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/LICENCE.txt and docs/LICENCE-PyServlet.txt for more information.
30
31 Framework Support
32 -----------------
33
34 Currently, BaseHTTPRequestHandler (via BaseHTTPServer in the standard
35 library), CGI, Jython/Java Servlet API, mod_python, Twisted, Webware, WSGI
36 and Zope 2 are supported. Each framework has its own set of strengths and
37 weaknesses, but the idea is that deployment concerns can be considered
38 separately from the implementation of application functionality. Consult the
39 NOTES.txt files in each framework's subdirectory of the docs directory for
40 some notes on how applications may be run in each environment.
41
42 Tested Frameworks Release Information
43 ----------------- -------------------
44
45 BaseHTTPRequestHandler Python 2.2.2, Python 2.3.3, Python 2.4.1
46 CGI Apache 2.0.44, Apache 2.0.53, AOLserver 4.0.10
47 Jython/Java Servlet API Jython 2.1, Java JDK 1.3.1_02, Tomcat 4.1.27 (Servlet 2.3)
48 mod_python 3.0.3 (3.1.3 for framework cookie and session support)
49 Twisted 1.0.5, 1.3.0
50 Webware 0.8.1, CVS (2004-02-06)
51 WSGI run_with_cgi (PEP 333)
52 Zope 2.7.2-0, 2.8.0-final
53
54 New in WebStack 0.10 (Changes since WebStack 0.9)
55 -------------------------------------------------
56
57 Changes to make the tools/demo.py script work on Windows (and other) platforms
58 (suggested by Jim Madsen).
59 Minor documentation fixes and improvements, adding information on AOLserver in
60 the CGI and Webware notes.
61
62 New in WebStack 0.9 (Changes since WebStack 0.8)
63 ------------------------------------------------
64
65 Standardised error handling in the adapters so that tracebacks can be
66 suppressed and an internal server error condition raised.
67 Added overriding of path info in transactions.
68 Added a ResourceMap resource for dispatching to different resources
69 according to path components.
70 Standardised deployment for some frameworks (see docs/deploying.html).
71 Introductory documentation in XHTML format.
72 Added server name and port methods to the transaction.
73 Added a simple demonstration application, incorporating many of the examples
74 and launched under a single script.
75 Fixed mod_python native sessions.
76 Fixed Zope request stream access.
77 WebStack is now licensed under the LGPL - see docs/COPYING.txt for details.
78
79 New in WebStack 0.8 (Changes since WebStack 0.7)
80 ------------------------------------------------
81
82 Added a standard exception, EndOfResponse, which can be used to immediately
83 stop the processing/production of a response; this is useful when resources
84 need to issue a redirect without unnecessary content being generated, for
85 example.
86 Fixed path information for Zope.
87 Added WSGI support.
88 Verified Twisted 1.3.0 support with Python 2.3.3.
89
90 New in WebStack 0.7 (Changes since WebStack 0.6)
91 ------------------------------------------------
92
93 Fixed path information semantics.
94 Fixed file upload semantics.
95 Fixed content type handling for Unicode output and for interpreting request
96 body fields/parameters (although some improvement remains).
97 Added a method to discover the chosen response stream encoding.
98 Fixed field/parameter retrieval so that path and body fields are distinct,
99 regardless of the framework employed.
100 Added a method to get a combination of path and body fields (suggested by
101 Jacob Smullyan).
102 Introduced Zope 2 support.
103 Improved Jython/Java Servlet API support (although a special PyServlet class
104 must now be used, and certain libraries must be deployed with applications).
105 Introduced authentication/authorisation support for Jython/Java Servlet API.
106 Session support has been added (except for Webware 0.8.1).
107 Alternative cookie support for mod_python has been added.
108 Cookie support now supports encoded Unicode sequences for names and values.
109
110 New in WebStack 0.6 (Changes since WebStack 0.5)
111 ------------------------------------------------
112
113 Introduced Jython/Java Servlet API support.
114 Minor fixes to example applications and to BaseHTTPRequestHandler.
115
116 New in WebStack 0.5 (Changes since WebStack 0.4)
117 ------------------------------------------------
118
119 Changed request body fields/parameters so that they are now represented
120 using Unicode objects rather than plain strings.
121 Introduced better support for Unicode in response streams.
122
123 New in WebStack 0.4 (Changes since WebStack 0.3)
124 ------------------------------------------------
125
126 Added application definition of user identity, permitting alternative
127 authentication mechanisms.
