add startup error handling

MediaBrowser.MediaEncoding/Encoder/EncoderValidator.cs

@@ -0,0 +1,159 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.IO;
+using MediaBrowser.Model.Logging;
+
+namespace MediaBrowser.MediaEncoding.Encoder
+{
+    public class EncoderValidator
+    {
+        private readonly ILogger _logger;
+
+        public EncoderValidator(ILogger logger)
+        {
+            _logger = logger;
+        }
+
+        public Tuple<List<string>, List<string>> Validate(string encoderPath)
+        {
+            _logger.Info("Validating media encoder at {0}", encoderPath);
+
+            var decoders = GetDecoders(encoderPath);
+            var encoders = GetEncoders(encoderPath);
+
+            _logger.Info("Encoder validation complete");
+
+            return new Tuple<List<string>, List<string>>(decoders, encoders);
+        }
+
+        private List<string> GetDecoders(string ffmpegPath)
+        {
+            string output = string.Empty;
+            try
+            {
+                output = GetFFMpegOutput(ffmpegPath, "-decoders");
+            }
+            catch
+            {
+            }
+            //_logger.Debug("ffmpeg decoder query result: {0}", output ?? string.Empty);
+
+            var found = new List<string>();
+            var required = new[]
+            {
+                "h264_qsv",
+                "mpeg2_qsv",
+                "vc1_qsv"
+            };
+
+            foreach (var codec in required)
+            {
+                var srch = " " + codec + "  ";
+
+                if (output.IndexOf(srch, StringComparison.OrdinalIgnoreCase) == -1)
+                {
+                    _logger.Warn("ffmpeg is missing decoder " + codec);
+                }
+                else
+                {
+                    found.Add(codec);
+                }
+            }
+
+            return found;
+        }
+
+        private List<string> GetEncoders(string ffmpegPath)
+        {
+            string output = null;
+            try
+            {
+                output = GetFFMpegOutput(ffmpegPath, "-encoders");
+            }
+            catch
+            {
+            }
+            //_logger.Debug("ffmpeg encoder query result: {0}", output ?? string.Empty);
+
+            var found = new List<string>();
+            var required = new[]
+            {
+                "libx264",
+                "libx265",
+                "mpeg4",
+                "msmpeg4",
+                //"libvpx",
+                //"libvpx-vp9",
+                "aac",
+                "libmp3lame",
+                "libopus",
+                //"libvorbis",
+                "srt"
+            };
+
+            foreach (var codec in required)
+            {
+                var srch = " " + codec + "  ";
+
+                if (output.IndexOf(srch, StringComparison.OrdinalIgnoreCase) == -1)
+                {
+                    _logger.Warn("ffmpeg is missing encoder " + codec);
+                }
+                else
+                {
+                    found.Add(codec);
+                }
+            }
+
+            return found;
+        }
+
+        private string GetFFMpegOutput(string path, string arguments)
+        {
+            var process = new Process
+            {
+                StartInfo = new ProcessStartInfo
+                {
+                    CreateNoWindow = true,
+                    UseShellExecute = false,
+                    FileName = path,
+                    Arguments = arguments,
+                    WindowStyle = ProcessWindowStyle.Hidden,
+                    ErrorDialog = false,
+                    RedirectStandardOutput = true,
+                    RedirectStandardError = true
+                }
+            };
+
+            using (process)
+            {
+                process.Start();
+
+                try
+                {
+                    process.BeginErrorReadLine();
+
+                    using (var reader = new StreamReader(process.StandardOutput.BaseStream))
+                    {
+                        return reader.ReadToEnd();
+                    }
+                }
+                catch
+                {
+                    // Hate having to do this
+                    try
+                    {
+                        process.Kill();
+                    }
+                    catch (Exception ex1)
+                    {
+                        _logger.ErrorException("Error killing ffmpeg", ex1);
+                    }
+
+                    throw;
+                }
+            }
+        }
+    }
+}