Implement a test mode
>>> [!note] Migrated issue
<!-- Drupal.org comment -->
<!-- Migrated from issue #3573059. -->
Reported by: [jurgenhaas](https://www.drupal.org/user/168924)
Related to !24
>>>
<h3 id="summary-problem-motivation">Problem/Motivation</h3>
<p>When building models, there's often no replay data available yet. Or there is replay data from before changes have been made to the model. Therefore, we need a test mode which is attached to an event, gives the user instructions on what to do, and then waiting for the test data being available, loaded and made available for replay/debugging.</p>
<h4 id="summary-steps-reproduce">Steps to reproduce</h4>
<h3 id="summary-proposed-resolution">Proposed resolution</h3>
<p>This feature makes the replay panel always visible (auto-collapsed when no data), adds a "Test" button to trigger a live test execution of a selected event, polls for results, and displays the replay data when available.</p>
<h4>Architecture Overview</h4>
<p>The core new piece is a <strong><code>useTestRunner</code></strong> hook that manages the test lifecycle (initiation, polling, cancellation, result handling). The ReplayPanel gets new props for test state, and Flow.tsx orchestrates everything.</p>
<hr>
<h4>1. Make Replay Panel Always Available (Auto-Collapse When No Data)</h4>
<p><strong>File: <code>Flow.tsx</code> (~line 549)</strong></p>
<ul>
<li>Remove the conditional <code>{(hasReplayData || replayData.length > 0) && (</code> wrapper around the ReplayPanel</li>
<li>The ReplayPanel will always render</li>
<li>Add logic: when there is no replay data AND no test is running, auto-collapse the panel on initial render
<ul>
<li>Add a <code>useEffect</code> that calls <code>toggleReplayPanelCollapse()</code> to collapse when <code>replayData.length === 0</code> and <code>!isTestRunning</code> and panel is not already collapsed</li>
<li>Only auto-collapse on data transitions (going from data → no data), not on every render</li>
</ul>
</li>
</ul>
<p><strong>File: <code>ReplayPanel.tsx</code> (~line 184-186)</strong></p>
<ul>
<li>Remove the <code>if (!isVisible) { return null; }</code> early return (or always pass <code>isVisible={true}</code>)</li>
<li>Keep the empty state rendering (lines 188-203) but add the Test button to its header</li>
</ul>
<h4>2. Add <code>test_url</code> to Settings Type</h4>
<p><strong>File: <code>types/settings.ts</code> (~line 79)</strong></p>
<ul>
<li>Add <code>test_url?: string;</code> to <code>ModelerApiSettings</code></li>
</ul>
<h4>3. Create <code>useTestRunner</code> Hook</h4>
<p><strong>New file: <code>hooks/useTestRunner.ts</code></strong></p>
<p>This hook manages the full test lifecycle:</p>
<pre><pre>interface UseTestRunnerProps {<br> settings?: Settings;<br> hasUnsavedChanges: boolean;<br> showConfirmationDialog: (...) => void;<br> saveButtonRef: React.RefObject&lt;HTMLButtonElement&gt;;<br> onReplayDataReceived: (data: ReplayStep[]) => void;<br>}<br><br>interface UseTestRunnerReturn {<br> isTestRunning: boolean; // Whether a test is in progress (polling)<br> isTestInitiating: boolean; // Whether the initial request is in flight<br> testError: string | null;<br> startTest: (componentId: string) => void; // Called when Test button clicked<br> cancelTest: () => void;<br>}</pre></pre><p><strong>Logic flow:</strong></p>
<ol>
<li><code>startTest(componentId)</code>:
<ul>
<li>If <code>hasUnsavedChanges</code>, show confirmation dialog with "Save and test" / "Cancel"
<ul>
<li>"Save and test": programmatically click the save button, set a <code>pendingTestAfterSaveRef</code> flag</li>
<li>The <code>handleSaveComplete</code> callback in Flow.tsx will check this flag and call <code>proceedWithTest()</code></li>
</ul>
</li>
<li>If no unsaved changes, call <code>proceedWithTest()</code> directly</li>
</ul>
</li>
<li><code>proceedWithTest()</code>:
<ul>
<li>POST to <code>test_url</code> with <code>{ modelId, componentId }</code> (same CSRF pattern as <code>useReplayLoader</code>)</li>
