MishkaCmsCore.Runtime.LiveViewHelpers for the surfaces that render a template to a STRING.
Why a second module rather than a flag
Calling a stateful component produces a %Phoenix.LiveView.Component{}, which only a LiveView's
diff turns into HTML — asked for iodata it raises:
** (ArgumentError) cannot convert component … to HTML.
A component must always be returned directly as part of a LiveView template.Four surfaces render a runtime template to a string and then hand the string somewhere that is not
a LiveView: the admin's Preview tab and its version previews
(MishkaCmsCore.Runtime.RuntimePreview), the palette's card thumbnails
(MishkaCmsCore.Runtime.PageBuilder.CardPreview), the examples encoder, and the public
draft-preview URL. Before this, a page holding a live component gave every one of them that
message instead of a picture.
Which one a template gets is decided by the CALLER's import list, not by the template.
LiveViewCompiler.render_template/2 builds its own eval environment, and that environment is our
code rather than a generated module — so swapping the import there fixes all four at once, and
nothing a kit or an author writes can reach past it. A compiled page module imports the live
LiveViewHelpers and is unaffected: a published page IS a LiveView and must get the real thing.
What a reader sees instead
The component's own markup in its cold state — mount/1, then the compiler's update_many/1,
then render/1 as the ordinary arity-1 function it is. Real markup, real size, real styling, with
@myself nil so phx-target renders away. That is the same picture the builder's canvas draws,
and for the same reason: a preview is a picture of a page, and a picture does not respond to
clicks.
Everything else is the same module
This delegates the rest of the public surface rather than reimplementing it. The eval environment imports the whole module, so a function missing here is a function a template can no longer call — which is how a preview surface breaks silently.
Summary
Functions
The captcha a form asks, as the same markup — a preview draws its box, which nothing fills.
See MishkaCmsCore.Captcha.Widget.captcha/1.
A runtime component, rendered as markup rather than as something LiveView will run.
The same, from a name/site pair with extra assigns merged — LiveViewHelpers.component/3's shape.
Builds the runtime module for name/site if it is not loaded, and says whether it is.
LiveViewHelpers.rich_content/1 as markup: a stateful component a marker names is drawn cold, and
a marker the published page draws nothing for says why in its place.
A public address on the site being previewed — LiveViewHelpers.site_path/2.
The same renderer under its own name, for a template that calls static_component/1 directly.
A word in the language the preview is answering in — LiveViewHelpers.t/2. Missing here, a page
that calls t("…") previewed as "Preview unavailable" while the published page rendered it.
Functions
The captcha a form asks, as the same markup — a preview draws its box, which nothing fills.
See MishkaCmsCore.Captcha.Widget.captcha/1.
A runtime component, rendered as markup rather than as something LiveView will run.
The signature component/1 on purpose: the template says <.component component_name="…"/> and
does not know, or need to know, which environment it was evaluated in.
The same, from a name/site pair with extra assigns merged — LiveViewHelpers.component/3's shape.
Builds the runtime module for name/site if it is not loaded, and says whether it is.
LiveViewHelpers.rich_content/1 as markup: a stateful component a marker names is drawn cold, and
a marker the published page draws nothing for says why in its place.
A public address on the site being previewed — LiveViewHelpers.site_path/2.
The same renderer under its own name, for a template that calls static_component/1 directly.
component/1 above is the name a runtime template uses; this is here because the eval environment
imports the whole module and a function missing from it is one a template can no longer call.
A word in the language the preview is answering in — LiveViewHelpers.t/2. Missing here, a page
that calls t("…") previewed as "Preview unavailable" while the published page rendered it.