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 Added support for the repeated retrieval of sessions from the same WebStack
62 session store, avoiding deadlocks.
63 Fixed the calendar example, making it perform a proper function.
64 Added the notion of processed virtual path info - the part of the original
65 path info not represented in the current virtual path info (prompted by a
66 different suggestion from Scott Robinson).
67 Changed the ResourceMap.MapResource class to provide the empty string as the
68 resource name where the virtual path info is only one component in length.
69
70 New in WebStack 0.10 (Changes since WebStack 0.9)
71 -------------------------------------------------
72
73 Changes to make the tools/demo.py script work on Windows (and other) platforms
74 (suggested by Jim Madsen).
75 Fixed end of header newlines for CGI (suggested by Matt Harrison).
76 Minor documentation fixes and improvements, adding information on AOLserver in
77 the CGI and Webware notes.
78 Changed the mod_python server name method to use the server object rather than
79 the connection object.
80 Added a parameter to the ResourceMap.MapResource class to permit automatic
81 redirects into resource hierarchies when no trailing "/" was given in the URL;
82 changed the updated virtual path info so that empty values may be set (the
83 guarantee that "/" will always appear no longer applies).
84 Fixed virtual path info retrieval when the value is an empty string.
85
86 New in WebStack 0.9 (Changes since WebStack 0.8)
87 ------------------------------------------------
88
89 Standardised error handling in the adapters so that tracebacks can be
90 suppressed and an internal server error condition raised.
91 Added overriding of path info in transactions.
92 Added a ResourceMap resource for dispatching to different resources
93 according to path components.
94 Standardised deployment for some frameworks (see docs/deploying.html).
95 Introductory documentation in XHTML format.
96 Added server name and port methods to the transaction.
97 Added a simple demonstration application, incorporating many of the examples
98 and launched under a single script.
99 Fixed mod_python native sessions.
100 Fixed Zope request stream access.
101 WebStack is now licensed under the LGPL - see docs/COPYING.txt for details.
102
103 New in WebStack 0.8 (Changes since WebStack 0.7)
104 ------------------------------------------------
105
106 Added a standard exception, EndOfResponse, which can be used to immediately
107 stop the processing/production of a response; this is useful when resources
108 need to issue a redirect without unnecessary content being generated, for
109 example.
110 Fixed path information for Zope.
111 Added WSGI support.
112 Verified Twisted 1.3.0 support with Python 2.3.3.
113
114 New in WebStack 0.7 (Changes since WebStack 0.6)
115 ------------------------------------------------
116
117 Fixed path information semantics.
118 Fixed file upload semantics.
119 Fixed content type handling for Unicode output and for interpreting request
120 body fields/parameters (although some improvement remains).
121 Added a method to discover the chosen response stream encoding.
122 Fixed field/parameter retrieval so that path and body fields are distinct,
123 regardless of the framework employed.
124 Added a method to get a combination of path and body fields (suggested by
125 Jacob Smullyan).
126 Introduced Zope 2 support.
127 Improved Jython/Java Servlet API support (although a special PyServlet class
128 must now be used, and certain libraries must be deployed with applications).
129 Introduced authentication/authorisation support for Jython/Java Servlet API.
130 Session support has been added (except for Webware 0.8.1).
131 Alternative cookie support for mod_python has been added.
132 Cookie support now supports encoded Unicode sequences for names and values.
133
134 New in WebStack 0.6 (Changes since WebStack 0.5)
135 ------------------------------------------------
136
137 Introduced Jython/Java Servlet API support.
138 Minor fixes to example applications and to BaseHTTPRequestHandler.
139
140 New in WebStack 0.5 (Changes since WebStack 0.4)
141 ------------------------------------------------
142
143 Changed request body fields/parameters so that they are now represented
144 using Unicode objects rather than plain strings.
145 Introduced better support for Unicode in response streams.
146
147 New in WebStack 0.4 (Changes since WebStack 0.3)
148 ------------------------------------------------
149
150 Added application definition of user identity, permitting alternative
151 authentication mechanisms.
152 Improved BaseHTTPRequestHandler and mod_python reliability around fields
153 from request bodies.
