The error recovery process is necessary, but is particularly subtle. An
error may occur basically any time some user code is called, which may
leave the internal owl state in an invalid situation.
In this commit, we try to improve Owl behaviour when a crash occurs in a
onMounted hook. Before this commit, it was possible for other component
mounted hooks to be called even though the component was not mounted, or
for willUnmount hooks to be called even though the component was
mounted, but its onMounted hooks had not been called.
All these situations need to be handled when we catch an error. In this
commit, we try to clean more internal state in the error handling code,
to make Owl more consistent.
This commit, add a new configuration on the App: globalValues.
It's a global object of elements available at compilations.
For instance:
```js
const app = new App(SomeComponent, {
globalValues: {
plop: (string: any) => {
steps.push(string);
},
},
});
```
The plop function will be available at the compilation, so it can be
used on the templates :
```xml
<div t-on-click="() => __globals__.plop('click')" class="my-div"/>
```
This commit adds the support for custom directives. To use the
custom directive, an Object of functions needs to be configured on
the owl APP:
```js
new App(..., {
customDirectives: {
test_directive: function (el, value) {
el.setAttribute("t-on-click", value);
return el;
}
}
});
```
The functions will be called when a custom directive with the name of the
function is found. The original element will be replaced with the one
returned by the function.
This :
```xml
<div t-custom-test_directive="click" />
```
will be replace by :
```xml
<div t-on-click="value"/>
```
issue : https://github.com/odoo/owl/issues/1650
If a component onMounted hook causes an error, and an error handler
tries to reinitiate a new correct render, the fiber may be recycled. But
the scheduler removes it from its own set of tasks, so it will be
ignored.
We simply check for this condition before removing it from the tasks
set.
This commit fixes two issues with subroots:
1. creating a subroot create a new component node synchronously. This
would causes issues if the creation was done in the setup of a
component, since in that case, owl would reset the current component to
null right after, which would cause all calls to hooks to fail. This is
fixed by restoring the previous component node right after creating a
root.
2. the destroy method for roots calls the scheduler processTasks.
However, the processTasks method was not safe to reentrant calls,
which would in some cases crashes owl. For example, if a destroy is done
while a new component is mounted, the mount method would be called
twice.
This is fixed by ignoring the processTasks if we are currently
processing tasks. It works because the "for ... of" loop will still
process all new tasks in the current iteration.
In this commit, we extend the owl App class to support multiple sub
roots. This is useful for situations where we want to mount sub
components in non-managed DOM. This is exactly what the Knowledge app is
doing, with mounting views in an html editor.
Currently, this requires some difficult and fragile hacks, and still,
the result is that it is very easy to mix components from the main App
and a SubApp. But Knowledge does not actually care about creating a sub
app. It only needs the possibility to mount sub components in dynamic
places.
closes#1640
Also unnest the handling of `result` via guard clauses, and generate
messages as close as possible to use site, keeping the error
construction itself where it currently is as the goal is specifically
to point back to the *definition* site for the hook function.
Before this commit, when willStart/willUpdateProps took more than
3s, a console.warn was done. In odoo, when a warning is logged
during a test, the test fails and the build is considered as "in
error".
There's a component that loads several resources (sequentially) in
its onWillStart, which *sometimes* takes more than 3s, making
builds fail non deterministically. Since a recent change (which
adds another call in the problematic onWillStart), the warning gets
logged quite often.
A quick fix is necessary, so we change the warn into a log, which
won't make build fail.
We may consider alternatives in the future though:
- add a parameter to onWillStart, to disable the timeout, or to
specify the delay (which is 3s by default)
- do not warn in test mode
Previously, the async hook warning that's emitted when async hooks take
too long to resolve would be emitted even if the component was
destroyed or cancelled. We used to check if the node's fiber was still
the current fiber as a proxy for cancellation, but this is insufficient
in the case where an app might be destroyed.
This commit also wraps the content of some of the warning tests into a
try/finally block so that a failure of these tests doesn't pollute
setTimeout and console.warn and cause other tests to timeout one after
another.
Previously, we had a fixed whitelist for types that were allowed during
props validation. The implementation however supports using arbitrary
classes, and in practice it's desirable to do so, and already done when
not using typescript (when using typescript, it will error if the class
is not whitelisted), eg in Odoo, we use "Element" for the arch in the
standard view props, but this causes all view controllers to fail type
checking because it's not whitelisted.
This commit simply replaces existing constructors by a generic
constructor type, and adds a test with a validation success and a test
with a validation failure.
While Sets have better lookup complexity than arrays, because of the
large constant factors, small arrays can perform better than small sets
when checking for inclusion.
In practice, replacing both of the raw types sets with arrays can
improve performance of reactive-heavy workloads by as much as 30%.
