/// <summary>
/// Initializes a new instance of the
/// <see cref="DataLoader{TKey, TValue}"/> class.
/// </summary>
/// <param name="options">
/// An options object to configure the behavior of this particular
/// <see cref="DataLoader{TKey, TValue}"/>.
/// </param>
/// <param name="fetch">
/// A delegate to fetch data batches which will be invoked every time
/// when trying to setup a new batch request.
/// </param>
/// <exception cref="ArgumentNullException">
/// Throws if <paramref name="options"/> is <c>null</c>.
/// </exception>
/// <exception cref="ArgumentNullException">
/// Throws if <paramref name="fetch"/> is <c>null</c>.
/// </exception>
public DataLoader(
DataLoaderOptions <TKey> options,
FetchDataDelegate <TKey, TValue> fetch)
: base(options)
{
_fetch = fetch ?? throw new ArgumentNullException(nameof(fetch));
}
private static DataLoaderOptions CreateLocalOptions(DataLoaderOptions options)
{
DataLoaderOptions local = options.Copy();
local.MaxBatchSize = 1;
return(local);
}
public void RemoveEntry()
{
// arrange
FetchDataDelegate <string, string> fetch = async keys =>
await Task.FromResult(new IResult <string> [0])
.ConfigureAwait(false);
var options = new DataLoaderOptions <string>
{
Batching = false
};
var loader = new DataLoader <string, string>(options, fetch);
var key = "Foo";
loader.Set(key, Task.FromResult("Bar"));
// act
IDataLoader <string, string> result = loader.Remove(key);
// assert
Task <string> loadResult = loader.LoadAsync(key);
if (loadResult is IAsyncResult asyncResult)
{
asyncResult.AsyncWaitHandle.WaitOne();
}
Assert.Equal(loader, result);
Assert.NotNull(loadResult.Exception);
}
/// <summary>
/// Initializes a new instance of the
/// <see cref="DataLoaderBase{TKey, TValue}"/> class.
/// </summary>
/// <param name="options">
/// A configuration for <c>DataLoaders</c>.
/// </param>
/// <exception cref="ArgumentNullException">
/// Throws if <paramref name="options"/> is <c>null</c>.
/// </exception>
protected DataLoaderBase(DataLoaderOptions <TKey> options)
: this(options, new TaskCache <TValue>(
options?.CacheSize ?? Defaults.CacheSize,
options?.SlidingExpiration ??
Defaults.SlidingExpiration))
{
}
public async Task LoadCollectionResult()
{
// arrange
var expectedResult = Result <string> .Resolve("Bar");
FetchDataDelegate <string, string> fetch = async k =>
await Task.FromResult(new[] { expectedResult })
.ConfigureAwait(false);
var options = new DataLoaderOptions <string>
{
Batching = false
};
var loader = new DataLoader <string, string>(options, fetch);
var keys = new List <string> {
"Foo"
};
// act
IReadOnlyList <string> loadResult = await loader
.LoadAsync(keys)
.ConfigureAwait(false);
// assert
Assert.Collection(loadResult,
v => Assert.Equal(expectedResult.Value, v));
}
public async Task DispatchAsyncKeysValuesNotMatching()
{
// arrange
FetchDataDelegate <string, string> fetch = async keys =>
await Task.FromResult(new IResult <string> [0])
.ConfigureAwait(false);
var options = new DataLoaderOptions <string>
{
BatchRequestDelay = TimeSpan.FromMinutes(10)
};
var loader = new DataLoader <string, string>(options, fetch);
await Task.Delay(10);
Task <IReadOnlyList <string> > loadResult = loader.LoadAsync("Foo", "Bar");
await loader.DispatchAsync().ConfigureAwait(false);
// act
Func <Task> verify = () => loadResult;
// assert
await Assert.ThrowsAsync <InvalidOperationException>(verify)
.ConfigureAwait(false);
}
public void ConstructorAllProps()
{
// act
var options = new DataLoaderOptions <string>
{
AutoDispatching = false,
Batching = false,
BatchRequestDelay = TimeSpan.FromSeconds(1),
CacheKeyResolver = k => k,
CacheSize = 1,
Caching = false,
MaxBatchSize = 1,
SlidingExpiration = TimeSpan.FromSeconds(10)
};
// assert
Assert.False(options.AutoDispatching);
