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 * Improved serialisation of transformation results so that output options
50 are observed (in some cases, at least).
51 * Fixed stylesheet and reference document paths so that libxslt should not
52 now become confused by ambiguous relative paths.
53 * Added expression parameters to XSLOutput.Processor so that in-document
54 data can be used to, for example, initialise multiple-choice field values.
55 * Added input/initialiser support so that input documents can be tidied or
56 initialised using information from the template.
57 * Added template:init for use with template:element in XSLForms to control
58 element initialisation where necessary.
59 * Added special high-level "macro" attributes (eg. template:attribute-field)
60 which should make templates easier to write and maintain.
61 * Added template:if to XSLForms, providing conditional output of annotated
62 elements.
63 * Added set_document to XSLForms.Fields.Form.
64 * Added prepare_parameters to XSLForms.Resources.XSLFormsResource.
65 * Added element-path and url-encode XSLForms extension functions.
66 * Improved Unicode support in the XSLForms extension functions.
67 * Changed in-page requests to contain proper POST data.
68 * Updated the code to work with WebStack 1.0 changes and adopted the
69 new-style WebStack demonstration mechanism.
70 * Added XMLCalendar and XMLTable (to the XSLTools package).
71 * Added a dictionary (or word lookup) example application.
72 * Added a job candidate profile (or CV editor) example application.
73 * Added a template attribute reference and an XSLFormsResource guide to the
74 documentation.
75 * Added Debian package support.
76 * Added missing COPYING.txt file.
77 * Renamed the scripts to avoid naming issues in system-wide installations.
78
79 Notes on In-Page Update Functionality
80 -------------------------------------
81
82 Special note #1: Konqueror seems in certain cases to remember replaced form
83 content (when replaceChild is used to replace regions of the page which
84 include form elements). This causes the browser to believe that more form
85 fields exist on the page than actually do so, and subsequent form submissions
86 thus include the values of such removed fields. A special hack is in place to
87 disable form fields by changing their names, thus causing Konqueror to not
88 associate such fields with the real, active fields; this hack does not seem to
89 cause problems for Mozilla. This needs some investigation to determine in
90 exactly which circumstances the problem arises.
91
92 Special note #2: Konqueror also seems to crash if asked to find elements using
93 an empty 'id' attribute string. This needs some investigation to see if it
94 really is the getElementById call that causes the crash.
95
96 Special note #3: Konqueror's XMLHttpRequest seems to append null characters to
97 the end of field values. Attempting to prune them before the request is sent
98 fails with a function like the following:
99
100 function fixValue(fieldValue) {
101 if (fieldValue.length == 0) {
102 return fieldValue;
103 } else if (fieldValue[fieldValue.length - 1] == '\0') {
104 return fieldValue.substr(0, fieldValue.length - 1);
105 } else {
106 return fieldValue;
107 }
108 }
109
110 This may be because it is the entire message that is terminated with the null
111 character, and that this happens only upon sending the message. Consequently,
112 some frameworks (notably mod_python) do not support in-page functionality when
113 used from Konqueror.
114
115 Various browsers (eg. Mozilla/Firefox, Konqueror) will not allow the
116 XMLHttpRequest in-page updates to function unless the URL used in the
117 requestUpdate JavaScript function is compatible with the URL at which the
118 browser finds the application. Currently, relative URLs are in use to avoid
119 this issue of compatibility, but should an absolute URL be deduced using the
120 WebStack API and then used, it may be possible that the values returned by
121 that API do not match the actual addresses entered into the address bar of the
122 browser.
123
124 To check the behaviour of the applications, it is possible to view the
125 document source of the pages served by applications and to verify that the
126 URLs mentioned in the JavaScript function calls (to 'requestUpdate') either be
127 a relative link or involve a URL similar to that which appears in the
128 browser's address bar. In some environments, the use of 'localhost' addresses
129 often confuses the browser and server; one workaround is to use real host
130 names or addresses instead of 'localhost'.
131
132 Choosing an element-path:
133
134 When specifying the "context" of the in-page update, one must imagine which
135 element the template fragment should operate within. If the template:id
136 attribute marks a particular section, then the element-path should be a path
137 to the applicable context element for that section in the complete template
138 document. Note that if a template:element attribute appears on the same
139 element as the template:id attribute then the element-path should refer to the
140 element specified in the template:element attribute.
141
142 Choosing where to put template:attribute, template:id and id:
143
144 When specifying the extent of a template fragment, one must be sure not to put
145 the template:id attribute on the same element as a template:attribute
146 annotation; otherwise, the generated code will be improperly extracted as a
147 fragment producing two versions of the element - one for when the specified
148 attribute is present, and one for when it is not present. Generally,
149 template:id and id can be placed on the same node, however.
150
151 Stable element ordering and element-path:
152
153 Within the element-path, the numbering of the elements will start at 1.
154 Therefore it is vital to choose a region of the form data structure with the
155 element-path which is isolated from surrounding elements whose positions would
156 otherwise be dependent on a stable ordering of elements, and whose processing
157 would be disrupted if some new elements suddenly appeared claiming the same
158 positions in the document. For example:
159
160 <item value=""> .../item$1/value
161 <type value=""/> .../item$1/type$1/value
162 <comment value=""/> .../item$1/comment$2/value
163 </item>
164
165 In-page update...
166
167 <comment value=""/> .../item$1/comment$1/value
168
169 Notes on XSL
170 ------------
171
172 libxslt seems to be quite liberal on the definition of runtime parameters, in
173 that there is no apparent need to explicitly declare the corresponding global
174 variables in stylesheets. Whilst this is nice, we may eventually need to
175 detect such variables and add them in the preparation process.
176
177 Release Procedures
178 ------------------
179
180 Update the XSLTools/__init__.py and XSLForms/__init__.py __version__
181 attributes.
182 Change the version number and package filename/directory in the documentation.
183 Change code examples in the documentation if appropriate.
184 Update the release notes (see above).
185 Check the setup.py file and ensure that all package directories are mentioned.
186 Check the release information in the PKG-INFO file and in the package
187 changelog (and other files).
188 Tag, export.
189 Generate the API documentation.
190 Remove generated .pyc files: rm `find . -name "*.pyc"`
191 Archive, upload.
192 Upload the introductory documentation.
193 Update PyPI, PythonInfo Wiki, Vaults of Parnassus entries.
194
195 Generating the API Documentation
196 --------------------------------
197
198 In order to prepare the API documentation, it is necessary to generate some
199 Web pages from the Python source code. For this, the epydoc application must
200 be available on your system. Then, inside the distribution directory, run the
201 apidocs.sh tool script as follows:
202
203 ./tools/apidocs.sh
204
205 Some warnings may be generated by the script, but the result should be a new
206 apidocs directory within the distribution directory.
207
208 Making Packages
209 ---------------
210
211 To make Debian packages:
212
213 1. Create new package directories under packages/debian if necessary.
214 2. Make a symbolic link in the distribution's root directory to keep the
215 Debian tools happy:
216
217 ln -s packages/debian/python2.4-xsltools/debian/
218
219 3. Run the package builder:
220
221 dpkg-buildpackage -rfakeroot
222
223 4. Locate and tidy up the packages in the parent directory of the
224 distribution's root directory.