add support for retrieve database API ✨

Author: KoditkarVedant

Src/Notion.Client/DatabaseClient.cs

@@ -1,10 +1,12 @@
+using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 
 namespace Notion.Client
 {
     public interface IDatabaseClient
     {
+        Task<Database> RetrieveAsync(string databaseId);
         Task<PaginatedList<Database>> ListAsync(DatabasesListParameters databasesListParameters = null);
     }
 
@@ -17,6 +19,19 @@ public DatabaseClient(IRestClient client)
             _client = client;
         }
 
+        public async Task<Database> RetrieveAsync(string databaseId)
+        {
+            try
+            {
+                return await _client.GetAsync<Database>($"databases/{databaseId}");
+            }
+            catch (Exception e)
+            {
+                // Todo: Throw Custom Exception
+                return null;
+            }
+        }
+
         public async Task<PaginatedList<Database>> ListAsync(DatabasesListParameters databasesListParameters = null)
         {
             try
@@ -29,7 +44,7 @@ public async Task<PaginatedList<Database>> ListAsync(DatabasesListParameters dat
 
                 return await _client.GetAsync<PaginatedList<Database>>("databases", queryParams);
             }
-            catch (System.Exception e)
+            catch (Exception e)
             {
                 // Todo: Throw Custom Exception
                 return null;

Test/Notion.UnitTests/DatabasesClientTests.cs

@@ -24,5 +24,13 @@ public async Task ListDatabasesAsync()
             var databasesList = await _client.ListAsync();
             Assert.NotNull(databasesList);
         }
+
+        [Fact(Skip =  "Internal Testing Purpose")]
+        public async Task RetrieveDatabaseAsync()
+        {
+            var databaseId = "";
+            var database = await _client.RetrieveAsync(databaseId);
+            Assert.NotNull(database);
+        }
     }
 }