Processing steps for id now removes the fragment #1122
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Update and add examples.
…ment manifest id. Since these are both processed in real time (not from a database) there is no need to exclude fragments here.
If it's just about old data, it should be up to the UA to know whether that old data might exist.
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Hmm... looking at WebKit, it wasn't stripping the fragment etc. I'll need to check what the impact is. |
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| |manifest|["id"] is [=url/equal=] with [=URL serializer/exclude | ||
| fragment|exclude fragment true=] to the [=identity=] of an | ||
| already-installed application, it SHOULD be used as a signal that | ||
| |manifest|["id"] is [=url/equal=] (OPTIONAL: with |
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I think we should remove OPTIONAL... it's a bit confusing. Let's just assume a single model here.
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The purpose of OPTIONAL here is that some UAs may decide not to do it if they are sure the fragments were already stripped. (e.g. if they always strip fragments before writing them into the database, and there never was a time when they didn't do that, or they ran a migration at some point stripping fragments from the database, then they don't need to exclude fragments here).
Not doing so could actually significantly help those clients, for example, they could then compare the hashes of the app IDs rather than having to perform a URL equals operation (which can't be done using a SQL query). This doesn't only affect major browsers, but also any website that indexes apps -- we'd like it to be optional for them so they can simply assume the fragment-removed app IDs are primary keys in their database and do simple lookups. If we made this mandatory, then every entity that indexes apps would need to have no canonical representation of an app ID, and always do the URL equals excluding fragments comparison.
So I did go back and forth on this a bit, but settled on making it OPTIONAL by way of saying "hey, if you've been storing app IDs with their fragments, you probably should exclude fragments when you compare them, but you don't have to do that if you've treated the data properly per the algorithm, and there are significant simplifications to the data model if you don't do this."
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Right, yeah. that seems ok. I wonder if it could be better phrased though the "(OPTIONAL: ...)" looks a bit odd to me. Trying to think of a better way to phrase it.
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@marcoscaceres input needed: I rewrote it as "(with exclude fragments OPTIONALLY set to true)". Is this sufficient to capture RFC 2119's keyword "OPTIONAL"? (Note that Respec doesn't italicize the word "OPTIONALLY" nor does this adverbial form appear in RFC 2119)
Otherwise if it has to exactly use those words, I think the best phrasing is the somewhat verbose: "(the user agent MAY set exclude fragments to true)".
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Hmmm 🤔 let’s go with MAY as I just know people will complain otherwise.
I’ll try to see if I can think of some other phrasing in the future.
Really sorry about all the churn on this!
It should be good to merge otherwise (and as a bonus 🍨, this helped fix two bugs in WebKit, so massive thank you!!!)
Co-authored-by: Marcos Cáceres <marcos@marcosc.com>
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| this manifest is a replacement for the already-installed | ||
| application's manifest, and not a distinct application, even if it is | ||
| served from a different URL than the one seen previously. | ||
| </p> | ||
| <p class="note" title="Exclude fragments for good measure"> |
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| <p class="note" title="Exclude fragments for good measure"> | |
| <p class="note" title="Exclude fragments for comparison"> |
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Rephrased as "is best practice". The "good measure" was supposed to convey the fact that you don't really need to do it, but if you can then just do it anyway to sanitize bad data.
I hope this also conveys that user agents don't have to do this and it can be beneficial not to, because it affords optimizations like hashing.
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| for a matching application. However, since old versions of this spec | ||
| (and, possibly, old user agents) did not remove the [=URL/fragment=] | ||
| from the [=URL=] at parse time, and relied only on | ||
| [=URL/equals/exclude fragments|excluding fragments=] during | ||
| comparisons, there may be historical app data with [=URL/fragments=] | ||
| in the <code>[=manifest/id=]</code>. Therefore, it is best practice for user | ||
| agents to [=URL/equals/exclude fragments=] even when comparing two | ||
| [=URLs=] that should not have any fragments. |
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Removing the use of RFC2119 keywords:
| for a matching application. However, since old versions of this spec | |
| (and, possibly, old user agents) did not remove the [=URL/fragment=] | |
| from the [=URL=] at parse time, and relied only on | |
| [=URL/equals/exclude fragments|excluding fragments=] during | |
| comparisons, there may be historical app data with [=URL/fragments=] | |
| in the <code>[=manifest/id=]</code>. Therefore, it is best practice for user | |
| agents to [=URL/equals/exclude fragments=] even when comparing two | |
| [=URLs=] that should not have any fragments. | |
| for a matching application. However, since old versions of this spec | |
| (and, possibly, old user agents) did not remove the [=URL/fragment=] | |
| from the [=URL=] at parse time, and relied only on | |
| [=URL/equals/exclude fragments|excluding fragments=] during | |
| comparisons, historical app data could include [=URL/fragments=] | |
| in the <code>[=manifest/id=]</code>. Therefore, it is best practice for user | |
| agents to [=URL/equals/exclude fragments=] even when comparing two | |
| [=URLs=] that typically lack fragments. |
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Thanks, good catch! I rephrased these a bit but got rid of the RFC words.
rdar://127864531 https://bugs.webkit.org/show_bug.cgi?id=273991 Reviewed by Sihui Liu. Strips the hash from the id member when parsing the Web Manifest. Part of w3c/manifest#1122 * Source/WebCore/Modules/applicationmanifest/ApplicationManifestParser.cpp: (WebCore::ApplicationManifestParser::parseId): * Tools/TestWebKitAPI/Tests/WebCore/ApplicationManifestParser.cpp: (TEST_F): Canonical link: https://commits.webkit.org/278724@main
https://bugs.webkit.org/show_bug.cgi?id=273989 rdar://127863839 Reviewed by Brady Eidson. Removes the query and fragment components from the scope URL. Part of w3c/manifest#1122 * Source/WebCore/Modules/applicationmanifest/ApplicationManifestParser.cpp: (WebCore::ApplicationManifestParser::parseScope): * Tools/TestWebKitAPI/Tests/WebCore/ApplicationManifestParser.cpp: (TEST_F): Canonical link: https://commits.webkit.org/278795@main
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@marcoscaceres Thanks, I finally got back on this one. Addressed the comments, PTAL. |
SHA: bceb2ee Reason: push, by marcoscaceres Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Closes #1121
This change (choose at least one, delete ones that don't apply):
[Note: This technically changes normative behaviour, but does not break implementations. Any implementation that keeps the fragment and strips it out when comparing ids will behave the same as this. The new behaviour just encourages implementations to keep their local data model clean.]
Commit message:
The canonical id no longer includes the fragment. This was already effectively true (as all comparisons would exclude fragments), but now it makes it true in the processed manifest's canonical id.
Removed or made optional the exclude fragments in the comparisons. Added a lengthy note as to why user agents may still wish to exclude fragments when comparing against potentially old database entries.
Person merging, please make sure that commits are squashed with one of the following as a commit message prefix:
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