1 Introduction
2 ------------
3
4 WebStack is a package which provides a common API for Python Web
5 applications, regardless of the underlying server or framework environment.
6 It should be possible with WebStack to design and implement an application,
7 to choose a deployment environment, and then to be able to deploy the
8 application in a different environment later on without having to go back
9 and rewrite substantial parts of the application.
10
11 Quick Start
12 -----------
13
14 Try running the demo:
15
16 python tools/demo.py
17
18 An introductory guide to creating applications can be found in the docs
19 directory - see docs/index.html for the start page.
20
21 Contact, Copyright and Licence Information
22 ------------------------------------------
23
24 The current Web page for WebStack at the time of release is:
25
26 http://www.boddie.org.uk/python/WebStack.html
27
28 Copyright and licence information can be found in the docs directory - see
29 docs/COPYING.txt, docs/LICENCE.txt and docs/LICENCE-PyServlet.txt for more
30 information.
31
32 Framework Support
33 -----------------
34
35 Currently, BaseHTTPRequestHandler (via BaseHTTPServer in the standard
36 library), CGI, Jython/Java Servlet API, mod_python, Twisted, Webware, WSGI
37 and Zope 2 are supported. Each framework has its own set of strengths and
38 weaknesses, but the idea is that deployment concerns can be considered
39 separately from the implementation of application functionality. Consult the
40 NOTES.txt files in each framework's subdirectory of the docs directory for
41 some notes on how applications may be run in each environment.
42
43 Tested Frameworks Release Information
44 ----------------- -------------------
45
46 BaseHTTPRequestHandler Python 2.2.2, Python 2.3.3, Python 2.4.1
47 CGI Apache 2.0.44, Apache 2.0.53, AOLserver 4.0.10, lighttpd 1.3.15
48 Jython/Java Servlet API Jython 2.1, Java JDK 1.3.1_02, Tomcat 4.1.27 (Servlet 2.3)
49 mod_python 3.0.3 (3.1.3 for framework cookie and session support)
50 Twisted 1.0.5, 1.3.0
51 Webware 0.8.1, CVS (2004-02-06)
52 WSGI run_with_cgi (PEP 333)
53 Zope 2.7.2-0, 2.8.0-final
54
55 New in WebStack 1.0 (Changes since WebStack 0.10)
56 -------------------------------------------------
57
58 Added Debian package support.
59 Added automatic session directory creation for the WebStack sessions
60 implementation.
61 Fixed the calendar example, making it perform a proper function.
62
63 New in WebStack 0.10 (Changes since WebStack 0.9)
64 -------------------------------------------------
65
66 Changes to make the tools/demo.py script work on Windows (and other) platforms
67 (suggested by Jim Madsen).
68 Fixed end of header newlines for CGI (suggested by Matt Harrison).
69 Minor documentation fixes and improvements, adding information on AOLserver in
70 the CGI and Webware notes.
71 Changed the mod_python server name method to use the server object rather than
72 the connection object.
73 Added a parameter to the ResourceMap.MapResource class to permit automatic
74 redirects into resource hierarchies when no trailing "/" was given in the URL;
75 changed the updated virtual path info so that empty values may be set (the
76 guarantee that "/" will always appear no longer applies).
77 Fixed virtual path info retrieval when the value is an empty string.
78
79 New in WebStack 0.9 (Changes since WebStack 0.8)
80 ------------------------------------------------
81
82 Standardised error handling in the adapters so that tracebacks can be
83 suppressed and an internal server error condition raised.
84 Added overriding of path info in transactions.
85 Added a ResourceMap resource for dispatching to different resources
86 according to path components.
87 Standardised deployment for some frameworks (see docs/deploying.html).
88 Introductory documentation in XHTML format.
89 Added server name and port methods to the transaction.
90 Added a simple demonstration application, incorporating many of the examples
91 and launched under a single script.
92 Fixed mod_python native sessions.
93 Fixed Zope request stream access.
94 WebStack is now licensed under the LGPL - see docs/COPYING.txt for details.
95
96 New in WebStack 0.8 (Changes since WebStack 0.7)
97 ------------------------------------------------
98
99 Added a standard exception, EndOfResponse, which can be used to immediately
100 stop the processing/production of a response; this is useful when resources
101 need to issue a redirect without unnecessary content being generated, for
102 example.
103 Fixed path information for Zope.
104 Added WSGI support.
105 Verified Twisted 1.3.0 support with Python 2.3.3.
106
107 New in WebStack 0.7 (Changes since WebStack 0.6)
108 ------------------------------------------------
109
110 Fixed path information semantics.
111 Fixed file upload semantics.
112 Fixed content type handling for Unicode output and for interpreting request
113 body fields/parameters (although some improvement remains).
114 Added a method to discover the chosen response stream encoding.
115 Fixed field/parameter retrieval so that path and body fields are distinct,
116 regardless of the framework employed.
117 Added a method to get a combination of path and body fields (suggested by
118 Jacob Smullyan).
119 Introduced Zope 2 support.
120 Improved Jython/Java Servlet API support (although a special PyServlet class
121 must now be used, and certain libraries must be deployed with applications).
