flan/advanced-camera-card
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

perf(bundle): lazy-load the nunjucks template engine (#2535)

Browse Source 
Closes #2531.

## Summary

The full `nunjucks` templating engine (~226KB) plus `ha-nunjucks`
(~46KB) — roughly **272KB, ~13% of the eager entry chunk** — was
statically imported and downloaded by every card on initial load, even
though templates only apply when a config value contains a `{{ … }}` /
`{% … %}` delimiter. Most cards use no templates and never need the
engine.

This defers the engine behind a dynamic `import('ha-nunjucks/dist')` so
it ships in a separate, on-demand chunk instead of the eager
`card-*.js`.

## Approach

The render path (`TemplateRenderer.renderRecursively`) is **kept
synchronous** — it is called from many synchronous hot paths
(condition/trigger evaluators, picture-elements rendering, actions,
folder matchers), and making it async would be a large, high-risk
refactor of the evaluation core.

Instead:

- **New `src/card-controller/templates/engine.ts`** — a module-level
singleton lazy loader (`loadTemplateEngine()` / `getTemplateEngine()`)
shared across all `TemplateRenderer` instances, plus a
`containsTemplate()` delimiter helper.
- **Delimiter gating** — strings without a delimiter never touch the
engine (the overwhelming majority of renders).
- **Pre-warm at config time** — because every template string originates
in the config, a new mandatory `TEMPLATE_ENGINE` initialization aspect
loads the engine before first render whenever the config contains a
delimiter. This **guarantees no raw `{{ … }}` flash**: content/condition
rendering is blocked until the engine is present for template-using
cards. Cards without templates never load it.

## Result

- nunjucks + ha-nunjucks move out of the eager chunk into a separate
chunk fetched only when a card actually uses templates.
- No change to the synchronous public render API; condition/trigger
evaluation core untouched.

## Tests

- New `engine.ts` loader coverage (concurrent load, cached reuse,
not-loaded fallback).
- The 11 existing test files that render real (delimiter-bearing)
templates declare their dependency explicitly via
`beforeAll(loadTemplateEngine)` — no global/implicit setup hook.
- Full suite green (4764 tests), lint and ts-prune clean, per-file 100%
coverage maintained for the affected directories.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

