#
# html_util
#
# Utility functions to generate (basic) HTML output from CGI
# scripts.
#
# author: Asfandyar Qureshi
# copying: MIT license
import sys
HTML_HEADER=\
"""
<html>
<head>
<title>
%s
</title>
<META HTTP-EQUIV="pragma" CONTENT="no-cache">
<style>
<!--
body {
background-color: #ffffff;
font-family: verdana, arial, helvetica, sans-serif;
}
div { font-size: 13px; }
p { font-size: 13px; }
ol { font-size: 13px; }
ul { font-size: 13px; }
h1 { font-size: 24px; font-weight: bold; }
h2 { font-size: 18px; font-weight: bold; border-bottom: 2px solid #000000; }
h3 { font-size: 15px; font-weight: bold; }
pre {
font-family: "courier new", courier, mono;
color: #400040;
font-size: 13px;
font-weight: bold;
}
li { list-style: square; }
div {
padding-left:16px;
padding-top:8px;
padding-bottom:8px;
padding-right:16px;
text-align: left
}
div.white {
border: 1px solid #bbbbbb;
background: #ffffff;
}
div.gray {
border: 1px solid #bbbbbb;
background: #eeeeee;
}
div.yellow {
border: 1px solid #bbbbbb;
background: #ffffe4;
}
div.green {
border: 1px solid #bbbbbb;
background: #ddffaa;
}
div.orange {
border: 1px solid #bbbbbb;
background: #ffe787;
}
div.purple {
border: 1px solid #000000;
color: #ffffff;
background: #491c3d;
}
div.darkred {
border: 1px solid #000000;
color: #ffffff;
background: #8a0a0a;
}
div.darkgray {
border: 1px solid #000000;
color: #ffffff;
background: #aaaaaa;
}
div.black {
color: #ffffff;
background: #000000;
}
//-->
</style>
</head>
<body>
<div style="padding-right: 32px; padding-left: 32px;">
"""
HTML_FOOTER=\
"""
</div>
</body>
</html>
"""
class HTMLDocument:
"""
A HTML document.
Provides functions for constructing a HTML documents with stylized text,
forms, and images. Also provides functions for outputting that HTML
from a CGI script.
"""
# body : list of strings (represents a HTML fragment)
def __init__(self, title):
"""
Creates an empty HTML document with the given title.
"""
self.body = [HTML_HEADER % title]
def print_html(self):
"""
Outputs the HTML.
requires:
for valid HTML, all begun tags should be ended.
"""
if not self.body[-1] == HTML_FOOTER: # make sure HTML footer is there
self.body.append(HTML_FOOTER)
#print 'Content-type: text/html\n\n'
sys.stdout.write('Content-type: text/html\n\n')
for fragment in self.body:
sys.stdout.write(fragment)
#print fragment,
def _was_printed(self):
"""
Returns True if print_html has been called at least once,
False otherwise.
"""
return (self.body[-1] == HTML_FOOTER)
#
# helper functions
#
def _add_html_escapes(self, text):
text = text.replace('&', '&')
text = text.replace('"', '"')
text = text.replace("'", ''')
text = text.replace('<', '<')
text = text.replace('>', '>')
return text
#
# basic text stuff
#
def write_text(self, text, color=None, size=None, bold=False, italic=False, underlined=False, typewriter=False):
"""
Writes a fragment of formatted text.
The following formatting options exist:
color: string (e.g., 'red', 'blue', 'orange', or html hex '#ffffff'
size: string (e.g., '12px', '10pt')
bold: boolean
italic: boolean
typewriter: boolean
"""
html=""
# add format tags
if bold: html += "<b>"
if italic: html += "<i>"
if underlined: html += "<u>"
if typewriter: html += "<tt>"
# style (size + color)
if size or color:
html += "<font style='"
if size: html += "font-size: %s;" % str(size)
if color: html += "color: %s;" % str(color)
html += "'>"
# HTML escapes
text = self._add_html_escapes(text)
# add text
html += text
# close style
if size or color:
html += "</font>"
# close format tags
if typewriter: html += "</tt>"
if underlined: html += "</u>"
if italic: html += "</i>"
if bold: html += "</b>"
# add to document
self.body.append(html)
def write_pre_text(self, text):
"""
Write pre-formatted text (e.g., python code).
"""
html ="<pre>%s</pre>" % text
self.body.append(html)
def new_paragraph(self):
"""
Starts a new paragraph in the HTML.
"""
self.body.append("\n<p>\n")
def newline(self):
self.body.append("<br>\n")
def new_section(self, section_title):
"""
Starts a new section in the HTML.
"""
txt = self._add_html_escapes(section_title)
self.body.append("\n<h1>%s</h1>\n" % txt)
def new_subsection(self, section_title):
"""
Starts a new sub-section in the HTML.
"""
txt = self._add_html_escapes(section_title)
self.body.append("\n<h2>%s</h2>\n" % txt)
def new_subsubsection(self, section_title):
"""
Starts a new sub-sub-section in the HTML.
"""
txt = self._add_html_escapes(section_title)
self.body.append("\n<h3>%s</h3>\n" % txt)
#
# divs and align
#
def begin_center(self):
"""
Begin a block horizontally centered.
You will need to call end_center.
"""
self.body.append("\n<center>\n")
def end_center(self):
"""
Begin a block horizontally centered.
You will need to call end_center.
