Merge pull request #150 from MaceWindu/error-handling

Small QoL improvements around WebSocket connection
Sicos1977 · Apr 3, 2024 · 084d724 · 084d724
2 parents 48fbc43 + 548c63a
commit 084d724
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Showing 3 changed files with 47 additions and 7 deletions.
diff --git a/ChromiumHtmlToPdfLib/Browser.cs b/ChromiumHtmlToPdfLib/Browser.cs
@@ -695,7 +695,7 @@ public async Task RunJavascriptAsync(string script, CancellationToken cancellati
 
         var printToPdfResponse = PrintToPdfResponse.FromJson(result);
 
-        if (string.IsNullOrEmpty(printToPdfResponse.Result.Stream))
+        if (printToPdfResponse.Error != null || string.IsNullOrEmpty(printToPdfResponse.Result?.Stream))
             throw new ConversionException($"Conversion failed ... did not get the expected response from Chromium, response '{result}'");
 
         if (!outputStream.CanWrite)
@@ -704,7 +704,7 @@ public async Task RunJavascriptAsync(string script, CancellationToken cancellati
         _logger?.Info("Resetting output stream to position 0");
 
         message = new Message { Method = "IO.read" };
-        message.AddParameter("handle", printToPdfResponse.Result.Stream!);
+        message.AddParameter("handle", printToPdfResponse.Result!.Stream!);
         message.AddParameter("size", 1048576); // Get the pdf in chunks of 1MB
 
         _logger?.Info("Reading generated PDF from IO stream with handle id {stream}", printToPdfResponse.Result.Stream);

diff --git a/ChromiumHtmlToPdfLib/Connection.cs b/ChromiumHtmlToPdfLib/Connection.cs
@@ -92,6 +92,11 @@ public class Connection : IDisposable, IAsyncDisposable
     /// </summary>
     private readonly int _timeout;
 
+    /// <summary>
+    /// Task to await for <see cref="ReceiveLoop"/> completion.
+    /// </summary>
+    private readonly Task<Task> _receiveTask;
+
     /// <summary>
     ///     Keeps track is we already disposed our resources
     /// </summary>
@@ -114,7 +119,7 @@ internal Connection(string url, int timeout, Logger? logger)
         _webSocket = new ClientWebSocket();
         _receiveLoopCts = new CancellationTokenSource();
         OpenWebSocketAsync().GetAwaiter().GetResult();
-        Task.Factory.StartNew(ReceiveLoop, new ReceiveLoopState(_logger, _webSocket, OnMessageReceived, _receiveLoopCts.Token), _receiveLoopCts.Token, TaskCreationOptions.LongRunning, TaskScheduler.Default);
+        _receiveTask = Task.Factory.StartNew(ReceiveLoop, new ReceiveLoopState(_logger, _webSocket, OnMessageReceived, _receiveLoopCts.Token), _receiveLoopCts.Token, TaskCreationOptions.LongRunning, TaskScheduler.Default);
     }
     #endregion
 
@@ -160,6 +165,10 @@ private static async Task ReceiveLoop(object? stateData)
         {
             // Ignore
         }
+        catch (WebSocketException wsex) when (wsex.Message == "The remote party closed the WebSocket connection without completing the close handshake.")
+        {
+            // Ignore
+        }
         catch (Exception exception)
         {
             WebSocketOnError(state.Logger, new ErrorEventArgs(exception));
@@ -333,6 +342,8 @@ public async Task InternalDisposeAsync()
 
         _receiveLoopCts.Cancel();
 
+        await (await _receiveTask.ConfigureAwait(false)).ConfigureAwait(false);
+
         _logger?.Info("Disposing websocket connection to url '{url}'", _url);
 
         if (_webSocket.State == WebSocketState.Open)
@@ -346,7 +357,7 @@ public async Task InternalDisposeAsync()
             }
             catch (Exception exception)
             {
-                _logger?.Error("An error occurred while closing the web socket, error: '{error}'", ExceptionHelpers.GetInnerException(exception));
+                _logger?.Error(exception, "An error occurred while closing the web socket, error: '{error}'", ExceptionHelpers.GetInnerException(exception));
             }
 
             _logger?.Info("Websocket connection closed");

diff --git a/ChromiumHtmlToPdfLib/Protocol/PrintToPdfResponse.cs b/ChromiumHtmlToPdfLib/Protocol/PrintToPdfResponse.cs
@@ -35,16 +35,25 @@ namespace ChromiumHtmlToPdfLib.Protocol;
 internal class PrintToPdfResponse
 {
     #region Properties
+    [JsonProperty("id")]
+    public int Id { get; set; }
+
     /// <summary>
     ///     <see cref="PrintToPdfResult" />
     /// </summary>
     [JsonProperty("result")]
-    public PrintToPdfResult Result { get; set; } = null!;
+    public PrintToPdfResult? Result { get; set; }
+
+    /// <summary>
+    ///     <see cref="PrintToPdfErrorResult" />
+    /// </summary>
+    [JsonProperty("error")]
+    public PrintToPdfErrorResult? Error { get; set; }
 
     /// <summary>
     ///     Returns <see cref="PrintToPdfResult.Data" /> as array of bytes
     /// </summary>
-    public byte[] Bytes => Convert.FromBase64String(Result.Data);
+    public byte[]? Bytes => Result != null ? Convert.FromBase64String(Result.Data) : null;
     #endregion
 
     #region FromJson
@@ -78,4 +87,24 @@ internal class PrintToPdfResult
     [JsonProperty("stream")]
     public string? Stream { get; set; }
     #endregion
-}
+}
+
+/// <summary>
+///     Error result returned from the <see cref="Converter" /> ConvertToPdf  method
+/// </summary>
+internal class PrintToPdfErrorResult
+{
+    #region Properties
+    /// <summary>
+    ///     Error code
+    /// </summary>
+    [JsonProperty("code")]
+    public int Code { get; set; }
+
+    /// <summary>
+    ///     Error message
+    /// </summary>
+    [JsonProperty("message")]
+    public string? Message { get; set; }
+    #endregion
+}