Add tests for EncoderValidator

* Add support for ffmpeg 4.2
* Parse the complete ffmpeg version instead of only the first 2 digits
* Make max and min version optional
* Remove max limitation (for now)
* Style improvements

MediaBrowser.MediaEncoding/Encoder/EncoderValidator.cs

@@ -1,173 +1,16 @@
 using System;
 using System.Collections.Generic;
-using System.Collections.ObjectModel;
+using System.Diagnostics;
 using System.Linq;
+using System.Text;
 using System.Text.RegularExpressions;
-using MediaBrowser.Model.Diagnostics;
 using Microsoft.Extensions.Logging;
 
 namespace MediaBrowser.MediaEncoding.Encoder
 {
     public class EncoderValidator
     {
-        private readonly ILogger _logger;
+        private const string DefaultEncoderPath = "ffmpeg";
-        private readonly IProcessFactory _processFactory;
-
-        public EncoderValidator(ILogger logger, IProcessFactory processFactory)
-        {
-            _logger = logger;
-            _processFactory = processFactory;
-        }
-
-        public (IEnumerable<string> decoders, IEnumerable<string> encoders) GetAvailableCoders(string encoderPath)
-        {
-            _logger.LogInformation("Validating media encoder at {EncoderPath}", encoderPath);
-
-            var decoders = GetCodecs(encoderPath, Codec.Decoder);
-            var encoders = GetCodecs(encoderPath, Codec.Encoder);
-
-            _logger.LogInformation("Encoder validation complete");
-
-            return (decoders, encoders);
-        }
-
-        public bool ValidateVersion(string encoderAppPath, bool logOutput)
-        {
-            string output = null;
-            try
-            {
-                output = GetProcessOutput(encoderAppPath, "-version");
-            }
-            catch (Exception ex)
-            {
-                if (logOutput)
-                {
-                    _logger.LogError(ex, "Error validating encoder");
-                }
-            }
-
-            if (string.IsNullOrWhiteSpace(output))
-            {
-                if (logOutput)
-                {
-                    _logger.LogError("FFmpeg validation: The process returned no result");
-                }
-                return false;
-            }
-
-            _logger.LogDebug("ffmpeg output: {Output}", output);
-
-            if (output.IndexOf("Libav developers", StringComparison.OrdinalIgnoreCase) != -1)
-            {
-                if (logOutput)
-                {
-                    _logger.LogError("FFmpeg validation: avconv instead of ffmpeg is not supported");
-                }
-                return false;
-            }
-
-            // The min and max FFmpeg versions required to run jellyfin successfully
-            var minRequired = new Version(4, 0);
-            var maxRequired = new Version(4, 0);
-
-            // Work out what the version under test is
-            var underTest = GetFFmpegVersion(output);
-
-            if (logOutput)
-            {
-                _logger.LogInformation("FFmpeg validation: Found ffmpeg version {0}", underTest != null ? underTest.ToString() : "unknown");
-
-                if (underTest == null) // Version is unknown
-                {
-                    if (minRequired.Equals(maxRequired))
-                    {
-                        _logger.LogWarning("FFmpeg validation: We recommend ffmpeg version {0}", minRequired.ToString());
-                    }
-                    else
-                    {
-                        _logger.LogWarning("FFmpeg validation: We recommend a minimum of {0} and maximum of {1}", minRequired.ToString(), maxRequired.ToString());
-                    }
-                }
-                else if (underTest.CompareTo(minRequired) < 0) // Version is below what we recommend
-                {
-                    _logger.LogWarning("FFmpeg validation: The minimum recommended ffmpeg version is {0}", minRequired.ToString());
-                }
-                else if (underTest.CompareTo(maxRequired) > 0) // Version is above what we recommend
-                {
-                    _logger.LogWarning("FFmpeg validation: The maximum recommended ffmpeg version is {0}", maxRequired.ToString());
-                }
-                else  // Version is ok
-                {
