% Getting Started with FiveUI
Getting Started with the FiveUI Browser Extension
Once FiveUI has been installed, some initial configuration will need to be done to make the extension useful.
The options page allows the user to configure Rule Sets
that
categorize user interface guidelines into named groups. The options
page also allows the user to set a list of URL Patterns
that each
Rule Set
will analyze.
Rule Sets
define the guidelines, while URL Patterns
state where
the guidelines should run.
Options in Chrome
The options page in Chrome
can be accessed either through the
options link on the extensions page, or through the options item on
the context menu off of the FiveUI button (accessed by right-clicking
on the FiveUI button).
Options in Firefox
The options page in Firefox
can be accessed via the FiveUI gear widget, which
should be added in addition to the FiveUI widget when the addon is installed.
Once clicked, a new tab should appear which serves as the options interface for
the addon.
The FiveUI Widgets are initially placed on the Firefox Add-on bar
,
as shown in the figure.
The Options Page
The options page allows the user to configure Rule Sets
which
categorize user interface guidelines into named groups. Once a Rule
Set
is added, you will be able to set any number of patterns that
determine which web pages the Rule Set
should evaluate.
Rule Sets
Rule Sets
can be managed by clicking on the Rule Sets
tab on the left-hand
side of the options page.
FiveUI loads Rule Sets
from a URL.
Rule Sets
in FiveUi are specified as a JSON object that contains javascript
functions for the rule implementations. Each Rule Set
contains a name,
description and list of zero or more rules. The following snippet
exhibits the minimal definition for a Rule Set
, providing only the name
and description fields, along with an empty set of rules.
javascript
{ "name": "Empty Rules"
, "description": "An example of an empty rule set"
, "rules": []
}
Rules
The elements of the rules array in the Rule Set
are just file paths,
relative to the path of the manifest file. The contents of the file referenced
are javascript, using an exports object to expose the public parts of the rule
API.
The required exports of a rule file are:
- A rule name, called
name
- A description, called 'description`
- A function that will be called as the body of the rule, named
rule
As a simple example, the following rule will log an error for each header tag that contains no text:
javascript
exports.name = 'Disallow Empty Headers';
exports.description = 'Heading elements should contain text';
exports.rule = function(report) {
fiveui.query(':header').each(function(ix, elt) {
if($(elt).text() == '') {
report.error('Heading does not contain text', elt);
}
});
};
Notice that the rule
function is given a report argument that has an error
method exposed, this is how errors are reported back to the extension from the
context of a rule.
Creating a Rule Set
Reusing the previous example and the skeleton of the first, we can create a simple manifest that applies the empty header rule. Enter the following json structure into a file called manifest.json:
javascript
{ "name" : "Header Rule Set"
, "description" : "Simple rules about HTML headers."
, "rules" : [ "emptyHeaders.js" ]
}
As the above manifest references the emptyHeader.js file, we now need to implement that rule. We'll go ahead and use the same example rule that's defined above, placing it in the emptyHeader.js file in the same directory as the manifest that references it.
- Run
python -m SimpleHTTPServer
in the directory that contains manifest.json and exampleHeader.js - Next, open the options page for the FiveUI extension.
- Make sure that the
Rule Sets
tab is selected - Click the
Add
button. - Paste http://localhost:8000/manifest.json into the address field
- Click the save icon (a disk)
You should now see an entry in the Rule Sets
list that includes a add url
pattern
button.
URL Patterns
URL Patterns
can be added by the use of the add url patterns
button on a
rule set, and removed by clicking their x
icon.
URL Patterns
represent the conditions in which a Rule Set
will be applied to
a page. To create a URL Pattern
first make sure that you have created a Rule
Set
with the instructions above. Now you can enter a pattern in the text field
above the add url pattern
button, using the pattern language defined below.
Pattern Language
The pattern text in a URL Pattern
uses the glob character
*, to allow for a URL Pattern
to apply to many URLs. For example, if you
would like to design a pattern that applies to all of the http
pages under the
www.example.com domain, then you could use a pattern such as:
http://www.example.com*
Note that URL Patterns
match the protocol, domain, port and path
portions of the url, so the pattern above will not apply to https
urls. The following pattern will apply to any site hosted at example.com:
*example.com*
Using FiveUI
Once some Rule Sets
and URL Patterns
exist in the FiveUI configuration, the
rules can be applied to a web page. Start off by navigating to a page that
satisfies one of the URL Patterns
defined in the FiveUI options page. If that
URL is matched by one of the patterns, the FiveUI icon will change from gray to
red, and an overlay will display the number of rule violations present on the
page.
The primary user interface is hidden by default, to avoid obscuring the web page inadvertently. To show the list of problems, simply click on the FiveUI icon to make the window visible. The user interface is injected into the running page, and it should display on top of any other user interface elements present.
As the user navigates around sites that are matched by URL Patterns
,
the problem list will have newly occurring problems appended to it.
All state in the dialog is maintained by the extension on a per-tab
basis, so different browser tabs can have distinct lists of problems.
Problems
Problem entries will be added to the FiveUI dialog as rules report problems on the page. Once a problem is reported, the user can click on the arrow to the left of the message to both expand the description of the problem, and to highlight the node of the DOM that is causing the problem. One caveat to this is that if the node that generated the problem exists on a page that has since been navigated away from, the node will obviously not be highlighted.
We illustrate this by first adding a new rule to our example Rule Set. This rule identifies headers that start with a lower-case letter.
javascript
{ "name": "Header Rule Set"
, "description": "Simple rules about HTML headers."
, "rules":
[ "lowerCase.js", "emptyHeaders.js" ]
}
javascript
exports.name = 'Headers should be capitalized';
exports.description = 'Heading elements should not start '
+ 'with lowercase letters.';
exports.rule = function() {
fiveui.query(':header').each(function(ix, elt) {
if( !fiveui.word.capitalized($(elt).text()) ) {
report('Heading is not capitalized', elt);
}
});
};
javascript
exports.name = 'Empty Headers';
exports.description = 'Heading elements should contain text.';
exports.rule = function() {
fiveui.query(':header').each(function(ix, elt) {
if($(elt).text() == '') {
report('Heading does not contain text', elt);
}
});
};
This sample Rule Set
demonstrates some new capabilities:
* Multiple rules in one Rule Set.
* Multi-line descriptions.
* The fiveui.word.capitalized(...)
predicate, from the FiveUI prelude
.
The FiveUI Prelude
is a small collection of utilities for creating rules.
Once adding this Rule Set
specifying a URL Pattern
, we can view
violations in the FiveUI Problem List. Clicking on the expand arrow
for a specific problem will highlight the element of the DOM that
caused the violation.
Where to go from here
For more detail on the API available when writing new rules, see the Javascript documentation.
Headless
is a tool for automated rule set checking using FiveUI.
To get started with Headless, see Headless documentation.