refactor(dotnet): dedupe collection repository queries

src/dotnet/QuantEngine.Infrastructure/Repositories/CollectionRepository.cs

@@ -17,11 +17,28 @@ namespace QuantEngine.Infrastructure.Repositories
             _connectionFactory = connectionFactory;
         }
 
+        private async Task ExecuteAsync(string sql, object? param = null)
+        {
+            using var conn = _connectionFactory.CreateConnection();
+            await conn.ExecuteAsync(sql, param);
+        }
+
+        private async Task<List<T>> QueryListAsync<T>(string sql, object? param = null)
+        {
+            using var conn = _connectionFactory.CreateConnection();
+            return (await conn.QueryAsync<T>(sql, param)).ToList();
+        }
+
+        private async Task<T?> QuerySingleOrDefaultAsync<T>(string sql, object? param = null)
+        {
+            using var conn = _connectionFactory.CreateConnection();
+            return await conn.QueryFirstOrDefaultAsync<T>(sql, param);
+        }
+
         public async Task SaveRunAsync(CollectionRunRecord run)
         {
             await EnsureTablesAsync();
-            using var conn = _connectionFactory.CreateConnection();
-            await conn.ExecuteAsync(@"
+            await ExecuteAsync(@"
                 INSERT INTO quantengine.kis_collection_runs (run_id, status, started_at, finished_at, total_snapshots, total_errors, updated_at)
                 VALUES (@RunId, @Status, @StartedAt, @FinishedAt, @TotalSnapshots, @TotalErrors, @UpdatedAt)
                 ON CONFLICT (run_id) DO UPDATE SET
@@ -36,8 +53,7 @@ namespace QuantEngine.Infrastructure.Repositories
 
         public async Task UpdateRunStatusAsync(string runId, string status, string? finishedAt = null, int? totalSnapshots = null, int? totalErrors = null)
         {
-            using var conn = _connectionFactory.CreateConnection();
-            await conn.ExecuteAsync(@"
+            await ExecuteAsync(@"
                 UPDATE quantengine.kis_collection_runs
                 SET status = @Status, finished_at = @FinishedAt, total_snapshots = @TotalSnapshots, total_errors = @TotalErrors, updated_at = @UpdatedAt
                 WHERE run_id = @RunId",
@@ -47,8 +63,7 @@ namespace QuantEngine.Infrastructure.Repositories
 
         public async Task SaveSnapshotAsync(CollectionSnapshotRecord snapshot)
         {
-            using var conn = _connectionFactory.CreateConnection();
-            await conn.ExecuteAsync(@"
+            await ExecuteAsync(@"
                 INSERT INTO quantengine.kis_collection_snapshots (run_id, dataset_name, ticker, source_name, payload_json, captured_at, created_at)
                 VALUES (@RunId, @DatasetName, @Ticker, @SourceName, @PayloadJson, @CapturedAt, @CreatedAt)
                 ON CONFLICT (run_id, ticker, source_name) DO UPDATE SET
@@ -60,8 +75,7 @@ namespace QuantEngine.Infrastructure.Repositories
 
         public async Task SaveErrorAsync(CollectionErrorRecord error)
         {
-            using var conn = _connectionFactory.CreateConnection();
-            await conn.ExecuteAsync(@"
+            await ExecuteAsync(@"
                 INSERT INTO quantengine.kis_collection_errors (run_id, source_name, error_kind, error_message, ticker, created_at)
                 VALUES (@RunId, @SourceName, @ErrorKind, @ErrorMessage, @Ticker, @CreatedAt)",
                 error
@@ -70,34 +84,31 @@ namespace QuantEngine.Infrastructure.Repositories
 
         public async Task<List<CollectionRunRecord>> GetRecentRunsAsync(int limit = 20)
         {
-            using var conn = _connectionFactory.CreateConnection();
-            return (await conn.QueryAsync<CollectionRunRecord>(@"
+            return await QueryListAsync<CollectionRunRecord>(@"
                 SELECT run_id as RunId, status, started_at as StartedAt, finished_at as FinishedAt,
                        total_snapshots as TotalSnapshots, total_errors as TotalErrors, updated_at as UpdatedAt
                 FROM quantengine.kis_collection_runs
                 ORDER BY started_at DESC
                 LIMIT @Limit",
                 new { Limit = limit }
-            )).ToList();
+            );
         }
 
         public async Task<List<CollectionSnapshotRecord>> GetRunSnapshotsAsync(string runId)
         {
-            using var conn = _connectionFactory.CreateConnection();
-            return (await conn.QueryAsync<CollectionSnapshotRecord>(@"
+            return await QueryListAsync<CollectionSnapshotRecord>(@"
                 SELECT run_id as RunId, dataset_name as DatasetName, ticker, source_name as SourceName,
                        payload_json as PayloadJson, captured_at as CapturedAt, created_at as CreatedAt
                 FROM quantengine.kis_collection_snapshots
                 WHERE run_id = @RunId
                 ORDER BY captured_at DESC",
                 new { RunId = runId }
-            )).ToList();
+            );
         }
 
