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