W3C mobileOK Basic Tests 1.0 (original) (raw)
1 Introduction
mobileOK Basic is a scheme for assessing whether Web resources (Web content) can be delivered in a manner that is conformant with Mobile Web Best Practices [Best Practices] to a simple and largely hypothetical mobile user agent, the Default Delivery Context.
This document describes W3C mobileOK Basic tests for delivered content, and describes how to emulate the DDC when requesting that content.
The intention of mobileOK is to help catalyze development of Web content that provides a functional user experience in a mobile context. It is not a test for browsers, user agents or mobile devices, and is not intended to imply anything about the way these should behave.
mobileOK does not imply endorsement or suitability of content. For example, it must not be assumed that a claim that a resource is mobileOK conformant implies that it is of higher informational value, is more reliable, more trustworthy or is more appropriate for children than any other resource.
1.1 Scope
1.1.2 Out of Scope
Some Best Practices, like TESTING, are advisable but do not meaningfully translate into concrete tests.
The tests assess whether the content can be provided in a way that achieves basic usability, efficiency, and interoperability with mobile devices. The tests should not be understood to assess thoroughly whether the content has been well-designed for mobile devices.
2 Conformance
2.4 Conduct of Tests
2.4.3 HTTP Request
The following HTTP request headers inform the server that it should deliver content that is compatible with the Default Delivery Context.
- Use the HTTP
GET
method when making requests, except for3.10 LINK_TARGET_FORMAT where theHEAD
method may be used (See 2.4.8 Linked Resources for a discussion of thePOST
method). - Include a
User-Agent
header which starts exactly as follows (indicating the Default Delivery Context, and which may be extended in accordance with [RFC 2616] Section 14.43, User-Agent Header) :
User-Agent: W3C-mobileOK/DDC-1.0 (see 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 by sending exactly this header:
Accept: application/xhtml+xml,text/html;q=0.1,application/vnd.wap.xhtml+xml;q=0.1,text/css,image/jpeg,image/gif - Include an
Accept-Charset
header indicating that only UTF-8 is accepted by sending exactly this header: - Do not include cookie related headers.
- Include authentication information if required (see 2.4.4 HTTP Response). Once authentication information has been included in a request, subsequent requests for the same realmmust include authentication information as described in Section 2 and under "domain" in Section 3.2.1 of[RFC 2617].
- Implementations must support URIs with both
http
andhttps
scheme components.
Note:
As noted under 2.4.7 Included Resources and 2.4.8 Linked Resources the URIs that are relevant to mobileOK are those that, when represented in an absolute form, have either thehttp
or thehttps
scheme. Requests should not be made for URIs with schemes other thanhttp
andhttps
.
2.4.4 HTTP Response
If an HTTP request does not result in a valid HTTP response (because of network-level error, DNS resolution error, or non-HTTP response), FAIL
If the HTTP status indicates redirection (status code 3xx):
Do not carry out tests on the response
If the response relates to a request for the resource under test, or any of its Included Resources (see 2.4.7 Included Resources):
Include the size of the response in the "total size" as described under 3.16 PAGE_SIZE_LIMIT
Include this response under the count as described under3.6 EXTERNAL_RESOURCES
If there is no HTTP Location
header, FAIL.
If the URI identified by the HTTPLocation
header is a relative URI, create an absolute URI by combining the value of the Location
header with the absolute URI of the request to which this is a response, warn
If the resulting URI is not a URI with the schemehttp
or https
, FAIL.
Re-request the resource using the URI formulated above.
