public async Task WatchAsync(DotNetWatchContext context, CancellationToken cancellationToken)
{
var processSpec = context.ProcessSpec;
if (context.SuppressMSBuildIncrementalism)
{
_reporter.Verbose("MSBuild incremental optimizations suppressed.");
}
_reporter.Output("Hot reload enabled. For a list of supported edits, see https://aka.ms/dotnet/hot-reload. " +
"Press \"Ctrl + R\" to restart.");
while (true)
{
context.Iteration++;
for (var i = 0; i < _filters.Length; i++)
{
await _filters[i].ProcessAsync(context, cancellationToken);
}
// Reset for next run
context.RequiresMSBuildRevaluation = false;
processSpec.EnvironmentVariables["DOTNET_WATCH_ITERATION"] = (context.Iteration + 1).ToString(CultureInfo.InvariantCulture);
var fileSet = context.FileSet;
if (fileSet == null)
{
_reporter.Error("Failed to find a list of files to watch");
return;
}
if (!fileSet.Project.IsNetCoreApp60OrNewer())
{
_reporter.Error($"Hot reload based watching is only supported in .NET 6.0 or newer apps. Update the project's launchSettings.json to disable this feature.");
return;
}
if (cancellationToken.IsCancellationRequested)
{
return;
}
if (context.Iteration == 0)
{
ConfigureExecutable(context, processSpec);
}
using var currentRunCancellationSource = new CancellationTokenSource();
var forceReload = _console.ListenForForceReloadRequest();
using var combinedCancellationSource = CancellationTokenSource.CreateLinkedTokenSource(
cancellationToken,
currentRunCancellationSource.Token,
forceReload);
using var fileSetWatcher = new FileSetWatcher(fileSet, _reporter);
try
{
using var hotReload = new HotReload(_processRunner, _reporter);
await hotReload.InitializeAsync(context, cancellationToken);
var processTask = _processRunner.RunAsync(processSpec, combinedCancellationSource.Token);
var args = string.Join(" ", processSpec.Arguments);
_reporter.Verbose($"Running {processSpec.ShortDisplayName()} with the following arguments: {args}");
_reporter.Output("Started");
Task <FileItem?> fileSetTask;
Task finishedTask;
while (true)
{
fileSetTask = fileSetWatcher.GetChangedFileAsync(combinedCancellationSource.Token);
finishedTask = await Task.WhenAny(processTask, fileSetTask).WaitAsync(combinedCancellationSource.Token);
if (finishedTask != fileSetTask || fileSetTask.Result is not FileItem fileItem)
{
// The app exited.
break;
}
else
{
_reporter.Output($"File changed: {fileItem.FilePath}.");
var start = Stopwatch.GetTimestamp();
if (await hotReload.TryHandleFileChange(context, fileItem, combinedCancellationSource.Token))
{
var totalTime = TimeSpan.FromTicks(Stopwatch.GetTimestamp() - start);
_reporter.Output($"Hot reload of changes succeeded.");
_reporter.Verbose($"Hot reload applied in {totalTime.TotalMilliseconds}ms.");
}
else
{
_reporter.Verbose($"Unable to handle changes to {fileItem.FilePath}. Rebuilding the app.");
break;
}
}
}
// Regardless of the which task finished first, make sure everything is cancelled
// and wait for dotnet to exit. We don't want orphan processes
currentRunCancellationSource.Cancel();
await Task.WhenAll(processTask, fileSetTask);
if (processTask.Result != 0 && finishedTask == processTask && !cancellationToken.IsCancellationRequested)
{
// Only show this error message if the process exited non-zero due to a normal process exit.