https://claude.ai/code/session_016ykWemdkZrgywvC71pHc6c

---
_Generated by [Claude
Code](https://claude.ai/code/session_016ykWemdkZrgywvC71pHc6c)_
This commit is contained in:
Dermot Duffy
2026-06-30 17:45:13 -07:00
committed by dermotduffy
parent b33c034810
commit ea251ca988
59 changed files with 1420 additions and 541 deletions
Download Patch File Download Diff File Expand all files Collapse all files
tests/card-controller/actions/actions-manager.test.ts
+58 -37
View File
@@ -8,7 +8,6 @@ import {
it,
vi,
} from 'vitest';
import { mock } from 'vitest-mock-extended';
import {
ActionsManager,
@@ -16,14 +15,20 @@ import {
type InteractionName,
} from '../../../src/card-controller/actions/actions-manager';
import type { CardController } from '../../../src/card-controller/controller';
import { TemplateRenderer } from '../../../src/card-controller/templates';
import { TemplateManager } from '../../../src/card-controller/templates';
import type { AdvancedCameraCardView } from '../../../src/config/schema/common/const';
import {
createInternalCallbackAction,
createLogAction,
} from '../../../src/utils/action';
import { arrayify } from '../../../src/utils/basic';
import { createCardAPI, createConfig, createHASS, createView } from '../../test-utils';
import {
createCardAPI,
createConfig,
createHASS,
createMockTemplateRenderer,
createView,
} from '../../test-utils';
const createAPI = (): CardController => {
const api = createCardAPI();
@@ -337,10 +342,9 @@ describe('ActionsManager', () => {
it('should render templates', async () => {
const action = createLogAction('{{ acc.camera }}');
const templateRenderer = mock<TemplateRenderer>();
templateRenderer.renderRecursivelyAsType.mockReturnValue(action);
const api = createAPI();
vi.mocked(api.getTemplateManager).mockReturnValue(createMockTemplateRenderer());
const hass = createHASS();
vi.mocked(api.getHASSManager().getHASS).mockReturnValue(hass);
@@ -349,7 +353,7 @@ describe('ActionsManager', () => {
};
vi.mocked(api.getConditionStateManager().getState).mockReturnValue(conditionState);
const manager = new ActionsManager(api, templateRenderer);
const manager = new ActionsManager(api);
const config = { entity: 'light.office' };
const triggerData = {
platform: 'acc',
@@ -361,10 +365,14 @@ describe('ActionsManager', () => {
await manager.executeActions({ actions: action, config, triggerData });
expect(templateRenderer.renderRecursivelyAsType).toBeCalledWith(hass, action, {
conditionState,
triggerData,
});
expect(vi.mocked(api.getTemplateManager().renderRecursivelyAsType)).toBeCalledWith(
hass,
action,
{
conditionState,
triggerData,
},
);
});
it('should filter actions through the lock manager before rendering them', async () => {
@@ -377,20 +385,18 @@ describe('ActionsManager', () => {
allowedRan();
});
const templateRenderer = mock<TemplateRenderer>();
templateRenderer.renderRecursivelyAsType.mockReturnValue(allowedAction);
const api = createAPI();
vi.mocked(api.getTemplateManager).mockReturnValue(createMockTemplateRenderer());
vi.mocked(api.getHASSManager().getHASS).mockReturnValue(createHASS());
vi.mocked(api.getLockManager().getAllowedActions).mockReturnValue([allowedAction]);
const manager = new ActionsManager(api, templateRenderer);
const manager = new ActionsManager(api);
await manager.executeActions({ actions: rawAction });
// The lock manager sees the raw (unrendered) action; only the action it
// returns is rendered and run.
expect(api.getLockManager().getAllowedActions).toBeCalledWith(rawAction);
expect(api.getLockManager().getAllowedActions).toBeCalledWith([rawAction]);
expect(allowedRan).toBeCalled();
expect(rawRan).not.toBeCalled();
});
@@ -398,17 +404,16 @@ describe('ActionsManager', () => {
it('should render each action against the state at its turn', async () => {
let camera = 'first';
const templateRenderer = mock<TemplateRenderer>();
// Identity render -- assert on the render *inputs*, not a swapped output.
templateRenderer.renderRecursivelyAsType.mockImplementation((_hass, data) => data);
const api = createAPI();
// The mock renderer passes values through, so assert on the render
// *inputs*, not a swapped output.
vi.mocked(api.getTemplateManager).mockReturnValue(createMockTemplateRenderer());
vi.mocked(api.getHASSManager().getHASS).mockReturnValue(createHASS());
vi.mocked(api.getConditionStateManager().getState).mockImplementation(() => ({
camera,
}));
const manager = new ActionsManager(api, templateRenderer);
const manager = new ActionsManager(api);
await manager.executeActions({
actions: [
@@ -423,13 +428,17 @@ describe('ActionsManager', () => {
// Each action renders with the state as it is at its turn: the second
// sees the camera the first action set.
