public void SaveBooks(IEnumerable <Book> books)
{
if (ReferenceEquals(books, null))
{
throw new ArgumentNullException();
}
try
{
using (var writer = new BinaryWriter(File.Open(FilePath, FileMode.OpenOrCreate, FileAccess.Write)))
{
foreach (var book in books)
{
writer.Write(book.Title);
writer.Write(book.Author);
writer.Write(book.ReleaseDate.ToString("d"));
writer.Write(book.Price);
}
}
logger.Trace($"Saved {books.Count()} books to {Environment.CurrentDirectory}'\'{FilePath}");
}
catch (IOException ex)
{
logger.Error($"error {ex.GetType()} in\n {ex.StackTrace}\n whith message {ex.Message}");
throw new Exception("Can't save data", ex);
}
}
static void LogError(Exception ex, string method, string attributeOrElementName)
{
if (logger == null)
{
throw ex;
}
#if DEBUG
logger.Error(method + ": Attribute or element: " + attributeOrElementName + ": " + ex.ToString());
#else
logger.Error(method + ": Attribute or element: " + attributeOrElementName + ": " + ex.Message);
#endif
}
public HttpResponseMessage UploadFile()
{
var statuses = new List <FilesStatus>();
try
{
//todo can we eliminate the HttpContext here
UploadWholeFile(HttpContextSource.Current, statuses);
}
catch (Exception exc)
{
Logger.Error(exc);
}
return(IframeSafeJson(statuses));
}
public virtual void LogException(Exception e)
{
if (!CanHandle(e))
{
throw new ArgumentException("ExceptionHandler has been asked to log exception of a type it does not handle!", e);
}
_logger.Error($"{_errorShortCode} - {e.Message}", e, _errorShortCode, e.Message);
}
/// <summary> Append one or more events to the stream. </summary>
/// <remarks>
/// Events are assigned consecutive sequence numbers. The FIRST of these
/// numbers is returned.
///
/// If no events are provided, return null.
///
/// If this object's state no longer represents the remote stream (because other
/// events have been written from elsewhere), this method will not write any
/// events and will return null. The caller should call <see cref="FetchAsync"/>
/// until it returns false to have the object catch up with remote state.
/// </remarks>
public async Task <uint?> WriteAsync(IReadOnlyList <TEvent> events, CancellationToken cancel = default(CancellationToken))
{
if (events.Count == 0)
{
return(null);
}
if (Position < _minimumWritePosition)
{
return(null);
}
if (events.Any(e => e == null))
{
throw new ArgumentException(@"No null events allowed", nameof(events));
}
var sw = Stopwatch.StartNew();
var rawEvents = events.Select((e, i) => new RawEvent(_lastSequence + (uint)(i + 1), _serializer.Serialize(e)))
.ToArray();
try
{
var result = await Storage.WriteAsync(Position, rawEvents, cancel);
_minimumWritePosition = result.NextPosition;
if (result.Success)
{
foreach (var e in rawEvents)
{
_cache.Enqueue(e);
}
Position = result.NextPosition;
var first = _lastSequence + 1;
_lastSequence += (uint)rawEvents.Length;
_log?.Debug(
$"Wrote {rawEvents.Length} events up to seq {_lastSequence} in {sw.Elapsed.TotalSeconds:F3}s.");
return(first);
}
_log?.Debug($"Collision when writing {rawEvents.Length} events after {sw.Elapsed.TotalSeconds:F3}s.");
return(null);
}
catch (Exception e)
{
_log?.Error($"When writing {rawEvents.Length} events after seq {_lastSequence}.", e);
throw;
}
}
/// <summary> Loop forever (or at least, until it's done). </summary>
/// <remarks> Any exceptions thrown are passed to the exception callback. </remarks>
private async Task Loop()
{
// Wait for initialization to finish and check success.
try
{
await Ready.ConfigureAwait(false);
}
catch (OperationCanceledException) { throw; }
catch (Exception e)
{
_log?.Error("While waiting to catch up with event stream.", e);
return;
}
// The auto-refresh process
// ========================
// This is a background task that checks periodically whether
// a synchronization with the remote stream has occurred. If
// it has not, it performs one.
