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Introduce an id, and change navigationId to point to it.
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@clelland
clelland committed Oct 6, 2023
1 parent 8e34f8f commit 771922d
Showing 1 changed file with 46 additions and 24 deletions.
70 changes: 46 additions & 24 deletions index.html
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Original file line number Diff line number Diff line change
Expand Up @@ -47,7 +47,7 @@
"check-punctuation": true,
},
doJsonLd: true,
xref: ["hr-time-3", "infra", "html", "dom", 'ecmascript'],
xref: ["hr-time-3", "infra", "html", "dom"],
mdn: "performance-timeline",
};
</script>
Expand Down Expand Up @@ -246,6 +246,9 @@ <h2><dfn>Performance Timeline</dfn></h2>
<li>An integer <dfn>dropped entries count</dfn> that is initially 0.</li>
</ul>
</li>
<li>An integer <dfn>last performance entry id</dfn> that is initially set
to a random integer between 100 and 10000.
</li>
</ul>
<p>Each <a>Document</a> has:</p>
<ul>
Expand Down Expand Up @@ -310,14 +313,19 @@ <h2>The <dfn>PerformanceEntry</dfn> interface</h2>
<pre class='idl'>
[Exposed=(Window,Worker)]
interface PerformanceEntry {
readonly attribute unsigned long long id;
readonly attribute DOMString name;
readonly attribute DOMString entryType;
readonly attribute DOMHighResTimeStamp startTime;
readonly attribute DOMHighResTimeStamp duration;
readonly attribute DOMString navigationId;
readonly attribute unsigned long long navigationId;
[Default] object toJSON();
};</pre>
<dl>
<dt><dfn>id</dfn></dt>
<dd>
This attribute MUST return the value of <a>this</a>'s <a>id</a>.
</dd>
<dt><dfn>name</dfn></dt>
<dd>
This attribute MUST return an identifier for this
Expand Down Expand Up @@ -674,6 +682,12 @@ <h2>Queue a <code>PerformanceEntry</code></h2>
<p>To <dfn class="export">queue a PerformanceEntry</dfn> (<var>newEntry</var>), run
these steps:</p>
<ol>
<li>If <var>newEntry</var>'s {{PerformanceEntry/id}} is unset:
<ol>
<li>Let <var>id</var> be the result of running <a>generate an id</a> for <var>newEntry</var>.</li>
<li>Set <var>newEntry</var>'s {{PerformanceEntry/id}} to <var>id</var>.</li>
</ol>
</li>
<li>Let <var>interested observers</var> be an initially empty set of
<a>PerformanceObserver</a> objects.
</li>
Expand All @@ -687,7 +701,7 @@ <h2>Queue a <code>PerformanceEntry</code></h2>
<ol>
<li>Set <var>newEntry</var>'s <a
data-lt="PerformanceEntry.navigationId">navigationId</a> to the value of
<var>relevantGlobal</var>'s [=associated document=]'s [=most recent navigation=]'s {{PerformanceEntry/navigationId}}.</li>
<var>relevantGlobal</var>'s [=associated document=]'s [=most recent navigation=]'s {{PerformanceEntry/id}}.</li>
</ol>
</li>
<li>Otherwise, set <var>newEntry</var>'s <a
Expand Down Expand Up @@ -742,11 +756,12 @@ <h2>Queue a navigation <code>PerformanceEntry</code></h2>
<p>To <dfn class="export">queue a navigation PerformanceEntry</dfn> (<var>newEntry</var>), run
these steps:</p>
<ol>
<li>Let <var>navigationId</var> be the result of running <a>generate a navigationId</a> for <var>newEntry</var>.</li>
<li>Let <var>id</var> be the result of running <a>generate an id</a> for <var>newEntry</var>.</li>
<li>Let <var>relevantGlobal</var> be <var>newEntry</var>'s <a>relevant
global object</a>.
</li>
<li>Set <var>newEntry</var>'s {{PerformanceEntry/navigationId}} to <var>navigationId</var>.</li>
<li>Set <var>newEntry</var>'s {{PerformanceEntry/id}} to <var>id</var>.</li>
<li>Set <var>newEntry</var>'s {{PerformanceEntry/navigationId}} to <var>id</var>.</li>
<li>If <var>relevantGlobal</var> has an [=associated document=]:
<ol>
<li>Set <var>relevantGlobal</var>'s [=associated document=]'s [=most recent navigation=] to <var>newEntry</var>.</li>
Expand Down Expand Up @@ -925,28 +940,26 @@ <h2>Determine if a performance entry buffer is full</h2>
</ol>
</section>
<section data-link-for="PerformanceEntry">
<h2>Generate a navigationId</h2>
<p>When asked to <dfn class="export">generate a navigationId</dfn> for a
<h2>Generate a Performance Entry id</h2>
<p>When asked to <dfn class="export">generate an id</dfn> for a
<a>PerformanceEntry</a> <var>entry</a>, run the following steps:</p>
<ol>
<li>Let <var>type</var> be <var>entry</var>'s <a>entryType</a>.</li>
<li>Let <var>startTime</var> be <var>entry</var>'s <a>startTime</a>.
<li>Let <var>timeString</var> be the result of calling
{{Number/toString(radix)}}(<var>startTime</var>, 10).
</li>
<li>If <var>timeString</var> contains the code point U+002E FULL STOP:
<ol>
<li><a>Assert</a>: <var>timeString</var> contains only one instance
of U+002E FULL STOP.</li>
<li><a>Assert</a>: <var>timeString</var> contains at least one code
point following the U+002E FULL STOP code point.</li>
<li>Truncate <var>timeString</var> after the first code point
following the U+002E FULL STOP code point.</li>
</ol>
</li>
<li>Return the [=string/concatenation=] of « <var>type</var>,
<var>timeString</var> » using U+002D HYPHEN-MINUS.</li>
<li>Let <var>relevantGlobal</var> be <var>entry</var>'s <a>relevant
global object</a>.
<li>Increase <var>relevantGlobal</var>'s <a>last performance entry
id</a> by a small number chosen by the user agent.</li>
<li>Return <var>relevantGlobal</var>'s <a>last performance entry id</a>.
</ol>
<p>A user agent may choose to increase the <a>last performance entry
id</a>it by a small random integer every time. A user agent must not pick
a single global random integer and increase the <a>last performance entry
id</a> of all global objects by that amount because this could introduce
cross origin leaks.
</p>
<p class="note">The <a>last performance entry id</a> has an initial random
value, and is increased by a small number chosen by the user agent instead
of 1 to discourage developers from considering it as a counter of the
number of entries that have been generated in the web application.</p>
</section>
</section>
<section id="privacy">
Expand All @@ -956,6 +969,15 @@ <h3>Privacy Considerations</h3>
refer to [[HR-TIME-3]] for privacy considerations of exposing high-resoluting timing
information. Each new specification introducing new performance entries should have its own
privacy considerations as well.</p>
<p>The <a>last performance entry id</a> is deliberately initialized to a
random value, and is incremented by another small value every time a new
{{PerformanceEntry}} is queued. User agents may choose to use a consistent
increment for all users, or may pick a different increment for each
<a>global object</a>, or may choose a new random increment for each
{{PerformanceEntry}}. However, in order to prevent cross-origin leaks, and
ensure that this does not enable fingerprinting, user agents must not just
pick a unique random integer, and use it as a consistent increment for all
{{PerformanceEntry}} objects across all <a>global objects</a>.
</section>
<section id="security">
<h3>Security Considerations</h3>
Expand Down

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