Add Slack-compatible incident RSS feed

database/seeders/DatabaseSeeder.php

@@ -232,6 +232,22 @@ public function run(): void
 
         $incident->updates()->save($update);
 
+        $incident = Incident::create([
+            'name' => 'Documentation Search Unavailable',
+            'message' => 'We are investigating an issue preventing searches in the documentation from returning results.',
+            'status' => IncidentStatusEnum::investigating,
+            'visible' => ResourceVisibilityEnum::guest,
+            'guid' => Str::uuid(),
+            'user_id' => $user->id,
+            'created_at' => $timestamp = now()->subMinutes(2),
+            'updated_at' => $timestamp,
+            'occurred_at' => $timestamp,
+        ]);
+
+        $incident->components()->attach($documentation, [
+            'component_status' => ComponentStatusEnum::partial_outage,
+        ]);
+
         IncidentTemplate::create([
             'name' => 'Third-Party Service Outage',
             'slug' => 'third-party-service-outage',

resources/views/components/incident.blade.php

@@ -67,7 +67,7 @@ class="text-zinc-400 transition hover:text-zinc-700 dark:text-zinc-500 dark:hove
                     </div>
                     <div class="flex flex-col divide-y divide-zinc-900/10 px-4 dark:divide-white/15 sm:px-6">
                         @foreach ($incident->updates as $update)
-                            <div data-component="incident-update" data-update-id="{{ $update->getKey() }}" class="relative py-5 sm:last:pb-6" x-data="{ timestamp: new Date(@js($update->created_at)) }">
+                            <div @if($headingLevel === 1) id="update-{{ $update->getKey() }}" @endif data-component="incident-update" data-update-id="{{ $update->getKey() }}" class="relative py-5 sm:last:pb-6" x-data="{ timestamp: new Date(@js($update->created_at)) }">
                                 <x-cachet::incident-update-status :status="$update->status" />
                                 @if ($headingLevel === 1)
                                     <h2 class="text-sm font-semibold tracking-tight text-zinc-900 dark:text-zinc-100 sm:text-base">{{ $update->status->getLabel() }}</h2>
@@ -80,7 +80,7 @@ class="text-zinc-400 transition hover:text-zinc-700 dark:text-zinc-500 dark:hove
                                 <div data-slot="message" class="prose-sm md:prose prose-zinc dark:prose-invert prose-a:text-accent-content prose-a:underline prose-p:leading-normal mt-2">{!! $update->formattedMessage() !!}</div>
                             </div>
                         @endforeach
-                        <div data-component="incident-update" data-update-id="reported" class="relative py-5 sm:last:pb-6" x-data="{ timestamp: new Date(@js($incident->timestamp)) }">
+                        <div @if($headingLevel === 1) id="reported" @endif data-component="incident-update" data-update-id="reported" class="relative py-5 sm:last:pb-6" x-data="{ timestamp: new Date(@js($incident->timestamp)) }">
                             @php($reportStatus = $incident->updates->isEmpty() ? $incident->status : null)
                             <x-cachet::incident-update-status :status="$reportStatus ?? IncidentStatusEnum::unknown" />
                             @if ($headingLevel === 1)