Considering the reactivity code is very hot when rendering data-heavy
components, and the low impact on readability of the fix, the
cost-benefit analysis is clearly in favour of making the fix.
A template set can now obtain a template by calling the function
getTemplate (if any) received in the initial config.
The returned value can be an Element instance, a template string, a
function (i.e. a compiled template), or null. In the last case, owl will
look into the template set rawTemplates object.
For some reason the code of parseXML was duplicated, despite being
exactly the same except for some whitespace. Move it out into a common
utils file.
closes#1569
Previously, having a Function as a type in the static props description
of a component would only work if the component was not the root
component, as the static props description on Component was "any",
whereas the static props description on ComponentConstructor was
"Schema". This meant that static props description on non-root
components was not type-checked, and on root components it was
type-checked only on the mount call.
This commit makes it so that static type description is of type "Schema"
on Component, now causing static props description to be type-checked,
and adds `typeof Function` to the `BaseType` union, which allows
declaring that a component expects a function as a prop.
Closes#1448
With this commit, the templates that are given while instantiating the
App class can be an object with templates not yet parsed (i.e. string,
not Document). This allow to instantiate the App class with templates
that are not yet parsed, and these templates will be parsed only when
needed.
Part of task-id 3601257
`useEffect` type is not compatible with later versions of Typescript.
(I tried with Typescript 5.2, I didn't check which specific
version had the breaking change)
This prevents other projects using owl (such as o-spreadsheet) to
upgrade their own version of Typescript.
`<T extends [...T]>` raises the two following errors:
`Type parameter 'T' has a circular constraint.ts(2313)`
`A rest element type must be an array type.`
Previously, if a reactive was observing the presence of an item in a
set that was originally not present, it would get notified when that
item was "deleted" from the set (even though there was nothing to delete
and the set did not change). The same applied to the key already being
present and then being "added". The same thing occured with Map, both
for presence but also for values (setting a key to the value it was
already set to would notify).
This commit fixes that.
Before this commit, Owl would export the list of apps in a global object
`__OWL_DEVTOOLS__`. However, it is sometimes useful to be able to
access that set, even outside of the devtools (for example, to register
templates in all active apps).
closes#1515
When defining a template with a name that the template set already
contains, we currently always check whether the template is the same and
throw an error when it's not. This is potentially expensive as it can
involve serializing a pretty large XML document. This check is only
supposed to help during development so this commit disables this check
outside dev mode.
Previously, support for iterables was added to t-foreach. The idea was
that anything that you can spread or on which you can use for..of would
be supported. Due to an implementation mistakes, strings, which are
iterable were not supported because we checked that the typeof the
iterable was 'object'.
To fix this, we coerce the iterable to an object and check whether that
coerced value has a Symbol.iterator property, which is what happens
behind the scenes when using for..of or spreading a primitive.
Closes: odoo/owl#1503
Firefox will not serialize the xmlns attributes of node inside
XMLDocuments, see https://bugzilla.mozilla.org/show_bug.cgi?id=175946
it will only output an xmlns attribute if the node being serialized has
a non-null namespaceURI.
When compiling templates, we currently use a special attribute,
"block-ns" to keep track of the namespace, but we do not make use of the
namespace to create the elements that will be serialized to the compiled
block string. This causes a difference in behaviour between Chrome and
Firefox: since we end up with an Element with two attributes: the
block-ns attribute and the xmlns attribute. Chrome will serialize both,
but Firefox will only serialize the block-ns because the Element does
not have a namespaceURI.
To fix this issue, we get rid of the block-ns magic attribute
completely, and use xmlns instead. We also use the namespace when
creating intermediate elements that will be used to create the
serialized block string: the namespace is only used to create the
elements but *not* set as an attribute, as this would cause chrome to
serialize it twice, causing a duplicate attribute error when parsing it
further down the line.
When creating the template element for the block at runtime, the xmlns
attribute is used both as the namespace with which to create the
element, and set as an attribute, this doesn't cause issues when
serializing later because the namespaceURI is never serialized as an
attribute when serializing an HTML document[1], so we avoid the
double-serialization in Chrome, and when doing HTML serialization,
Firefox will correctly serialize the attribute.
It's desirable that the xmlns is set as an attribute to allow users to
use owl to render SVG, and then use the HTML serialization of it as a
SVG even outside the context of an HTML document (eg to generate an SVG
file or an SVG data URL).
[1]: https://w3c.github.io/DOM-Parsing/#xml-serialization
In odoo/owl#1352 we added support for using t-foreach on Map objects,
maps should behave the same as objects where keys are available under
the name specified in t-as and values under that same name with the
suffix `_value`. Unfortunately, because the code for objects was written
in a confusing way (values were stored in a variable named `keys` and
vice versa), the implementation for Map was incorrect and keys and
values were swapped.
