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 0.3.2
40 libxml2 Tested with 2.6.17
41 libxslt Tested with 1.1.12
42
43 The example Web applications require WebStack (release 1.1.1 or later).
44 The example PyQt applications have been tested with PyQt 3.15.
45
46 New in XSLTools 0.4 (Changes since XSLTools 0.3.1)
47 --------------------------------------------------
48
49 * Introduced dynamic parameter evaluation for multiple-choice fields in
50 order to support sources of multiple-choice values which reside in the
51 form data document itself.
52
53 New in XSLTools 0.3.1 (Changes since XSLTools 0.3)
54 --------------------------------------------------
55
56 * Fixed copyright and licensing information.
57
58 New in XSLTools 0.3 (Changes since XSLTools 0.2)
59 ------------------------------------------------
60
61 * Introduced copying of multiple-choice value element contents so that
62 option element labels can differ from the underlying values.
63 * Added internationalisation support, providing the template:i18n annotation
64 and the template:i18n extension function.
65 * Updated the documentation to cover the above new features.
66 * Fixed non-GET/POST request method handling in WebResources.
67 * Added the xslform_preparemacro.py script.
68 * Added an experimental template:range extension function.
69
70 New in XSLTools 0.2 (Changes since XSLTools 0.1)
71 ------------------------------------------------
72
73 * Made a new XSLTools package and moved XSLOutput into it.
74 * Improved serialisation of transformation results so that output options
75 are observed (in some cases, at least).
76 * Fixed stylesheet and reference document paths so that libxslt should not
77 now become confused by ambiguous relative paths.
78 * Added expression parameters to XSLOutput.Processor so that in-document
79 data can be used to, for example, initialise multiple-choice field values.
80 * Added input/initialiser support so that input documents can be tidied or
81 initialised using information from the template.
82 * Added template:init for use with template:element in XSLForms to control
83 element initialisation where necessary.
84 * Added special high-level "macro" attributes (eg. template:attribute-field)
85 which should make templates easier to write and maintain.
86 * Added template:if to XSLForms, providing conditional output of annotated
87 elements.
88 * Added set_document to XSLForms.Fields.Form.
89 * Added prepare_parameters to the XSLFormsResource class in the
90 XSLForms.Resources.WebResources module.
91 * Added element-path, url-encode and choice XSLForms extension functions.
92 * Improved Unicode support in the XSLForms extension functions.
93 * Changed in-page requests to contain proper POST data.
94 * Fixed checkbox and radiobutton value detection in XSLForms.js.
95 * Updated the code to work with WebStack 1.0 changes and adopted the
96 new-style WebStack demonstration mechanism.
97 * Added XMLCalendar and XMLTable (to the XSLTools package).
98 * Added a dictionary (or word lookup) example application.
99 * Added a job candidate profile (or CV editor) example application.
100 * Added a template attribute reference and an XSLFormsResource guide to the
101 documentation.
102 * Added Debian package support (specifically Ubuntu package support).
103 * Added missing COPYING.txt file.
104 * Renamed the scripts to avoid naming issues in system-wide installations.
105 * Added a PyQt example based on the system configurator example, with the
106 form prepared in Qt Designer. This example runs in PyQt and in a Web
107 environment without any changes to the application code. In-page updates
108 are currently not implemented in the Web version, however.
109
110 Notes on In-Page Update Functionality
111 -------------------------------------
112
113 Special note #1: Konqueror seems in certain cases to remember replaced form
114 content (when replaceChild is used to replace regions of the page which
115 include form elements). This causes the browser to believe that more form
116 fields exist on the page than actually do so, and subsequent form submissions
117 thus include the values of such removed fields. A special hack is in place to
118 disable form fields by changing their names, thus causing Konqueror to not
119 associate such fields with the real, active fields; this hack does not seem to
120 cause problems for Mozilla. This needs some investigation to determine in
121 exactly which circumstances the problem arises.
122
123 Special note #2: Konqueror also seems to crash if asked to find elements using
124 an empty 'id' attribute string. This needs some investigation to see if it
125 really is the getElementById call that causes the crash.
126
127 Special note #3: Konqueror's XMLHttpRequest seems to append null characters to
128 the end of field values. Attempting to prune them before the request is sent
129 fails with a function like the following:
130
131 function fixValue(fieldValue) {
132 if (fieldValue.length == 0) {
133 return fieldValue;
134 } else if (fieldValue[fieldValue.length - 1] == '\0') {
135 return fieldValue.substr(0, fieldValue.length - 1);
136 } else {
137 return fieldValue;
138 }
139 }
140
141 This may be because it is the entire message that is terminated with the null
142 character, and that this happens only upon sending the message. Consequently,
143 some frameworks (notably mod_python) do not support in-page functionality when
144 used from Konqueror.
