feat: read what members are listening to from Last.fm

.env.example

@@ -89,6 +89,8 @@ GITHUB_REDIRECT_URI="${APP_URL}/auth/github/callback"
 GITHUB_APP_ID=
 GITHUB_APP_PRIVATE_KEY=
 
+LASTFM_API_KEY=
+
 # New GitHub accounts must be at least this many days old, and have a verified primary email,
 # before they can sign up. Both apply to the first sign-in only.
 SIGNUP_MIN_ACCOUNT_AGE_DAYS=7

app/Actions/CreateExport.php

@@ -104,6 +104,7 @@ public function handle(User $user): array
                 'live_platform' => $user->live_platform?->value,
                 'live_url' => $user->live_url,
                 'live_ends_at' => $user->live_ends_at?->toIso8601String(),
+                'lastfm_username' => $user->lastfm_username,
                 'last_seen_at' => $user->last_seen_at?->toDateString(),
                 'commit_rules_accepted_at' => $user->commit_rules_accepted_at?->toIso8601String(),
                 'emails_unsubscribed_at' => $user->emails_unsubscribed_at?->toIso8601String(),

app/Actions/DeleteUserNowPlaying.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Actions;
+
+use App\Models\User;
+
+final readonly class DeleteUserNowPlaying
+{
+    public function handle(User $user): void
+    {
+        $user->update(['lastfm_username' => null]);
+    }
+}

app/Actions/UpdateUserNowPlaying.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Actions;
+
+use App\Models\User;
+
+final readonly class UpdateUserNowPlaying
+{
+    public function handle(User $user, string $lastFmUsername): void
+    {
+        $user->update(['lastfm_username' => $lastFmUsername]);
+    }
+}

app/Contracts/Services/LastFmProvider.php

@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Contracts\Services;
+
+use App\Dto\Track;
+use Illuminate\Http\Client\HttpClientException;
+
+interface LastFmProvider
+{
+    /**
+     * @throws HttpClientException
+     */
+    public function exists(string $username): bool;
+
+    /**
+     * @throws HttpClientException
+     */
+    public function nowPlaying(string $username): ?Track;
+}

app/Dto/Track.php

@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Dto;
+
+use Illuminate\Contracts\Support\Arrayable;
+
+/**
+ * @implements Arrayable<string, string|null>
+ */
+final readonly class Track implements Arrayable
+{
+    public function __construct(
+        public string $artist,
+        public string $title,
+        public ?string $album,
+        public ?string $url,
+    ) {
+        //
+    }
+
+    /**
+     * @return array{artist: string, title: string, album: string|null, url: string|null}
+     */
+    public function toArray(): array
+    {
+        return [
+            'artist' => $this->artist,
+            'title' => $this->title,
+            'album' => $this->album,
+            'url' => $this->url,
+        ];
+    }
+}

app/Enums/Feature.php

@@ -11,12 +11,13 @@ enum Feature: string
 {
     case Translations = 'translations';
     case OrganizationCommits = 'organization_commits';
+    case NowPlaying = 'now_playing';
 
     /**
      * Features are on until switched off, except one still being built, which stays off until switched on.
      */
     public function isEnabledByDefault(): bool
     {
-        return $this !== self::OrganizationCommits;
+        return ! in_array($this, [self::OrganizationCommits, self::NowPlaying], true);
     }
 }

app/Http/Controllers/UserNowPlayingController.php

@@ -0,0 +1,38 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Http\Controllers;
+
+use App\Actions\DeleteUserNowPlaying;
+use App\Actions\UpdateUserNowPlaying;
+use App\Http\Requests\UpdateUserNowPlayingRequest;
+use App\Models\User;
+use App\Queries\NowPlayingQuery;
+use Illuminate\Container\Attributes\CurrentUser;
+use Illuminate\Http\JsonResponse;
+use Illuminate\Http\RedirectResponse;
+
+final readonly class UserNowPlayingController
+{
+    public function show(#[CurrentUser] ?User $currentUser, User $user, NowPlayingQuery $nowPlaying): JsonResponse
+    {
+        return response()->json([
+            'track' => $currentUser?->blockerIdWith($user) === null ? $nowPlaying->get($user) : null,
+        ])->header('Cache-Control', 'no-store, private');
+    }
+
+    public function update(UpdateUserNowPlayingRequest $request, #[CurrentUser] User $user, UpdateUserNowPlaying $action): RedirectResponse
+    {
+        $action->handle($user, $request->lastFmUsername());
+
+        return back();
+    }
+
+    public function destroy(#[CurrentUser] User $user, DeleteUserNowPlaying $action): RedirectResponse
+    {
+        $action->handle($user);
+
+        return back();
+    }
+}

