Errata

My familiarity with XML is not very high (this book), but an XML example you give
contradicts XML formatting described earlier in the book.

You text:
<names>
<name first="Chris" last="Jones"/>
<name/>
</names>

What I think it should be:
<names>
<name first="Chris" last="Jones">
</name>
</names>

The ending slash in an element is for elements that only have one tag, while in this
example you are trying to show an element with two tags that is empty.

The code after line
pyFile.close()
is incorrectly indented. The if statement and the last statement should be at the
same level as the first line of code.

the first import line in his file fails with standard Pyton 2.2.1 distribution.
Searching reveals there is no module xml.dom.ext. Same problem in Example 4-3.

In the first "if self.author:" conditional, the subsequent "s =" statement, intended
to be conditionally executed, is not indented as required by Python.

The variable "POSTING_FORM" is HTTP method is "POST", but attribute of "action" has
"GET" method.

I fiexed to:

POSTING_FORM = '''
<form method="POST" action="start.cgi">
<p>
Title: <br><input type="text" length="40" name="title"><br>
Contributor:<br><input type="text" length="40" name="contrib"><br>
Author: <br><input type="text" length="40" name="author"><br>
Contents: <br><textarea rows="15" cols="80" name="contents"></textarea><br>
<input type="hidden" name="cmd" value="pd">
<input type="submit">
</form>
'''

(also Example 6.8) To establish a stylesheet and transform it to a html string, you
have to do:

xsltproc.appendStylesheetUri("story.xsl")
html = xsltproc.runUri("story.xml")

But due to an error in XSLT of PyXML, the appendStylesheetUri() is broken and you can
not run this programme.

In example 7-9 (flatfile.cgi), CGI captures the flat file from HTTP request and
present it on the browser. To get the flat file the following statement is used:

flatfile = query.getvalue("flatfile","")[0]

flatfile contains only a '#'. To get the whole form you have to discard [0]. In other
words here is the [0] superfluous. It means the above statement in correct form would
be:

flatfile = query.getvalue("flatfile","")

[164/165] In FlatfileParser class on line "if ':' in line:";
if ':' in line:

should be

if ':' not in line:

since this condition is checking for a blank line or rather any line without a :

The XMP tag should not be used. It was obsolete already in early HTML drafts prior to
HTML 2.0, and remained obsolete in HTML 2.0, HTML 3.2 and HTML 4. The XML code could
be presented as HTML by PrettyPrinting it in a StringIO and then calling cgi.escape
on it. (On p. 174 also.)

My PyXML's (0.7.1) version of PrettyPrint returns XML processing directives like

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE CustomerProfile SYSTEM "CustomerProfile.dtd">

at the top of the text. When the XML switch gets this and creates a DOM from XML
(bottom of p. 272) it raises an exception:

SAXParseException: <unknown>:8:13: xml processing instruction not at start of
external entity

This is because the XML processing directives get stuck in the middle of the message
inside the <response></response> tags.

To fix it, I changed on p.236

PrettyPrint(newdoc, strXML)

to

PrettyPrint(newdoc.documentElement, strXML)

This gets rid of the XML processing directives.

processXMLMessagePost removes all occurrences of "n=". Should only remove the leading
two characters. (current code breaks XML that has any attributes whose name ends with
an n.)

The docstring refers to some older version of the code (on p. 271 also)

The replacement of "n=" replaces all occurrences, which is incorrect.
Could change
msg.setXMLMessage(unquote_plus(strPostData).replace("n=",""))
into:
msg.setXMLMessage(unquote_plus(strPostData.replace("n=","")))

While strPostData is in its encoded form, it cannot contain more than the leading
occurrence of "n=".

qs.get("mode", "") should be qs.get("mode", [""]), and similarly for id. Or perhaps
they should be written like qs.get("mode", [""])[0] to avoid repeated indexing later.

The indexing in qs.get(something, "")[0] fails, if qs.get returns the default value
"": the default should be [""] instead.

The code would also look nicer as a loop:

for field in ("firstname", "lastname", "address1", "address2",
"city", "state", "zip"):
value = qs.get(field, [""])[0].strip()
xmlmsg += "<%>%</%s>
" % (field, value, field)