W3C mobileOK Basic Tests 1.0

This draft reflects an important structural change since the last draft: the single mobileOK Scheme document has been split into three: mobileOK Basic Tests, mobileOK Tests, and mobileOK Labels. The documents describe the test suite for mobileOK Basic, mobileOK, and the mobileOK content labels, respectively. At this time, the group is publishing a draft of only the mobileOK Basic Tests document. Work on other documents is still ongoing.

This document further reflects substantial changes in the tests themselves based on feedback and group discussions since the last public draft.

1 Introduction

This document describes W3C MobileOK Basic tests which are based on Mobile Web Best Practices [BestPractices].

mobileOK Basic is the lesser of two levels of claim, the higher level being mobileOK, described separately. Claims to be W3C mobileOK Basic are represented using content labels, also described separately.

The intention of mobileOK is to help catalyze development of Web sites that provide a functional user experience in a mobile context.

1.1 Levels of mobileOK

Two levels of mobile OK tests are defined: "mobileOK Basic" and "mobileOK".

1.1.1 mobileOK Basic

mobileOK Basic tests are based upon a limited subset of the Mobile Web Best Practices and are all machine-verifiable, hence conformance to mobileOK Basic is simple to check or verify.

Content passing the tests demonstrates that the content provider has taken basic steps to provide a functional experience for mobile users.

mobileOK Basic compliance should be considered only a first step towards building a harmonized experience for mobile users. Compliance merely demonstrates that a basic experience is available, interoperable with a large number of mobile devices. mobileOK Basic compliance says nothing about richer, more sophisticated experiences that the resource may also be able to provide.

1.1.2 mobileOK

The (full) mobileOK tests include the Basic tests and are based upon a larger subset of Best Practices. These tests are not all machine-verifiable.

Content passing the tests demonstrates that the content provider has taken significant steps to provide a functional experience for mobile users. However, mobileOK compliance still does not suggest that the most sophisticated mobile user experience possible is available. It implies that a functional experience is available which adheres even more closely to Best Practices defined in [BestPractices].

mobileOK tests will be described in a forthcoming mobileOK Tests document.

1.1.3 Out of Scope

Note that not all Mobile Web Best Practices map to a test in mobileOK conformance tests. Some best practices, like TESTING, are advisable but do not meaningfully translate into concrete tests, whether machine- or human-verifiable.

mobileOK does not assess the usability of a Web site. It assesses whether the content can be provided in a way that is likely to achieve a basic level of interoperability with mobile devices.

The tests are not promoted as a guideline for achieving the optimal user experience. Many devices go well beyond the basic specifications assumed by these tests. It will often be possible, and generally desirable, to provide an interface designed to take advantage of the extra capabilities.

Content providers should provide an interface that is mobileOK conformant to ensure a basic level of interoperability. Providers are encouraged to provide enhanced versions as well, when these are appropriate to their application and devices that are accessing them.

1.2 Applicability

The tests apply to a URI (or group of URIs). Passing the tests means that under the right circumstances, accessing that URI will retrieve content that conforms to the criteria defined, and that its delivery also conforms. That is to say that the tests do not apply solely to content or document instances. Many best practices relate not just to the document (e.g. well-formed markup), but to how it is delivered to a mobile device (e.g. the presence of caching headers in the HTTP response). For convenience, this document will hereafter refer to "mobileOK content" with the understanding that mobileOK labels apply to more than just the content itself.

mobileOK says nothing about what may be delivered to non-mobile devices from that URI; however, note that a mobileOK URI must return mobileOK content by default if the nature of the user agent cannot be reliably determined.

1.3 Claiming mobileOK conformance

A standard mechanism will be defined that allows content providers to make the claim that their content conforms to mobileOK at either the lower or the higher level. The manner of making claims will be in the form of a machine processable content label. It will be possible to notify users by means of a logo and by provision of human readable equivalent of the label.

A mobileOK content label does not imply endorsement or suitability of content. For example, it must not be assumed that mobileOK content is of higher informational value, is more reliable, more trustworthy or is appropriate for children.

MobileOK content labels will be described in mobileOK Content Labels [ContentLabels].