145
146 Various browsers (eg. Mozilla/Firefox, Konqueror) will not allow the
147 XMLHttpRequest in-page updates to function unless the URL used in the
148 requestUpdate JavaScript function is compatible with the URL at which the
149 browser finds the application. Currently, relative URLs are in use to avoid
150 this issue of compatibility, but should an absolute URL be deduced using the
151 WebStack API and then used, it may be possible that the values returned by
152 that API do not match the actual addresses entered into the address bar of the
153 browser.
154
155 To check the behaviour of the applications, it is possible to view the
156 document source of the pages served by applications and to verify that the
157 URLs mentioned in the JavaScript function calls (to 'requestUpdate') either be
158 a relative link or involve a URL similar to that which appears in the
159 browser's address bar. In some environments, the use of 'localhost' addresses
160 often confuses the browser and server; one workaround is to use real host
161 names or addresses instead of 'localhost'.
162
163 Choosing an element-path:
164
165 When specifying the "context" of the in-page update, one must imagine which
166 element the template fragment should operate within. If the template:id
167 attribute marks a particular section, then the element-path should be a path
168 to the applicable context element for that section in the complete template
169 document. Note that if a template:element attribute appears on the same
170 element as the template:id attribute then the element-path should refer to the
171 element specified in the template:element attribute.
172
173 Choosing where to put template:attribute, template:id and id:
174
175 When specifying the extent of a template fragment, one must be sure not to put
176 the template:id attribute on the same element as a template:attribute
177 annotation; otherwise, the generated code will be improperly extracted as a
178 fragment producing two versions of the element - one for when the specified
179 attribute is present, and one for when it is not present. Generally,
180 template:id and id can be placed on the same node, however.
181
182 Stable element ordering and element-path:
183
184 Within the element-path, the numbering of the elements will start at 1.
185 Therefore it is vital to choose a region of the form data structure with the
186 element-path which is isolated from surrounding elements whose positions would
187 otherwise be dependent on a stable ordering of elements, and whose processing
188 would be disrupted if some new elements suddenly appeared claiming the same
189 positions in the document. For example:
190
191 <item value=""> .../item$1/value
192 <type value=""/> .../item$1/type$1/value
193 <comment value=""/> .../item$1/comment$2/value
194 </item>
195
196 In-page update...
197
198 <comment value=""/> .../item$1/comment$1/value
199
200 Notes on XSL
201 ------------
202
203 libxslt seems to be quite liberal on the definition of runtime parameters, in
204 that there is no apparent need to explicitly declare the corresponding global
205 variables in stylesheets. Whilst this is nice, we may eventually need to
206 detect such variables and add them in the preparation process.
207
208 Release Procedures
209 ------------------
210
211 Update the XSLTools/__init__.py and XSLForms/__init__.py __version__
212 attributes.
213 Change the version number and package filename/directory in the documentation.
214 Change code examples in the documentation if appropriate.
215 Update the release notes (see above).
216 Check the setup.py file and ensure that all package directories are mentioned.
217 Check the release information in the PKG-INFO file and in the package
218 changelog (and other files).
219 Tag, export.
220 Generate the API documentation.
221 Remove generated .pyc files: rm `find . -name "*.pyc"`
222 Archive, upload.
223 Upload the introductory documentation.
224 Update PyPI, PythonInfo Wiki, Vaults of Parnassus entries.
225
226 Generating the API Documentation
227 --------------------------------
228
229 In order to prepare the API documentation, it is necessary to generate some
230 Web pages from the Python source code. For this, the epydoc application must
231 be available on your system. Then, inside the distribution directory, run the
232 apidocs.sh tool script as follows:
233
234 ./tools/apidocs.sh
235
236 Some warnings may be generated by the script, but the result should be a new
237 apidocs directory within the distribution directory.
238
239 Making Packages
240 ---------------
241
242 To make Debian-based packages:
243
244 1. Create new package directories under packages if necessary.
245 2. Make a symbolic link in the distribution's root directory to keep the
246 Debian tools happy:
247
248 ln -s packages/ubuntu-hoary/python2.4-xsltools/debian/
249
250 3. Run the package builder:
251
252 dpkg-buildpackage -rfakeroot
253
254 4. Locate and tidy up the packages in the parent directory of the
255 distribution's root directory.