154 Provided stream and environment parameterisation in the CGI adapter.
155 Added LoginRedirect and Login examples.
156 Added get_path_without_query and fixed get_path behaviour.
157
158 New in WebStack 0.3 (Changes since WebStack 0.2)
159 ------------------------------------------------
160
161 Added better header support for Webware (suggested by Ian Bicking).
162 Introduced CGI and Java Servlet support (the latter is currently
163 broken/unfinished).
164 Introduced support for cookies.
165
166 Future Work
167 -----------
168
169 (Essential)
170
171 JythonServlet libraries need to be configured using sys.add_package when
172 these do not feature in the compiled-in list. Adding such configuration to
173 the handler may be most appropriate (since the web.xml file can be too
174 arcane), but this needs testing.
175
176 (Important)
177
178 Things to consider for future releases: improved cookie support, redirects,
179 access to shared resources and much better documentation.
180
181 Field access needs testing, especially for anything using the
182 cgi.FieldStorage class, and the way file uploads are exposed should be
183 reviewed (currently the meta-data is not exposed). The acquisition of fields
184 from specific sources should be tested with different request methods - some
185 frameworks provide path fields in the body fields dictionary, others (eg.
186 Zope) change the fields exposed depending on request method.
187
188 Interpretation of path field encodings needs to be verified. Currently,
189 stray path fields are handled (eg. in WebStack.Helpers.Request) as being
190 ISO-8859-1, but it might be the case that some such fields might be
191 submitted as UTF-8.
192
193 Cookie objects need defining strictly, especially since the standard library
194 Cookie object behaves differently to mod_python (and possibly Webware)
195 Cookie objects. Moreover, the set_cookie_value method needs to provide
196 access to the usual cookie parameters as supported by the frameworks. The
197 standard library Cookie module has issues with Unicode cookie names (and
198 possibly values) - this is worked around, but it would be best to resolve
199 this comprehensively.
200
201 UTF-16 (and possibly other encodings) causes problems with HTML form data
202 sent in POST requests using the application/x-www-form-urlencoded content
203 type. This should be reviewed at a later date when proper standardisation
204 has taken place.
205
206 Session support, especially through WebStack.Helpers.Session, should be
207 reviewed and be made compatible with non-cookie mechanisms.
208
209 HeaderValue objects should be employed more extensively. Thus, the header
210 access methods may need to change their behaviour slightly.
211
212 Investigate the nicer functions in the cgi module, discarding the "magic"
213 stuff like FieldStorage.
214
215 WSGI support could demand that a special "end of headers" method be
216 introduced into WebStack, thus making response output more efficient (and
217 probably also for other frameworks, too).
218
219 The algorithm employed in the WebStack.Helpers.Auth.get_token function
220 should be reviewed and improved for better security.
221
222 Investigate proper support for HEAD, OPTIONS and other request methods.
223
224 Consider packages for different operating systems.
225
226 (Completed/rejected)
227
228 The location of deployed applications in the filesystem should be exposed to
229 those applications. (This is actually available in the __file__ module
230 variable.)
231
232 Path information should be consistent across all frameworks, and the "path
233 info" value should be meaningful. (This should now be correct.)
234
235 Release Procedures
236 ------------------
237
238 Update the WebStack/__init__.py __version__ attribute.
239 Change the version number and package filename/directory in the documentation.
240 Change code examples in the documentation if appropriate.
241 Update the release notes (see above).
242 Check the setup.py file and ensure that all package directories are mentioned.
243 Check the release information in the PKG-INFO file and in the package
244 changelog (and other files).
245 Tag, export.
246 Generate the PyServlet classes.
247 Generate the API documentation.
248 Remove generated .pyc files: rm `find . -name "*.pyc"`
249 Archive, upload.
250 Upload the introductory documentation.
251 Update PyPI, PythonInfo Wiki, Vaults of Parnassus entries.
252
253 Generating the API Documentation
254 --------------------------------
255
256 In order to prepare the API documentation, it is necessary to generate some
257 Web pages from the Python source code. For this, the epydoc application must
258 be available on your system. Then, inside the WebStack directory, run the
259 apidocs.sh tool script as follows:
260
261 ./tools/apidocs.sh
262
263 Some warnings may be generated by the script, but the result should be a new
264 apidocs directory within the WebStack directory.