resources/views/slack-rss.blade.php

@@ -0,0 +1,39 @@
+<?=
+'<?xml version="1.0" encoding="utf-8"?>'.PHP_EOL
+?>
+<rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:content="http://purl.org/rss/1.0/modules/content/">
+    <channel>
+        <title>{{ $statusPageName }} incident updates</title>
+        <link>{{ route('cachet.status-page') }}</link>
+        <description>Latest incident reports and updates from {{ $statusPageName }}</description>
+        <lastBuildDate>{{ now()->toRssString() }}</lastBuildDate>
+        <docs>https://validator.w3.org/feed/docs/rss2.html</docs>
+        <generator>Cachet</generator>
+        @foreach($items as $item)
+        @php
+            $incident = $item['incident'];
+            $update = $item['update'];
+            $status = $update ? ($update->status?->getLabel() ?? 'Updated') : 'Reported';
+            $message = $update?->formattedMessage() ?? $incident->formattedMessage();
+            $url = route('cachet.status-page.incident', $incident).'#'.($update ? 'update-'.$update->id : 'reported');
+            $title = str_replace(']]>', ']]]]><![CDATA[>', '['.$status.'] '.$incident->name);
+            $description = $message.'<br/><br/><strong>Status:</strong> '.e($status);
+
+            if ($incident->components->isNotEmpty()) {
+                $components = $incident->components->pluck('name')->map(fn (string $name): string => e($name))->join(', ');
+                $description .= '<br/><strong>Affected components:</strong> '.$components;
+            }
+
+            $description = str_replace(']]>', ']]]]><![CDATA[>', $description);
+        @endphp
+        <item>
+            <title><![CDATA[{!! $title !!}]]></title>
+            <link>{{ $url }}</link>
+            <guid>{{ $url }}</guid>
+            <pubDate>{{ $item['publishedAt']->toRssString() }}</pubDate>
+            <description><![CDATA[{!! $description !!}]]></description>
+            <content:encoded><![CDATA[{!! $description !!}]]></content:encoded>
+        </item>
+        @endforeach
+    </channel>
+</rss>

src/Http/Controllers/SlackRssController.php

@@ -0,0 +1,135 @@
+<?php
+
+namespace Cachet\Http\Controllers;
+
+use Cachet\Models\Incident;
+use Cachet\Models\Update;
+use Cachet\Settings\AppSettings;
+use Carbon\Carbon;
+use Illuminate\Database\Eloquent\Builder;
+use Illuminate\Http\Request;
+use Illuminate\Http\Response;
+use Illuminate\Support\Collection;
+use Illuminate\Support\Facades\Cache;
+
+class SlackRssController
+{
+    /**
+     * The maximum number of incident events included in the feed.
+     */
+    private const MAX_ITEMS = 100;
+
+    /**
+     * How long the rendered feed is cached for, in seconds.
+     */
+    private const CACHE_TTL = 60;
+
+    /**
+     * Returns the incident event feed consumed by Slack.
+     */
+    public function __invoke(Request $request, AppSettings $appSettings): Response
+    {
+        $feed = Cache::remember('cachet::slack-rss-feed', self::CACHE_TTL, function () use ($appSettings) {
+            return view('cachet::slack-rss', [
+                'statusPageName' => $appSettings->name,
+                'items' => $this->items($this->feedIncidents($appSettings)),
+            ])->render();
+        });
+
+        $lastModified = Cache::remember('cachet::slack-rss-feed-last-modified', self::CACHE_TTL, fn () => now());
+
+        $response = response($feed)
+            ->header('Content-Type', 'application/rss+xml')
+            ->setEtag(hash('sha256', $feed))
+            ->setLastModified($lastModified)
+            ->setPublic()
+            ->setMaxAge(self::CACHE_TTL);
+
+        $response->isNotModified($request);
+
+        return $response;
+    }
+
+    /**
+     * Get incidents that can contribute one of the newest feed events.
+     *
+     * @return Collection<int, Incident>
+     */
+    private function feedIncidents(AppSettings $appSettings): Collection
+    {
+        $incidents = $this->incidentQuery($appSettings);
+
+        $incidentIds = (clone $incidents)
+            ->orderByDesc('created_at')
+            ->limit(self::MAX_ITEMS)
+            ->pluck('id');
+
+        $updatedIncidentIds = Update::query()
+            ->where('updateable_type', (new Incident)->getMorphClass())
+            ->whereIn('updateable_id', (clone $incidents)->select('id'))
+            ->orderByDesc('created_at')
+            ->limit(self::MAX_ITEMS)
+            ->pluck('updateable_id');
+
+        return (clone $incidents)
+            ->whereKey($incidentIds->concat($updatedIncidentIds)->unique())
+            ->with([
+                'components',
+                'updates' => fn ($query) => $query->orderBy('created_at')->orderBy('id'),
+            ])
+            ->get();
+    }
+
+    /**
+     * Build the public incident query shared by both candidate sets.
+     *
+     * @return Builder<Incident>
+     */
+    private function incidentQuery(AppSettings $appSettings): Builder
+    {
+        return Incident::query()
+            ->viewableBy(false)
+            ->when($appSettings->recent_incidents_only, function (Builder $query) use ($appSettings) {
+                $query->where(function (Builder $query) use ($appSettings) {
+                    $cutoff = Carbon::now()->subDays($appSettings->recent_incidents_days)->format('Y-m-d');
+
+                    $query->whereDate('occurred_at', '>', $cutoff)
+                        ->orWhere(function (Builder $query) use ($cutoff) {
+                            $query->whereNull('occurred_at')->whereDate('created_at', '>', $cutoff);
+                        });
+                });
+            });
+    }
+
+    /**
+     * Convert incidents and their updates into one chronological event stream.
+     *
+     * @param  Collection<int, Incident>  $incidents
+     * @return list<array{incident: Incident, update: ?Update, publishedAt: Carbon}>
+     */
+    private function items(Collection $incidents): array
+    {
+        /** @var list<array{incident: Incident, update: ?Update, publishedAt: Carbon}> $items */
+        $items = [];
+
+        foreach ($incidents as $incident) {
+            $items[] = [
+                'incident' => $incident,
+                'update' => null,
+                'publishedAt' => $incident->timestamp,
+            ];
+
+            foreach ($incident->updates as $update) {
+                $items[] = [
+                    'incident' => $incident,
+                    'update' => $update,
+                    'publishedAt' => $update->created_at ?? $incident->timestamp,
+                ];
+            }
+        }
+
+        usort($items, fn (array $left, array $right): int => $right['publishedAt']->getTimestamp() <=> $left['publishedAt']->getTimestamp());
+
+        return array_slice($items, 0, self::MAX_ITEMS);
+    }
+}