app/Http/Requests/UpdateUserNowPlayingRequest.php

@@ -0,0 +1,32 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Http\Requests;
+
+use App\Rules\LastFmUsername;
+use Illuminate\Contracts\Validation\ValidationRule;
+use Illuminate\Foundation\Http\FormRequest;
+
+final class UpdateUserNowPlayingRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    /**
+     * @return array<string, list<string|ValidationRule>>
+     */
+    public function rules(): array
+    {
+        return [
+            'lastfm_username' => ['bail', 'required', 'string', new LastFmUsername()],
+        ];
+    }
+
+    public function lastFmUsername(): string
+    {
+        return $this->string('lastfm_username')->value();
+    }
+}

app/Models/User.php

@@ -57,6 +57,7 @@
  * @property-read LivePlatform|null $live_platform
  * @property-read string|null $live_url
  * @property-read CarbonInterface|null $live_ends_at
+ * @property-read string|null $lastfm_username
  * @property-read Log $log
  * @property-read CarbonInterface|null $onboarded_at
  * @property-read CarbonInterface|null $github_follows_imported_at
@@ -115,6 +116,7 @@
     'live_platform',
     'live_url',
     'live_ends_at',
+    'lastfm_username',
     'last_seen_at',
     'banned_at',
     'commit_rules_accepted_at',
@@ -164,6 +166,7 @@ final class User extends Authenticatable
         'live_platform' => null,
         'live_url' => null,
         'live_ends_at' => null,
+        'lastfm_username' => null,
         'last_seen_at' => null,
         'banned_at' => null,
         'commit_rules_accepted_at' => null,
@@ -212,6 +215,7 @@ public function casts(): array
             'live_platform' => LivePlatform::class,
             'live_url' => 'string',
             'live_ends_at' => 'datetime',
+            'lastfm_username' => 'string',
             'last_seen_at' => 'date',
             'banned_at' => 'datetime',
             'commit_rules_accepted_at' => 'datetime',

app/Providers/AppServiceProvider.php

@@ -9,6 +9,7 @@
 use App\Contracts\Services\EmbeddingProvider;
 use App\Contracts\Services\GitHubProvider;
 use App\Contracts\Services\HeadlineProvider;
+use App\Contracts\Services\LastFmProvider;
 use App\Contracts\Services\LinkPreviewProvider;
 use App\Contracts\Services\ModerationProvider;
 use App\Contracts\Services\PushNotificationProvider;
@@ -30,6 +31,8 @@
 use App\Services\GitHubProviders\NullGitHubProvider;
 use App\Services\HeadlineProviders\NullHeadlineProvider;
 use App\Services\HeadlineProviders\OpenAIHeadlineProvider;
+use App\Services\LastFmProviders\HttpLastFmProvider;
+use App\Services\LastFmProviders\NullLastFmProvider;
 use App\Services\LinkPreviewProviders\HttpLinkPreviewProvider;
 use App\Services\LinkPreviewProviders\NullLinkPreviewProvider;
 use App\Services\ModerationProviders\NullModerationProvider;
@@ -68,6 +71,7 @@ final class AppServiceProvider extends ServiceProvider
         EmbeddingProvider::class => OpenAIEmbeddingProvider::class,
         GitHubProvider::class => HttpGitHubProvider::class,
         HeadlineProvider::class => OpenAIHeadlineProvider::class,
+        LastFmProvider::class => HttpLastFmProvider::class,
         LinkPreviewProvider::class => HttpLinkPreviewProvider::class,
         ModerationProvider::class => OpenAIModerationProvider::class,
         PushNotificationProvider::class => WebPushNotificationProvider::class,
@@ -88,6 +92,7 @@ final class AppServiceProvider extends ServiceProvider
         EmbeddingProvider::class => NullEmbeddingProvider::class,
         GitHubProvider::class => NullGitHubProvider::class,
         HeadlineProvider::class => NullHeadlineProvider::class,
+        LastFmProvider::class => NullLastFmProvider::class,
         LinkPreviewProvider::class => NullLinkPreviewProvider::class,
         ModerationProvider::class => NullModerationProvider::class,
         PushNotificationProvider::class => NullPushNotificationProvider::class,
@@ -240,6 +245,11 @@ private function bootRateLimitingDefaults(): void
             $request->user() instanceof User ? $this->userId($request) : 'ip:'.$request->ip(),
         ));
 