#pragma warning disable CS4014
Task.Run(async() =>
{
while (!_cancel.IsCancellationRequested)
{
var syncStep = Wrapper.SyncStep;
// RefreshPeriod/2 because it's possible to have a
// syncStep increment happen right before this 'await',
// in which case the delay will execute twice before
// it detects that no sync is happening.
await Task.Delay(TimeSpan.FromSeconds(RefreshPeriod / 2), _cancel);
if (syncStep == Wrapper.SyncStep)
{
await CatchUpAsync(default(CancellationToken));
}
}
}, _cancel);
#pragma warning restore CS4014
// The actual loop
// ===============
while (!_cancel.IsCancellationRequested)
{
// This sleeps until an action becomes available in the queue
var nextAction = await _pending.Dequeue(_cancel).ConfigureAwait(false);
// The action does not throw (is it wrapped properly)
await nextAction().ConfigureAwait(false);
}
}
/// <summary> Append events, constructed from the state, to the stream. </summary>
/// <remarks>
/// Builder returns array of events to be appended, and additional data
/// that will be returned by this method. Builder may be called more than
/// once.
/// </remarks>
public async Task <AppendResult <T> > AppendEventsAsync <T>(
Func <TState, Append <TEvent, T> > builder,
CancellationToken cancel = default(CancellationToken))
{
var thrownByBuilder = false;
try
{
while (true)
{
thrownByBuilder = true;
var tuple = builder(Current);
thrownByBuilder = false;
// No events to append, just return result
if (tuple.Events == null || tuple.Events.Count == 0)
{
return(new AppendResult <T>(0, 0, tuple.Result));
}
// Append the events
var done = await Stream.WriteAsync(tuple.Events, cancel).ConfigureAwait(false);
if (done == null)
{
// Append failed. Catch up and try again.
await CatchUpAsync(cancel).ConfigureAwait(false);
}
else
{
// Append succeeded. Catch up with locally available events (including those
// that were just added), then return append information.
CatchUpLocal();
SyncStep++;
return(new AppendResult <T>(tuple.Events.Count, (uint)done, tuple.Result));
}
}
}
catch (OperationCanceledException)
{
throw;
}
catch (Exception e)
{
if (!thrownByBuilder)
{
_log.Error("While appending events", e);
}
throw;
}
}
public DalFileType GetById(long key)
{
if (key < 0)
{
var error = new ArgumentOutOfRangeException(nameof(key), "parametr can't be negative");
logger.Error(error, error.Message);
throw error;
}
return(context.Set <FileTypes>().FirstOrDefault(user => user.id == key).ToDalFileType());
}
public void SaveBooks(IEnumerable <Book> books)
{
if (ReferenceEquals(books, null))
{
throw new ArgumentNullException();
}
try
{
using (var fileStream = new FileStream(FilePath, FileMode.OpenOrCreate, FileAccess.Write))
{
new XmlSerializer(typeof(List <Book>)).Serialize(fileStream, new List <Book>(books));
}
logger.Trace($"Saved {books.Count()} books to {Environment.CurrentDirectory}'\'{FilePath}");
}
catch (IOException ex)
{
logger.Error($"error {ex.GetType()} in\n {ex.StackTrace}\n whith message {ex.Message}");
throw new Exception("Can't save data", ex);
}
}
public BookService(IEnumerable <Book> collection, IComparer <Book> comparer, ILogAdapter logger)
{
if (ReferenceEquals(collection, null))
{
logger.Error($"Faild to create new books storage -> collection is null\n {new StackTrace()}");
throw new ArgumentNullException();
}
if (ReferenceEquals(comparer, null))
{
comparer = Comparer <Book> .Default;
}
this.logger = logger;
booksStorage = new SortedSet <Book>(collection, comparer);
}
/// <summary> Initialize the wrapper and set <see cref="IsReady"/> to true. </summary>
/// <remarks>
/// Upon failure, logs the exception and tries again after a short delay, forever.
/// </remarks>
private async Task Initialize()
{
while (!_cancel.IsCancellationRequested)
{
try
{
await Wrapper.InitializeAsync(_cancel).ConfigureAwait(false);
_isReady = true;
return;
}
catch (OperationCanceledException) { throw; }
catch (Exception e)
{
_log.Error("Could not initialize EventStreamService", e);
_initFailure = e;
Wrapper.Reset();
}
await Task.Delay(TimeSpan.FromSeconds(5), _cancel).ConfigureAwait(false);
}
}
private static IEnumerable <IDataSource> GetDataSources()
{
var typeLocator = new TypeLocator();
IEnumerable <Type> types = typeLocator.GetAllMatchingTypes(IsValidDataSourceProvider);
foreach (Type filterType in types)
{
IDataSource filter;
try
{
filter = Activator.CreateInstance(filterType) as IDataSource;
}
catch (Exception e)
{
Logger.Error($"Unable to create {filterType.FullName} while GetDatasources. {e.Message}");
filter = null;
}
if (filter != null)
{
yield return(filter);
}
}
}
/// <summary>
/// Reifies a group of projections as a <typeparamref name="TState"/> object.