-                    _logger.LogInformation("FFmpeg validation: Found suitable ffmpeg version");
-                }
-            }
-
-            // underTest shall be null if versions is unknown
-            return (underTest == null) ? false : (underTest.CompareTo(minRequired) >= 0 && underTest.CompareTo(maxRequired) <= 0);
-        }
-
-        /// <summary>
-        /// Using the output from "ffmpeg -version" work out the FFmpeg version.
-        /// For pre-built binaries the first line should contain a string like "ffmpeg version x.y", which is easy
-        /// to parse.  If this is not available, then we try to match known library versions to FFmpeg versions.
-        /// If that fails then we use one of the main libraries to determine if it's new/older than the latest
-        /// we have stored.
-        /// </summary>
-        /// <param name="output"></param>
-        /// <returns></returns>
-        static private Version GetFFmpegVersion(string output)
-        {
-            // For pre-built binaries the FFmpeg version should be mentioned at the very start of the output
-            var match = Regex.Match(output, @"ffmpeg version (\d+\.\d+)");
-
-            if (match.Success)
-            {
-                return new Version(match.Groups[1].Value);
-            }
-            else
-            {
-                // Try and use the individual library versions to determine a FFmpeg version
-                // This lookup table is to be maintained with the following command line:
-                // $ ./ffmpeg.exe -version | perl -ne ' print "$1=$2.$3," if /^(lib\w+)\s+(\d+)\.\s*(\d+)/'
-                var lut = new ReadOnlyDictionary<Version, string>
-                    (new Dictionary<Version, string>
-                    {
-                        { new Version("4.1"), "libavutil=56.22,libavcodec=58.35,libavformat=58.20,libavdevice=58.5,libavfilter=7.40,libswscale=5.3,libswresample=3.3,libpostproc=55.3," },
-                        { new Version("4.0"), "libavutil=56.14,libavcodec=58.18,libavformat=58.12,libavdevice=58.3,libavfilter=7.16,libswscale=5.1,libswresample=3.1,libpostproc=55.1," },
-                        { new Version("3.4"), "libavutil=55.78,libavcodec=57.107,libavformat=57.83,libavdevice=57.10,libavfilter=6.107,libswscale=4.8,libswresample=2.9,libpostproc=54.7," },
-                        { new Version("3.3"), "libavutil=55.58,libavcodec=57.89,libavformat=57.71,libavdevice=57.6,libavfilter=6.82,libswscale=4.6,libswresample=2.7,libpostproc=54.5," },
-                        { new Version("3.2"), "libavutil=55.34,libavcodec=57.64,libavformat=57.56,libavdevice=57.1,libavfilter=6.65,libswscale=4.2,libswresample=2.3,libpostproc=54.1," },
-                        { new Version("2.8"), "libavutil=54.31,libavcodec=56.60,libavformat=56.40,libavdevice=56.4,libavfilter=5.40,libswscale=3.1,libswresample=1.2,libpostproc=53.3," }
-                    });
-
-                // Create a reduced version string and lookup key from dictionary
-                var reducedVersion = GetVersionString(output);
-
-                // Try to lookup the string and return Key, otherwise if not found returns null
-                return lut.FirstOrDefault(x => x.Value == reducedVersion).Key;
-            }
-        }
-
-        /// <summary>
-        /// Grabs the library names and major.minor version numbers from the 'ffmpeg -version' output
-        /// and condenses them on to one line.  Output format is "name1=major.minor,name2=major.minor,etc."
-        /// </summary>
-        /// <param name="output"></param>
-        /// <returns></returns>
-        static private string GetVersionString(string output)
-        {
-            string pattern = @"((?<name>lib\w+)\s+(?<major>\d+)\.\s*(?<minor>\d+))";
-            RegexOptions options = RegexOptions.Multiline;
-
-            string rc = null;
-
-            foreach (Match m in Regex.Matches(output, pattern, options))
-            {
-                rc += string.Concat(m.Groups["name"], '=', m.Groups["major"], '.', m.Groups["minor"], ',');
-            }
-
-            return rc;
-        }
 
         private static readonly string[] requiredDecoders = new[]
         {
@@ -211,19 +54,167 @@ namespace MediaBrowser.MediaEncoding.Encoder
             "ac3"
         };
 