1.4 Who is mobileOK for?

mobileOK has value at many points in the content authoring and delivery chain for mobile devices:

Content Developers: Developers who create content which follows Mobile Web Best Practices, and which passes tests outlined in this document, have added value for mobile users. They can advertise this to consumers of their content through the mobileOK labels.
Tools: Likewise, tools that can produce, parse, adapt or manipulate mobileOK content (browsers, content management systems, authoring tools, content adaptation systems, etc.) add value for authors, and can advertise this capability.
Content Providers: Sites that are concerned with providing a quality experience to mobile users can look for a mobileOK label when acquiring content and tools.
Content Discovery Services: Search engines, content aggregators, and other services which locate content for mobile devices can look for a mobileOK label and possibly prioritize mobileOK content.
Content Consumers: End consumers of content may also treat mobileOK content differently, preferring sites that advertise mobileOK content.
Certification Providers: Certification providers may wish to offer to certify conformance to mobileOK tests; entities such as content providers that come to rely on mobile content may require more verification that content they provide is mobileOK.

2 Conformance

This section details the tests that must be carried out in order to claim mobileOK Basic. Tests are presented as simple pseudo-code.

2.1 Validity of the Tests

mobileOK tests apply to HTML content delivered over HTTP.

2.2 Testing Outcomes

Individual rests may result have result of PASS or FAIL. PASS is required from all tests in order to claim mobileOK Basic.

In addition to generating a PASS or FAIL tests may also generate a number of informative WARNs whose purpose is to alert the tester that in some circumstances the content being assessed may contravene Best Practices.

2.3 Conduct of Tests

mobileOK Basic does not prescribe the order in which tests are to be carried out. Tests have been formulated to be executed independently. In order to allow for a testing environment in which as much information as possible is made available, some tests have been designed to assess aspects that are not allowed by other tests. For example the test for 3.23 STYLE_SHEETS_USE points out that style sheets should be used in preference to markup elements such as bold, even though the bold element is also disallowed by the test for 3.3 CONTENT_FORMAT_SUPPORT.

Creators of implementations of the tests described in this document are encouraged to provide as much information as possible to users of their implementations. Where possible they should not stop on FAIL and specifically they should:

Continue individual tests as far as is possible
Carry out as many tests as is reasonable

2.4 Testing Parameters

All tests assume that the document and responses should be compatible with a device matching the Default Delivery Context's profile.

Tests are to be conducted using the parameters below.

2.4.1 HTTP Request

Include a User-Agent header indicating the default delivery context:

User-Agent: W3C mobileOK DDC (http://www.w3.org/2006/07/mobileok-ddc)

Include an Accept header indicating that Internet media types understood by the default delivery context are accepted:
```
Accept: application/xhtml+xml,text/css,image/jpeg,image/gif
```
Editor's Note: The group is still debating whether to include the other acceptable Internet media types for XHTML Basic, "application/xml" and "text/xml", in this header. The group is also debating whether to include the XHTML MP Internet media type of "application/vnd.wap.xhtml+xml".
Include an Accept-Charset header indicating that UTF-8 is accepted:
```
Accept-Charset: UTF-8
```

2.4.2 Style Information

Some tests refer to "CSS Style" information. Assemble the CSS Style by using the contents of:

style elements
resources linked by xml-stylesheet processing instructions
resources linked by link elements or HTTP link headers that specify "stylesheet" as the value of their rel attribute
resources linked by CSS @import at-rules

In the course of assembling the CSS Style:

observe the CSS Level 1 cascade
ignore those resources and style elements specified as having an Internet media type other than "text/css"
if a preferred style is specified, use only those resources and ignore alternative style resources
retrieve only those resources that have no CSS media type, or whose CSS media type is "handheld" or "all"
use only those rules that are not restricted as to their CSS media type or whose media type is "handheld" or "all"

3 mobileOK Basic Tests

This section describes tests for mobileOK Basic. Tests are organized alphabetically by the Best Practice from which they derive. Where a test derives from more than one Best Practice it is placed according to the one that occurs earliest in dictionary order.

3.1 AUTO_REFRESH (partial) and REDIRECTION

This test does not determine whether the user is able to opt out of refresh.

