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 0.2.4
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 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 the xslform_preparemacro.py script.
52
53 New in XSLTools 0.2 (Changes since XSLTools 0.1)
54 ------------------------------------------------
55
56 * Made a new XSLTools package and moved XSLOutput into it.
57 * Improved serialisation of transformation results so that output options
58 are observed (in some cases, at least).
59 * Fixed stylesheet and reference document paths so that libxslt should not
60 now become confused by ambiguous relative paths.
61 * Added expression parameters to XSLOutput.Processor so that in-document
62 data can be used to, for example, initialise multiple-choice field values.
63 * Added input/initialiser support so that input documents can be tidied or
64 initialised using information from the template.
65 * Added template:init for use with template:element in XSLForms to control
66 element initialisation where necessary.
67 * Added special high-level "macro" attributes (eg. template:attribute-field)
68 which should make templates easier to write and maintain.
69 * Added template:if to XSLForms, providing conditional output of annotated
70 elements.
71 * Added set_document to XSLForms.Fields.Form.
72 * Added prepare_parameters to the XSLFormsResource class in the
73 XSLForms.Resources.WebResources module.
74 * Added element-path, url-encode and choice XSLForms extension functions.
75 * Improved Unicode support in the XSLForms extension functions.
76 * Changed in-page requests to contain proper POST data.
77 * Fixed checkbox and radiobutton value detection in XSLForms.js.
78 * Updated the code to work with WebStack 1.0 changes and adopted the
79 new-style WebStack demonstration mechanism.
80 * Added XMLCalendar and XMLTable (to the XSLTools package).
81 * Added a dictionary (or word lookup) example application.
82 * Added a job candidate profile (or CV editor) example application.
83 * Added a template attribute reference and an XSLFormsResource guide to the
84 documentation.
85 * Added Debian package support (specifically Ubuntu package support).
86 * Added missing COPYING.txt file.
87 * Renamed the scripts to avoid naming issues in system-wide installations.
88 * Added a PyQt example based on the system configurator example, with the
89 form prepared in Qt Designer. This example runs in PyQt and in a Web
90 environment without any changes to the application code. In-page updates
91 are currently not implemented in the Web version, however.
92
93 Notes on In-Page Update Functionality
94 -------------------------------------
95
96 Special note #1: Konqueror seems in certain cases to remember replaced form
97 content (when replaceChild is used to replace regions of the page which
98 include form elements). This causes the browser to believe that more form
99 fields exist on the page than actually do so, and subsequent form submissions
100 thus include the values of such removed fields. A special hack is in place to
101 disable form fields by changing their names, thus causing Konqueror to not
102 associate such fields with the real, active fields; this hack does not seem to
103 cause problems for Mozilla. This needs some investigation to determine in
104 exactly which circumstances the problem arises.
105
106 Special note #2: Konqueror also seems to crash if asked to find elements using
107 an empty 'id' attribute string. This needs some investigation to see if it
108 really is the getElementById call that causes the crash.
109
110 Special note #3: Konqueror's XMLHttpRequest seems to append null characters to
111 the end of field values. Attempting to prune them before the request is sent
112 fails with a function like the following:
113
114 function fixValue(fieldValue) {
115 if (fieldValue.length == 0) {
116 return fieldValue;
117 } else if (fieldValue[fieldValue.length - 1] == '\0') {
118 return fieldValue.substr(0, fieldValue.length - 1);
119 } else {
120 return fieldValue;
121 }
122 }
123
124 This may be because it is the entire message that is terminated with the null
125 character, and that this happens only upon sending the message. Consequently,
126 some frameworks (notably mod_python) do not support in-page functionality when
127 used from Konqueror.
128
129 Various browsers (eg. Mozilla/Firefox, Konqueror) will not allow the
130 XMLHttpRequest in-page updates to function unless the URL used in the
131 requestUpdate JavaScript function is compatible with the URL at which the
132 browser finds the application. Currently, relative URLs are in use to avoid
133 this issue of compatibility, but should an absolute URL be deduced using the
134 WebStack API and then used, it may be possible that the values returned by
135 that API do not match the actual addresses entered into the address bar of the
136 browser.