+        // Try and use the individual library versions to determine a FFmpeg version
+        // This lookup table is to be maintained with the following command line:
+        // $ ffmpeg -version | perl -ne ' print "$1=$2.$3," if /^(lib\w+)\s+(\d+)\.\s*(\d+)/'
+        private static readonly IReadOnlyDictionary<string, Version> _ffmpegVersionMap = new Dictionary<string, Version>
+        {
+            { "libavutil=56.31,libavcodec=58.54,libavformat=58.29,libavdevice=58.8,libavfilter=7.57,libswscale=5.5,libswresample=3.5,libpostproc=55.5,", new Version(4, 2) },
+            { "libavutil=56.22,libavcodec=58.35,libavformat=58.20,libavdevice=58.5,libavfilter=7.40,libswscale=5.3,libswresample=3.3,libpostproc=55.3,", new Version(4, 1) },
+            { "libavutil=56.14,libavcodec=58.18,libavformat=58.12,libavdevice=58.3,libavfilter=7.16,libswscale=5.1,libswresample=3.1,libpostproc=55.1,", new Version(4, 0) },
+            { "libavutil=55.78,libavcodec=57.107,libavformat=57.83,libavdevice=57.10,libavfilter=6.107,libswscale=4.8,libswresample=2.9,libpostproc=54.7,", new Version(3, 4) },
+            { "libavutil=55.58,libavcodec=57.89,libavformat=57.71,libavdevice=57.6,libavfilter=6.82,libswscale=4.6,libswresample=2.7,libpostproc=54.5,", new Version(3, 3) },
+            { "libavutil=55.34,libavcodec=57.64,libavformat=57.56,libavdevice=57.1,libavfilter=6.65,libswscale=4.2,libswresample=2.3,libpostproc=54.1,", new Version(3, 2) },
+            { "libavutil=54.31,libavcodec=56.60,libavformat=56.40,libavdevice=56.4,libavfilter=5.40,libswscale=3.1,libswresample=1.2,libpostproc=53.3,", new Version(2, 8) }
+        };
+
+        private readonly ILogger _logger;
+
+        private readonly string _encoderPath;
+
+        public EncoderValidator(ILogger logger, string encoderPath = DefaultEncoderPath)
+        {
+            _logger = logger;
+            _encoderPath = encoderPath;
+        }
+
+        public static Version MinVersion { get; } = new Version(4, 0);
+
+        public static Version MaxVersion { get; } = null;
+
+        public bool ValidateVersion()
+        {
+            string output = null;
+            try
+            {
+                output = GetProcessOutput(_encoderPath, "-version");
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error validating encoder");
+            }
+
+            if (string.IsNullOrWhiteSpace(output))
+            {
+                _logger.LogError("FFmpeg validation: The process returned no result");
+                return false;
+            }
+
+            _logger.LogDebug("ffmpeg output: {Output}", output);
+
+            return ValidateVersionInternal(output);
+        }
+
+        internal bool ValidateVersionInternal(string versionOutput)
+        {
+            if (versionOutput.IndexOf("Libav developers", StringComparison.OrdinalIgnoreCase) != -1)
+            {
+                _logger.LogError("FFmpeg validation: avconv instead of ffmpeg is not supported");
+                return false;
+            }
+
+            // Work out what the version under test is
+            var version = GetFFmpegVersion(versionOutput);
+
+            _logger.LogInformation("Found ffmpeg version {0}", version != null ? version.ToString() : "unknown");
+
+            if (version == null && MinVersion != null && MaxVersion != null) // Version is unknown
+            {
+                if (MinVersion == MaxVersion)
+                {
+                    _logger.LogWarning("FFmpeg validation: We recommend ffmpeg version {0}", MinVersion);
+                }
+                else
+                {
+                    _logger.LogWarning("FFmpeg validation: We recommend a minimum of {0} and maximum of {1}", MinVersion, MaxVersion);
+                }
+
+                return false;
+            }
+            else if (MinVersion != null && version < MinVersion) // Version is below what we recommend
+            {
+                _logger.LogWarning("FFmpeg validation: The minimum recommended ffmpeg version is {0}", MinVersion);
+                return false;
+            }
+            else if (MaxVersion != null && version > MaxVersion) // Version is above what we recommend
+            {
+                _logger.LogWarning("FFmpeg validation: The maximum recommended ffmpeg version is {0}", MaxVersion);
+                return false;
+            }
+
+            return true;
+        }
+
+        public IEnumerable<string> GetDecoders() => GetCodecs(Codec.Decoder);
+
+        public IEnumerable<string> GetEncoders() => GetCodecs(Codec.Encoder);
+
+        /// <summary>
+        /// Using the output from "ffmpeg -version" work out the FFmpeg version.
+        /// For pre-built binaries the first line should contain a string like "ffmpeg version x.y", which is easy
+        /// to parse.  If this is not available, then we try to match known library versions to FFmpeg versions.
+        /// If that fails then we use one of the main libraries to determine if it's new/older than the latest
+        /// we have stored.
+        /// </summary>
+        /// <param name="output"></param>
+        /// <returns></returns>
+        internal static Version GetFFmpegVersion(string output)
+        {
+            // For pre-built binaries the FFmpeg version should be mentioned at the very start of the output
+            var match = Regex.Match(output, @"ffmpeg version ((?:\d+\.?)+)");
+
+            if (match.Success)
+            {
+                return new Version(match.Groups[1].Value);
+            }
+            else
+            {
+                // Create a reduced version string and lookup key from dictionary
+                var reducedVersion = GetLibrariesVersionString(output);
+
+                // Try to lookup the string and return Key, otherwise if not found returns null
+                return _ffmpegVersionMap.TryGetValue(reducedVersion, out Version version) ? version : null;
+            }
+        }
+
+        /// <summary>
+        /// Grabs the library names and major.minor version numbers from the 'ffmpeg -version' output
+        /// and condenses them on to one line.  Output format is "name1=major.minor,name2=major.minor,etc."
+        /// </summary>
+        /// <param name="output"></param>
+        /// <returns></returns>
+        private static string GetLibrariesVersionString(string output)
+        {
+            var rc = new StringBuilder(144);
+            foreach (Match m in Regex.Matches(
+                output,
+                @"((?<name>lib\w+)\s+(?<major>\d+)\.\s*(?<minor>\d+))",
+                RegexOptions.Multiline))
+            {
+                rc.Append(m.Groups["name"])
+                    .Append('=')
+                    .Append(m.Groups["major"])
+                    .Append('.')
+                    .Append(m.Groups["minor"])
+                    .Append(',');
+            }
+
+            return rc.Length == 0 ? null : rc.ToString();
+        }
+
         private enum Codec
         {
             Encoder,
             Decoder
         }
 