// Don't show this if dotnet-watch killed the inner process due to file change or CTRL+C by the user
_reporter.Error($"Exited with error code {processTask.Result}");
}
else
{
_reporter.Output("Exited");
}
if (finishedTask == processTask)
{
// Process exited. Redo evaludation
context.RequiresMSBuildRevaluation = true;
// Now wait for a file to change before restarting process
context.ChangedFile = await fileSetWatcher.GetChangedFileAsync(cancellationToken, () => _reporter.Warn("Waiting for a file to change before restarting dotnet..."));
}
else
{
Debug.Assert(finishedTask == fileSetTask);
var changedFile = fileSetTask.Result;
context.ChangedFile = changedFile;
}
}
private async Task <int> MainInternalAsync(
IReporter reporter,
string project,
IReadOnlyList <string> args,
CancellationToken cancellationToken)
{
// TODO multiple projects should be easy enough to add here
string projectFile;
try
{
projectFile = MsBuildProjectFinder.FindMsBuildProject(_workingDirectory, project);
}
catch (FileNotFoundException ex)
{
reporter.Error(ex.Message);
return(1);
}
var isDefaultRunCommand = false;
if (args.Count == 1 && args[0] == "run")
{
isDefaultRunCommand = true;
}
else if (args.Count == 0)
{
isDefaultRunCommand = true;
args = new[] { "run" };
}
var watchOptions = DotNetWatchOptions.Default;
var fileSetFactory = new MsBuildFileSetFactory(reporter,
watchOptions,
projectFile,
waitOnError: true,
trace: false);
var processInfo = new ProcessSpec
{
Executable = DotnetMuxer.MuxerPath,
WorkingDirectory = Path.GetDirectoryName(projectFile),
Arguments = args,
EnvironmentVariables =
{
["DOTNET_WATCH"] = "1"
},
};
if (CommandLineOptions.IsPollingEnabled)
{
_reporter.Output("Polling file watcher is enabled");
}
var defaultProfile = LaunchSettingsProfile.ReadDefaultProfile(_workingDirectory, reporter);
var context = new DotNetWatchContext
{
ProcessSpec = processInfo,
Reporter = _reporter,
SuppressMSBuildIncrementalism = watchOptions.SuppressMSBuildIncrementalism,
DefaultLaunchSettingsProfile = defaultProfile,
};
if (isDefaultRunCommand && !string.IsNullOrEmpty(defaultProfile?.HotReloadProfile))
{
_reporter.Verbose($"Found HotReloadProfile={defaultProfile.HotReloadProfile}. Watching with hot-reload");
// We'll sue hot-reload based watching if
// a) watch was invoked with no args or with exactly one arg - the run command e.g. `dotnet watch` or `dotnet watch run`
// b) The launch profile supports hot-reload based watching.
// The watcher will complain if users configure this for runtimes that would not support it.
await using var watcher = new HotReloadDotNetWatcher(reporter, fileSetFactory, watchOptions, _console);
await watcher.WatchAsync(context, cancellationToken);
}
else
{
_reporter.Verbose("Did not find a HotReloadProfile or running a non-default command. Watching with legacy behavior.");
// We'll use the presence of a profile to decide if we're going to use the hot-reload based watching.
// The watcher will complain if users configure this for runtimes that would not support it.
await using var watcher = new DotNetWatcher(reporter, fileSetFactory, watchOptions);
await watcher.WatchAsync(context, cancellationToken);
}
return(0);
}
public async Task WatchAsync(DotNetWatchContext context, CancellationToken cancellationToken)
{
var cancelledTaskSource = new TaskCompletionSource();
cancellationToken.Register(state => ((TaskCompletionSource)state).TrySetResult(),
cancelledTaskSource);
var processSpec = context.ProcessSpec;
var initialArguments = processSpec.Arguments.ToArray();
if (context.SuppressMSBuildIncrementalism)
{
_reporter.Verbose("MSBuild incremental optimizations suppressed.");
}
while (true)
{
context.Iteration++;
// Reset arguments
processSpec.Arguments = initialArguments;
for (var i = 0; i < _filters.Length; i++)
{
await _filters[i].ProcessAsync(context, cancellationToken);
}
// Reset for next run
context.RequiresMSBuildRevaluation = false;
processSpec.EnvironmentVariables["DOTNET_WATCH_ITERATION"] = (context.Iteration + 1).ToString(CultureInfo.InvariantCulture);
var fileSet = context.FileSet;
if (fileSet == null)
{
_reporter.Error("Failed to find a list of files to watch");
return;
}
if (cancellationToken.IsCancellationRequested)
{
return;
}
using (var currentRunCancellationSource = new CancellationTokenSource())
using (var combinedCancellationSource = CancellationTokenSource.CreateLinkedTokenSource(
cancellationToken,
currentRunCancellationSource.Token))
using (var fileSetWatcher = new FileSetWatcher(fileSet, _reporter))
{
var processTask = _processRunner.RunAsync(processSpec, combinedCancellationSource.Token);
var args = string.Join(" ", processSpec.Arguments);
_reporter.Verbose($"Running {processSpec.ShortDisplayName()} with the following arguments: {args}");
_reporter.Output("Started");
Task <FileItem?> fileSetTask;
Task finishedTask;
while (true)
{
fileSetTask = fileSetWatcher.GetChangedFileAsync(combinedCancellationSource.Token);
finishedTask = await Task.WhenAny(processTask, fileSetTask, cancelledTaskSource.Task);
if (finishedTask == fileSetTask &&
fileSetTask.Result is FileItem fileItem &&
await _staticFileHandler.TryHandleFileChange(context, fileItem, combinedCancellationSource.Token))
{
// We're able to handle the file change event without doing a full-rebuild.
