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 0.3.3
40 libxml2 Tested with 2.6.17
41 libxslt Tested with 1.1.12
42
43 The example Web applications require WebStack (release 1.1.2 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 * Changed the preparation of templates to produce rule-based output
50 stylesheets, thus permitting recursive templates. This requires an extra
51 expr-prefix annotation to be used in certain kinds of templates.
52 * Added a recursive template example application.
53 * Changed fragment production to use original template documents instead of
54 output stylesheets.
55 * Changed the in_page_resources attribute to provide the output identifier,
56 thus changing the prepare_fragment method in Web resources so that only
57 the fragment identifier needs to be supplied.
58 * Added the XSLForms.Resources.WebResources.prepare_resources method for the
59 preparation of initialiser and output stylesheets before an application is
60 run.
61 * Changed selectors to not automatically create elements in the form data
62 document unless requested to do so. Introduced a Form.get_selector
63 method in XSLForms.Fields.
64 * Introduced dynamic parameter evaluation for multiple-choice fields in
65 order to support sources of multiple-choice values which reside in the
66 form data document itself.
67 * Added the FixNamespace.xsl stylesheet to correct documents saved by HTML
68 editors which strip namespace prefixes.
69 * Fixed filesystem encoding issues in the Candidate example; fixed language
70 preference access in the Configurator and VerySimple examples.
71 * Changed the BaseHTTPRequestHandler version of the Candidate example to
72 store data in a subdirectory of the current working directory, thus
73 allowing the demonstration application to work after package installation.
74
75 New in XSLTools 0.3.1 (Changes since XSLTools 0.3)
76 --------------------------------------------------
77
78 * Fixed copyright and licensing information.
79
80 New in XSLTools 0.3 (Changes since XSLTools 0.2)
81 ------------------------------------------------
82
83 * Introduced copying of multiple-choice value element contents so that
84 option element labels can differ from the underlying values.
85 * Added internationalisation support, providing the template:i18n annotation
86 and the template:i18n extension function.
87 * Updated the documentation to cover the above new features.
88 * Fixed non-GET/POST request method handling in WebResources.
89 * Added the xslform_preparemacro.py script.
90 * Added an experimental template:range extension function.
91
92 New in XSLTools 0.2 (Changes since XSLTools 0.1)
93 ------------------------------------------------
94
95 * Made a new XSLTools package and moved XSLOutput into it.
96 * Improved serialisation of transformation results so that output options
97 are observed (in some cases, at least).
98 * Fixed stylesheet and reference document paths so that libxslt should not
99 now become confused by ambiguous relative paths.
100 * Added expression parameters to XSLOutput.Processor so that in-document
101 data can be used to, for example, initialise multiple-choice field values.
102 * Added input/initialiser support so that input documents can be tidied or
103 initialised using information from the template.
104 * Added template:init for use with template:element in XSLForms to control
105 element initialisation where necessary.
106 * Added special high-level "macro" attributes (eg. template:attribute-field)
107 which should make templates easier to write and maintain.
108 * Added template:if to XSLForms, providing conditional output of annotated
109 elements.
110 * Added set_document to XSLForms.Fields.Form.
111 * Added prepare_parameters to the XSLFormsResource class in the
112 XSLForms.Resources.WebResources module.
113 * Added element-path, url-encode and choice XSLForms extension functions.
114 * Improved Unicode support in the XSLForms extension functions.
115 * Changed in-page requests to contain proper POST data.
116 * Fixed checkbox and radiobutton value detection in XSLForms.js.
117 * Updated the code to work with WebStack 1.0 changes and adopted the
118 new-style WebStack demonstration mechanism.
119 * Added XMLCalendar and XMLTable (to the XSLTools package).
120 * Added a dictionary (or word lookup) example application.
121 * Added a job candidate profile (or CV editor) example application.
122 * Added a template attribute reference and an XSLFormsResource guide to the
123 documentation.
124 * Added Debian package support (specifically Ubuntu package support).
125 * Added missing COPYING.txt file.
126 * Renamed the scripts to avoid naming issues in system-wide installations.
127 * Added a PyQt example based on the system configurator example, with the
128 form prepared in Qt Designer. This example runs in PyQt and in a Web
129 environment without any changes to the application code. In-page updates
130 are currently not implemented in the Web version, however.
131
132 Notes on In-Page Update Functionality
133 -------------------------------------
134
135 Special note #1: Konqueror seems in certain cases to remember replaced form
136 content (when replaceChild is used to replace regions of the page which
137 include form elements). This causes the browser to believe that more form
138 fields exist on the page than actually do so, and subsequent form submissions
139 thus include the values of such removed fields. A special hack is in place to
140 disable form fields by changing their names, thus causing Konqueror to not
141 associate such fields with the real, active fields; this hack does not seem to
142 cause problems for Mozilla. This needs some investigation to determine in
143 exactly which circumstances the problem arises.
144
145 Special note #2: Konqueror also seems to crash if asked to find elements using
146 an empty 'id' attribute string. This needs some investigation to see if it
147 really is the getElementById call that causes the crash.