Assert.False(options.Batching);
Assert.Equal(TimeSpan.FromSeconds(1), options.BatchRequestDelay);
Assert.NotNull(options.CacheKeyResolver);
Assert.Equal(1, options.CacheSize);
Assert.False(options.Caching);
Assert.Equal(1, options.MaxBatchSize);
Assert.Equal(TimeSpan.FromSeconds(10), options.SlidingExpiration);
}
public async Task DispatchAsyncAuto()
{
// arrange
IResult <string> expectedResult = Result <string> .Resolve("Bar");
FetchDataDelegate <string, string> fetch = async keys =>
await Task.FromResult(new[] { expectedResult })
.ConfigureAwait(false);
var options = new DataLoaderOptions <string>
{
BatchRequestDelay = TimeSpan.FromMinutes(10)
};
var loader = new DataLoader <string, string>(options, fetch);
await Task.Delay(10);
Task <string> loadResult = loader.LoadAsync("Foo");
// act
await loader.DispatchAsync().ConfigureAwait(false);
// assert
Assert.Equal(expectedResult.Value,
await loadResult.ConfigureAwait(false));
}
public async Task DispatchAsyncNoBatching()
{
// arrange
IResult <string> expectedResult = Result <string> .Resolve("Bar");
FetchDataDelegate <string, string> fetch = async keys =>
await Task.FromResult(new[] { expectedResult })
.ConfigureAwait(false);
var options = new DataLoaderOptions <string>
{
Batching = false
};
var loader = new DataLoader <string, string>(options, fetch);
// this would block if batching would be enabled
var loadResult = await loader.LoadAsync("Foo")
.ConfigureAwait(false);
// act
await loader.DispatchAsync().ConfigureAwait(false);
// assert
Assert.Equal(expectedResult.Value, loadResult);
}
public async Task ClearAllEntries()
{
// arrange
FetchDataDelegate <string, string> fetch = async keys =>
await Task.FromResult(new IResult <string> [0])
.ConfigureAwait(false);
var options = new DataLoaderOptions <string>
{
Batching = false
};
var loader = new DataLoader <string, string>(options, fetch);
loader.Set("Foo", Task.FromResult("Bar"));
loader.Set("Bar", Task.FromResult("Baz"));
// act
IDataLoader <string, string> result = loader.Clear();
// assert
Func <Task> verify = () => loader.LoadAsync("Foo", "Bar");
Assert.Equal(loader, result);
await Assert.ThrowsAsync <InvalidOperationException>(verify)
.ConfigureAwait(false);
}
public void ConstructorEmpty()
{
// act
var options = new DataLoaderOptions <string>();
// assert
options.MatchSnapshot();
}
/// <summary>
/// Initializes a new instance of the <see cref="DataLoader{TKey, TValue}"/> class.
/// </summary>
/// <param name="batchScheduler">
/// A scheduler to tell the <c>DataLoader</c> when to dispatch buffered batches.
/// </param>
/// <param name="options">
/// An options object to configure the behavior of this particular
/// <see cref="DataLoader{TKey, TValue}"/>.
/// </param>
/// <exception cref="ArgumentNullException">
/// Throws if <paramref name="options"/> is <c>null</c>.
/// </exception>
protected DataLoaderBase(IBatchScheduler batchScheduler, DataLoaderOptions <TKey>?options)
{
_options = options ?? new DataLoaderOptions <TKey>();
_cache = _options.Cache ?? new TaskCache(_options.CacheSize);
_cacheKeyResolver = _options.CacheKeyResolver ?? ((TKey key) => key);
_batchScheduler = batchScheduler;
_maxBatchSize = _options.GetBatchSize();
}
public DataLoader(
IBatchScheduler batchScheduler,
FetchDataDelegate <TKey, TValue> fetch,
DataLoaderOptions <TKey>?options)
: base(batchScheduler, options)
{
_fetch = fetch ?? throw new ArgumentNullException(nameof(fetch));
}
public void ConstructorEmpty()
{
// act
var options = new DataLoaderOptions();
// assert
Assert.Null(options.Cache);
Assert.True(options.Caching);
Assert.Equal(1024, options.MaxBatchSize);
Assert.Null(options.DiagnosticEvents);
}
/// <summary>
/// Initializes a new instance of the
/// <see cref="DataLoaderBase{TKey, TValue}"/> class.