"""
self.body.append("\n</center>\n")
def begin_div_block(self, type=None, width=None):
"""
Begin a division with some specific formatting style
and width.
valid values for type:
None: white background, no borders
'white': white backround box
'gray': light gray background box
'yellow': pale yellow background box
'green': green background box
'orange': orange background box
'purple': dark purple box with white text
'darkred': dark red background box, white foreground
'darkgray':dark gray background box, white foreground
'black': black background box, white foreground
width: in percent or pixels (string), e.g., 100% or 100px
"""
if type:
type = str(type)
if not type in ['white', 'gray', 'yellow', 'green', 'orange', 'purple', 'darkred', 'darkgray', 'black']:
raise ValueError(type)
html = "\n<div"
if type: html += " class='%s'" % type
if width: html += " style='width:%s'" % str(width)
html += ">\n"
self.body.append(html)
def end_div_block(self):
self.body.append("\n</div>\n")
#
# lists
#
def write_numbered_list(self, list):
"""
Adds the elements of the list as a numbered list,
with each element on a new line.
"""
html="\n<ol>\n"
for item in list:
txt = self._add_html_escapes(str(item))
html += "<li>%s</li>\n" % txt
html += "</ol>\n"
self.body.append(html)
def write_bullet_list(self, list):
"""
Adds the elements of the list as a bullet-ed list,
with each element on a new line.
"""
html="\n<ul>\n"
for item in list:
txt = self._add_html_escapes(str(item))
html += "<li>%s</li>\n" % txt
html += "</ul>\n"
self.body.append(html)
#
# links
#
def begin_linked_part(self, link_url):
"""
Starts a part of the HTML that links to another document.
You will need to call end_linked_part.
"""
self.body.append("<a href='%s'>" % link_url)
def end_linked_part(self):
"""
Ends a link.
"""
self.body.append("</a>")
#
# images
#
def add_image(self, image_url, image_text=None, image_width=None, image_height=None):
"""
Adds an image with some descriptive text,
in case the image cannot be loaded.
image_width, image_height: (string) pixels or percent, e.g. 150px or 70%
"""
html = "\n<img src='%s'" % image_url
if image_text: html += " alt='%s'" % str(image_text)
if image_width: html += " width='%s'" % str(image_width)
if image_height: html += " height='%s'" % str(image_height)
html += ">\n"
self.body.append(html)
#
# forms
#
def begin_form(self, action):
"""
Begins a form. You can add as many inputs to the form as you
want, but you must eventually end the form
action:
the action to undertake when the user submits the form.
action can either be 'mailto:' followed by an email address,
or it can be the name of a script that will be invoked
with a HTTP post.
"""
if action[:7].lower() == 'mailto:':
self.body.append("\n<form action='%s' method='post' enctype='text/plain'>\n" % action)
else:
self.body.append("\n<form action='%s' method='post' enctype='multipart/form-data'>\n" % action)
def end_form(self):
self.body.append("\n</form>")
def form_add_button_submit(self, button_caption="Submit"):
html = "<input type='submit' value='%s'>\n" % button_caption
self.body.append(html)
def form_add_button_reset(self, button_caption="Reset"):
html = "<input type='reset' value='%s'>" % button_caption
self.body.append(html)
def form_add_field_text(self, id, default_value="", size="60"):
"""
A text field accepts a single-line text input from the user. This
is useful for asking the user for things like email and names, etc.
default_value: initial text
size: width of text box, in characters
"""
default_value = self._add_html_escapes(default_value)
html="<input type='text' name='%s' value='%s'>\n" % (id, str(default_value))
self.body.append(html)
def form_add_field_checkbox(self, id, checked=False):
"""
A checkbox field is either true or false.
"""
html="<input type='checkbox' name='%s'" % id
if checked: html += " checked"
html += ">\n"
self.body.append(html)
def form_add_field_textarea(self, id, rows=5, cols=60, default_value=""):
"""
A text-area field accepts a multi-line text input. This is useful
for asking more open-ended questions, e.g., comments.
"""
default_value = self._add_html_escapes(default_value)
html="<textarea name='%s' rows='%s' cols='%s'>\n%s\n</textarea>\n" % (id, str(rows), str(cols), str(default_value))
self.body.append(html)
def form_add_field_multichoice(self, id, choice_id=[], choices=[], selected=None, newlines=True):
"""
Adds a multiple choice field, as a set of radio inputs.
requires: len(choice_id) == len(choices)
choice_id:
the internal identifier for each option. this indentifier
will show up in the submitted form.
choices:
the text displayed for each choice
selected:
None
or the choice_id that should be initially selected
newlines:
if this is True, each option is on a new line.
"""
html=""
for i in range(len(choice_id)):
txt = self._add_html_escapes(choices[i])
#html += "<input type='radio' name='%s' value='%s'> %s" % (id, str(choice_id[i]), txt)
html += "<input type='radio' name='%s' value='%s'" % (id, str(choice_id[i]))
if choice_id[i] == selected: html += " checked"
html += "> %s" % txt
if newlines: html += "<br>\n"
self.body.append(html)
def form_add_field_dropdown_choice(self, id, choice_id=[], choices=[]):
"""
Adds a multiple choice field, as a drop-down list.
requires: len(choice_id) == len(choices)
choice_id:
the internal identifier for each option. this indentifier
will show up in the submitted form.
choices:
the text displayed for each choice
"""
html="<select name='%s'>" % id
for i in range(len(choice_id)):
txt = self._add_html_escapes(choices[i])
html += "<option value='%s'>%s</option>\n" % (str(choice_id[i]), txt)
html += "</select>\n"
self.body.append(html)
def form_add_field_file(self, id, size="40"):
"""
Adds a field that the user can use to upload a file.
"""
html="<input type='file' name='%s' size='%s'" % (id, str(size))
self.body.append(html)