XSLTools

README.txt

515:89e049d9c606
2006-03-04 paulb [project @ 2006-03-04 18:53:46 by paulb] Updated the release notes.
     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                  0.3.3
    40 libxml2                     Tested with 2.6.17
    41 libxslt                     Tested with 1.1.12
    42 
    43 The example Web applications require WebStack (release 1.1.2 or later).
    44 The example PyQt applications have been tested with PyQt 3.15.
    45 
    46 New in XSLTools 0.4 (Changes since XSLTools 0.3.1)
    47 --------------------------------------------------
    48 
    49   * Changed the preparation of templates to produce rule-based output
    50     stylesheets, thus permitting recursive templates. This requires an extra
    51     expr-prefix annotation to be used in certain kinds of templates.
    52   * Added a recursive template example application.
    53   * Changed fragment production to use original template documents instead of
    54     output stylesheets.
    55   * Changed the in_page_resources attribute to provide the output identifier,
    56     thus changing the prepare_fragment method in Web resources so that only
    57     the fragment identifier needs to be supplied.
    58   * Added the XSLForms.Resources.WebResources.prepare_resources method for the
    59     preparation of initialiser and output stylesheets before an application is
    60     run.
    61   * Changed selectors to not automatically create elements in the form data
    62     document unless requested to do so. Introduced a Form.get_selector
    63     method in XSLForms.Fields.
    64   * Introduced dynamic parameter evaluation for multiple-choice fields in
    65     order to support sources of multiple-choice values which reside in the
    66     form data document itself.
    67   * Added the FixNamespace.xsl stylesheet to correct documents saved by HTML
    68     editors which strip namespace prefixes.
    69   * Fixed filesystem encoding issues in the Candidate example; fixed language
    70     preference access in the Configurator and VerySimple examples.
    71   * Changed the BaseHTTPRequestHandler version of the Candidate example to
    72     store data in a subdirectory of the current working directory, thus
    73     allowing the demonstration application to work after package installation.
    74 
    75 New in XSLTools 0.3.1 (Changes since XSLTools 0.3)
    76 --------------------------------------------------
    77 
    78   * Fixed copyright and licensing information.
    79 
    80 New in XSLTools 0.3 (Changes since XSLTools 0.2)
    81 ------------------------------------------------
    82 
    83   * Introduced copying of multiple-choice value element contents so that
    84     option element labels can differ from the underlying values.
    85   * Added internationalisation support, providing the template:i18n annotation
    86     and the template:i18n extension function.
    87   * Updated the documentation to cover the above new features.
    88   * Fixed non-GET/POST request method handling in WebResources.
    89   * Added the xslform_preparemacro.py script.
    90   * Added an experimental template:range extension function.
    91 
    92 New in XSLTools 0.2 (Changes since XSLTools 0.1)
    93 ------------------------------------------------
    94 
    95   * Made a new XSLTools package and moved XSLOutput into it.
    96   * Improved serialisation of transformation results so that output options
    97     are observed (in some cases, at least).
    98   * Fixed stylesheet and reference document paths so that libxslt should not
    99     now become confused by ambiguous relative paths.
   100   * Added expression parameters to XSLOutput.Processor so that in-document
   101     data can be used to, for example, initialise multiple-choice field values.
   102   * Added input/initialiser support so that input documents can be tidied or
   103     initialised using information from the template.
   104   * Added template:init for use with template:element in XSLForms to control
   105     element initialisation where necessary.
   106   * Added special high-level "macro" attributes (eg. template:attribute-field)
   107     which should make templates easier to write and maintain.
   108   * Added template:if to XSLForms, providing conditional output of annotated
   109     elements.
   110   * Added set_document to XSLForms.Fields.Form.
   111   * Added prepare_parameters to the XSLFormsResource class in the
   112     XSLForms.Resources.WebResources module.
   113   * Added element-path, url-encode and choice XSLForms extension functions.
   114   * Improved Unicode support in the XSLForms extension functions.
   115   * Changed in-page requests to contain proper POST data.
   116   * Fixed checkbox and radiobutton value detection in XSLForms.js.
   117   * Updated the code to work with WebStack 1.0 changes and adopted the
   118     new-style WebStack demonstration mechanism.
   119   * Added XMLCalendar and XMLTable (to the XSLTools package).
   120   * Added a dictionary (or word lookup) example application.
   121   * Added a job candidate profile (or CV editor) example application.
   122   * Added a template attribute reference and an XSLFormsResource guide to the
   123     documentation.
   124   * Added Debian package support (specifically Ubuntu package support).
   125   * Added missing COPYING.txt file.
   126   * Renamed the scripts to avoid naming issues in system-wide installations.
   127   * Added a PyQt example based on the system configurator example, with the
   128     form prepared in Qt Designer. This example runs in PyQt and in a Web
   129     environment without any changes to the application code. In-page updates
   130     are currently not implemented in the Web version, however.
   131 
   132 Notes on In-Page Update Functionality
   133 -------------------------------------
   134 
   135 Special note #1: Konqueror seems in certain cases to remember replaced form
   136 content (when replaceChild is used to replace regions of the page which
   137 include form elements). This causes the browser to believe that more form
   138 fields exist on the page than actually do so, and subsequent form submissions
   139 thus include the values of such removed fields. A special hack is in place to
   140 disable form fields by changing their names, thus causing Konqueror to not
   141 associate such fields with the real, active fields; this hack does not seem to
   142 cause problems for Mozilla. This needs some investigation to determine in
   143 exactly which circumstances the problem arises.
   144 
   145 Special note #2: Konqueror also seems to crash if asked to find elements using
   146 an empty 'id' attribute string. This needs some investigation to see if it
   147 really is the getElementById call that causes the crash.