/// </summary>
/// <param name="options">
/// A configuration for <c>DataLoaders</c>.
/// </param>
/// <param name="cache">
/// A cache instance for <c>Tasks</c>.
/// </param>
/// <exception cref="ArgumentNullException">
/// Throws if <paramref name="options"/> is <c>null</c>.
/// </exception>
/// <exception cref="ArgumentNullException">
/// Throws if <paramref name="cache"/> is <c>null</c>.
/// </exception>
protected DataLoaderBase(DataLoaderOptions <TKey> options, ITaskCache <TValue> cache)
{
_options = options ??
throw new ArgumentNullException(nameof(options));
_buffer = new TaskCompletionBuffer <TKey, TValue>();
_cache = cache ?? throw new ArgumentNullException(nameof(cache));
_cacheKeyResolver = _options.CacheKeyResolver ??
((TKey key) => key);
StartAsyncBackgroundDispatching();
}
public void ConstructorBFetchNull()
{
// arrange
FetchDataDelegate <string, string> fetch = null;
var options = new DataLoaderOptions <string>();
// act
Action verify = () => new DataLoader <string, string>(options,
fetch);
// assert
Assert.Throws <ArgumentNullException>("fetch", verify);
}
public void DispatchAsyncNoException()
{
// arrange
FetchDataDelegate <string, string> fetch = TestHelpers
.CreateFetch <string, string>();
var options = new DataLoaderOptions <string>();
var loader = new DataLoader <string, string>(options, fetch);
// act
Action verify = () => loader.DispatchAsync();
// assert
Assert.Null(Record.Exception(verify));
}
public void LoadCollectionNoException()
{
// arrange
FetchDataDelegate <string, string> fetch = TestHelpers
.CreateFetch <string, string>("Bar");
var options = new DataLoaderOptions <string>();
var loader = new DataLoader <string, string>(options, fetch);
// act
Action verify = () => loader.LoadAsync(new List <string>());
// assert
Assert.Null(Record.Exception(verify));
}
public void SetNoException()
{
// arrange
FetchDataDelegate <string, string> fetch = TestHelpers
.CreateFetch <string, string>();
var options = new DataLoaderOptions <string>();
var loader = new DataLoader <string, string>(options, fetch);
var key = "Foo";
string value = null;
// act
Action verify = () => loader.Set(key, value);
// assert
Assert.Null(Record.Exception(verify));
}
public void SetKeyNull()
{
// arrange
FetchDataDelegate <string, string> fetch = TestHelpers
.CreateFetch <string, string>();
var options = new DataLoaderOptions <string>();
var loader = new DataLoader <string, string>(options, fetch);
string key = null;
var value = "Bar";
// act
Action verify = () => loader.Set(key, value);
// assert
Assert.Throws <ArgumentNullException>("key", verify);
}
public void ConstructorBOptionsNull()
{
// arrange
FetchDataDelegate <string, string> fetch = async keys =>
await Task.FromResult(new IResult <string> [0])
.ConfigureAwait(false);
DataLoaderOptions <string> options = null;
// act
Action verify = () => new DataLoader <string, string>(options,
fetch);
// assert
Assert.Throws <ArgumentNullException>("options", verify);
}
public void ClearNoException()
{
// arrange
FetchDataDelegate <string, string> fetch = async keys =>
await Task.FromResult(new IResult <string> [0])
.ConfigureAwait(false);
var options = new DataLoaderOptions <string>();
var loader = new DataLoader <string, string>(options, fetch);
// act
Action verify = () => loader.Clear();
// assert
Assert.Null(Record.Exception(verify));
}
public void ConstructorEmpty()
{
// act
var options = new DataLoaderOptions <string>();
// assert
Assert.False(options.AutoDispatching);
Assert.True(options.Batching);
