self.isallowed(element)):
raise ElementNotAllowedError, element
self._content.append(element)
def output(self, indent=0):
result = ''
for line in self._content:
result = result + indention * indent + str(line) + '\n'
# Question: What would be the right thing to do here?
# Is it acceptable to allow several entries in self._content?
# Shoult they be seperated by ' ', '\n' or '' in output?
return result
class List(Block):
def _define_allowed(self):
return [ListItem]
def _define_default(self):
return ListItem
class UnorderedList(List):
tag = 'ul'
class OrderedList(List):
tag = 'ol'
class ListItem(Element):
tag = 'li'
class Table(Block):
tag = 'table'
def _define_allowed(self):
return [TableRow]
def _define_default(self):
return TableRow
def extend2(self, lists):
"""Inserts each array in lists as a row in the table"""
for list in lists:
row = TableRow()
row.extend(list)
self.append(row)
class TableRow(Element):
tag = 'tr'
def _define_allowed(self):
return [TableCell]
def _define_default(self):
return TableCell
class TableCell(Element):
tag = 'td'
class TableHeader(TableCell):
tag = 'th'
class SimpleTable(Table):
def __init__(self, header="column", *args, **kwargs):
"""header -- "column" or "row"
if column, the first column will be indexed (TableHeader),
if "row", the first row will be indexed.
if "both", both the first row and column will be indexed.
Anything else (like None) - no index"""
Table.__init__(self, *args, **kwargs)
self._items = []
self._width=0
self.header = header
def add(self, *args, **kwargs):
self._content = [] # reset html version because we changed..!
row = (kwargs,) + args
self._width = max(self._width, self._rowWidth(row))
rowWidth = self._rowWidth(row)
self._items.append(row)
def _getColSpan(self, cell):
# Eh.. we need to substract colspans..
if isinstance(cell, TableCell):
try:
# *cough* *cough*
colspan = cell['colspan']
colspan = int(colspan)
return colspan
except KeyError:
return 1
except ValueError:
return 1
return 1
def _rowWidth(self, row):
rowWidth = 0
for cell in row[1:]:
rowWidth += self._getColSpan(cell)
return rowWidth
def _extendRow(self, row):
"""Extends a row if needed, but skip the kwargs in pos 0"""
rowWidth = self._rowWidth(row)
extendWidth = self._width - rowWidth
# skip first element, and extend
return list(row[1:]) + [''] * extendWidth
def _generateContent(self):
if not self._items:
pass
items = self._items
if self.header in ("row", "both"):
row=items.pop(0)
kwargs = row[0]
row = self._extendRow(row)
tablerow = TableRow(**kwargs)
self.append(tablerow)
pos = 0
for column in row:
cssClass = "col%s" % pos
if not isinstance(column, TableCell):
column = TableHeader(column)
try:
column['class'] = column['class'] + ' ' + cssClass
except KeyError:
column['class'] = cssClass
tablerow.append(column)
pos += self._getColSpan(column)
even = True
for row in items:
even = not even #ooo, flipz colorstylz
kwargs = row[0]
row = self._extendRow(row)
tablerow = TableRow(**kwargs)
try:
_class = tablerow['class'] + " "
except KeyError:
_class = ""
tablerow['class'] = _class + (even and 'even' or 'odd')
self.append(tablerow)
pos = 0
cssClass = "col%s" % pos
column = row[0]
if not isinstance(column, TableCell):
if self.header in ("column", "both"):
column = TableHeader(column)
else:
column = TableCell(column)
try:
column['class'] = column['class'] + ' ' + cssClass
except KeyError:
column['class'] = cssClass
tablerow.append(column)
pos += self._getColSpan(column)
for column in row[1:]:
cssClass = "col%s" % pos
if not isinstance(column, TableCell):
column = TableCell(column)
try:
column['class'] = column['class'] + ' ' + cssClass
except KeyError:
column['class'] = cssClass
tablerow.append(column)
pos += self._getColSpan(column)
def output(self, *args, **kwargs):
if not self._content:
self._generateContent()
return Table.output(self, *args, **kwargs)
class Division(Block):
tag = 'div'
class Span(Inline):
tag = 'span'
class Strong(Inline):
tag = 'strong'
class Emphasis(Inline):
tag = 'em'
class Small(Inline):
tag = 'small'
class Big(Inline):
tag = 'big'
class Header(Block):