+        RateLimiter::for('now-playing', fn (Request $request): Limit => Limit::perMinute(60)->by(
+            $request->user() instanceof User ? $this->userId($request) : 'ip:'.$request->ip(),
+        ));
+        RateLimiter::for('lastfm-links', fn (Request $request): Limit => Limit::perMinute(10)->by($this->userId($request)));
+
         // Every issue lookup GitHub hasn't answered in the last five minutes costs a request out of the shared hourly budget,
         // which also keeps SSH keys in sync for the CLI, so it gets a budget of its own...
         RateLimiter::for('issue-suggestions', fn (Request $request): array => [

app/Queries/NowPlayingQuery.php

@@ -0,0 +1,53 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Queries;
+
+use App\Contracts\Services\LastFmProvider;
+use App\Enums\Feature;
+use App\Models\User;
+use App\Services\Features;
+use Illuminate\Http\Client\HttpClientException;
+use Illuminate\Support\Facades\Cache;
+
+final readonly class NowPlayingQuery
+{
+    private const int TTL = 30;
+
+    private const int FAILURE_TTL = 300;
+
+    public function __construct(private Features $features, private LastFmProvider $lastFm)
+    {
+        //
+    }
+
+    /**
+     * @return array{artist: string, title: string, album: string|null, url: string|null}|null
+     */
+    public function get(User $user): ?array
+    {
+        $username = $user->lastfm_username;
+
+        if ($username === null || ! $this->features->enabled(Feature::NowPlaying)) {
+            return null;
+        }
+
+        $key = 'lastfm-now-playing:'.mb_strtolower($username);
+
+        /** @var array{artist: string, title: string, album: string|null, url: string|null}|false|null $track */
+        $track = Cache::get($key);
+
+        if ($track === null) {
+            try {
+                $track = $this->lastFm->nowPlaying($username)?->toArray() ?? false;
+                Cache::put($key, $track, self::TTL);
+            } catch (HttpClientException) {
+                $track = false;
+                Cache::put($key, $track, self::FAILURE_TTL);
+            }
+        }
+
+        return $track === false ? null : $track;
+    }
+}

app/Rules/LastFmUsername.php

@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Rules;
+
+use App\Contracts\Services\LastFmProvider;
+use App\Enums\Feature;
+use App\Services\Features;
+use Closure;
+use Illuminate\Contracts\Validation\ValidationRule;
+use Illuminate\Http\Client\HttpClientException;
+
+final readonly class LastFmUsername implements ValidationRule
+{
+    public function validate(string $attribute, mixed $value, Closure $fail): void
+    {
+        if (! resolve(Features::class)->enabled(Feature::NowPlaying)) {
+            $fail("Sharing what you're listening to isn't available yet.");
+
+            return;
+        }
+
+        if (! is_string($value) || preg_match('/^[A-Za-z][A-Za-z0-9_-]{1,14}$/', $value) !== 1) {
+            $fail('Use your Last.fm username: 2 to 15 letters, numbers, dashes or underscores, starting with a letter.');
+
+            return;
+        }
+
+        try {
+            $exists = resolve(LastFmProvider::class)->exists($value);
+        } catch (HttpClientException) {
+            $fail("Last.fm isn't answering. Try again in a moment.");
+
+            return;
+        }
+
+        if (! $exists) {
+            $fail('There is no Last.fm account with that username.');
+        }
+    }
+}