137
138 To check the behaviour of the applications, it is possible to view the
139 document source of the pages served by applications and to verify that the
140 URLs mentioned in the JavaScript function calls (to 'requestUpdate') either be
141 a relative link or involve a URL similar to that which appears in the
142 browser's address bar. In some environments, the use of 'localhost' addresses
143 often confuses the browser and server; one workaround is to use real host
144 names or addresses instead of 'localhost'.
145
146 Choosing an element-path:
147
148 When specifying the "context" of the in-page update, one must imagine which
149 element the template fragment should operate within. If the template:id
150 attribute marks a particular section, then the element-path should be a path
151 to the applicable context element for that section in the complete template
152 document. Note that if a template:element attribute appears on the same
153 element as the template:id attribute then the element-path should refer to the
154 element specified in the template:element attribute.
155
156 Choosing where to put template:attribute, template:id and id:
157
158 When specifying the extent of a template fragment, one must be sure not to put
159 the template:id attribute on the same element as a template:attribute
160 annotation; otherwise, the generated code will be improperly extracted as a
161 fragment producing two versions of the element - one for when the specified
162 attribute is present, and one for when it is not present. Generally,
163 template:id and id can be placed on the same node, however.
164
165 Stable element ordering and element-path:
166
167 Within the element-path, the numbering of the elements will start at 1.
168 Therefore it is vital to choose a region of the form data structure with the
169 element-path which is isolated from surrounding elements whose positions would
170 otherwise be dependent on a stable ordering of elements, and whose processing
171 would be disrupted if some new elements suddenly appeared claiming the same
172 positions in the document. For example:
173
174 <item value=""> .../item$1/value
175 <type value=""/> .../item$1/type$1/value
176 <comment value=""/> .../item$1/comment$2/value
177 </item>
178
179 In-page update...
180
181 <comment value=""/> .../item$1/comment$1/value
182
183 Notes on XSL
184 ------------
185
186 libxslt seems to be quite liberal on the definition of runtime parameters, in
187 that there is no apparent need to explicitly declare the corresponding global
188 variables in stylesheets. Whilst this is nice, we may eventually need to
189 detect such variables and add them in the preparation process.
190
191 Release Procedures
192 ------------------
193
194 Update the XSLTools/__init__.py and XSLForms/__init__.py __version__
195 attributes.
196 Change the version number and package filename/directory in the documentation.
197 Change code examples in the documentation if appropriate.
198 Update the release notes (see above).
199 Check the setup.py file and ensure that all package directories are mentioned.
200 Check the release information in the PKG-INFO file and in the package
201 changelog (and other files).
202 Tag, export.
203 Generate the API documentation.
204 Remove generated .pyc files: rm `find . -name "*.pyc"`
205 Archive, upload.
206 Upload the introductory documentation.
207 Update PyPI, PythonInfo Wiki, Vaults of Parnassus entries.
208
209 Generating the API Documentation
210 --------------------------------
211
212 In order to prepare the API documentation, it is necessary to generate some
213 Web pages from the Python source code. For this, the epydoc application must
214 be available on your system. Then, inside the distribution directory, run the
215 apidocs.sh tool script as follows:
216
217 ./tools/apidocs.sh
218
219 Some warnings may be generated by the script, but the result should be a new
220 apidocs directory within the distribution directory.
221
222 Making Packages
223 ---------------
224
225 To make Debian-based packages:
226
227 1. Create new package directories under packages if necessary.
228 2. Make a symbolic link in the distribution's root directory to keep the
229 Debian tools happy:
230
231 ln -s packages/ubuntu-hoary/python2.4-xsltools/debian/
232
233 3. Run the package builder:
234
235 dpkg-buildpackage -rfakeroot
236
237 4. Locate and tidy up the packages in the parent directory of the
238 distribution's root directory.