-        private IEnumerable<string> GetCodecs(string encoderAppPath, Codec codec)
+        private IEnumerable<string> GetCodecs(Codec codec)
         {
             string codecstr = codec == Codec.Encoder ? "encoders" : "decoders";
             string output = null;
             try
             {
-                output = GetProcessOutput(encoderAppPath, "-" + codecstr);
+                output = GetProcessOutput(_encoderPath, "-" + codecstr);
             }
             catch (Exception ex)
             {
@@ -250,46 +241,26 @@ namespace MediaBrowser.MediaEncoding.Encoder
 
         private string GetProcessOutput(string path, string arguments)
         {
-            IProcess process = _processFactory.Create(new ProcessOptions
+            using (var process = new Process()
+            {
+                StartInfo = new ProcessStartInfo(path, arguments)
                 {
                     CreateNoWindow = true,
                     UseShellExecute = false,
-                FileName = path,
+                    WindowStyle = ProcessWindowStyle.Hidden,
-                Arguments = arguments,
-                IsHidden = true,
                     ErrorDialog = false,
                     RedirectStandardOutput = true,
                     // ffmpeg uses stderr to log info, don't show this
                     RedirectStandardError = true
-            });
+                }
-
+            })
+            {
                 _logger.LogDebug("Running {Path} {Arguments}", path, arguments);
 
