1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
<title>6.4 ZHandler</title>
<META NAME="description" CONTENT="6.4 ZHandler">
<META NAME="keywords" CONTENT="modpython">
<META NAME="resource-type" CONTENT="document">
<META NAME="distribution" CONTENT="global">
<link rel="STYLESHEET" href="modpython.css">
<link rel="first" href="modpython.html">
<link rel="contents" href="contents.html" title="Contents">
<link rel="index" href="genindex.html" title="Index">
<LINK REL="previous" href="hand-httpdapy.html">
<LINK REL="up" href="handlers.html">
<LINK REL="next" href="app-wininst.html">
</head>
<body>
<DIV CLASS="navigation">
<table align="center" width="100%" cellpadding="0" cellspacing="2">
<tr>
<td><A href="hand-httpdapy.html"><img src="icons/previous.gif"
border="0" height="32"
alt="Previous Page" width="32"></A></td>
<td><A href="handlers.html"><img src="icons/up.gif"
border="0" height="32"
alt="Up One Level" width="32"></A></td>
<td><A href="app-wininst.html"><img src="icons/next.gif"
border="0" height="32"
alt="Next Page" width="32"></A></td>
<td align="center" width="100%">Mod_python Manual</td>
<td><A href="contents.html"><img src="icons/contents.gif"
border="0" height="32"
alt="Contents" width="32"></A></td>
<td><img src="icons/blank.gif"
border="0" height="32"
alt="" width="32"></td>
<td><A href="genindex.html"><img src="icons/index.gif"
border="0" height="32"
alt="Index" width="32"></A></td>
</tr></table>
<b class="navlabel">Previous:</b> <a class="sectref" href="hand-httpdapy.html">6.3 Httpdapy handler</A>
<b class="navlabel">Up:</b> <a class="sectref" href="handlers.html">6. Standard Handlers</A>
<b class="navlabel">Next:</b> <a class="sectref" href="app-wininst.html">A. Windows Installation</A>
<br><hr>
</DIV>
<!--End of Navigation Panel-->
<H1><A NAME="SECTION008400000000000000000"> </A>
<BR>
6.4 ZHandler
</H1>
<P>
<b>NOTE:</b> This handler is being phased out in favor of the
<em class="citetitle"><a
href="hand-pub.html"
title="Publisher"
>Publisher</a></em> handler described in
Section <A href="hand-pub.html#hand-pub">6.1</A>.
<P>
This handler allows one to use the Z Object Publisher (formerly Bobo)
with mod_python. This gives you the power of Zope Object Publishing
along with the speed of mod_python. It doesn't get any better than
this!
<P>
WHAT IS ZPublisher?
<P>
ZPublisher is a component of Zope. While I don't profess at Zope
itself as it seems to be designed for different type of users than me,
I do think that the ZPublisher provides an ingeniously simple way of
writing WWW applications in Python.
<P>
A quick example do demonstrate the power of ZPublisher.
<P>
Suppose you had a file called zhello.py like this:
<P>
<dl><dd><pre class="verbatim">
"""A simple Bobo application"""
def sayHello( name = "World" ):
""" Sais Hello (this comment is required)"""
return "Hello %s!" % name
</pre></dl>
<P>
Notice it has one method defined in it. Through ZPublisher, that
method can be invoked through the web via a URL similar to this:
<P>
http://www.domain.tld/site/zhello/sayHello and
<BR>
http://www.domain.tld/site/zhello/sayHello?name=Joe
<P>
Note how the query keyword "name" converted to a keyword argument to
the function.
<P>
If the above didn't "click" for you, go read the ZPublisher
documentation at
http://classic.zope.org:8080/Documentation/Reference/ObjectPublishingIntro
for a more in-depth explanation.
<P>
QUICK START
<P>
<OL>
<LI>Download and install Zope.
<P>
</LI>
<LI>Don't start it. You're only interested in ZPublisher, and in order for
it to work, Zope doesn't need to be running.
<P>
</LI>
<LI>Pick a www directory where you want to use ZPublisher. For our purposes
let's imagine it is accessible via http://www.domain.tld/site.
<P>
</LI>
<LI>Make sure that the FollowSymLinks option is on for this directory
in httpd.conf.
<P>
</LI>
<LI>Make a symlink in this directory to the ZPublisher directory:
<dl><dd><pre class="verbatim">
cd site
ln -s /usr/local/src/Zope-2.1.0-src/lib/python/ZPublisher .
</pre></dl>
<P>
</LI>
<LI>Verify that it is correct:
<dl><dd><pre class="verbatim">
ls -l
lrwxr-xr-x 1 uid group 53 Dec 13 12:15 ZPublisher -> /usr/local/src/Zope-2.1.0-src/lib/python/ZPublisher
</pre></dl>
<P>
</LI>
<LI>Create an <span class="file">.htaccess</span> file with this in it:
<P>
<dl><dd><pre class="verbatim">
SetHandler python-program
PythonHandler mod_python.zhandler
PythonDebug
</pre></dl>
<P>
</LI>
<LI>Create an above mentioned zhello.py file.
<P>
</LI>
<LI>Look at http://www.domain.tld/site/zhello/sayHello?name=Joe
<P>
</LI>
</OL>
<P>
Noteworthy:
<P>
This module automatically reloads modules just like any other
mod_python module. But modules that are imported by your code will not
get reloaded. There are ways around having to restart the server for
script changes to take effect. For example, let's say you have a
module called mycustomlib.py and you have a module that imports it. If
you make a changes to mycustomlib.py, you can force the changes to
take effect by requesting http://www.domain.tld/site/mycustomlib/.
You will get a server error, but mycustomelib should get reloaded.
<P>
P.S.: ZPublisher is not Zope, but only part of it. As of right now, as
far as I know, Zope will not work with mod_python. This is because of
locking issues. Older versions of Zope had no locking, so different
children of apache would corrupt the database by trying to access it
at the same time. Starting with version 2 Zope does have locking,
however, it seems that the first child locks the database without ever
releasing it and after that no other process can access it.
<P>
If this is incorrect, and you can manage to get Zope to work without
problems, please send me an e-mail and I will correct this
documentation.
<DIV CLASS="navigation">
<p><hr>
<table align="center" width="100%" cellpadding="0" cellspacing="2">
<tr>
<td><A href="hand-httpdapy.html"><img src="icons/previous.gif"
border="0" height="32"
alt="Previous Page" width="32"></A></td>
<td><A href="handlers.html"><img src="icons/up.gif"
border="0" height="32"
alt="Up One Level" width="32"></A></td>
<td><A href="app-wininst.html"><img src="icons/next.gif"
border="0" height="32"
alt="Next Page" width="32"></A></td>
<td align="center" width="100%">Mod_python Manual</td>
<td><A href="contents.html"><img src="icons/contents.gif"
border="0" height="32"
alt="Contents" width="32"></A></td>
<td><img src="icons/blank.gif"
border="0" height="32"
alt="" width="32"></td>
<td><A href="genindex.html"><img src="icons/index.gif"
border="0" height="32"
alt="Index" width="32"></A></td>
</tr></table>
<b class="navlabel">Previous:</b> <a class="sectref" href="hand-httpdapy.html">6.3 Httpdapy handler</A>
<b class="navlabel">Up:</b> <a class="sectref" href="handlers.html">6. Standard Handlers</A>
<b class="navlabel">Next:</b> <a class="sectref" href="app-wininst.html">A. Windows Installation</A>
<hr>
<span class="release-info">Release 2.7.10, documentation updated on December 07, 2003.</span>
</DIV>
<!--End of Navigation Panel-->
</BODY>
</HTML>
|
