1 Introduction
2 ------------
3
4 XSLTools is a collection of modules and packages facilitating the development
5 of applications based on XML, XSL stylesheets and transformations, notably Web
6 applications involving complicated Web forms potentially consisting of
7 editable hierarchical structures and potentially involving "live" or "in-page"
8 dynamic updates to portions of those Web forms.
9
10 Quick Start
11 -----------
12
13 Try running the demo:
14
15 python tools/demo.py
16
17 An introductory guide to creating applications can be found in the docs
18 directory - see docs/index.html for the start page.
19
20 Contact, Copyright and Licence Information
21 ------------------------------------------
22
23 The current Web page for XSLTools at the time of release is:
24
25 http://www.boddie.org.uk/python/XSLTools.html
26
27 Copyright and licence information can be found in the docs directory - see
28 docs/COPYING.txt, docs/LICENCE.txt and docs/LICENCE-Sarissa.txt for more
29 information.
30
31 Dependencies
32 ------------
33
34 XSLTools has the following basic dependencies:
35
36 Package Release Information
37 ------- -------------------
38
39 libxml2dom 0.2.1
40 libxml2 Tested with 2.6.17
41 libxslt Tested with 1.1.12
42
43 The example Web applications require WebStack (release 1.0 or later).
44
45 New in XSLTools 0.2 (Changes since XSLTools 0.1)
46 ------------------------------------------------
47
48 Made a new XSLTools package and moved XSLOutput into it.
49 Added XMLCalendar and XMLTable (to the XSLTools package).
50 Changed in-page requests to contain proper POST data.
51 Added Debian package support.
52 Added missing COPYING.txt file.
53 Renamed the scripts to avoid naming issues in system-wide installations.
54 Added template:if to XSLForms.
55 Updated the code to work with WebStack 1.0 changes.
56
57 Notes on In-Page Update Functionality
58 -------------------------------------
59
60 Special note #1: Konqueror seems in certain cases to remember replaced form
61 content (when replaceChild is used to replace regions of the page which
62 include form elements). This causes the browser to believe that more form
63 fields exist on the page than actually do so, and subsequent form submissions
64 thus include the values of such removed fields. A special hack is in place to
65 disable form fields by changing their names, thus causing Konqueror to not
66 associate such fields with the real, active fields; this hack does not seem to
67 cause problems for Mozilla. This needs some investigation to determine in
68 exactly which circumstances the problem arises.
69
70 Special note #2: Konqueror also seems to crash if asked to find elements using
71 an empty 'id' attribute string. This needs some investigation to see if it
72 really is the getElementById call that causes the crash.
73
74 Special note #3: Konqueror's XMLHttpRequest seems to append null characters to
75 the end of field values. Attempting to prune them before the request is sent
76 fails with a function like the following:
77
78 function fixValue(fieldValue) {
79 if (fieldValue.length == 0) {
80 return fieldValue;
81 } else if (fieldValue[fieldValue.length - 1] == '\0') {
82 return fieldValue.substr(0, fieldValue.length - 1);
83 } else {
84 return fieldValue;
85 }
86 }
87
88 This may be because it is the entire message that is terminated with the null
89 character, and that this happens only upon sending the message. Consequently,
90 some frameworks (notably mod_python) do not support in-page functionality when
91 used from Konqueror.
92
93 Various browsers (eg. Mozilla/Firefox, Konqueror) will not allow the
94 XMLHttpRequest in-page updates to function unless the URL used in the
95 requestUpdate JavaScript function is compatible with the URL at which the
96 browser finds the application. Currently, relative URLs are in use to avoid
97 this issue of compatibility, but should an absolute URL be deduced using the
98 WebStack API and then used, it may be possible that the values returned by
99 that API do not match the actual addresses entered into the address bar of the
100 browser.
101
102 To check the behaviour of the applications, it is possible to view the
103 document source of the pages served by applications and to verify that the
104 URLs mentioned in the JavaScript function calls (to 'requestUpdate') either be
105 a relative link or involve a URL similar to that which appears in the
106 browser's address bar. In some environments, the use of 'localhost' addresses
107 often confuses the browser and server; one workaround is to use real host
108 names or addresses instead of 'localhost'.
109
110 Choosing an element-path:
111
112 When specifying the "context" of the in-page update, one must imagine which
113 element the template fragment should operate within. If the template:id
114 attribute marks a particular section, then the element-path should be a path
115 to the applicable context element for that section in the complete template
116 document. Note that if a template:element attribute appears on the same
117 element as the template:id attribute then the element-path should refer to the
118 element specified in the template:element attribute.
119
120 Choosing where to put template:attribute, template:id and id:
121
122 When specifying the extent of a template fragment, one must be sure not to put
123 the template:id attribute on the same element as a template:attribute
124 annotation; otherwise, the generated code will be improperly extracted as a
125 fragment producing two versions of the element - one for when the specified
126 attribute is present, and one for when it is not present. Generally,
127 template:id and id can be placed on the same node, however.
128
129 Stable element ordering and element-path:
130
131 Within the element-path, the numbering of the elements will start at 1.
132 Therefore it is vital to choose a region of the form data structure with the
133 element-path which is isolated from surrounding elements whose positions would
134 otherwise be dependent on a stable ordering of elements, and whose processing
135 would be disrupted if some new elements suddenly appeared claiming the same
136 positions in the document. For example:
137
138 <item value=""> .../item$1/value
139 <type value=""/> .../item$1/type$1/value
140 <comment value=""/> .../item$1/comment$2/value
141 </item>
142
143 In-page update...
144
145 <comment value=""/> .../item$1/comment$1/value
146
147 Notes on XSL
148 ------------
149
150 libxslt seems to be quite liberal on the definition of runtime parameters, in
151 that there is no apparent need to explicitly declare the corresponding global
152 variables in stylesheets. Whilst this is nice, we may eventually need to
153 detect such variables and add them in the preparation process.
154
155 Release Procedures
156 ------------------
157
158 Update the XSLTools/__init__.py and XSLForms/__init__.py __version__
159 attributes.
160 Change the version number and package filename/directory in the documentation.
161 Change code examples in the documentation if appropriate.
162 Update the release notes (see above).
163 Check the setup.py file and ensure that all package directories are mentioned.
164 Check the release information in the PKG-INFO file and in the package
165 changelog (and other files).
166 Tag, export.
167 Generate the API documentation.
168 Remove generated .pyc files: rm `find . -name "*.pyc"`
169 Archive, upload.
170 Upload the introductory documentation.
171 Update PyPI, PythonInfo Wiki, Vaults of Parnassus entries.
172
173 Generating the API Documentation
174 --------------------------------
175
176 In order to prepare the API documentation, it is necessary to generate some
177 Web pages from the Python source code. For this, the epydoc application must
178 be available on your system. Then, inside the XSLTools directory, run the
179 apidocs.sh tool script as follows:
180
181 ./tools/apidocs.sh
182
183 Some warnings may be generated by the script, but the result should be a new
184 apidocs directory within the XSLTools directory.
185
186 Making Packages
187 ---------------
188
189 To make Debian packages:
190
191 1. Create new package directories under packages/debian if necessary.
192 2. Make a symbolic link in the distribution's root directory to keep the
193 Debian tools happy:
194
195 ln -s packages/debian/python2.4-xsltools/debian/
196
197 3. Run the package builder:
198
199 dpkg-buildpackage -rfakeroot
200
201 4. Locate and tidy up the packages in the parent directory of the
202 distribution's root directory.