If the HTTP status indicates that authentication is required (e.g. status code 401):
If the response relates to a request for the resource under test, or any of its Included Resources (see 2.4.7 Included Resources):
If authentication information was supplied in the HTTP request (i.e. authentication failed) or if no authentication information is available, FAIL
Carry out tests on the response
Include the size of the response in the "total size" as described under 3.16 PAGE_SIZE_LIMIT
Include this response under the count as described under3.6 EXTERNAL_RESOURCES
Re-request the resource using authentication information
If the response relates to a request for a linked resource (see 2.4.8 Linked Resources):
Continue with the test (see 3.10 LINK_TARGET_FORMAT, i.e. do not re-request the resource with authentication information), warn
If the HTTP status code is 404 or 5xx
If the response relates to a request for the resource under test, continue with tests on the response and warn
If the response relates to a request for a linked resource (see 2.4.8 Linked Resources), continue with the test (see 3.10 LINK_TARGET_FORMAT) and warn
Otherwise (i.e. for Included Resources), FAIL
If the HTTP status represents failure (4xx), other than 404, a request for authentication (e.g. 401) or a 406 when carrying out the 3.15.1 Object Element Processing Rule, FAIL
2.4.6 CSS Style
Some tests refer to "CSS Style" information. Assemble the CSS Style by using the contents of:
- the
style
attribute of any element (use of thestyle
attribute is deprecated in XHTML Basic 1.1[XHTML Basic 1.1]) style
elements whosetype
attribute is "text/css", and whosemedia
attribute is either not present or is present and contains values "all" or "handheld" (case-insensitive).- resources linked via
link
elements andxml-stylesheet
processing instructions, where:- the
rel
attribute contains "stylesheet" but not "alternate" (case-insensitive) - the
charset
attribute is either not present or is present with value "UTF-8" (case-insensitive) - the
type
attribute is either not present or is present with value "text/css" - the
media
attribute is either not present or is present and contains value "all" or "handheld" (case-insensitive).
Note:
In the case ofxml-stylesheet
processing instructions, attribute in this section refers to_pseudo-attribute_.
- the
- resources linked by CSS
@import
at-rules whose presentation media list is either not present or is present and contains the value "all" or "handheld"
In the course of assembling the CSS Style use only those CSS rulesets that are not restricted as to their presentation media type or whose presentation media type list contains "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 first in dictionary order.
3.1 AUTO_REFRESH and REDIRECTION
This test does not determine whether the user is able to opt out of refresh.
If a meta
element is present withhttp-equiv
attribute value of "refresh",
If the URI specified as part of the content
attribute is not the current resource's URI, FAIL
Else, warn
If a Refresh
HTTP header is present,
If the URI specified in the header value is not the current resource's URI, FAIL
Else, warn
3.2 CACHING
The purpose of the test is to alert providers to the fact that their content may not be cached, if it would be beneficial to do so.
Note:
Where both a meta
element with http-equiv
attribute and the corresponding HTTP header are found, the value of the HTTP headermust be used - see also note under 2.4.5 Meta http-equiv Elements.
If the HTTP response contains neither anExpires
nor Cache-Control
header
If no meta http-equiv
element is present, referring to those headers, FAIL
Continue the test using the value from the meta
content
attribute as though it were specified in the appropriate header, warn
If a Cache-Control
HTTP header is present and contains value "no-cache", or contains value "max-age=0", warn
If a Pragma
HTTP header is present and contains value "no-cache", warn
If an Expires
and Date
HTTP header are present, and the Expires
header specifies a date which is not later than what the Date
header specifies, warn
If any cache related header contains an invalid value, warn
If the HTTP response contains a Last-Modified
header,
Request the same URI again, adding anIf-Modified-Since
request header whose value matches that of the Last-Modified
response header
If the HTTP response contains a Last-Modified
header and its value is again the same, and the HTTP response status is not 304 (Not Modified), warn
If the HTTP response contains an ETag
header,
Request the same URI again, adding anIf-None-Match
request header whose value matches that of theETag
response header
If the HTTP response contains an ETag
header and its value is again the same, and the HTTP response status is not 304 (Not Modified), warn
3.3 CHARACTER_ENCODING_SUPPORTand CHARACTER_ENCODING_USE
The DDC is defined to support only UTF-8 encoding, and hence this test fails if a resource is not encoded in UTF-8. The test does not require that resource always be encoded in UTF-8; the test merely checks that the resource is available in UTF-8 encoding, if requested. Resources may be represented using other encodings where appropriate. This test verifies that a DDC-like device which only accepts UTF-8 encoding may access the resource in UTF-8 encoding.