-            using (process)
-            {
                 process.Start();
 
-                try
-                {
                 return process.StandardOutput.ReadToEnd();
             }
-                catch
-                {
-                    _logger.LogWarning("Killing process {Path} {Arguments}", path, arguments);
-
-                    // Hate having to do this
-                    try
-                    {
-                        process.Kill();
-                    }
-                    catch (Exception ex)
-                    {
-                        _logger.LogError(ex, "Error killing process");
-                    }
-
-                    throw;
-                }
-            }
         }
     }
 }

MediaBrowser.MediaEncoding/Encoder/MediaEncoder.cs

@@ -114,13 +114,13 @@ namespace MediaBrowser.MediaEncoding.Encoder
                 FFprobePath = Regex.Replace(FFmpegPath, @"[^\/\\]+?(\.[^\/\\\n.]+)?$", @"ffprobe$1");
 
                 // Interrogate to understand what coders are supported
-                var result = new EncoderValidator(_logger, _processFactory).GetAvailableCoders(FFmpegPath);
+                var validator = new EncoderValidator(_logger, FFmpegPath);
 
-                SetAvailableDecoders(result.decoders);
+                SetAvailableDecoders(validator.GetDecoders());
-                SetAvailableEncoders(result.encoders);
+                SetAvailableEncoders(validator.GetEncoders());
             }
 
-            _logger.LogInformation("FFmpeg: {0}: {1}", EncoderLocation.ToString(), FFmpegPath ?? string.Empty);
+            _logger.LogInformation("FFmpeg: {0}: {1}", EncoderLocation, FFmpegPath ?? string.Empty);
         }
 
         /// <summary>
@@ -183,11 +183,11 @@ namespace MediaBrowser.MediaEncoding.Encoder
             {
                 if (File.Exists(path))
                 {
-                    rc = new EncoderValidator(_logger, _processFactory).ValidateVersion(path, true);
+                    rc = new EncoderValidator(_logger, path).ValidateVersion();
 
                     if (!rc)
                     {
-                        _logger.LogWarning("FFmpeg: {0}: Failed version check: {1}", location.ToString(), path);
+                        _logger.LogWarning("FFmpeg: {0}: Failed version check: {1}", location, path);
                     }
 
                     // ToDo - Enable the ffmpeg validator.  At the moment any version can be used.
@@ -198,7 +198,7 @@ namespace MediaBrowser.MediaEncoding.Encoder
                 }
                 else
                 {
-                    _logger.LogWarning("FFmpeg: {0}: File not found: {1}", location.ToString(), path);
+                    _logger.LogWarning("FFmpeg: {0}: File not found: {1}", location, path);
                 }
             }
 
@@ -228,9 +228,9 @@ namespace MediaBrowser.MediaEncoding.Encoder
         /// </summary>
         /// <param name="fileName"></param>
         /// <returns></returns>
-        private string ExistsOnSystemPath(string filename)
+        private string ExistsOnSystemPath(string fileName)
         {
-            string inJellyfinPath = GetEncoderPathFromDirectory(System.AppContext.BaseDirectory, filename);
+            string inJellyfinPath = GetEncoderPathFromDirectory(System.AppContext.BaseDirectory, fileName);
             if (!string.IsNullOrEmpty(inJellyfinPath))
             {
                 return inJellyfinPath;
@@ -239,13 +239,14 @@ namespace MediaBrowser.MediaEncoding.Encoder
 
             foreach (var path in values.Split(Path.PathSeparator))
             {
-                var candidatePath = GetEncoderPathFromDirectory(path, filename);
+                var candidatePath = GetEncoderPathFromDirectory(path, fileName);
 
                 if (!string.IsNullOrEmpty(candidatePath))
                 {
                     return candidatePath;
                 }
             }
+
             return null;
         }
 