}
public async Task WatchAsync(DotNetWatchContext context, CancellationToken cancellationToken)
{
var processSpec = context.ProcessSpec;
_reporter.Output("Hot reload enabled. For a list of supported edits, see https://aka.ms/dotnet/hot-reload. " +
"Press \"Ctrl + R\" to restart.");
var forceReload = new CancellationTokenSource();
_console.KeyPressed += (key) =>
{
var modifiers = ConsoleModifiers.Control;
if ((key.Modifiers & modifiers) == modifiers && key.Key == ConsoleKey.R)
{
var cancellationTokenSource = Interlocked.Exchange(ref forceReload, new CancellationTokenSource());
cancellationTokenSource.Cancel();
}
};
while (true)
{
context.Iteration++;
for (var i = 0; i < _filters.Length; i++)
{
await _filters[i].ProcessAsync(context, cancellationToken);
}
processSpec.EnvironmentVariables["DOTNET_WATCH_ITERATION"] = (context.Iteration + 1).ToString(CultureInfo.InvariantCulture);
var fileSet = context.FileSet;
if (fileSet == null)
{
_reporter.Error("Failed to find a list of files to watch");
return;
}
if (!fileSet.Project.IsNetCoreApp60OrNewer())
{
_reporter.Error($"Hot reload based watching is only supported in .NET 6.0 or newer apps. Update the project's launchSettings.json to disable this feature.");
return;
}
if (cancellationToken.IsCancellationRequested)
{
return;
}
if (context.Iteration == 0)
{
ConfigureExecutable(context, processSpec);
}
using var currentRunCancellationSource = new CancellationTokenSource();
using var combinedCancellationSource = CancellationTokenSource.CreateLinkedTokenSource(
cancellationToken,
currentRunCancellationSource.Token,
forceReload.Token);
using var fileSetWatcher = new HotReloadFileSetWatcher(fileSet, _reporter);
try
{
using var hotReload = new HotReload(_processRunner, _reporter);
await hotReload.InitializeAsync(context, cancellationToken);
var processTask = _processRunner.RunAsync(processSpec, combinedCancellationSource.Token);
var args = string.Join(" ", processSpec.Arguments);
_reporter.Verbose($"Running {processSpec.ShortDisplayName()} with the following arguments: {args}");
_reporter.Output("Started");
Task <FileItem[]> fileSetTask;
Task finishedTask;
while (true)
{
fileSetTask = fileSetWatcher.GetChangedFileAsync(combinedCancellationSource.Token);
finishedTask = await Task.WhenAny(processTask, fileSetTask).WaitAsync(combinedCancellationSource.Token);
if (finishedTask != fileSetTask || fileSetTask.Result is not FileItem[] fileItems)
{
// The app exited.