<li>Parse response for <code>jobId</code></li>
<li>On error: set <code>testError</code>, show Drupal message</li>
<li>On success: store <code>jobId</code>, start polling</li>
</ul>
</li>
<li>Polling:
<ul>
<li><code>setInterval</code> every 1.5 seconds</li>
<li>POST to <code>test_url</code> with <code>{ jobId }</code></li>
<li>Response: <code>{ status: "waiting" }</code> → continue polling</li>
<li>Response: replay data array → call <code>onReplayDataReceived(data)</code>, stop polling</li>
<li>Error → set <code>testError</code>, stop polling</li>
</ul>
</li>
<li><code>cancelTest()</code>:
<ul>
<li>Abort any in-flight fetch via <code>AbortController</code></li>
<li>Clear the polling interval</li>
<li>Reset all test state</li>
</ul>
</li>
</ol>
<p><strong>Cleanup:</strong> <code>useEffect</code> cleanup to abort and clear interval on unmount.</p>
<h4>4. Detect Selected Event (with Auto-Detection)</h4>
<p><strong>In Flow.tsx:</strong></p>
<ul>
<li>Derive <code>selectedEventNodeId</code>:<br>
<pre><pre>const selectedEventNodeId = useMemo(() => {<br> // If a start node is selected, use it<br> if (selectedNode?.type === 'start') return selectedNode.id;<br> // If only one event exists in the model, auto-detect it<br> const eventNodes = nodes.filter(n => n.type === 'start');<br> if (eventNodes.length === 1) return eventNodes[0].id;<br> return null;<br>}, [selectedNode, nodes]);</pre></pre></li>
<li>Pass <code>selectedEventNodeId</code> to ReplayPanel as a new prop</li>
</ul>
<h4>5. Wire Test into Flow.tsx</h4>
<p><strong>File: <code>Flow.tsx</code></strong></p>
<ul>
<li>Instantiate <code>useTestRunner</code> with the required props</li>
<li>Add a <code>handleSaveCompleteForTest</code> mechanism: modify <code>handleSaveComplete</code> (or the <code>onSaveComplete</code> callback) to check a <code>pendingTestRef</code> and call <code>proceedWithTest</code> after save succeeds</li>
<li>Pass test state (<code>isTestRunning</code>, <code>isTestInitiating</code>, <code>testError</code>, <code>startTest</code>, <code>cancelTest</code>) as props to ReplayPanel</li>
<li>When <code>onReplayDataReceived</code> fires, convert the data into <code>ReplayEntry[]</code> format and call <code>handleReplayEntriesLoaded</code></li>
</ul>
<h4>6. Update ReplayPanel Props and UI</h4>
<p><strong>File: <code>ReplayPanel.tsx</code></strong></p>
<p>New props:</p>
<pre><pre>interface ReplayPanelProps {<br> // ... existing props ...<br> selectedEventNodeId?: string | null;<br> hasTestUrl?: boolean;<br> isTestRunning?: boolean;<br> isTestInitiating?: boolean;<br> testError?: string | null;<br> onStartTest?: (componentId: string) => void;<br> onCancelTest?: () => void;<br>}</pre></pre><p><strong>Header changes (lines 234-254):</strong></p>
<ul>
<li>Add a "Test" button next to the info button:<br>
<pre><pre>{selectedEventNodeId && hasTestUrl && !isTestRunning && (<br> &lt;button<br> className="header-test-btn"<br> onClick={() => onStartTest?.(selectedEventNodeId)}<br> title={t('Test this event')}<br> aria-label={t('Test this event')}<br> disabled={isTestInitiating}<br> &gt;<br> &lt;FiPlay /&gt; {t('Test')}<br> &lt;/button&gt;<br>)}</pre></pre></li>
<li>The button uses the existing <code>header-*-btn</code> pattern but slightly wider to accommodate text</li>
</ul>
<p><strong>Test waiting state (new section, rendered instead of the step list when <code>isTestRunning</code>):</strong></p>
<pre><pre>{isTestRunning && (<br> &lt;div className="replay-test-waiting"&gt;<br> &lt;FiRefreshCw className="spinning" /&gt;<br> &lt;h4&gt;{t('Waiting for test execution...')}&lt;/h4&gt;<br> &lt;p&gt;{t('Trigger the selected event on your Drupal site to execute the workflow and capture the results.')}&lt;/p&gt;<br> &lt;button className="btn btn-secondary" onClick={onCancelTest}&gt;<br> {t('Cancel')}<br> &lt;/button&gt;<br> &lt;/div&gt;<br>)}</pre></pre><p><strong>Empty state update (lines 188-203):</strong></p>
<ul>
<li>Add the Test button to the empty state header as well, so the user can start a test when no replay data exists</li>
