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