src/Models/Incident.php

@@ -274,12 +274,14 @@ protected function latestStatus(): Attribute
     }
 
     /**
-     * Clear the cached RSS feed and its HTTP validators.
+     * Clear the cached RSS feeds and their HTTP validators.
      */
     private static function forgetRssFeed(): void
     {
         Cache::forget('cachet::rss-feed');
         Cache::forget('cachet::rss-feed-last-modified');
+        Cache::forget('cachet::slack-rss-feed');
+        Cache::forget('cachet::slack-rss-feed-last-modified');
     }
 
     /**

src/Models/Update.php

@@ -78,13 +78,15 @@ public function formattedMessage(): string
     }
 
     /**
-     * Clear the RSS feed when an incident update changes its content.
+     * Clear the RSS feeds when an incident update changes its content.
      */
     private function forgetRssFeed(): void
     {
         if ($this->updateable instanceof Incident) {
             Cache::forget('cachet::rss-feed');
             Cache::forget('cachet::rss-feed-last-modified');
+            Cache::forget('cachet::slack-rss-feed');
+            Cache::forget('cachet::slack-rss-feed-last-modified');
         }
     }
 

src/PendingRouteRegistration.php

@@ -6,6 +6,7 @@
 use Cachet\Http\Controllers\HealthController;
 use Cachet\Http\Controllers\RssController;
 use Cachet\Http\Controllers\Setup\SetupController;
+use Cachet\Http\Controllers\SlackRssController;
 use Cachet\Http\Controllers\StatusPage\ComponentBadgeController;
 use Cachet\Http\Controllers\StatusPage\StatusBadgeController;
 use Cachet\Http\Controllers\StatusPage\StatusPageController;
@@ -64,6 +65,10 @@ public function register(): void
                     ->middleware('throttle:60,1')
                     ->name('rss');
 
+                $router->get('/slack.rss', SlackRssController::class)
+                    ->middleware('throttle:60,1')
+                    ->name('slack-rss');
+
             });
 
         $this->registerEmailVerificationRoutes();