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