This test requires that character encoding is explicitly specified and recognizes the following methods of specification:
- HTTP
Content-Type
header
application/xhtml+xml_; charset=UTF-8_ - XML declaration
meta
element that is the first child of the document'shead
element, and whosehttp-equiv
attribute is "Content-Type", and whosecontent
attribute specifies a character encoding
... ...
If the HTTP Content-Type
header specifies a character encoding other than UTF-8, FAIL
If the HTTP Content-Type
header does not specify a character encoding:
If there is no XML declaration, or UTF-8 character encoding is not specified in the XML declaration, FAIL
If the HTTP Content-Type
header specifies an Internet media type starting with "text/":
If there is no meta
element withhttp-equiv
attribute that specifies UTF-8 character encoding, FAIL
If character encoding is specified in more than one way, and not all values are the same, FAIL
If the document is not valid UTF-8 (see 2.4.9 Validity), FAIL
For each resource specified by 2.4.7 Included Resources:
Request the resource
If the HTTP Content-Type
header value of the response starts with "text/" but does not specify UTF-8 character encoding, warn
3.4 CONTENT_FORMAT_SUPPORT andVALID_MARKUP
Note:
In the following, an "html document" is a document that has "html" as its root element.
Note:
In the following, "regardless of its stated DOCTYPE
" means that when assessing validity against the XHTML Basic 1.1 and XHTML MP 1.2 DTDs this may be carried out by inserting a DOCTYPE
if none is present, or by replacing the given DOCTYPE
with the appropriateDOCTYPE
for the DTD under test.
Note:
In the following, "a known XHTML version" means XHTML Basic 1.0, XHTML Basic 1.1, XHTML-MP 1.0, XHTML-MP 1.1 or XHTML-MP 1.2.
If the document's Internet media type, as specified in the HTTP response Content-Type
header, is not "application/xhtml+xml", "application/vnd.wap.xhtml+xml", or "text/html", FAIL
If the document's Internet media type is "text/html" or "application/vnd.wap.xhtml+xml", warn
If the document does not contain a DOCTYPE
declaration, FAIL
If the document is not an HTML document, FAIL
If the DOCTYPE
is not an XMLDOCTYPE
, warn
If the document is an HTML document and it has an XML DOCTYPE
:
If the document does not declare the html namespace on itshtml
root element, FAIL
If the DOCTYPE
refers to a known XHTML version, validate against thatDOCTYPE
and if invalid, warn
Otherwise (if the DOCTYPE
is not known), warn
If (regardless of its stated DOCTYPE) the document does not validate against the XHTML Basic 1.1 DTD:
If (regardless of its stated DOCTYPE) it does not validate against the XHTML-MP 1.2 DTD, FAIL
For each Included Resource (see 2.4.7 Included Resources):
If the response specifies an Internet media type that is not "text/css", "image/jpeg" or "image/gif", FAIL
If an image is required (see also 3.15 OBJECTS_OR_SCRIPT) and the response specifies an Internet media type that is not "image/jpeg" or "image/gif", FAIL
If the Internet media type is "image/gif" or "image/jpeg", and the resource is not valid (see 2.4.9 Validity), FAIL
If a style sheet is required and the response specifies an Internet media type that is not "text/css", FAIL
If the Internet media type is "text/css" and the content is not valid CSS (see 2.4.9 Validity), FAIL
3.5 DEFAULT_INPUT_MODE
Note:
inputmode
is part of [XHTML Basic 1.1].
For each input
element with attributetype
whose value is "text" or "password" or whose type
attribute is missing:
If the element's inputmode
attribute is invalid according to Section 5.2 User Agent Behavior of XHTML Basic 1.1 [XHTML Basic 1.1], FAIL
If the element's value
attribute is missing or empty, and an inputmode
attribute is not present, warn
For each textarea
element:
If the element's inputmode
attribute is invalid according to Section 5.2 User Agent Behavior of XHTML Basic 1.1 [XHTML Basic 1.1], FAIL
If the element is empty and an inputmode
attribute is not present, warn
3.6 EXTERNAL_RESOURCES
Retrieve the resource under test, and add the number of retrievals required to obtain the resource (see 2.4.4 HTTP Response) to a running total.