break;
}
else
{
if (MayRequireRecompilation(context, fileItems) is { } newFile)
{
_reporter.Output($"New file: {newFile.FilePath}. Rebuilding the application.");
break;
}
public async Task WatchAsync(ProcessSpec processSpec, CancellationToken cancellationToken)
{
Ensure.NotNull(processSpec, nameof(processSpec));
var cancelledTaskSource = new TaskCompletionSource();
cancellationToken.Register(state => ((TaskCompletionSource)state).TrySetResult(),
cancelledTaskSource);
var initialArguments = processSpec.Arguments.ToArray();
var context = new DotNetWatchContext
{
Iteration = -1,
ProcessSpec = processSpec,
Reporter = _reporter,
SuppressMSBuildIncrementalism = _dotnetWatchOptions.SuppressMSBuildIncrementalism,
};
if (context.SuppressMSBuildIncrementalism)
{
_reporter.Verbose("MSBuild incremental optimizations suppressed.");
}
while (true)
{
context.Iteration++;
// Reset arguments
processSpec.Arguments = initialArguments;
for (var i = 0; i < _filters.Length; i++)
{
await _filters[i].ProcessAsync(context, cancellationToken);
}
// Reset for next run
context.RequiresMSBuildRevaluation = false;
processSpec.EnvironmentVariables["DOTNET_WATCH_ITERATION"] = (context.Iteration + 1).ToString(CultureInfo.InvariantCulture);
var fileSet = context.FileSet;
if (fileSet == null)
{
_reporter.Error("Failed to find a list of files to watch");
return;
}
if (cancellationToken.IsCancellationRequested)
{
return;
}
using (var currentRunCancellationSource = new CancellationTokenSource())
using (var combinedCancellationSource = CancellationTokenSource.CreateLinkedTokenSource(
cancellationToken,
currentRunCancellationSource.Token))
using (var fileSetWatcher = new FileSetWatcher(fileSet, _reporter))
{
var processTask = _processRunner.RunAsync(processSpec, combinedCancellationSource.Token);
var args = ArgumentEscaper.EscapeAndConcatenate(processSpec.Arguments);
_reporter.Verbose($"Running {processSpec.ShortDisplayName()} with the following arguments: {args}");
_reporter.Output("Started");
Task <FileItem?> fileSetTask;
Task finishedTask;
while (true)
{
fileSetTask = fileSetWatcher.GetChangedFileAsync(combinedCancellationSource.Token);
finishedTask = await Task.WhenAny(processTask, fileSetTask, cancelledTaskSource.Task);
if (context.BrowserRefreshServer is not null &&
finishedTask == fileSetTask &&
fileSetTask.Result is FileItem {
FileKind : FileKind.StaticFile
} file)
{
_reporter.Verbose($"Handling file change event for static content {file.FilePath}.");
// If we can handle the file change without a browser refresh, do it.
await StaticContentHandler.TryHandleFileAction(context.BrowserRefreshServer, file, combinedCancellationSource.Token);
}
private async Task <int> MainInternalAsync(CommandLineOptions options, CancellationToken cancellationToken)
{
// TODO multiple projects should be easy enough to add here
string projectFile;
try
{
projectFile = MsBuildProjectFinder.FindMsBuildProject(_workingDirectory, options.Project);
}
catch (FileNotFoundException ex)
{
_reporter.Error(ex.Message);
return(1);
}
var args = options.RemainingArguments;
var isDefaultRunCommand = false;
if (args.Count == 1 && args[0] == "run")
{
isDefaultRunCommand = true;
}
else if (args.Count == 0)
{
isDefaultRunCommand = true;
args = new[] { "run" };
}
var watchOptions = DotNetWatchOptions.Default;
watchOptions.NonInteractive = options.NonInteractive;
var fileSetFactory = new MsBuildFileSetFactory(_reporter,
watchOptions,
projectFile,
waitOnError: true,
trace: false);
var processInfo = new ProcessSpec
{
Executable = DotnetMuxer.MuxerPath,
WorkingDirectory = Path.GetDirectoryName(projectFile),
Arguments = args,
EnvironmentVariables =
{
["DOTNET_WATCH"] = "1"
},
};
if (CommandLineOptions.IsPollingEnabled)
{
_reporter.Output("Polling file watcher is enabled");
}
var defaultProfile = LaunchSettingsProfile.ReadDefaultProfile(processInfo.WorkingDirectory, _reporter) ?? new();
var context = new DotNetWatchContext
{
ProcessSpec = processInfo,
Reporter = _reporter,
SuppressMSBuildIncrementalism = watchOptions.SuppressMSBuildIncrementalism,
DefaultLaunchSettingsProfile = defaultProfile,
};
context.ProjectGraph = TryReadProject(projectFile);
if (!options.NoHotReload && isDefaultRunCommand && context.ProjectGraph is not null && IsHotReloadSupported(context.ProjectGraph))
{
_reporter.Verbose($"Project supports hot reload and was configured to run with the default run-command. Watching with hot-reload");
// Use hot-reload based watching if
// a) watch was invoked with no args or with exactly one arg - the run command e.g. `dotnet watch` or `dotnet watch run`
// b) The launch profile supports hot-reload based watching.
