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Use StructuredSerialize/StructuredDeserialize. For #170
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inexorabletash committed Mar 23, 2017
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106 changes: 80 additions & 26 deletions index.bs
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Expand Up @@ -28,6 +28,12 @@ spec: html; urlPrefix: https://html.spec.whatwg.org/multipage/
urlPrefix: dom.html
type: interface
text: Document; url: document
urlPrefix: infrastructure.html
type: abstract-op
text: StructuredSerialize; url: structuredserialize
text: StructuredDeserialize; url: structureddeserialize
type: dfn
text: serializable objects; url: serializable-objects
spec: ecma262; urlPrefix: https://tc39.github.io/ecma262/
type: dfn
url: sec-algorithm-conventions
Expand Down Expand Up @@ -55,6 +61,7 @@ spec: ecma262; urlPrefix: https://tc39.github.io/ecma262/
text: Promise; url: sec-promise-objects
text: Realm; url: realm
text: current Realm; url: current-realm
text: Record; url: sec-list-and-record-specification-type
spec: webidl; urlPrefix: https://heycam.github.io/webidl/
type: dfn
text: sequence<DOMString>; url: idl-sequence
Expand Down Expand Up @@ -556,13 +563,16 @@ transaction=] is running.
<!-- ============================================================ -->

Each record is associated with a <dfn>value</dfn>. User agents must
support any [=cloneable object=]. This includes simple types
support any [=serializable object=]. This includes simple types
such as [=String=] primitive values and [=Date=] objects as well as
[=Object=] and [=Array=] instances, {{File}} objects, {{Blob}}
objects, {{ImageData}} objects, and so on. Record [=/values=] are
stored and retrieved by value rather than by reference; later changes
to a value have no effect on the record stored in the database.

Record [=/values=] are [=/Records=] output by the
<a abstract-op>StructuredSerialize</a> operation.


<!-- ============================================================ -->
<h3 id=key-construct>Keys</h3>
Expand Down Expand Up @@ -773,7 +783,7 @@ from a [=/value=]. A <dfn>valid key path</dfn> is one of:
</aside>

[=/Key path=] values can only be accessed from properties explicitly
copied by <a abstract-op>StructuredClone</a>, as well as the
copied by <a abstract-op>StructuredSerialize</a>, as well as the
following type-specific properties:

<table class=props>
Expand Down Expand Up @@ -2952,9 +2962,17 @@ when invoked, must run these steps:

9. Let |targetRealm| be a user-agent defined [=Realm=].

10. Let |clone| be <a abstract-op>StructuredClone</a>(|value|, |targetRealm|).
10. Let |clone| be a [=clone=] of |value| in |targetRealm|.
Rethrow any exceptions.

<details class=note>
<summary>Why create a copy of the value?</summary>
The value must be serialized when stored. Treating it as a copy
here allows other algorithms in this specification to treat it as
an ECMAScript value, but implementations may optimize this
if the difference in behavior is not observable.
</details>

11. If |store| uses [=in-line keys=], run these substeps:

1. Let |kpk| be the result of running the steps to [=extract a
Expand Down Expand Up @@ -3023,9 +3041,17 @@ when invoked, must run these steps:

9. Let |targetRealm| be a user-agent defined [=Realm=].

10. Let |clone| be <a abstract-op>StructuredClone</a>(|value|, |targetRealm|).
10. Let |clone| be a [=clone=] of |value| in |targetRealm|.
Rethrow any exceptions.

<details class=note>
<summary>Why create a copy of the value?</summary>
The value must be serialized when stored. Treating it as a copy
here allows other algorithms in this specification to treat it as
an ECMAScript value, but implementations may optimize this
if the difference in behavior is not observable.
</details>

11. If |store| uses [=in-line keys=], run these substeps:

1. Let |kpk| be the result of running the steps to [=extract a
Expand Down Expand Up @@ -4887,9 +4913,17 @@ invoked, must run these steps:

7. Let |targetRealm| be a user-agent defined [=Realm=].

8. Let |clone| be <a abstract-op>StructuredClone</a>(|value|, |targetRealm|).
8. Let |clone| be a [=clone=] of |value| in |targetRealm|.
Rethrow any exceptions.

