feat(api): add news to /api/meta response

Catalogger.Backend/Api/ApiCache.cs

@@ -14,11 +14,43 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 using Catalogger.Backend.Database.Redis;
+using Remora.Discord.API;
+using Remora.Discord.API.Abstractions.Objects;
+using Remora.Discord.API.Abstractions.Rest;
 
 namespace Catalogger.Backend.Api;
 
-public class ApiCache(RedisService redisService)
+public class ApiCache(RedisService redisService, IDiscordRestChannelAPI channelApi, Config config)
 {
+    private List<IMessage>? _news;
+    private readonly SemaphoreSlim _newsSemaphore = new(1);
+
+    public async Task<List<IMessage>> GetNewsAsync()
+    {
+        await _newsSemaphore.WaitAsync();
+        try
+        {
+            if (_news != null)
+                return _news;
+
+            if (config.Web.NewsChannel == null)
+                return [];
+
+            var res = await channelApi.GetChannelMessagesAsync(
+                DiscordSnowflake.New(config.Web.NewsChannel.Value),
+                limit: 5
+            );
+            if (res.IsSuccess)
+                return _news = res.Entity.ToList();
+
+            return [];
+        }
+        finally
+        {
+            _newsSemaphore.Release();
+        }
+    }
+
     private static string UserKey(string id) => $"api-user:{id}";
 
     private static string GuildsKey(string userId) => $"api-user-guilds:{userId}";

Catalogger.Backend/Api/GuildsController.cs

@@ -31,7 +31,6 @@ namespace Catalogger.Backend.Api;
 
 [Route("/api/guilds/{id}")]
 public partial class GuildsController(
-    Config config,
     ILogger logger,
     DatabaseContext db,
     ChannelCache channelCache,

Catalogger.Backend/Api/MetaController.cs

@@ -15,7 +15,10 @@
 
 using Catalogger.Backend.Api.Middleware;
 using Catalogger.Backend.Cache.InMemoryCache;
+using Catalogger.Backend.Extensions;
+using Catalogger.Backend.Services;
 using Microsoft.AspNetCore.Mvc;
+using Remora.Discord.API.Abstractions.Objects;
 
 namespace Catalogger.Backend.Api;
 
@@ -23,20 +26,24 @@ namespace Catalogger.Backend.Api;
 public class MetaController(
     Config config,
     GuildCache guildCache,
+    NewsService newsService,
     DiscordRequestService discordRequestService
 ) : ApiControllerBase
 {
     [HttpGet("meta")]
-    public IActionResult GetMeta()
+    public async Task<IActionResult> GetMetaAsync()
     {
         var inviteUrl =
             $"https://discord.com/oauth2/authorize?client_id={config.Discord.ApplicationId}"
             + "&permissions=537250993&scope=bot+applications.commands";
 
+        var news = await newsService.GetNewsAsync();
+
         return Ok(
             new MetaResponse(
                 Guilds: (int)CataloggerMetrics.GuildsCached.Value,
-                InviteUrl: inviteUrl
+                InviteUrl: inviteUrl,
+                News: news
             )
         );
     }
@@ -60,7 +67,11 @@ public class MetaController(
         );
     }
 
-    private record MetaResponse(int Guilds, string InviteUrl);
+    private record MetaResponse(
+        int Guilds,
+        string InviteUrl,
+        IEnumerable<NewsService.NewsMessage> News
+    );
 
     private record CurrentUserResponse(ApiUser User, IEnumerable<ApiGuild> Guilds);
 }