If a meta element is present with http-equiv attribute value of "refresh",

If the URI specified is not the current page, FAIL

WARN

If a Refresh HTTP header is present,

If the URI specified in the header value is not the current page, FAIL

WARN

PASS

3.2 CHARACTER_ENCODING_SUPPORT and CHARACTER_ENCODING_USE

If no character encoding is specified in the Content-Type HTTP header and it defaults to something other than UTF-8 ("text/html" is a notable example, as it implies the ISO-8859-1 character encoding), or, if a character encoding is present and it is not UTF-8 (for example, "application/xhtml+xml;charset=Shift_JIS"), FAIL

If the encoding attribute of the XML header is present and is set to anything other than UTF-8, FAIL

If the document is not valid UTF-8, FAIL

For each resource linked via a link or style element, request the resource:

If the character encoding is not specified in HTTP response Content-Type header or the response specifies an Internet media type starting with "text/" and the character encoding is not "UTF-8", WARN

PASS

3.3 CONTENT_FORMAT_SUPPORT

If the document's Internet media type, as specified in the HTTP response Content-Type header, is not "application/xhtml+xml" or "text/html", FAIL

Editor's Note: The group is still debating whether to include the other acceptable Internet media types for XHTML Basic, "application/xml" and "text/xml", in this header. The group is also debating whether to include the XHTML MP Internet media type of "application/vnd.wap.xhtml+xml".

If the document's Internet media type is "text/html", WARN

If the document does not validate against the XHTML Basic 1.1 DTD, FAIL

For each resource linked via an img, link, style element or @import statement within a stylesheet, request the resource:

If the response specifies an Internet media type that is not "text/css", "image/jpeg" or "image/gif", FAIL

If the Internet media type is "image/gif" or "image/jpeg", and the resource is invalid according to the specification of GIF89a or JPEG, respectively, FAIL

If the Internet media type is "text/css" and the content is not well-formed CSS (contains mismatching brackets or illegal characters), FAIL

PASS

3.4 DEFAULT_INPUT_MODE

For example, a text input control that accepts a quantity should only receive numeric input, and therefore should set the inputmode attribute to "user digits". Note that inputmode is part of [XHTML11].

For each input element with attribute type whose value is "text", or textarea element:

If the element is empty and an inputmode attribute is not present, WARN

PASS

3.5 EXTERNAL_RESOURCES

Editor's Note: The group would like to solicit feedback on the limits imposed by this test. Are 10 and 20 reasonable? Should there be a hard FAIL at a number like 20 or only a WARN limit?

If the total number of unique external resources referenced by style, img, link, or object elements exceeds 10, WARN

If this total exceeds 20, FAIL

PASS

3.6 GRAPHICS_FOR_SPACING

For each img element:

If all pixels are transparent and image dimensions are 2x2 or less, WARN

PASS

3.7 IMAGE_MAPS

If an area element is present, FAIL

For each img element:

If a usemap attribute is present, FAIL

PASS

3.8 IMAGES_RESIZING and IMAGES_SPECIFY_SIZE

For each img element:

If the image has an intrinsic size,

If the height or width attribute are missing, FAIL

If the height or width attribute do not specify a size in pixels, FAIL

If height and width specified do not match the size of the image, FAIL

PASS

3.9 LARGE_GRAPHICS

No test is defined specifically for this Best Practice, since tests for IMAGES_RESIZING and SCROLLING already cover its requirements in mobileOK Basic

3.10 LINK_TARGET_FORMAT

For each a element:

Issue an HTTP GET request for the URI referenced in the href attribute

If the HTTP response's Content-Type header is not "application/xhtml+xml", "text/html", "text/css", "image/jpeg" or "image/gif", WARN

Editor's Note: See above notes on application/xml, text/xml and application/vnd.wap.xhtml+xml in this context.

PASS

3.11 MEASURES

For each numeric measure in the CSS Style:

If the unit is not "em", "ex" or "%", FAIL

PASS

3.12 `<meta>` element consistency with HTTP header

This test does not map to a specific best practice. It merely provides warnings deemed useful to developers.

For each meta element with an http-equiv attribute:

If an HTTP header is present whose name matches the http-equiv attribute's value,

If the header's value does not match the meta element's content attribute, WARN

PASS

3.13 MINIMIZE

Count number of whitespace characters in a sequence of more than one whitespace character (not counting the first), which exist outside of a pre, style or script element

Add to this count the number of characters comprising XML comments. This total is the number of extraneous characters in the document.

Count total number of characters in document

If the number of extraneous characters exceeds 10% of the count of characters in the document, WARN

If the number of extraneous characters exceeds 25% of the count of characters in the document, FAIL

PASS

3.14 NO_FRAMES

If the document contains a frame , frameset or iframe element, FAIL

PASS

3.15 NON-TEXT_ALTERNATIVES (partial)

This test does not determine whether the alternative text is meaningful.

For each img element:

If an alt attribute is not present, FAIL

PASS

3.16 OBJECTS_OR_SCRIPT (partial)

This test does not determine whether the document is still usable without the objects or scripts.