def _define_allowed(self):
return [Inline]
def __init__(self, add=None, level=1, **kargs):
self.set_level(level)
if(add):
Block.__init__(self, add, **kargs)
else:
Block.__init__(self, **kargs)
def set_level(self, level):
if((level >= 1) and (level <= 6)):
self.level = level
self.tag = 'h' + str(self.level)
else:
raise HeaderLevelOutOfRangeError, level
class Paragraph(Block):
tag = 'p'
def _define_allowed(self):
return [Inline]
class Pre(NonIndentMixin, Block):
tag = 'pre'
def _define_allowed(self):
return [Inline]
class Break(Inline):
tag = 'br'
def _define_allowed(self):
return []
class Image(Inline):
tag = 'img'
def _define_allowed(self):
return []
class Anchor(Inline):
tag = 'a'
def _define_allowed(self):
return [Inline]
class Ruler(Block):
tag = 'hr'
def _define_allowed(self):
return []
class Form(Block):
tag = 'form'
def _define_allowed(self):
return [Flow]
class Input(Inline):
tag = 'input'
def _define_allowed(self):
return []
class Select(Inline):
tag = 'select'
def _define_allowed(self):
return [OptGroup, Option]
class OptGroup(Element):
tag = 'optgroup'
def _define_allowed(self):
return [Option]
class Option(Element):
tag = 'option'
def _define_allowed(self):
return [Text]
class Submit(Input):
def __init__(self, value=None, *args, **kargs):
if(value <> None):
Input.__init__(self, type='submit', value=value, *args, **kargs)
else:
Input.__init__(self, type='submit', *args, **kargs)
class Checkbox(Input):
def __init__(self, *args, **kargs):
Input.__init__(self, type='checkbox', *args, **kargs)
class Radiobutton(Input):
def __init__(self, *args, **kargs):
Input.__init__(self, type='radiobutton', *args, **kargs)
class Textfield(Input):
def __init__(self, *args, **kargs):
Input.__init__(self, type='text', *args, **kargs)
class Hidden(Input):
def __init__(self, *args, **kargs):
Input.__init__(self, type='hidden', *args, **kargs)
class Textarea(Inline, NonIndentMixin):
tag = 'textarea'
class Label(Inline):
tag = 'label'
def _define_allowed(self):
return [Inline]
class SimpleDocument(Document):
"""A handy default document with a title and
optionally a specified external stylesheet. You
may change the title or stylesheet later on using
the methods setTitle() and setStylesheet()."""
def __init__(self, title=None, stylesheet=None):
Document.__init__(self)
self.head = Head()
self.body = Body()
self.append(self.head)
self.append(self.body)
self.title = None
self.header = None
self.stylesheet = None
if(title):
self.setTitle(title)
if(stylesheet):
self.setStylesheet(stylesheet)
def setTitle(self, title):
if not self.title:
self.title = Title()
self.head.append(self.title)
if not self.header:
self.header = Header()
self.body.append(self.header)
self.title.set(title)
self.header.set(title)
def setStylesheet(self, url):
if not self.stylesheet:
self.stylesheet = Stylesheet(url)
self.head.append(self.stylesheet)
self.stylesheet['href'] = url
class SimpleForm(Form):
"""A simple way to create an easy form.
form = SimpleForm()
form.addText('firstname', 'First name', 'John')
form.addText('lastname', 'Last name')
choices = [
('red', 'Red color'),
('blue', 'Blue color'),
('green', 'Greenish color')
]
form.addChoices('color', choices, 'Select a color',
'red')
"""
def __init__(self, **kwargs):
Form.__init__(self, **kwargs)
def addText(self, id, description=None, value=None):
"""Adds a textfield, optionallly with a label."""
div = Division()
self.append(div)
if(description):
label = Label(description)
label['for'] = id
div.append(label)
if(value):
div.append(Textfield(id=id, name=id, value=value))
else:
div.append(Textfield(id=id, name=id))
def addChoices(self, id, choices, description=None,
default=None):
"""Adds a selection box for the given choices.
Note that the choices parameter must be a sequence of
bi-tupples (key, description).
"""
div = Division()
self.append(div)
label = Label(description)
label['for'] = id
select = Select(id=id, name=id)
for (key, desc) in choices:
option = Option(desc, id=key, value=key)
if(key == default):
option['selected'] = 'selected'
select.append(option)
div.append(label)
div.append(select)