MediaBrowser.MediaEncoding/Properties/AssemblyInfo.cs

@@ -1,5 +1,6 @@
 using System.Reflection;
 using System.Resources;
+using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 
 // General Information about an assembly is controlled through the following
@@ -14,6 +15,7 @@ using System.Runtime.InteropServices;
 [assembly: AssemblyTrademark("")]
 [assembly: AssemblyCulture("")]
 [assembly: NeutralResourcesLanguage("en")]
+[assembly: InternalsVisibleTo("Jellyfin.MediaEncoding.Tests")]
 
 // Setting ComVisible to false makes the types in this assembly not visible
 // to COM components.  If you need to access a type in this assembly from

MediaBrowser.sln

@@ -57,6 +57,8 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "tests", "tests", "{FBBB5129
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Jellyfin.Common.Tests", "tests\Jellyfin.Common.Tests\Jellyfin.Common.Tests.csproj", "{DF194677-DFD3-42AF-9F75-D44D5A416478}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Jellyfin.MediaEncoding.Tests", "tests\Jellyfin.MediaEncoding.Tests\Jellyfin.MediaEncoding.Tests.csproj", "{28464062-0939-4AA7-9F7B-24DDDA61A7C0}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -159,6 +161,10 @@ Global
 		{DF194677-DFD3-42AF-9F75-D44D5A416478}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{DF194677-DFD3-42AF-9F75-D44D5A416478}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{DF194677-DFD3-42AF-9F75-D44D5A416478}.Release|Any CPU.Build.0 = Release|Any CPU
+		{28464062-0939-4AA7-9F7B-24DDDA61A7C0}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{28464062-0939-4AA7-9F7B-24DDDA61A7C0}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{28464062-0939-4AA7-9F7B-24DDDA61A7C0}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{28464062-0939-4AA7-9F7B-24DDDA61A7C0}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -186,5 +192,6 @@ Global
 	EndGlobalSection
 	GlobalSection(NestedProjects) = preSolution
 		{DF194677-DFD3-42AF-9F75-D44D5A416478} = {FBBB5129-006E-4AD7-BAD5-8B7CA1D10ED6}
+		{28464062-0939-4AA7-9F7B-24DDDA61A7C0} = {FBBB5129-006E-4AD7-BAD5-8B7CA1D10ED6}
 	EndGlobalSection
 EndGlobal

tests/Jellyfin.Common.Tests/Jellyfin.Common.Tests.csproj

@@ -2,14 +2,14 @@
 
   <PropertyGroup>
     <TargetFramework>netcoreapp2.2</TargetFramework>
-
     <IsPackable>false</IsPackable>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.2.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.3.0" />
     <PackageReference Include="xunit" Version="2.4.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.1" />
+    <PackageReference Include="coverlet.collector" Version="1.1.0" />
   </ItemGroup>
 