<details class=note>
<summary>Why create a copy of the value?</summary>
The value must be serialized when stored. Treating it as a copy
here allows other algorithms in this specification to treat it as
an ECMAScript value, but implementations may optimize this
if the difference in behavior is not observable.
</details>

9. If the [=effective object store=] of this cursor uses [=in-line
keys=], run these substeps:

Expand Down Expand Up @@ -5758,6 +5792,23 @@ the implementation must run the following steps:

</div>

<!-- ============================================================ -->
<h3 id=clone-value>Clone a value</h3>
<!-- ============================================================ -->

<div class=algorithm>

To make a <dfn>clone</dfn> of |value| in |targetRealm|,
the implementation must run the following steps:

1. Let |serialized| be [=?=] <a abstract-op>StructuredSerialize</a>(|value|).

2. Let |clone| be [=?=] <a abstract-op>StructuredDeserialize</a>(|serialized|, |targetRealm|).

3. Return |clone|.

</div>


<!-- ============================================================ -->
<h2 id=database-operations>Database operations</h2>
Expand All @@ -5769,9 +5820,10 @@ These operations are run by the steps to [=asynchronously execute
a request=].

<aside class=note>
Invocations of <a abstract-op>StructuredClone</a>() in the operation steps below
can be asserted not to throw (as indicated by the [=!=] prefix)
because they operate only on previously cloned data.
Invocations of <a abstract-op>StructuredDeserialize</a>() in the operation
steps below can be asserted not to throw (as indicated by the [=!=] prefix)
because they operate only on previous output of
<a abstract-op>StructuredSerialize</a>().
</aside>

<!-- ============================================================ -->
Expand Down Expand Up @@ -5812,7 +5864,8 @@ follows.
to=] |key|, then remove the [=object-store/record=] from |store| using the
steps to [=delete records from an object store=].

4. Store a record in |store| containing |key| as its key and |value|
4. Store a record in |store| containing |key| as its key and
<a abstract-op>StructuredSerialize</a>(|value|)
as its value. The record is stored in the object store's
[=object-store/list of records=] such that the list is sorted
according to the key of the records in ascending order.
Expand Down Expand Up @@ -5895,9 +5948,9 @@ The steps to <dfn>retrieve a value from an object store</dfn> with

2. If |record| was not found, return undefined.

3. Let |value| be of |record|'s [=/value=].
3. Let |serialized| be of |record|'s [=/value=].

4. Return [=!=] <a abstract-op>StructuredClone</a>(|value|, |targetRealm|).
4. Return [=!=] <a abstract-op>StructuredDeserialize</a>(|serialized|, |targetRealm|).

</div>

Expand All @@ -5917,8 +5970,8 @@ store</dfn> with |targetRealm|, |store|, |range| and optional |count| are as fol

4. For each |record| in |records|, run these substeps:

1. Let |value| be |record|'s [=/value=].
2. Let |entry| be [=!=] <a abstract-op>StructuredClone</a>(|value|, |targetRealm|).
1. Let |serialized| be |record|'s [=/value=].
2. Let |entry| be [=!=] <a abstract-op>StructuredDeserialize</a>(|serialized|, |targetRealm|).
3. Append |entry| to |list|.

5. Return |list| converted to a [=sequence&lt;any&gt;=].
Expand Down Expand Up @@ -5981,9 +6034,9 @@ with |targetRealm|, |index| and |range| are as follows.

2. If |record| was not found, return undefined.

3. Let |value| be |record|'s [=referenced value=].
3. Let |serialized| be |record|'s [=referenced value=].

4. Return [=!=] <a abstract-op>StructuredClone</a>(|value|, |targetRealm|).
4. Return [=!=] <a abstract-op>StructuredDeserialize</a>(|serialized|, |targetRealm|).