This commit fixes that and rewrites the code to be less confusing: keys
are extracted from the variables `k_block` and values from `v_block`,
which swaps the behaviour, and the code to prepare a list from an object
now extracts the keys in `keys` and the values in `values`
Before this commit, the App destroy method would not destroy everything
synchronously. The code scheduled a flush, which is asynchronous, to
finally clean up the task lists, and destroy the cancelled nodes. But
this is not really good for tests: we need a stronger guarantee that
nothing will happen after the destroy.
With this commit, we simply call the processTask method immediately
after destroying the root component, so all cancelled nodes will be
destroyed immediately.
Before this commit, most of the time, components are destroyed when the
virtual dom is patched and a component node is removed. However, since
Owl is asynchronous and a component may take some time to get ready
(with onWillStart), it can happen that a component is created, then
before it is ready, it is recreated. In that case, the initial instance
has to be destroyed.
Before this commit, the destroy operation was done immediately, when we
cancel the current fibers. However, this means that we cannot have a
guarantee between micro task ticks that a component has not been
destroyed in the meantime.
For example, in Odoo, it is common to use the rpc service, which will
throw an error if called by a destroyed component. But because of the
possible destruction of a component at any time, the following code is
unsafe:
async loadSomeData() {
// guaranteed to be called when component is alive
await Promise.resolve();
// however here, component may have been destroyed
this.rpc(...)
}
So, to prevent this issue, we can slightly delay the destroy operation.
It is not entirely trivial, since we need to find a way to neutralize
the component in the meantime. But it seems like performing all that
kind of operation at the "commit" phase (so, the request animation frame
callback) makes sense to me.
So, this commit modifies the code to add a new component status
(cancelled) and use it to cancel components that are waiting to be
destroyed. These components will then be destroyed as soon as the
requestanimation frame starts, before all other dom operations.
Currently the implementation of batched is quite complicated and
difficult to read. This is because this approach tried to block all
calls at the same point and then only let the first one go through, but
an alternative approach is to simply throw away the calls that are made
after the first one has been scheduled. This change makes the
implementation much simpler to understand.
Co-authored-by: Aaron Bohy <aab@odoo.com>
Class attributes are managed in a specific way in owl: they are merged
with existing class attributes, and also, they can be defined in
multiple ways (t-att-class, t-attf-class, t-att=['class', ...] and each
of these can be combined together.
Before this commit, the `t-att` syntax was handled as a normal
attribute, and therefore, would not combine as required with existing
classes.
closes#1453
This commit adapts the behavior of the devtools global hook to get
the toRaw and reactive functions from the __OWL_DEVTOOLS__ variable
instead of the global owl when it is missing. Also adds the functions
to the __OWL_DEVTOOLS__ variable for the former to work.
This allows the devtools to work in environments where owl is loaded
through ES modules.
Also quickly fixes iframes detection update on page reload.
Before this commit, when using a dynamic t-call, it was possible to have
a collision between subcomponent keys. This would cause hard to
understand owl crash, because owl would incorrectly use the same
component instance for two different template location. From
owl point of view, one of these component has to be destroyed and the
other one should be mounted, so a crash would occur.
The fix is to simply properly key sub components.
Before this commit, doing `t-out="null"` would crash, since the
safeOutput function would assume that it is a block, thanks to the fact
that `typeof null === 'object'`.
We handle here the null value just as if it was undefined: it outputs an
empty string.
Before this commit, in some specific situations, owl could skip updating
the DOM, even though it should. Here is what could happen:
- we have a parent component (A) and a child component (B)
- B depends on some reactive props from A
- we update some state that results in A being rendered, and B updated
- before this render is applied to the dom, we update some state again,
which causes A to be rendered again
- however, this new render is such that the B props are now identical,
so it will skip rendering B
- it will then apply the result of the render to the DOM => only A is
updated but B should also be updated!
The problem comes from the fact that Owl committed the props to the
component right after the rendering, to the new props were used in the
props comparison method to decide if B should be updated. This is
incorrect, we should always use the current props to decide what to do,
and only commit them to the component after it has been patched.
In JS, objects are often used as a mapping that gives fast lookup on the
keys, in those cases, the keys themselves are not known in advance, but
the values may have a shape that they're expected to follow. This commit
adds support for a `values` key in schema for objects, which will be
checked against all values in the object during validation.
`onWillPatch`, `onWillUnmount`, `onWillDestroy` are synchronous hooks.
Owl will not wait any promise return by the callback.
Yet, the callback return type includes `Promise<void>`,
which is confusing as one might think it means the hooks is async.
