Added SqliteMessageDraftStore.

Author: grokys

src/GitHub.App/Services/SqliteMessageDraftStore.cs

@@ -0,0 +1,128 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.Composition;
+using System.IO;
+using System.Linq;
+using System.Threading.Tasks;
+using GitHub.Extensions;
+using GitHub.Logging;
+using Newtonsoft.Json;
+using Rothko;
+using Serilog;
+using SQLite;
+
+namespace GitHub.Services
+{
+    /// <summary>
+    /// Stores drafts of messages in an SQL database.
+    /// </summary>
+    [Export(typeof(IMessageDraftStore))]
+    [PartCreationPolicy(CreationPolicy.Shared)]
+    public class SqliteMessageDraftStore : IMessageDraftStore
+    {
+        static readonly ILogger log = LogManager.ForContext<SqliteMessageDraftStore>();
+        readonly SQLiteAsyncConnection connection;
+
+        [ImportingConstructor]
+        public SqliteMessageDraftStore(IOperatingSystem os)
+        {
+            var path = Path.Combine(
+                os.Environment.GetApplicationDataPath(),
+                "drafts.db");
+            connection = new SQLiteAsyncConnection(path);
+        }
+
+        public async Task<T> GetDraft<T>(string key, string secondaryKey) where T : class
+        {
+            Guard.ArgumentNotEmptyString(key, nameof(key));
+            Guard.ArgumentNotNull(secondaryKey, nameof(secondaryKey));
+
+            try
+            {
+                var result = await connection.Table<Draft>().Where(
+                    x => x.Key == key && x.SecondaryKey == secondaryKey)
+                    .FirstOrDefaultAsync()
+                    .ConfigureAwait(false);
+
+                if (result != null)
+                {
+                    return JsonConvert.DeserializeObject<T>(result.Data);
+                }
+            }
+            catch (Exception ex)
+            {
+                log.Error(ex, "Failed to load message draft into {Type}", typeof(T));
+            }
+
+            return null;
+        }
+
+        public async Task<IEnumerable<(string secondaryKey, T data)>> GetDrafts<T>(string key) where T : class
+        {
+            Guard.ArgumentNotEmptyString(key, nameof(key));
+
+            try
+            {
+                var result = await connection.Table<Draft>().Where(x => x.Key == key)
+                    .ToListAsync()
+                    .ConfigureAwait(false);
+
+                return result.Select(x => (x.SecondaryKey, JsonConvert.DeserializeObject<T>(x.Data)));
+            }
+            catch (Exception ex)
+            {
+                log.Error(ex, "Failed to load message drafts into {Type}", typeof(T));
+            }
+
+            return null;
+        }
+
+        public async Task UpdateDraft<T>(string key, string secondaryKey, T data) where T : class
+        {
+            Guard.ArgumentNotEmptyString(key, nameof(key));
+            Guard.ArgumentNotNull(secondaryKey, nameof(secondaryKey));
+
+            try
+            {
+                var row = new Draft
+                {
+                    Key = key,
+                    SecondaryKey = secondaryKey,
+                    Data = JsonConvert.SerializeObject(data),
+                };
+
+                await connection.InsertOrReplaceAsync(row).ConfigureAwait(false);
+            }
+            catch (Exception ex)
+            {
+                log.Error(ex, "Failed to update message draft");
+            }
+        }
+
+        public async Task DeleteDraft(string key, string secondaryKey)
+        {
+            Guard.ArgumentNotEmptyString(key, nameof(key));
+            Guard.ArgumentNotNull(secondaryKey, nameof(secondaryKey));
+
+            try
+            {
+                await connection.ExecuteAsync(
+                    "DELETE FROM Drafts WHERE Key=? AND SecondaryKey=?",
+                    key,
+                    secondaryKey).ConfigureAwait(false);
+            }
+            catch (Exception ex)
+            {
+                log.Error(ex, "Failed to update message draft");
+            }
+        }
+
+        [Table("Drafts")]
+        private class Draft
+        {
+            public string Key { get; set; }
+            public string SecondaryKey { get; set; }
+            public string Data { get; set; }
+        }
+    }
+}