// The watcher will complain if users configure this for runtimes that would not support it.
await using var watcher = new HotReloadDotNetWatcher(_reporter, _requester, fileSetFactory, watchOptions, _console, _workingDirectory);
await watcher.WatchAsync(context, cancellationToken);
}
public async Task WatchAsync(ProcessSpec processSpec, CancellationToken cancellationToken)
{
Ensure.NotNull(processSpec, nameof(processSpec));
var cancelledTaskSource = new TaskCompletionSource();
cancellationToken.Register(state => ((TaskCompletionSource)state).TrySetResult(),
cancelledTaskSource);
var initialArguments = processSpec.Arguments.ToArray();
var suppressMSBuildIncrementalism = Environment.GetEnvironmentVariable("DOTNET_WATCH_SUPPRESS_MSBUILD_INCREMENTALISM");
var context = new DotNetWatchContext
{
Iteration = -1,
ProcessSpec = processSpec,
Reporter = _reporter,
SuppressMSBuildIncrementalism = suppressMSBuildIncrementalism == "1" || suppressMSBuildIncrementalism == "true",
};
if (context.SuppressMSBuildIncrementalism)
{
_reporter.Verbose("MSBuild incremental optimizations suppressed.");
}
while (true)
{
context.Iteration++;
// Reset arguments
processSpec.Arguments = initialArguments;
for (var i = 0; i < _filters.Length; i++)
{
await _filters[i].ProcessAsync(context, cancellationToken);
}
// Reset for next run
context.RequiresMSBuildRevaluation = false;
processSpec.EnvironmentVariables["DOTNET_WATCH_ITERATION"] = (context.Iteration + 1).ToString(CultureInfo.InvariantCulture);
var fileSet = context.FileSet;
if (fileSet == null)
{
_reporter.Error("Failed to find a list of files to watch");
return;
}
if (cancellationToken.IsCancellationRequested)
{
return;
}
using (var currentRunCancellationSource = new CancellationTokenSource())
using (var combinedCancellationSource = CancellationTokenSource.CreateLinkedTokenSource(
cancellationToken,
currentRunCancellationSource.Token))
using (var fileSetWatcher = new FileSetWatcher(fileSet, _reporter))
{
var fileSetTask = fileSetWatcher.GetChangedFileAsync(combinedCancellationSource.Token);
var processTask = _processRunner.RunAsync(processSpec, combinedCancellationSource.Token);
var args = ArgumentEscaper.EscapeAndConcatenate(processSpec.Arguments);
_reporter.Verbose($"Running {processSpec.ShortDisplayName()} with the following arguments: {args}");
_reporter.Output("Started");
var finishedTask = await Task.WhenAny(processTask, fileSetTask, cancelledTaskSource.Task);
// Regardless of the which task finished first, make sure everything is cancelled
// and wait for dotnet to exit. We don't want orphan processes
currentRunCancellationSource.Cancel();
await Task.WhenAll(processTask, fileSetTask);
if (processTask.Result != 0 && finishedTask == processTask && !cancellationToken.IsCancellationRequested)
{
// Only show this error message if the process exited non-zero due to a normal process exit.