   <ItemGroup>

tests/Jellyfin.MediaEncoding.Tests/EncoderValidatorTests.cs

@@ -0,0 +1,39 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using MediaBrowser.MediaEncoding.Encoder;
+using Microsoft.Extensions.Logging.Abstractions;
+using Xunit;
+
+namespace Jellyfin.MediaEncoding.Tests
+{
+    public class EncoderValidatorTests
+    {
+        private class GetFFmpegVersionTestData : IEnumerable<object[]>
+        {
+            public IEnumerator<object[]> GetEnumerator()
+            {
+                yield return new object[] { EncoderValidatorTestsData.FFmpegV42Output, new Version(4, 2) };
+                yield return new object[] { EncoderValidatorTestsData.FFmpegV404Output, new Version(4, 0, 4) };
+            }
+
+            IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
+        }
+
+        [Theory]
+        [ClassData(typeof(GetFFmpegVersionTestData))]
+        public void GetFFmpegVersionTest(string versionOutput, Version version)
+        {
+            Assert.Equal(version, EncoderValidator.GetFFmpegVersion(versionOutput));
+        }
+
+        [Theory]
+        [InlineData(EncoderValidatorTestsData.FFmpegV42Output, true)]
+        [InlineData(EncoderValidatorTestsData.FFmpegV404Output, true)]
+        public void ValidateVersionInternalTest(string versionOutput, bool valid)
+        {
+            var val = new EncoderValidator(new NullLogger<EncoderValidatorTests>());
+            Assert.Equal(valid, val.ValidateVersionInternal(versionOutput));
+        }
+    }
+}

tests/Jellyfin.MediaEncoding.Tests/EncoderValidatorTestsData.cs

@@ -0,0 +1,31 @@
+namespace Jellyfin.MediaEncoding.Tests
+{
+    internal static class EncoderValidatorTestsData
+    {
+        public const string FFmpegV42Output = @"ffmpeg version n4.2 Copyright (c) 2000-2019 the FFmpeg developers
+built with gcc 9.1.0 (GCC)
+configuration: --prefix=/usr --disable-debug --disable-static --disable-stripping --enable-fontconfig --enable-gmp --enable-gnutls --enable-gpl --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libdav1d --enable-libdrm --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libiec61883 --enable-libjack --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libv4l2 --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxcb --enable-libxml2 --enable-libxvid --enable-nvdec --enable-nvenc --enable-omx --enable-shared --enable-version3
+libavutil      56. 31.100 / 56. 31.100
+libavcodec     58. 54.100 / 58. 54.100
+libavformat    58. 29.100 / 58. 29.100
+libavdevice    58.  8.100 / 58.  8.100
+libavfilter     7. 57.100 /  7. 57.100
+libswscale      5.  5.100 /  5.  5.100
+libswresample   3.  5.100 /  3.  5.100
+libpostproc    55.  5.100 / 55.  5.100
+";
+
+    public const string FFmpegV404Output = @"ffmpeg version 4.0.4 Copyright (c) 2000-2019 the FFmpeg developers
+built with gcc 8 (Debian 8.3.0-6)
+configuration: --toolchain=hardened --prefix=/usr --target-os=linux --enable-cross-compile --extra-cflags=--static --enable-gpl --enable-static --disable-doc --disable-ffplay --disable-shared --disable-libxcb --disable-sdl2 --disable-xlib --enable-libfontconfig --enable-fontconfig --enable-gmp --enable-gnutls --enable-libass --enable-libbluray --enable-libdrm --enable-libfreetype --enable-libfribidi --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libwebp --enable-libx264 --enable-libx265 --enable-libzvbi --enable-omx --enable-omx-rpi --enable-version3 --enable-vaapi --enable-vdpau --arch=amd64 --enable-nvenc --enable-nvdec
+libavutil      56. 14.100 / 56. 14.100
+libavcodec     58. 18.100 / 58. 18.100
+libavformat    58. 12.100 / 58. 12.100
+libavdevice    58.  3.100 / 58.  3.100
+libavfilter     7. 16.100 /  7. 16.100
+libswscale      5.  1.100 /  5.  1.100
+libswresample   3.  1.100 /  3.  1.100
+libpostproc    55.  1.100 / 55.  1.100
+";
+    }
+}

tests/Jellyfin.MediaEncoding.Tests/Jellyfin.MediaEncoding.Tests.csproj

@@ -0,0 +1,19 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp2.2</TargetFramework>
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.3.0" />
+    <PackageReference Include="xunit" Version="2.4.1" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.1" />
+    <PackageReference Include="coverlet.collector" Version="1.1.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="../../MediaBrowser.MediaEncoding/MediaBrowser.MediaEncoding.csproj" />
+  </ItemGroup>
+
+</Project>