If a script element is present, WARN

If an applet element is present, FAIL

If an object element is present,

If the element is empty, WARN

If element body is non-empty and does not consist of text or an img element that refer to an image in a supported format, FAIL

PASS

3.17 PAGE_SIZE_LIMIT

If the size of the document's markup exceeds 10 kilobytes, FAIL

If the size of the document's markup plus its linked resources exceeds 20 kilobytes, FAIL

PASS

Note: To calculate the size of the linked resources, add up the size of each included style sheet (see 2.4.2 Style Information), image, and object of the appropriate type.

3.18 PAGE_TITLE (partial)

This test does not determine whether the title is meaningful.

If a title element is not present in the head element, or is empty, FAIL

PASS

3.19 POP_UPS

For each a, link, form, base element:

If a target attribute is present,

If its value is not one of "_self", "_parent", or "_top", FAIL

PASS

3.20 PROVIDE_DEFAULTS (partial)

In addition, a human-verifiable test is needed here to verify whether such elements could be replaced with alternative control elements.

For each input element:

If element's type attribute is "radio",

If the document contains no input element whose name attribute's value matches that of this radio input, and whose checked attribute is set to some value, WARN

For each select element:

If there is no nested option element whose selected attribute is set to some value, WARN

PASS

3.21 SCROLLING (partial)

This test does not determine whether secondary scrolling created by wide objects can be avoided, nor does it catch all possible objects which may render wider than 120 pixels.

Editor's Note: This is a relatively simple test that detects some situations in which an element is forced to render wider than 120 pixels. It does not detect all such situations as this would really require fully rendering the page. The group would like to solicit feedback on this test: whether it can be tightened without adding much complexity, and whether it is consistent with how most mobile browsers would render pages. We wish to avoid false positives: would this test WARN on a page that most mobile browsers render less than 120 pixels wide?

For each block-level element, which includes those whose CSS property display is "block", either by default or explicitly set, as well as the body, img, and object elements:

If CSS property width is set in pixels, or, the element has a width attribute

Add to the property/attribute value the value of the following CSS box properties if set in pixels:

border-left-width, border-right-width (may also be set by border-width, border-left, border-right, border)

margin-left, margin-right (may also be set by margin)

padding-left, padding-right (may also be set by padding)

If the sum exceeds 120, WARN

Otherwise, for each of the parent elements, its parent, and so on up to the document root:

Add to that sum the values of the border, margin and padding properties as above

If the sum exceeds 120, WARN

Otherwise continue with the next parent

For each table element:

Add together its border, margin and padding property values as above

For each contained tr element:

Add to the sum its border, margin and padding property values

For each contained td or th element:

Add to the sum its border, margin and padding property values

If the sum exceeds 120, WARN

PASS

3.22 STYLE_SHEETS_SUPPORT (partial)

In addition, a human test is needed here to verify whether the page is readable without a style sheet.

If the CSS Style contains rules involving the display or float properties, WARN

PASS

3.23 STYLE_SHEETS_USE

This test does not require that any CSS styles be used, since in some cases, no presentation information is required at all (for example, a simple page of text).

This test looks for elements in the Text Extension module defined by [XHTMLModularization], since these are not supported in XHTML Basic. It also looks for commonly-used elements that were deprecated in HTML 4, and are also not supported in XHTML Basic.

If the document contains any b, basefont, bdo, big, center, del, dir, font, i, ins, menu, s, small, strike, sub, sup, tt, or u elements, FAIL

If there is no CSS Style, PASS

If the document contains a CSS style element but no externally linked CSS Style, WARN

If the CSS Style contains a single @media rule that specifies the media type screen, WARN

If the CSS Style contains at-rules other than the @media at-rule, properties or values that are not recognized as being valid CSS Level 1, WARN

PASS

3.24 TABLES_ALTERNATIVES

If a table element exists, WARN

Editor's note: This test is tentative. The group would like to solicit feedback on this test. All that a machine may reasonably do to check compliance with Best Practice is warn about any use of table. It is not clear whether legitimate uses of table are infrequent enough that this warning will be more useful than a nuisance or not.

3.25 TABLES_LAYOUT (partial)

This test does not catch all cases where tables are used for layout purposes.