// Don't show this if dotnet-watch killed the inner process due to file change or CTRL+C by the user
_reporter.Error($"Exited with error code {processTask.Result}");
}
else
{
_reporter.Output("Exited");
}
if (finishedTask == cancelledTaskSource.Task || cancellationToken.IsCancellationRequested)
{
return;
}
context.ChangedFile = fileSetTask.Result;
if (finishedTask == processTask)
{
// Process exited. Redo evaludation
context.RequiresMSBuildRevaluation = true;
// Now wait for a file to change before restarting process
context.ChangedFile = await fileSetWatcher.GetChangedFileAsync(cancellationToken, () => _reporter.Warn("Waiting for a file to change before restarting dotnet..."));
}
if (!string.IsNullOrEmpty(fileSetTask.Result))
{
_reporter.Output($"File changed: {fileSetTask.Result}");
}
}
}
}
public async Task WatchAsync(DotNetWatchContext context, CancellationToken cancellationToken)
{
var processSpec = context.ProcessSpec;
var forceReload = new CancellationTokenSource();
var hotReloadEnabledMessage = "Hot reload enabled. For a list of supported edits, see https://aka.ms/dotnet/hot-reload.";
if (!_dotNetWatchOptions.NonInteractive)
{
_reporter.Output($"{hotReloadEnabledMessage}{Environment.NewLine} {(_dotNetWatchOptions.SuppressEmojis ? string.Empty : "💡")} Press \"Ctrl + R\" to restart.", emoji: "🔥");
_console.KeyPressed += (key) =>
{
var modifiers = ConsoleModifiers.Control;
if ((key.Modifiers & modifiers) == modifiers && key.Key == ConsoleKey.R)
{
var cancellationTokenSource = Interlocked.Exchange(ref forceReload, new CancellationTokenSource());
cancellationTokenSource.Cancel();
}
};
}
else
{
_reporter.Output(hotReloadEnabledMessage, emoji: "🔥");
}
while (true)
{
context.Iteration++;
for (var i = 0; i < _filters.Length; i++)
{
await _filters[i].ProcessAsync(context, cancellationToken);
}
processSpec.EnvironmentVariables["DOTNET_WATCH_ITERATION"] = (context.Iteration + 1).ToString(CultureInfo.InvariantCulture);
var fileSet = context.FileSet;
if (fileSet == null)
{
_reporter.Error("Failed to find a list of files to watch");
return;
}
if (!fileSet.Project.IsNetCoreApp60OrNewer())
{
_reporter.Error($"Hot reload based watching is only supported in .NET 6.0 or newer apps. Update the project's launchSettings.json to disable this feature.");
return;
}
if (cancellationToken.IsCancellationRequested)
{
return;
}
if (context.Iteration == 0)
{
ConfigureExecutable(context, processSpec);
}
using var currentRunCancellationSource = new CancellationTokenSource();
using var combinedCancellationSource = CancellationTokenSource.CreateLinkedTokenSource(
cancellationToken,
currentRunCancellationSource.Token,
forceReload.Token);
using var fileSetWatcher = new HotReloadFileSetWatcher(fileSet, _reporter);
try
{
using var hotReload = new HotReload(_processRunner, _reporter);
await hotReload.InitializeAsync(context, cancellationToken);
var processTask = _processRunner.RunAsync(processSpec, combinedCancellationSource.Token);
var args = string.Join(" ", processSpec.Arguments);
_reporter.Verbose($"Running {processSpec.ShortDisplayName()} with the following arguments: {args}");
_reporter.Output("Started", emoji: "🚀");
Task <FileItem[]?> fileSetTask;
Task finishedTask;
while (true)
{
fileSetTask = fileSetWatcher.GetChangedFileAsync(combinedCancellationSource.Token);
finishedTask = await Task.WhenAny(processTask, fileSetTask).WaitAsync(combinedCancellationSource.Token);
if (finishedTask != fileSetTask || fileSetTask.Result is not FileItem[] fileItems)
{
if (processTask.IsFaulted && finishedTask == processTask && !cancellationToken.IsCancellationRequested)
{
// Only show this error message if the process exited non-zero due to a normal process exit.
// Don't show this if dotnet-watch killed the inner process due to file change or CTRL+C by the user
_reporter.Error($"Application failed to start: {processTask.Exception?.InnerException?.Message}");
}
break;
}
else
{
if (MayRequireRecompilation(context, fileItems) is { } newFile)
{
_reporter.Output($"New file: {GetRelativeFilePath(newFile.FilePath)}. Rebuilding the application.");
break;
}