         public async Task<List<CollectionErrorRecord>> GetRunErrorsAsync(string runId, int limit = 50)
         {
-            using var conn = _connectionFactory.CreateConnection();
-            return (await conn.QueryAsync<CollectionErrorRecord>(@"
+            return await QueryListAsync<CollectionErrorRecord>(@"
                 SELECT run_id as RunId, source_name as SourceName, error_kind as ErrorKind,
                        error_message as ErrorMessage, ticker as Ticker, created_at as CreatedAt
                 FROM quantengine.kis_collection_errors
@@ -105,32 +116,30 @@ namespace QuantEngine.Infrastructure.Repositories
                 ORDER BY created_at DESC
                 LIMIT @Limit",
                 new { RunId = runId, Limit = limit }
-            )).ToList();
+            );
         }
 
         public async Task<CollectionDashboardStateRecord> GetDashboardStateAsync()
         {
-            using var conn = _connectionFactory.CreateConnection();
-
-            var lastRun = await conn.QueryFirstOrDefaultAsync<CollectionRunRecord>(@"
+            var lastRun = await QuerySingleOrDefaultAsync<CollectionRunRecord>(@"
                 SELECT run_id as RunId, status, started_at as StartedAt, finished_at as FinishedAt,
                        total_snapshots as TotalSnapshots, total_errors as TotalErrors, updated_at as UpdatedAt
                 FROM quantengine.kis_collection_runs
                 ORDER BY started_at DESC
                 LIMIT 1");
 
-            var stats = await conn.QueryFirstOrDefaultAsync<dynamic>(@"
+            var stats = await QuerySingleOrDefaultAsync<dynamic>(@"
                 SELECT
                     COALESCE(SUM(total_snapshots), 0) as TotalSnapshots,
                     COALESCE(SUM(total_errors), 0) as TotalErrors
                 FROM quantengine.kis_collection_runs");
 
-            var recentErrors = (await conn.QueryAsync<CollectionErrorRecord>(@"
+            var recentErrors = await QueryListAsync<CollectionErrorRecord>(@"
                 SELECT run_id as RunId, source_name as SourceName, error_kind as ErrorKind,
                        error_message as ErrorMessage, ticker as Ticker, created_at as CreatedAt
                 FROM quantengine.kis_collection_errors
                 ORDER BY created_at DESC
-                LIMIT 5")).ToList();
+                LIMIT 5");
 
             return new CollectionDashboardStateRecord(
                 LastRunId: lastRun?.RunId,
@@ -144,8 +153,7 @@ namespace QuantEngine.Infrastructure.Repositories
 
         public async Task<List<CollectionSnapshotRecord>> GetLatestSnapshotsForTickerAsync(string ticker, int limit = 10)
         {
-            using var conn = _connectionFactory.CreateConnection();
-            return (await conn.QueryAsync<CollectionSnapshotRecord>(@"
+            return await QueryListAsync<CollectionSnapshotRecord>(@"
                 SELECT run_id as RunId, dataset_name as DatasetName, ticker, source_name as SourceName,
                        payload_json as PayloadJson, captured_at as CapturedAt, created_at as CreatedAt
                 FROM quantengine.kis_collection_snapshots
@@ -153,13 +161,12 @@ namespace QuantEngine.Infrastructure.Repositories
                 ORDER BY captured_at DESC
                 LIMIT @Limit",
                 new { Ticker = ticker, Limit = limit }
-            )).ToList();
+            );
         }
 
         public async Task SavePriceHistoryDailyAsync(PriceHistoryDailyRecord record)
         {
-            using var conn = _connectionFactory.CreateConnection();
-            await conn.ExecuteAsync(@"
+            await ExecuteAsync(@"
                 INSERT INTO quantengine.price_history_daily (ticker, trade_date, open, high, low, close, volume, source, provenance)
                 VALUES (@Ticker, @TradeDate, @Open, @High, @Low, @Close, @Volume, @Source, @Provenance::jsonb)
                 ON CONFLICT (ticker, trade_date) DO NOTHING",
@@ -182,20 +189,18 @@ namespace QuantEngine.Infrastructure.Repositories
 
         public async Task<List<PriceHistorySummaryRecord>> GetPriceHistorySummaryAsync()
         {
-            using var conn = _connectionFactory.CreateConnection();
-            return (await conn.QueryAsync<PriceHistorySummaryRecord>(@"
+            return await QueryListAsync<PriceHistorySummaryRecord>(@"
                 SELECT ticker AS Ticker, count(*)::int AS RowCount, min(trade_date) AS FirstDate, max(trade_date) AS LastDate
                 FROM quantengine.price_history_daily
                 GROUP BY ticker
                 ORDER BY ticker",
                 new { }
-            )).ToList();
+            );
         }
 
         private async Task EnsureTablesAsync()
         {
-            using var conn = _connectionFactory.CreateConnection();
-            await conn.ExecuteAsync(@"
+            await ExecuteAsync(@"
                 CREATE TABLE IF NOT EXISTS quantengine.kis_collection_runs (
                     run_id TEXT PRIMARY KEY,
                     status TEXT NOT NULL,