122 Introduced authentication/authorisation support for Jython/Java Servlet API.
123 Session support has been added (except for Webware 0.8.1).
124 Alternative cookie support for mod_python has been added.
125 Cookie support now supports encoded Unicode sequences for names and values.
126
127 New in WebStack 0.6 (Changes since WebStack 0.5)
128 ------------------------------------------------
129
130 Introduced Jython/Java Servlet API support.
131 Minor fixes to example applications and to BaseHTTPRequestHandler.
132
133 New in WebStack 0.5 (Changes since WebStack 0.4)
134 ------------------------------------------------
135
136 Changed request body fields/parameters so that they are now represented
137 using Unicode objects rather than plain strings.
138 Introduced better support for Unicode in response streams.
139
140 New in WebStack 0.4 (Changes since WebStack 0.3)
141 ------------------------------------------------
142
143 Added application definition of user identity, permitting alternative
144 authentication mechanisms.
145 Improved BaseHTTPRequestHandler and mod_python reliability around fields
146 from request bodies.
147 Provided stream and environment parameterisation in the CGI adapter.
148 Added LoginRedirect and Login examples.
149 Added get_path_without_query and fixed get_path behaviour.
150
151 New in WebStack 0.3 (Changes since WebStack 0.2)
152 ------------------------------------------------
153
154 Added better header support for Webware (suggested by Ian Bicking).
155 Introduced CGI and Java Servlet support (the latter is currently
156 broken/unfinished).
157 Introduced support for cookies.
158
159 Future Work
160 -----------
161
162 (Essential)
163
164 JythonServlet libraries need to be configured using sys.add_package when
165 these do not feature in the compiled-in list. Adding such configuration to
166 the handler may be most appropriate (since the web.xml file can be too
167 arcane), but this needs testing.
168
169 (Important)
170
171 Things to consider for future releases: improved cookie support, redirects,
172 access to shared resources and much better documentation.
173
174 Field access needs testing, especially for anything using the
175 cgi.FieldStorage class, and the way file uploads are exposed should be
176 reviewed (currently the meta-data is not exposed). The acquisition of fields
177 from specific sources should be tested with different request methods - some
178 frameworks provide path fields in the body fields dictionary, others (eg.
179 Zope) change the fields exposed depending on request method.
180
181 Interpretation of path field encodings needs to be verified. Currently,
182 stray path fields are handled (eg. in WebStack.Helpers.Request) as being
183 ISO-8859-1, but it might be the case that some such fields might be
184 submitted as UTF-8.
185
186 Cookie objects need defining strictly, especially since the standard library
187 Cookie object behaves differently to mod_python (and possibly Webware)
188 Cookie objects. Moreover, the set_cookie_value method needs to provide
189 access to the usual cookie parameters as supported by the frameworks. The
190 standard library Cookie module has issues with Unicode cookie names (and
191 possibly values) - this is worked around, but it would be best to resolve
192 this comprehensively.
193
194 UTF-16 (and possibly other encodings) causes problems with HTML form data
195 sent in POST requests using the application/x-www-form-urlencoded content
196 type. This should be reviewed at a later date when proper standardisation
197 has taken place.
198
199 Session support, especially through WebStack.Helpers.Session, should be
200 reviewed and be made compatible with non-cookie mechanisms.
201
202 HeaderValue objects should be employed more extensively. Thus, the header
203 access methods may need to change their behaviour slightly.
204
205 Investigate the nicer functions in the cgi module, discarding the "magic"
206 stuff like FieldStorage.
207
208 WSGI support could demand that a special "end of headers" method be
209 introduced into WebStack, thus making response output more efficient (and
210 probably also for other frameworks, too).
211
212 The algorithm employed in the WebStack.Helpers.Auth.get_token function
213 should be reviewed and improved for better security.
214
215 Investigate proper support for HEAD, OPTIONS and other request methods.
216
217 Consider packages for different operating systems.
218
219 (Completed/rejected)
220
221 The location of deployed applications in the filesystem should be exposed to
222 those applications. (This is actually available in the __file__ module
223 variable.)
224
225 Path information should be consistent across all frameworks, and the "path
226 info" value should be meaningful. (This should now be correct.)
227
228 Release Procedures
229 ------------------
230
231 Update the WebStack/__init__.py __version__ attribute.
232 Change the version number and package filename/directory in the documentation.
233 Change code examples in the documentation if appropriate.
234 Update the release notes (see above).
235 Check the setup.py file and ensure that all package directories are mentioned.
236 Check the release information in the PKG-INFO file and in the package
237 changelog (and other files).
238 Tag, export.
239 Generate the PyServlet classes.
240 Generate the API documentation.
241 Remove generated .pyc files: rm `find . -name "*.pyc"`
242 Archive, upload.
243 Upload the introductory documentation.
244 Update PyPI, PythonInfo Wiki, Vaults of Parnassus entries.
245
246 Generating the API Documentation
247 --------------------------------
248
249 In order to prepare the API documentation, it is necessary to generate some
250 Web pages from the Python source code. For this, the epydoc application must
251 be available on your system. Then, inside the WebStack directory, run the
252 apidocs.sh tool script as follows:
253
254 ./tools/apidocs.sh
255
256 Some warnings may be generated by the script, but the result should be a new
257 apidocs directory within the WebStack directory.