</div>

Expand All @@ -6002,8 +6055,8 @@ index</dfn> with |targetRealm|, |index|, |range| and optional |count| are as fol

4. For each |record| in |records|, run these substeps:

1. Let |value| be |record|'s [=referenced value=].
2. Let |entry| be [=!=] <a abstract-op>StructuredClone</a>(|value|, |targetRealm|).
1. Let |serialized| be |record|'s [=referenced value=].
2. Let |entry| be [=!=] <a abstract-op>StructuredDeserialize</a>(|serialized|, |targetRealm|).
3. Append |entry| to |list|.

5. Return |list| converted to a [=sequence&lt;any&gt;=].
Expand Down Expand Up @@ -6277,9 +6330,9 @@ follows.

13. If |cursor|'s [=key only flag=] is unset, run these substeps:

1. Let |value| be |found record|'s [=referenced value=].
1. Let |serialized| be |found record|'s [=referenced value=].
2. Set |cursor|'s [=cursor/value=] to
[=!=] <a abstract-op>StructuredClone</a>(|value|, |targetRealm|)
[=!=] <a abstract-op>StructuredDeserialize</a>(|serialized|, |targetRealm|)

14. Set |cursor|'s [=got value flag=].

Expand Down Expand Up @@ -6424,7 +6477,7 @@ ECMAScript value or failure, or the steps may throw an exception.

<aside class=note>
Assertions can be made in the above steps because this algorithm is
only applied to values that are the output of <a abstract-op>StructuredClone</a>
only applied to values that are the output of <a abstract-op>StructuredDeserialize</a>
and only access "own" properties.
</aside>

Expand Down Expand Up @@ -6472,7 +6525,7 @@ true or false.

<aside class=note>
Assertions can be made in the above steps because this algorithm is
only applied to values that are the output of <a abstract-op>StructuredClone</a>.
only applied to values that are the output of <a abstract-op>StructuredDeserialize</a>.
</aside>

<div class=algorithm>
Expand Down Expand Up @@ -6520,7 +6573,7 @@ as follows. The algorithm takes a |value|, a |key| and a |keyPath|.

<aside class=note>
Assertions can be made in the above steps because this algorithm is
only applied to values that are the output of <a abstract-op>StructuredClone</a>,
only applied to values that are the output of <a abstract-op>StructuredDeserialize</a>,
and the steps to [=check that a key could be injected into a value=] have
been run.
</aside>
Expand Down Expand Up @@ -6953,7 +7006,7 @@ basic serialization concerns, serialized data could encode assumptions
which are not valid in newer versions of the user agent.

A practical example of this is the [=RegExp=] type. The <a
abstract-op>StructuredClone</a> operation allows cloning [=RegExp=]
abstract-op>StructuredSerialize</a> operation allows serializing [=RegExp=]
objects. A typical user agent will compile a regular expression into
native machine instructions, with assumptions about how the input data
is passed and results returned. If this internal state was serialized
Expand Down Expand Up @@ -7060,9 +7113,6 @@ document's Revision History</a>.
* Add non-normative documentation for every method.
(<a href="https://github.com/w3c/IndexedDB/issues/110">bug #110</a>)

* Use [[HTML]]'s <a abstract-op>StructuredClone</a> hook.
(<a href="https://github.com/w3c/IndexedDB/issues/135">bug #135</a>)

* Throw {{SecurityError}} if {{IDBFactory/open()}} or
{{IDBFactory/deleteDatabase()}} is called from an opaque origin.
(<a href="https://github.com/w3c/IndexedDB/issues/148">bug #148</a>)
Expand All @@ -7078,6 +7128,10 @@ document's Revision History</a>.
* Fix handling of edge cases in key generation algorithm.
(<a href="https://github.com/w3c/IndexedDB/issues/147">bug #147</a>)

* Use [[HTML]]'s <a abstract-op>StructuredSerialize</a> and
<a abstract-op>StructuredDeserialize</a> hooks.
(<a href="https://github.com/w3c/IndexedDB/issues/170">bug #170</a>)


<!-- ============================================================ -->
<h2 id=acknowledgements>Acknowledgements</h2>
Expand Down
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