WebHelpers / docs / whats_new.rst

What's New in WebHelpers

This is a high-level overview of recent changes. Incompatible changes are in boldface; these may require modifying your application. See Changelog for the full changelog.

Version 1.2

webhelpers.html: The HTML builder now uses Armin Ronacher's "MarkupSafe" package, which Mako and Pylons have also switched to. MarkupSafe has a C speedup for escaping, escapes single-quotes for greater security (to close a potential XSS attack route), and adds new methods to literal. literal is now a subclass of markupsafe.Markup; escape is a wrapper for markupsafe.escape_silent.

webhelpers.html.tags: The text() helper has a "type" argument for new HTML 5 input types.

webhelpers.html.tags: No longer adds an "id" attribute to hidden fields generated by the ``form()`` helper, to prevent IDs from clashing if the page contains multiple forms. To create a hidden field with an ID, call hidden() directly.

webhelpers.util: update_params now supports query parameters with multiple values.

Version 1.1

webhelpers.pylonslib.minify: The Javascript minification code was removed due to a non-free license. The helper now minifies Javascript only if the "jsmin" package is installed. Otherwise it issues a warning and leaves the Javascript unchanged. CSS minification is not affected. Details are in webhelpers/pylonslib/ .

Version 1.0

WebHelpers 1.0 has a lot of new features compared to 0.6.4. Several modules deprecated in 0.6.4 were removed, but otherwise there are only a few API incompatibilties with the 0.6 series.

Deleted packages

The following deprecated packages were removed: rails, commands, hinclude, htmlgen, pagination, and string24. Most of the functionality of the rails helpers was replaced by new helpers in the date, html, misc, number, and text packages. Prototype and Scriptaculous are not replaced; WebHelpers no longer ships with Javascript libraries. pagination was replaced by paginate. number_to_human_size() is in the unfinished directory in the source distribution; you can copy it to your application if you need it. If you can't switch to the replacement helpers, stick with WebHelpers 0.6.4.


webhelpers.html.secure_form was moved to webhelpers.pylonslib.secure_form because it depends on Pylons.


uk_counties() now returns tuples rather than strings.


webhelpers.feedgenerator was upgraded to the Django original (December 2009 version), and the "Geo" classes were added for geographical (GIS) feeds. Points are latitude/longitude by default, but there's a flag if your data is longitude first (as Django is). A Geometry class was reverse engineered for other geometries, but it's untested. Add a "published" property for Atom feeds.


New method for producing CDATA sections. The basic tag builders have a _nl flag to add a newline between content elements and after the tag for readability.


markdown() adds an argument to choose a Markdown implementation. The Markdown included in WebHelpers will remain at version 1.7, but Markdown 2.x is available on PyPI, and a separate implementation confusingly called "Markdown2" is also available on PyPI.


New helpers to render HTML to text, and to sanitize user input by stripping HTML tags.


New helpers to add CSS classes to a tag programmatically, to support option groups in <select> tags, and to generate <!doctype> and <?xml ?> declarations.

image() can calculate the width and height of an image automatically, using either the Python Imaging Library (PIL) or a pure Python algorithm in

form() puts its hidden "_method" field in a <div> for XHTML compliance, and the hidden() helper has a magic ID attribute to match the other helpers.

Ported js_obfuscate() from the old rails helpers.

highlight() adds new arguments for flexibility, and is reimplemented using the HTML builder. The 'highlighter' argument is deprecated.


New helpers to flatten nested lists and tuples, and to gather all the subclasses of a specified class. There's an exception OverwriteError, a DeclarativeException class for making your own exceptions with constant messages, and a deprecate functioand n.


format_data_size() and its derivatives format_byte_size() and format_bit_size() provide a convenient way to display numbers using SI units ("1.2 kilobytes", "1.2 kB", "1.0 KiB").


webhelpers.paginate has a new algorithm for generating URLs for page links, has some enhancements for Javascript, works with all versions of SQLAlchemy 0.4 and higher, and has a presliced list option.

On Pylons it will use pylons.url.current as the URL generator, or fall back to routes.url_for if that is not available. You can also pass a callback function to the constructor to implement a custom generator. If none of these are available, you'll get a NotImplementedError. Previous versions of WebHelpers (through 1.0b5) used routes.url_for unconditionally, but that function is deprecated and is not supported in Pylons 1.x.


webhelpers.pylonslib is now a package. The Flash class accepts severity categories, which you can use to style more severe messages differently. The session structure is different, so delete existing HTTP sessions when upgrading.


webhelpers.text adds a suite of helpers from Ruby's stringex package to convert strings to URL-friendly format, and to remove inconvenient accents from characters, etc.


New helper to update the query parameters in a URL.

Experimental code

webhelpers.html.grid and webhelpers.pylonslib.grid contain helpers to make an HTML table from a list of objects such as database records. It has a demo program and an optional stylesheet. It's "experimental" because the docs aren't very clear and the API could maybe do with some changes. But it works.

webhelpers.pylonslib.minify contains versions of javascript_link() and stylesheet_link() that compress their files. It's experimental because their tests fail, so they probably don't work.

Other experiments are in the "unfinished" directory in the source distribution.

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