expect(templateRenderer.renderRecursivelyAsType).toHaveBeenNthCalledWith(
expect(
vi.mocked(api.getTemplateManager().renderRecursivelyAsType),
).toHaveBeenNthCalledWith(
1,
expect.anything(),
expect.anything(),
expect.objectContaining({ conditionState: { camera: 'first' } }),
);
expect(templateRenderer.renderRecursivelyAsType).toHaveBeenNthCalledWith(
expect(
vi.mocked(api.getTemplateManager().renderRecursivelyAsType),
).toHaveBeenNthCalledWith(
2,
expect.anything(),
expect.anything(),
@@ -440,16 +449,14 @@ describe('ActionsManager', () => {
it('should render against the hass available at each step', async () => {
const ran: string[] = [];
const templateRenderer = mock<TemplateRenderer>();
templateRenderer.renderRecursivelyAsType.mockImplementation((_hass, data) => data);
const api = createAPI();
vi.mocked(api.getTemplateManager).mockReturnValue(createMockTemplateRenderer());
// No HASS for the first action's render; HASS thereafter.
vi.mocked(api.getHASSManager().getHASS)
.mockReturnValueOnce(null)
.mockReturnValue(createHASS());
const manager = new ActionsManager(api, templateRenderer);
const manager = new ActionsManager(api);
await manager.executeActions({
actions: [
@@ -465,23 +472,27 @@ describe('ActionsManager', () => {
// Both actions ran; only the second was rendered -- the first saw no
// HASS, so HASS is read per action rather than captured once.
expect(ran).toEqual(['one', 'two']);
expect(templateRenderer.renderRecursivelyAsType).toBeCalledTimes(1);
expect(
vi.mocked(api.getTemplateManager().renderRecursivelyAsType),
).toBeCalledTimes(1);
});
it('should abort the remaining actions when one fails to render', async () => {
const ran: string[] = [];
const templateRenderer = mock<TemplateRenderer>();
templateRenderer.renderRecursivelyAsType
const api = createAPI();
const renderer = createMockTemplateRenderer();
vi.mocked(api.getTemplateManager).mockReturnValue(renderer);
// The second action's render throws, to exercise a mid-sequence failure.
vi.mocked(renderer.renderRecursivelyAsType)
.mockImplementationOnce((_hass, data) => data)
.mockImplementationOnce(() => {
throw new Error('bad template');
});
const api = createAPI();
vi.mocked(api.getHASSManager().getHASS).mockReturnValue(createHASS());
const manager = new ActionsManager(api, templateRenderer);
const manager = new ActionsManager(api);
const warnSpy = vi.spyOn(global.console, 'warn').mockReturnValue(undefined);
await manager.executeActions({
@@ -511,7 +522,11 @@ describe('ActionsManager', () => {
fullscreen: true,
});
const manager = new ActionsManager(api, new TemplateRenderer());
// The if-action renders its own (non-branch) fields, so give it an
// identity renderer that passes the config through unchanged.
vi.mocked(api.getTemplateManager).mockReturnValue(createMockTemplateRenderer());
const manager = new ActionsManager(api);
const consoleSpy = vi.spyOn(global.console, 'info').mockReturnValue(undefined);
const thenAction = createLogAction('{{ trigger.entity_id }}');
@@ -527,7 +542,7 @@ describe('ActionsManager', () => {
// The branch is left raw (template intact) and forwarded with the trigger
// data, so the nested executor renders it per-step when it runs -- not
// frozen against the state at the `if` step.
expect(api.getActionsManager().executeActions).toBeCalledWith({
expect(api.getActionsManager().executeNestedActions).toBeCalledWith({
actions: [thenAction],
config: undefined,
triggerData: { platform: 'state', entity_id: 'binary_sensor.door' },
@@ -541,14 +556,20 @@ describe('ActionsManager', () => {
it('should render if-action branch actions per-step', async () => {
let camera = 'before';
// This case renders a real branch template, so load the lazily-imported
// engine for the synchronous renderer.
const templateManager = new TemplateManager();
await templateManager.loadRenderer();
const api = createAPI();
vi.mocked(api.getHASSManager().getHASS).mockReturnValue(createHASS());
vi.mocked(api.getConditionStateManager().getState).mockImplementation(() => ({
camera,
fullscreen: true,
}));
vi.mocked(api.getTemplateManager).mockReturnValue(templateManager);
const manager = new ActionsManager(api, new TemplateRenderer());
const manager = new ActionsManager(api);
// The if-action's nested executor is the same (real) manager.
vi.mocked(api.getActionsManager).mockReturnValue(manager);
@@ -578,7 +599,7 @@ describe('ActionsManager', () => {
const api = createAPI();
vi.mocked(api.getHASSManager().getHASS).mockReturnValue(createHASS());
const manager = new ActionsManager(api, new TemplateRenderer());
const manager = new ActionsManager(api);
const warnSpy = vi.spyOn(global.console, 'warn').mockReturnValue(undefined);
await manager.executeActions({