It is common in Owl components to have anonymous function as props.
However, since each rendering create a different (but equivalent)
closure, Owl will consider the props different, so will update the child
component, but this is (often) not necessary.
This commit will help reduce the problem by introducing a new `.alike`
prop suffix, that will let Owl know that each version of that specific
prop should be considered the same, so, will be ignored by the props
comparison code.
closes#1360
Before this commit, the version number was added by the rollup
configuration script. It worked, but it meant that there was no robust
way to access the version number in many case. For example, what if I
have a page with two different version of owl? Or what if one of them
uses the ESM module system, and does not export owl as a global object?
This is not really a big deal, but accessing the version number is
useful for tooling purpose, so this commit makes it possible to read the
version number on each individual App, as a static property.
Previously, refs could get set to null incorrectly, or could stay set
when they shouldn't. This was caused by the fact that singleRefSetter
and multiRefSetters are created on every render, meaning that any render
that did not affect the status of the ref (mounted or not), would
overwrite the previous ref setter, including its closure, causing the
captured `_el` or `count` to be lost. This means that on a subsequent
render that did affect the status of the ref, the singleRefSetter would
consider that it did not set the ref, and so shouldn't unset it, causing
it to incorrectly stay keep the element, while in multiRefSetter, the
opposite problem occured: the count would be 0 on removal, causing it to
believe that it was the first call in the corresponding patch that
affected the ref, when in fact, the closure is already stale, because it
was created from the previous render, and the fresh multiRefSetter from
the latest render may already have been called by an element with that
ref that came earlier in the template.
This commit changes the ref setting strategy to work around the issue of
stale closures: we define a setRef method on ComponentNode that is
always called, this method ignores calls with `null`, meaning that the
refs object on the ComponentNode never reverts to a null value for any
key. Instead, the useRef hook will check whether the element that the
ref points to is still mounted, and return null if not.
Before this commit, properties were just handled as a special case of
attributes. But it does not make that much sense, since they are
different. For example, the `readOnly` property does not have the same
name as the `readonly` attribute. The confusion probably comes from the
fact that QWeb does not distinguish between property and attributes, so
Owl has to infer which one is which.
With this commit, we introduce a `block-property` directive in blockdom,
and change the compiler to use it in emitted code. It has the additional
benefits of slightly shrinking the runtime code, since the `isProp`
function can now be located in the compiler.
Have a t-ref on a DOM node with a t-key.
Change the t-key.
Before this commit, the old block removed its element from the component's refs *after*
the new block had been mounted, meaning that in effect, the resulting
ref at the end of the whole patch was null.
After this commit, we only remove an element from the component's ref if that very same
element was indeed the ref. (otherwise it means someone else has changed the ref.)
In dev mode, owl inserts an additional props validation step. Before
this commit, the validation would iterate on all key/value pairs of each
props. If the props is reactive, this has the unfortunate side effect of
subscribing the component to each of the keys, even though it should not
be.
This commit avoids the issue by only validating the raw object.
Previously, the getSubscriptions debugging utility returned all observed
keys for a given target, instead of only the keys observed by the
callback it received as argument. This commit fixes that issues.
Previously, when having a long lived reactive object and writing a lot
of keys to it, clearing the reactive subscriptions on that object would
slow down as time went on. This is because when clearing a target's
subsctiptions for a callback, we look at all the keys that are observed, and for all
the observed keys, we remove the callback from the set of callbacks
observing that key. The problem arises from the fact that after doing
that, even if the set of callbacks observing that key is now empty, we
don't remove the key from the observed keys, meaning that any further
clearing of subscriptions will have to iterate over that key to attempt
to clear the callbacks even if there are none.
This commit fixes this problem by simply removing the key from the
observedKeys if there are no longer any callbacks observing it.
This commit also improves performance for bare reactives (reactives
created with no callback). The initial implementation simply creates a
default empty callback when creating a reactive, and treats it like any
other, meaning it can observe keys and be notified of changes even
though we know in advance that it does nothing. This can compound with
the previous issue when you're doing a lot of manipulations on a bare
reactive internally for the sole purpose of notifying outside observers,
as this creates a lot of useless work in the reactivity system.
This commit exposes owl apps in a global variable so that the owl
devtools can hook themselves on these apps. While the devtools are not
yet ready to be merged, exposing the apps will allow us to test the
devtools in production scenarios while polishing the development of
them.
Previously the type of the target for useExternalListener was
HTMLElement or Window, this makes document an invalid target. Here there
is no reason to use the EventTarget interface instead, as
useExternalListener only uses methods from that interface and should
work with any event target.
Closesodoo/owl#1323
Géry Debongnie