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