i/7794: Introduce Insert Image via URL feature.

[panr]

Suggested merge commit message (convention)

Feature (image): Introduced insert image via URL feature. Closes #7794.

Other (image): Update ImageUploadUI plugin. From now the plugin appears as a dropdown with the split button. Primary action shows the native dialog for picking the images from the disk, and the arrow button opens the dropdown with the form for inserting an image via URL and configured integrations.

BREAKING CHANGE (image): Keep the ImageUploadCommand enabled when an image in the editor's content is selected. This allows us to replace the source URL of the image without the need to remove it.

[pomek]

As in the review, the most important case here is the API for the ImageUploadPanelView class.

[pomek]

TL;DR: integrations should be the second parameter. It should be an array that keeps View instances.

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And short "ADR" how I figured it out.

I would change the API a little bit:

Suggested change

	constructor( locale, options = { integrations: { insertImageViaUrl: 'insertImageViaUrl' } } ) {
	constructor( locale, integrations ) {

And integrations will be an array now. Items of the array could be:

[
    // Passing a `View` instance that renders the component.
    { name: 'name-for-integration-01', view: new CustomIntegrationView( /* ... */ ),

    // Passing a name of the View that is provided by the class by default.
    { name: 'integration-02', view: 'insertImageViaUrl'},

    // It won't happen directly since `prepareIntegrations()` function will filter out the invalid value. However, the class itself does not check what is being added.
    // We could assume that view will be always an instance of the `View` class.
    { name: 'integration-03', view: 'non-existing-item'},
]

The order of items in the array could determine the order in the Image Upload Panel view. Hence, the name key could be omitted and we could pass only View instances or the default string.

And at this point, I don't see any sense to support the string value here. From the ImageUploadPanelView class point of view, integrations should represent a collection (the array) of View elements.

Preparing proper values/view instances should be done a layer earlier.

[pomek]

Since the proposed (the comment above) changes will cause changes in the class itself, I am skipping reviewing this file and its tests.

[panr]

I think we should ask others. But ATM it looks like a followup.

[pomek]

It's sad that you can type whatever in the input and it won't be checked. I am unsure of what could we do here. Check whether passed a relative path or an absolute to the resource and validate the later one? I am thinking about the AutoLink regexp.

[pomek]

However…

So, we can't do here too much.

[pomek]

Suggested change

	labeledInputView.infoText = t( 'Paste the image source URL' );
	labeledInputView.infoText = t( 'Paste the image source URL.' );

Don't forget about updating contexts.json.

[pomek]

Same in L156. Missing the dot at the end of the sentence.

[panr]

Same in L156. Missing the dot at the end of the sentence.

But it's a form label. It shouldn't end with the dot 🤔

[panr]

@pomek changes applied, I hope it will be ✅ 👀

[pomek]

LGTM.

[Reinmar]

I've got doubts regarding how this feature should be proposed – as a separate plugin, an opt-in feature of the current UploadImage plugin or an opt-out feature of it.

I'll write a separate RFC for that.

[Reinmar]

We made a decision regarding how to propose this feature: #7794 (comment).

@panr, could you adjust the code? It may require a bit more changes as this will be a button or a split button depending on the config option.

[panr]

@Reinmar did the changes, now I'm on the docs update.