148
149 Special note #3: Konqueror's XMLHttpRequest seems to append null characters to
150 the end of field values. Attempting to prune them before the request is sent
151 fails with a function like the following:
152
153 function fixValue(fieldValue) {
154 if (fieldValue.length == 0) {
155 return fieldValue;
156 } else if (fieldValue[fieldValue.length - 1] == '\0') {
157 return fieldValue.substr(0, fieldValue.length - 1);
158 } else {
159 return fieldValue;
160 }
161 }
162
163 This may be because it is the entire message that is terminated with the null
164 character, and that this happens only upon sending the message. Consequently,
165 some frameworks (notably mod_python) do not support in-page functionality when
166 used from Konqueror.
167
168 Various browsers (eg. Mozilla/Firefox, Konqueror) will not allow the
169 XMLHttpRequest in-page updates to function unless the URL used in the
170 requestUpdate JavaScript function is compatible with the URL at which the
171 browser finds the application. Currently, relative URLs are in use to avoid
172 this issue of compatibility, but should an absolute URL be deduced using the
173 WebStack API and then used, it may be possible that the values returned by
174 that API do not match the actual addresses entered into the address bar of the
175 browser.
176
177 To check the behaviour of the applications, it is possible to view the
178 document source of the pages served by applications and to verify that the
179 URLs mentioned in the JavaScript function calls (to 'requestUpdate') either be
180 a relative link or involve a URL similar to that which appears in the
181 browser's address bar. In some environments, the use of 'localhost' addresses
182 often confuses the browser and server; one workaround is to use real host
183 names or addresses instead of 'localhost'.
184
185 Choosing an element-path:
186
187 When specifying the "context" of the in-page update, one must imagine which
188 element the template fragment should operate within. If the template:id
189 attribute marks a particular section, then the element-path should be a path
190 to the applicable context element for that section in the complete template
191 document. Note that if a template:element attribute appears on the same
192 element as the template:id attribute then the element-path should refer to the
193 element specified in the template:element attribute.
194
195 Choosing where to put template:attribute, template:id and id:
196
197 When specifying the extent of a template fragment, one must be sure not to put
198 the template:id attribute on the same element as a template:attribute
199 annotation; otherwise, the generated code will be improperly extracted as a
200 fragment producing two versions of the element - one for when the specified
201 attribute is present, and one for when it is not present. Generally,
202 template:id and id can be placed on the same node, however.
203
204 Stable element ordering and element-path:
205
206 Within the element-path, the numbering of the elements will start at 1.
207 Therefore it is vital to choose a region of the form data structure with the
208 element-path which is isolated from surrounding elements whose positions would
209 otherwise be dependent on a stable ordering of elements, and whose processing
210 would be disrupted if some new elements suddenly appeared claiming the same
211 positions in the document. For example:
212
213 <item value=""> .../item$1/value
214 <type value=""/> .../item$1/type$1/value
215 <comment value=""/> .../item$1/comment$2/value
216 </item>
217
218 In-page update...
219
220 <comment value=""/> .../item$1/comment$1/value
221
222 Notes on XSL
223 ------------
224
225 libxslt seems to be quite liberal on the definition of runtime parameters, in
226 that there is no apparent need to explicitly declare the corresponding global
227 variables in stylesheets. Whilst this is nice, we may eventually need to
228 detect such variables and add them in the preparation process.
229
230 Release Procedures
231 ------------------
232
233 Update the XSLTools/__init__.py and XSLForms/__init__.py __version__
234 attributes.
235 Change the version number and package filename/directory in the documentation.
236 Change code examples in the documentation if appropriate.
237 Update the release notes (see above).
238 Check the setup.py file and ensure that all package directories are mentioned.
239 Check the release information in the PKG-INFO file and in the package
240 changelog (and other files).
241 Tag, export.
242 Generate the example resources.
243 Generate the API documentation.
244 Remove generated .pyc files: rm `find . -name "*.pyc"`
245 Archive, upload.
246 Upload the introductory documentation.
247 Update PyPI, PythonInfo Wiki, Vaults of Parnassus entries.
248
249 Generating the Example Resources
250 --------------------------------
251
252 In order to prepare the example resources, the prepare_demo.py script must be
253 run as follows:
254
255 python tools/prepare_demo.py
256
257 This will ensure that all initialiser and output stylesheets are created and
258 are thus installed by packages.
259
260 Generating the API Documentation
261 --------------------------------
262
263 In order to prepare the API documentation, it is necessary to generate some
264 Web pages from the Python source code. For this, the epydoc application must
265 be available on your system. Then, inside the distribution directory, run the
266 apidocs.sh tool script as follows:
267
268 ./tools/apidocs.sh
269
270 Some warnings may be generated by the script, but the result should be a new
271 apidocs directory within the distribution directory.
272
273 Making Packages
274 ---------------
275
276 To make Debian-based packages:
277
278 1. Create new package directories under packages if necessary.
279 2. Make a symbolic link in the distribution's root directory to keep the
280 Debian tools happy:
281
282 ln -s packages/ubuntu-hoary/python2.4-xsltools/debian/
283
284 3. Run the package builder:
285
286 dpkg-buildpackage -rfakeroot
287
288 4. Locate and tidy up the packages in the parent directory of the
289 distribution's root directory.