Assert.Equal(TimeSpan.FromMilliseconds(50),
options.BatchRequestDelay);
Assert.Null(options.CacheKeyResolver);
Assert.Equal(1000, options.CacheSize);
Assert.True(options.Caching);
Assert.Equal(0, options.MaxBatchSize);
Assert.Equal(TimeSpan.Zero, options.SlidingExpiration);
}
public async Task ExecuteBatchRequest()
{
var listener = new DispatchingListener();
var observer = new DispatchingObserver(listener);
using (DiagnosticListener.AllListeners.Subscribe(observer))
{
// arrange
FetchDataDelegate <string, string> fetch = async keys =>
{
var error = new Exception("Quux");
return(await Task.FromResult(new[]
{
Result <string> .Reject(error)
}).ConfigureAwait(false));
};
var options = new DataLoaderOptions <string>();
var loader = new DataLoader <string, string>(options, fetch);
// act
try
{
await loader.LoadAsync("Foo").ConfigureAwait(false);
}
catch
{
}
// assert
Assert.Collection(listener.Keys,
(key) => Assert.Equal("Foo", key));
Assert.Collection(listener.Values,
(item) =>
{
Assert.Equal("Foo", item.Key);
Assert.True(item.Value.IsError);
Assert.Equal("Quux", item.Value.Error.Message);
});
Assert.Collection(listener.Errors,
(item) =>
{
Assert.Equal("Foo", item.Key);
Assert.Equal("Quux", item.Value.Message);
});
}
}
public void IDataLoaderLoadSingleNoException()
{
// arrange
FetchDataDelegate <string, string> fetch = TestHelpers
.CreateFetch <string, string>("Bar");
var options = new DataLoaderOptions <string>();
IDataLoader loader = new DataLoader <string, string>(
options,
fetch);
var key = "Foo";
// act
Action verify = () => loader.LoadAsync(key);
// assert
Assert.Null(Record.Exception(verify));
}
public async Task DispatchAsyncNoException()
{
// arrange
FetchDataDelegate <string, string> fetch = async keys =>
await Task.FromResult(new IResult <string> [0])
.ConfigureAwait(false);
var options = new DataLoaderOptions <string>();
var loader = new DataLoader <string, string>(options, fetch);
// act
Func <Task> verify = () => loader.DispatchAsync();
// assert
Assert.Null(await Record.ExceptionAsync(verify)
.ConfigureAwait(false));
}
public void ConstructorAllProps1()
{
// act
var options = new DataLoaderOptions
{
Cache = new TaskCache(1),
Caching = true,
MaxBatchSize = 1,
DiagnosticEvents = new DataLoaderDiagnosticEventListener()
};
// assert
Assert.NotNull(options.Cache);
Assert.True(options.Caching);
Assert.Equal(1, options.MaxBatchSize);
Assert.NotNull(options.DiagnosticEvents);
}
public void ConstructorAllProps2()
{
// act
var options = new DataLoaderOptions
{
Cache = null,
Caching = false,
MaxBatchSize = 10,
DiagnosticEvents = null
};
// assert
Assert.Null(options.Cache);
Assert.False(options.Caching);
Assert.Equal(10, options.MaxBatchSize);
Assert.Null(options.DiagnosticEvents);
}
public async Task SetNewCacheEntry()
{
// arrange
FetchDataDelegate <string, string> fetch = TestHelpers
.CreateFetch <string, string>();
var options = new DataLoaderOptions <string>();
var loader = new DataLoader <string, string>(options, fetch);
var key = "Foo";
var value = "Bar";
// act
loader.Set(key, value);
// assert
var loadResult = await loader.LoadAsync(key).ConfigureAwait(false);
Assert.Equal(value, loadResult);
}
public void ConstructorAllProps()
{
// act
var options = new DataLoaderOptions <string>
{
Batch = false,
Cache = new TaskCache(1),
CacheKeyResolver = k => k,
CacheSize = 1,
Caching = false,
MaxBatchSize = 1
};
// assert
options.MatchSnapshot(matchOptions => matchOptions
.Assert(fieldOption =>
Assert.NotNull(fieldOption.Field <object>("CacheKeyResolver"))));
}