For each unique Included Resource, as defined in 2.4.7 Included Resources:
Request the referenced resource
Add the number of HTTP requests that are required to retrieve the resource (see 2.4.4 HTTP Response) to the running total. Include in the count only those objects retrieved under the 3.15.1 Object Element Processing Rule whose type
attribute is not specified, and those whose content type is either "image/jpeg" or "image/gif" irrespective of whether the type
attribute is specified.
If the total exceeds 10, warn
If this total exceeds 20, FAIL
3.7 GRAPHICS_FOR_SPACING
The intent of this Best Practice is to avoid using transparent images for spacing. However, small transparent images are often used in e-commerce sites for user tracking purposes. The practice is common enough, and possibly vital enough to the business interests of mobile sites, that it is undesirable to fail sites that use such small transparent images. Therefore this machine-testable test merely warns about the presence of small (at most 2x2) transparent images and FAILs larger ones. It is believed that few if any sites would use transparent images of any significant size for tracking.
For each img
element andobject
element which is an Included Resource (see 2.4.7 Included Resources):
If all pixels are transparent,
If image height and width are both less than or equal to 2 pixels, warn
If either dimension exceeds 2 pixels, FAIL
If more than one image with all transparent pixels is present, warn
3.8 IMAGE_MAPS
If an input
element with type
attribute set to "image" is present, FAIL
For each img
element and object
element which is an Included Resource (see 2.4.7 Included Resources):
If a usemap
attribute is present, FAIL
If an ismap
attribute is present, FAIL
3.9 IMAGES_RESIZING and IMAGES_SPECIFY_SIZE
Note:
The height
and width
HTML attributes specify pixels when they are used as a number. No unit is specified.
For each img
element andobject
element which is an Included Resource (see 2.4.7 Included Resources):
If the height
or width
attribute are missing, FAIL
If the height
or width
attribute do not specify a size in pixels, FAIL
If the value specified by either the height or width attribute is greater than the corresponding dimension of the image, warn
If the value specified by either the height or width attribute is less than the corresponding dimension of the image, FAIL
3.10 LINK_TARGET_FORMAT
Note:
404 and 5xx HTTP status do not result in failure when conducting this test.
Note:
The document body of linked resources is not examined.
For each linked resource, as defined in 2.4.8 Linked Resources:
Request the resource
If the Content-Type
header value of the HTTP response is not one of the Internet media types listed in theAccept
header in 2.4.3 HTTP Request, warn
If the Content-Type
header value of the HTTP response does not specify a charset
parameter, or does but it is not consistent with the value of the Accept-Charset
header in 2.4.3 HTTP Request, warn
For each document internal reference (links in the document under test that refer to the document itself):
If there is no target for the reference or it is invalid (e.g. '#'), warn
3.11 MEASURES
Note:
The intrinsic size of images must be specified as attributes of theimg
element and not as CSS properties (see 3.9 IMAGES_RESIZING and IMAGES_SPECIFY_SIZE)
Note:
Only CSS Level 1 properties are considered in this test.
For each CSS Level 1 property in the CSS Style (see 2.4.6 CSS Style) whose value is a numeric measure of length stated together with a unit:
If the value is non-zero and the unit is not "em" or "ex" (and the value is not a percentage), and the property is not a margin, border or padding box property, FAIL
3.12 MINIMIZE
Note:
Extraneous white space characters in script and in CSS are not considered in this test. Such an extension may be considered in a future revision of this specification.
Count number of white space characters (see 2.4.10 White Space) in a sequence of more than one white space character (not counting the first), which exist outside of apre
, style
, script
element, or XML comment.
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
3.13 NO_FRAMES
If the document contains a frame
,frameset
or iframe
element, FAIL
3.14 NON-TEXT_ALTERNATIVES
This test does not determine whether the alternative text is meaningful.
Note:
An empty alt
attribute is acceptable and signifies that there is no meaningful textual alternative, for example for images that are purely decorative.
For each img
element:
If an alt
attribute is not present or contains only white space, FAIL
3.15 OBJECTS_OR_SCRIPT
This test does not determine whether the document is still usable without the objects or scripts.