128 Improved BaseHTTPRequestHandler and mod_python reliability around fields
129 from request bodies.
130 Provided stream and environment parameterisation in the CGI adapter.
131 Added LoginRedirect and Login examples.
132 Added get_path_without_query and fixed get_path behaviour.
133
134 New in WebStack 0.3 (Changes since WebStack 0.2)
135 ------------------------------------------------
136
137 Added better header support for Webware (suggested by Ian Bicking).
138 Introduced CGI and Java Servlet support (the latter is currently
139 broken/unfinished).
140 Introduced support for cookies.
141
142 Future Work
143 -----------
144
145 (Essential)
146
147 JythonServlet libraries need to be configured using sys.add_package when
148 these do not feature in the compiled-in list. Adding such configuration to
149 the handler may be most appropriate (since the web.xml file can be too
150 arcane), but this needs testing.
151
152 (Important)
153
154 Things to consider for future releases: improved cookie support, redirects,
155 access to shared resources and much better documentation.
156
157 Field access needs testing, especially for anything using the
158 cgi.FieldStorage class, and the way file uploads are exposed should be
159 reviewed (currently the meta-data is not exposed). The acquisition of fields
160 from specific sources should be tested with different request methods - some
161 frameworks provide path fields in the body fields dictionary, others (eg.
162 Zope) change the fields exposed depending on request method.
163
164 Interpretation of path field encodings needs to be verified. Currently,
165 stray path fields are handled (eg. in WebStack.Helpers.Request) as being
166 ISO-8859-1, but it might be the case that some such fields might be
167 submitted as UTF-8.
168
169 Cookie objects need defining strictly, especially since the standard library
170 Cookie object behaves differently to mod_python (and possibly Webware)
171 Cookie objects. Moreover, the set_cookie_value method needs to provide
172 access to the usual cookie parameters as supported by the frameworks. The
173 standard library Cookie module has issues with Unicode cookie names (and
174 possibly values) - this is worked around, but it would be best to resolve
175 this comprehensively.
176
177 UTF-16 (and possibly other encodings) causes problems with HTML form data
178 sent in POST requests using the application/x-www-form-urlencoded content
179 type. This should be reviewed at a later date when proper standardisation
180 has taken place.
181
182 Session support, especially through WebStack.Helpers.Session, should be
183 reviewed and be made compatible with non-cookie mechanisms.
184
185 HeaderValue objects should be employed more extensively. Thus, the header
186 access methods may need to change their behaviour slightly.
187
188 Investigate the nicer functions in the cgi module, discarding the "magic"
189 stuff like FieldStorage.
190
191 WSGI support could demand that a special "end of headers" method be
192 introduced into WebStack, thus making response output more efficient (and
193 probably also for other frameworks, too).
194
195 The algorithm employed in the WebStack.Helpers.Auth.get_token function
196 should be reviewed and improved for better security.
197
198 Investigate proper support for HEAD, OPTIONS and other request methods.
199
200 Consider packages for different operating systems.
201
202 (Completed/rejected)
203
204 The location of deployed applications in the filesystem should be exposed to
205 those applications. (This is actually available in the __file__ module
206 variable.)
207
208 Path information should be consistent across all frameworks, and the "path
209 info" value should be meaningful. (This should now be correct.)
210
211 Release Procedures
212 ------------------
213
214 Update the WebStack/__init__.py __version__ attribute.
215 Change the version number and package filename/directory in the documentation.
216 Change code examples in the documentation if appropriate.
217 Update the release notes (see above).
218 Check the setup.py file and ensure that all package directories are mentioned.
219 Tag, export.
220 Generate the PyServlet classes.
221 Generate the API documentation.
222 Remove generated .pyc files: rm `find . -name "*.pyc"`
223 Archive, upload.
224 Upload the introductory documentation.
225 Update PyPI, PythonInfo Wiki, Vaults of Parnassus entries.
226
227 Generating the API Documentation
228 --------------------------------
229
230 In order to prepare the API documentation, it is necessary to generate some
231 Web pages from the Python source code. For this, the epydoc application must
232 be available on your system. Then, inside the WebStack directory, run the
233 apidocs.sh tool script as follows:
234
235 ./tools/apidocs.sh
236
237 Some warnings may be generated by the script, but the result should be a new
238 apidocs directory within the WebStack directory.