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