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