/// </summary>
public ReifiedProjectionGroup(IEnumerable <IProjection <TEvent> > projections, IProjectionCacheProvider cacheProvider = null, ILogAdapter log = null)
{
// Dirty reflection work to reify the individual projections and store their
// type parameter.
var reifiedByType = new Dictionary <Type, IReifiedProjection <TEvent> >();
foreach (var p in projections)
{
if (reifiedByType.ContainsKey(p.State))
{
log?.Error($"Found multiple projections for type {p.State}.");
throw new ArgumentException($"Multiple projections for type '{p.State}'", nameof(projections));
}
var reifiedProjectionType = typeof(ReifiedProjection <,>)
.MakeGenericType(typeof(TEvent), p.State);
var projectionType = typeof(IProjection <,>)
.MakeGenericType(typeof(TEvent), p.State);
var constructor = reifiedProjectionType
.GetTypeInfo()
.GetConstructor(new [] { projectionType, typeof(IProjectionCacheProvider), typeof(ILogAdapter) });
if (constructor == null)
{
throw new Exception("No constructor found for '" + reifiedProjectionType + "'");
}
IReifiedProjection <TEvent> reified;
try
{
reified = (IReifiedProjection <TEvent>)constructor.Invoke(new object[] { p, cacheProvider, log });
}
catch (TargetInvocationException e)
{
log?.Error($"When creating reified projection for type {p.State}.", e.InnerException);
throw e.InnerException;
}
reifiedByType.Add(p.State, reified);
}
// Easy case: a projection outputs the state type directly
IReifiedProjection <TEvent> direct;
if (reifiedByType.TryGetValue(typeof(TState), out direct))
{
_reifiedProjections = new[] { direct };
var directCast = (ReifiedProjection <TEvent, TState>)direct;
_refresh = () => directCast.Current;
InvalidateCurrent();
return;
}
// Hard case: state is made from the results of multiple independent
// projections. Need to write code to combine them.
var posByType = new Dictionary <Type, int>();
var reifiedByPos = new List <IReifiedProjection <TEvent> >();
var stateConstructor = typeof(TState)
.GetTypeInfo()
.GetConstructors()
.FirstOrDefault(c =>
{
var p = c.GetParameters();
if (p.Length == 0)
{
return(false);
}
return(p.All(info => reifiedByType.ContainsKey(info.ParameterType)));
});
if (stateConstructor == null)
{
throw new ArgumentException($"No compatible constructor found in '{typeof(TState)}'", nameof(projections));
}
// Build an expression that will extract the state components from "array" and
// pass them to the constructor.
var parameters = stateConstructor.GetParameters();
var array = Expression.Parameter(typeof(IReifiedProjection <TEvent>[]));
var arguments = new List <Expression>();
foreach (var p in parameters)
{
int pos;
if (!posByType.TryGetValue(p.ParameterType, out pos))
{
pos = posByType.Count;
posByType.Add(p.ParameterType, pos);
reifiedByPos.Add(reifiedByType[p.ParameterType]);
}
var argReified = Expression.Convert(
Expression.ArrayIndex(array, Expression.Constant(pos)),
typeof(ReifiedProjection <,>).MakeGenericType(typeof(TEvent), p.ParameterType));
arguments.Add(Expression.Property(argReified, "Current"));
}
var lambda = Expression.Lambda <Func <IReifiedProjection <TEvent>[], TState> >(
Expression.New(stateConstructor, arguments), array);
var extract = lambda.Compile();
var reifiedProjections = _reifiedProjections = reifiedByPos.ToArray();
_refresh = () => extract(reifiedProjections);
InvalidateCurrent();
}
public void Error(string message, Exception ex = null)
{
_log.Error(Elapsed + " " + message, ex);
}
/// <inheritdoc/> public static void Error(object caller, object message, params object[] replacements) => _log.Error(caller, message, replacements);