</ul>
<h4>7. CSS Styling</h4>
<p><strong>File: <code>styles/modeler.css</code></strong></p>
<p>Add styles for:</p>
<ul>
<li><code>.header-test-btn</code> — similar to other header buttons but with text, so slightly wider. Uses primary color to stand out:<br>
<pre><pre>.header-test-btn {<br> padding: 4px 10px;<br> background: var(--modeler-color-primary);<br> color: white;<br> border: 1px solid var(--modeler-color-primary);<br> border-radius: var(--modeler-radius-md);<br> cursor: pointer;<br> display: flex;<br> align-items: center;<br> gap: 4px;<br> font-size: var(--modeler-font-size-md);<br> transition: var(--modeler-transition-default);<br> height: 28px;<br>}</pre></pre></li>
<li><code>.replay-test-waiting</code> — centered content area with spinning icon, explanatory text, and cancel button:<br>
<pre><pre>.replay-test-waiting {<br> display: flex;<br> flex-direction: column;<br> align-items: center;<br> justify-content: center;<br> padding: 40px 20px;<br> text-align: center;<br> gap: 12px;<br> color: var(--modeler-color-text-secondary);<br>}</pre></pre></li>
</ul>
<h4>8. Integration: Save-Then-Test Flow</h4>
<p>The trickiest part is coordinating save → test. The approach mirrors the existing "Save and Close" pattern in <code>useCloseHandler</code>:</p>
<ol>
<li>In <code>useTestRunner</code>, store a <code>pendingTestRef</code> with the <code>componentId</code></li>
<li>When "Save and test" is clicked in the confirmation dialog:
<ul>
<li>Set <code>pendingTestRef.current = componentId</code></li>
<li>Programmatically click <code>saveButtonRef.current</code></li>
</ul>
</li>
<li>Modify <code>Flow.tsx</code>'s <code>onSaveComplete</code> callback:
<ul>
<li>After <code>setHasUnsavedChanges(false)</code>, check if <code>useTestRunner</code> has a pending test</li>
<li>If yes, call <code>proceedWithTest()</code></li>
</ul>
</li>
<li>This keeps the save mechanism untouched (existing Drupal AJAX flow)</li>
</ol>
<h4>9. Files Changed Summary</h4>
<table>
<thead>
<tr>
<th>File</th>
<th>Change Type</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>types/settings.ts</code></td>
<td>Edit</td>
<td>Add <code>test_url</code> to <code>ModelerApiSettings</code></td>
</tr>
<tr>
<td><code>hooks/useTestRunner.ts</code></td>
<td><strong>New</strong></td>
<td>Test lifecycle hook (initiate, poll, cancel)</td>
</tr>
<tr>
<td><code>components/Flow.tsx</code></td>
<td>Edit</td>
<td>Always render ReplayPanel, wire <code>useTestRunner</code>, pass new props, auto-collapse logic</td>
</tr>
<tr>
<td><code>components/ReplayPanel.tsx</code></td>
<td>Edit</td>
<td>New props, Test button in header, test waiting state UI</td>
</tr>
<tr>
<td><code>styles/modeler.css</code></td>
<td>Edit</td>
<td>Styles for test button and waiting state</td>
</tr>
</tbody>
</table>
<h4>10. Edge Cases & Error Handling</h4>
<ul>
<li><strong>No <code>test_url</code> in settings</strong>: Test button is hidden (<code>hasTestUrl</code> prop)</li>
<li><strong>Network error during test initiation</strong>: Shows error via <code>testError</code> + Drupal message, same pattern as <code>useReplayLoader</code></li>
<li><strong>Polling error</strong>: Stops polling, shows error</li>
<li><strong>Component unmount during polling</strong>: <code>useEffect</code> cleanup aborts fetch and clears interval</li>
<li><strong>User navigates away during test</strong>: Cleanup handles this</li>
<li><strong>Multiple rapid Test clicks</strong>: <code>AbortController</code> cancels previous request (same pattern as <code>useReplayLoader</code>)</li>
<li><strong>Auto-collapse timing</strong>: Only auto-collapse when transitioning from data → no data, not when the panel first mounts with no data (so the user can explore the empty state)</li>
</ul>
<h3 id="summary-remaining-tasks">Remaining tasks</h3>
<h3 id="summary-ui-changes">User interface changes</h3>
<h3 id="summary-api-changes">API changes</h3>
<h3 id="summary-data-model-changes">Data model changes</h3>
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