If a table element exists,

If it contains less than two tr elements, FAIL

If no tr element contains at least two td elements, FAIL

For each nested td element:

If the element is empty, or contains an image whose real dimensions are 2x2 or less, FAIL

PASS

3.26 TABLES_NESTED

If a table element exists,

If a table element exists somewhere inside it, FAIL

PASS

3.27 VALID_MARKUP

If it is an HTML document and it fails to validate according to its given DOCTYPE, FAIL

PASS

Best Practice	mobileOK Basic	mobileOK
ACCESS_KEYS		X
AUTO_REFRESH	X	X
AVOID_FREE_TEXT		X
BACKGROUND_IMAGE_READABILITY		X
BALANCE
CACHING		X
CAPABILITIES
CENTRAL_MEANING
CHARACTER_ENCODING_SUPPORT	X
CHARACTER_ENCODING_USE	X
CLARITY
COLOR_CONTRAST		X
CONTENT_FORMAT_PREFERRED		X
CONTENT_FORMAT_SUPPORT	X
CONTROL_LABELLING		X
CONTROL_POSITION		X
COOKIES		X
DEFAULT_INPUT_MODE	X
DEFICIENCIES
ERROR_MESSAGES		X
EXTERNAL_RESOURCES	X
FONTS		X
GRAPHICS_FOR_SPACING	X
IMAGE_MAPS	X
IMAGES_RESIZING	X
IMAGES_SPECIFY_SIZE	X
LARGE_GRAPHICS	X
LIMITED		X
LINK_TARGET_FORMAT	X
LINK_TARGET_ID		X
MEASURES	X
MINIMIZE	X
MINIMIZE_KEYSTROKES		X
NAVBAR		X
NAVIGATION		X
NO_FRAMES	X
NON-TEXT_ALTERNATIVES	X	X
OBJECTS_OR_SCRIPT	X	X
PAGE_SIZE_LIMIT	X
PAGE_SIZE_USABLE		X
PAGE_TITLE	X	X
POP_UPS	X
PROVIDE_DEFAULTS	X	X
REDIRECTION	X
SCROLLING	X	X
STRUCTURE		X
STYLE_SHEETS_SIZE
STYLE_SHEETS_SUPPORT	X	X
STYLE_SHEETS_USE	X
SUITABLE	X
TAB_ORDER		X
TABLES_ALTERNATIVES	X
TABLES_LAYOUT	X	X
TABLES_NESTED	X
TABLES_SUPPORT
TESTING
THEMATIC_CONSISTENCY
URIS
USE_OF_COLOR		X
VALID_MARKUP	X

W3C mobileOK Basic Tests 1.0

W3C Working Draft 13 November 2006

Abstract

Status of this Document

Revision Description

Table of Contents

Appendices

1 Introduction

1.1 Levels of mobileOK

1.1.1 mobileOK Basic

1.1.2 mobileOK

1.1.3 Out of Scope

1.2 Applicability

1.3 Claiming mobileOK conformance

1.4 Who is mobileOK for?

2 Conformance

2.1 Validity of the Tests

2.2 Testing Outcomes

2.3 Conduct of Tests

2.4 Testing Parameters

2.4.1 HTTP Request

2.4.2 Style Information

3 mobileOK Basic Tests

3.1 AUTO_REFRESH (partial) and REDIRECTION

3.2 CHARACTER_ENCODING_SUPPORT and CHARACTER_ENCODING_USE

3.3 CONTENT_FORMAT_SUPPORT

3.4 DEFAULT_INPUT_MODE

3.5 EXTERNAL_RESOURCES

3.6 GRAPHICS_FOR_SPACING

3.7 IMAGE_MAPS

3.8 IMAGES_RESIZING and IMAGES_SPECIFY_SIZE

3.9 LARGE_GRAPHICS

3.10 LINK_TARGET_FORMAT

3.11 MEASURES

3.12 <meta> element consistency with HTTP header

3.13 MINIMIZE

3.14 NO_FRAMES

3.15 NON-TEXT_ALTERNATIVES (partial)

3.16 OBJECTS_OR_SCRIPT (partial)

3.17 PAGE_SIZE_LIMIT

3.18 PAGE_TITLE (partial)

3.19 POP_UPS

3.20 PROVIDE_DEFAULTS (partial)

3.21 SCROLLING (partial)

3.22 STYLE_SHEETS_SUPPORT (partial)

3.23 STYLE_SHEETS_USE

3.24 TABLES_ALTERNATIVES

3.25 TABLES_LAYOUT (partial)

3.26 TABLES_NESTED

3.27 VALID_MARKUP

A Acknowledgements (Non-Normative)

B References (Non-Normative)

C Best Practices' Relation to mobileOK Tests (Non-Normative)

3.12 `<meta>` element consistency with HTTP header