   148 
   149 Special note #3: Konqueror's XMLHttpRequest seems to append null characters to
   150 the end of field values. Attempting to prune them before the request is sent
   151 fails with a function like the following:
   152 
   153 function fixValue(fieldValue) {
   154     if (fieldValue.length == 0) {
   155         return fieldValue;
   156     } else if (fieldValue[fieldValue.length - 1] == '\0') {
   157         return fieldValue.substr(0, fieldValue.length - 1);
   158     } else {
   159         return fieldValue;
   160     }
   161 }
   162 
   163 This may be because it is the entire message that is terminated with the null
   164 character, and that this happens only upon sending the message. Consequently,
   165 some frameworks (notably mod_python) do not support in-page functionality when
   166 used from Konqueror.
   167 
   168 Various browsers (eg. Mozilla/Firefox, Konqueror) will not allow the
   169 XMLHttpRequest in-page updates to function unless the URL used in the
   170 requestUpdate JavaScript function is compatible with the URL at which the
   171 browser finds the application. Currently, relative URLs are in use to avoid
   172 this issue of compatibility, but should an absolute URL be deduced using the
   173 WebStack API and then used, it may be possible that the values returned by
   174 that API do not match the actual addresses entered into the address bar of the
   175 browser.
   176 
   177 To check the behaviour of the applications, it is possible to view the
   178 document source of the pages served by applications and to verify that the
   179 URLs mentioned in the JavaScript function calls (to 'requestUpdate') either be
   180 a relative link or involve a URL similar to that which appears in the
   181 browser's address bar. In some environments, the use of 'localhost' addresses
   182 often confuses the browser and server; one workaround is to use real host
   183 names or addresses instead of 'localhost'.
   184 
   185 Choosing an element-path:
   186 
   187 When specifying the "context" of the in-page update, one must imagine which
   188 element the template fragment should operate within. If the template:id
   189 attribute marks a particular section, then the element-path should be a path
   190 to the applicable context element for that section in the complete template
   191 document. Note that if a template:element attribute appears on the same
   192 element as the template:id attribute then the element-path should refer to the
   193 element specified in the template:element attribute.
   194 
   195 Choosing where to put template:attribute, template:id and id:
   196 
   197 When specifying the extent of a template fragment, one must be sure not to put
   198 the template:id attribute on the same element as a template:attribute
   199 annotation; otherwise, the generated code will be improperly extracted as a
   200 fragment producing two versions of the element - one for when the specified
   201 attribute is present, and one for when it is not present. Generally,
   202 template:id and id can be placed on the same node, however.
   203 
   204 Stable element ordering and element-path:
   205 
   206 Within the element-path, the numbering of the elements will start at 1.
   207 Therefore it is vital to choose a region of the form data structure with the
   208 element-path which is isolated from surrounding elements whose positions would
   209 otherwise be dependent on a stable ordering of elements, and whose processing
   210 would be disrupted if some new elements suddenly appeared claiming the same
   211 positions in the document. For example:
   212 
   213   <item value="">         .../item$1/value
   214     <type value=""/>      .../item$1/type$1/value
   215     <comment value=""/>   .../item$1/comment$2/value
   216   </item>
   217 
   218   In-page update...
   219 
   220   <comment value=""/>     .../item$1/comment$1/value
   221 
   222 Notes on XSL
   223 ------------
   224 
   225 libxslt seems to be quite liberal on the definition of runtime parameters, in
   226 that there is no apparent need to explicitly declare the corresponding global
   227 variables in stylesheets. Whilst this is nice, we may eventually need to
   228 detect such variables and add them in the preparation process.
   229 
   230 Release Procedures
   231 ------------------
   232 
   233 Update the XSLTools/__init__.py and XSLForms/__init__.py __version__
   234 attributes.
   235 Change the version number and package filename/directory in the documentation.
   236 Change code examples in the documentation if appropriate.
   237 Update the release notes (see above).
   238 Check the setup.py file and ensure that all package directories are mentioned.
   239 Check the release information in the PKG-INFO file and in the package
   240 changelog (and other files).
   241 Tag, export.
   242 Generate the example resources.
   243 Generate the API documentation.
   244 Remove generated .pyc files: rm `find . -name "*.pyc"`
   245 Archive, upload.
   246 Upload the introductory documentation.
   247 Update PyPI, PythonInfo Wiki, Vaults of Parnassus entries.
   248 
   249 Generating the Example Resources
   250 --------------------------------
   251 
   252 In order to prepare the example resources, the prepare_demo.py script must be
   253 run as follows:
   254 
   255 python tools/prepare_demo.py
   256 
   257 This will ensure that all initialiser and output stylesheets are created and
   258 are thus installed by packages.
   259 
   260 Generating the API Documentation
   261 --------------------------------
   262 
   263 In order to prepare the API documentation, it is necessary to generate some
   264 Web pages from the Python source code. For this, the epydoc application must
   265 be available on your system. Then, inside the distribution directory, run the
   266 apidocs.sh tool script as follows:
   267 
   268 ./tools/apidocs.sh
   269 
   270 Some warnings may be generated by the script, but the result should be a new
   271 apidocs directory within the distribution directory.
   272 
   273 Making Packages
   274 ---------------
   275 
   276 To make Debian-based packages:
   277 
   278   1. Create new package directories under packages if necessary.
   279   2. Make a symbolic link in the distribution's root directory to keep the
   280      Debian tools happy:
   281 
   282      ln -s packages/ubuntu-hoary/python2.4-xsltools/debian/
   283 
   284   3. Run the package builder:
   285 
   286      dpkg-buildpackage -rfakeroot
   287 
   288   4. Locate and tidy up the packages in the parent directory of the
   289      distribution's root directory.