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