If a script
element is present, warn
If any element has an "intrinsic event" attribute (currently onload
, onunload
,onclick
, ondblclick
, onmousedown
,onmouseup
, onmouseover
,onmousemove
, onmouseout
, onfocus
,onblur
, onkeypress
, onkeydown
,onkeyup
, onsubmit
, onreset
,onselect
, onchange
), warn
For each a
and link
element:
If the value of the href
attribute begins with the "javascript:" scheme, FAIL
If an applet
element is present, FAIL
Set the context to the root element and apply the Object Element Processing Rule
3.15.1 Object Element Processing Rule
Note:
A warning is issued when the Internet media type indicated by the type
attribute is not compatible with the Default Delivery Context because some user agents do not take into account the type
attribute of object
elements and this may cause the user agent to retrieve large incompatible objects with consequences to performance and cost.
Note:
An HTTP 406 status on retrieval of a resource referenced by an object element does not constitute a FAIL.
3.16 PAGE_SIZE_LIMIT
Retrieve the document under test, if its size (excluding any redirections discussed under 2.4.4 HTTP Response) exceeds 10 kilobytes, FAIL
Add to a running total (total size) the size of all the HTTP response bodies that are required to retrieve the document under test (2.4.4 HTTP Response).
For each unique Included Resource, as defined in 2.4.7 Included Resources:
Add the size of all the response bodies that are required to retrieve the resource (see 2.4.4 HTTP Response) to the running total. Include in the total only those objects retrieved under the 3.15.1 Object Element Processing Rule whose type
attribute is not specified, and those whose Internet media type as indicated by the Content-Type
HTTP header is either "image/jpeg" or "image/gif" irrespective of whether the type
attribute is specified.
If the total exceeds 20 kilobytes, FAIL
Note:
In the case of resources that are referenced more than once in the document under test, and where, as discussed under 2.4.7 Included Resources, they are cached, it is the initial retrieval of that resource (as determined by the first reference in document order) that counts towards the total.
Note:
Where the 3.15.1 Object Element Processing Rule yields a resource that is found to be cached, objects that must be assessed in the course of yielding the cached resource count towards the total.
3.17 PAGE_TITLE
This test does not determine whether the title is meaningful.
If a title
element is not present in thehead
element, or is empty, or contains only white space (see 2.4.10 White Space), FAIL
3.18 POP_UPS
For each a
, link
,form
, and base
element:
If a target
attribute is present,
If its value is not one of "_self", "_parent", or "_top", FAIL
3.19 PROVIDE_DEFAULTS
For each radio button group within a form
element (input
elements with type
"radio" that share the same name
attribute value):
Check that exactly one input
element within this group has its checked
attribute set to "checked", and if this is not the case, warn
For each select
element:
If there is no nested option
element whoseselected
attribute is set to "selected",warn
If there is more than one option
element whose selected
attribute is set to "selected", and the multiple
attribute is not set to "multiple", warn
3.21 STYLE_SHEETS_USE
This test looks for elements in the Text Extension module defined by [XHTML Modularization], some of which are not supported in XHTML Basic [XHTML Basic 1.1]. It also looks for commonly-used elements and attributes that were deprecated in HTML 4, and are not supported, or are deprecated, in XHTML Basic.
Note:
This test does not require that any CSS Style is used, since in some cases, no presentation information is required at all (for example, a simple page of text).
If the document contains any basefont
,bdo
, center
, del
,dir
, font
, ins
, menu
,s
, strike
or u
elements, FAIL
If the document contains any b
,big
, i
, small
, sub
,sup
or tt
elements, warn
If any element has a style
attribute, warn
If all styles are restricted to presentation media types other than "handheld" or "all" by means of @media
at-rules, warn
If the CSS Style contains at-rules (other than the@media
at-rule, and the presentation media type list of the@import
at-rule), properties, or values that are not recognized as being specified in CSS Level 1, or if the value of a recognized CSS Level 1 property is incompatible with the property, warn
3.23 TABLES_LAYOUT
This test does not catch all cases where tables are used for layout purposes.
For each table
element:
If it contains at most one tr
element, FAIL
If no tr
element contains more than onetd
element, FAIL
For each nested td
element:
If the element contains only an image (or equivalent object) whose actual dimensions are 2x2 or less,FAIL