public void EachViewStartsAtNextPositionAndWrapsOver()
{
var uris = Enumerable.Range(9200, NumberOfNodes).Select(p => new Uri("http://localhost:" + p));
var staticPool = new StickyConnectionPool(uris);
this.AssertCreateView(staticPool);
}
public void EachViewDoesNotSkip()
{
var seeds = Enumerable.Range(9200, NumberOfNodes).Select(p => new Node(new Uri("http://localhost:" + p))).ToList();
var pool = new StickyConnectionPool(seeds);
for (var i = 0; i < 20; i++)
{
var node = pool.CreateView().First();
node.Uri.Port.Should().Be(9200);
node = pool.CreateView().First();
node.Uri.Port.Should().Be(9200);
node = pool.CreateView().First();
node.Uri.Port.Should().Be(9200);
}
}
public void AssertCreateView(StickyConnectionPool pool)
{
/**
* Here we have setup a static connection pool seeded with 10 nodes.
* So what order we expect? Imagine the following:
*
* Thread A calls GetNext and gets returned the first live node
* Thread B calls GetNext() and gets returned the same node as it's still the first live.
*/
var startingPositions = Enumerable.Range(0, NumberOfNodes)
.Select(i => pool.CreateView().First())
.Select(n => n.Uri.Port)
.ToList();
var expectedOrder = Enumerable.Repeat(9200, NumberOfNodes);
startingPositions.Should().ContainInOrder(expectedOrder);
}
public void EachViewStartsAtNextPositionAndWrapsOver()
{
var numberOfNodes = 10;
var uris = Enumerable.Range(9200, numberOfNodes).Select(p => new Uri("http://localhost:" + p));
var pool = new StickyConnectionPool(uris);
/**
* Here we have setup a sticky connection pool seeded with 10 nodes.
* So what order we expect? Imagine the following:
*
* Thread A calls GetNext and gets returned the first live node
* Thread B calls GetNext() and gets returned the same node as it's still the first live.
*/
var startingPositions = Enumerable.Range(0, numberOfNodes)
.Select(i => pool.CreateView().First())
.Select(n => n.Uri.Port)
.ToList();
var expectedOrder = Enumerable.Repeat(9200, numberOfNodes);
startingPositions.Should().ContainInOrder(expectedOrder);
}
public void ViewSeesResurrectedNodes()
{
var dateTimeProvider = new TestableDateTimeProvider();
var seeds = Enumerable.Range(9200, NumberOfNodes).Select(p => new Node(new Uri("http://localhost:" + p))).ToList();
seeds.First().MarkDead(dateTimeProvider.Now().AddDays(1));
var pool = new StickyConnectionPool(seeds, dateTimeProvider: dateTimeProvider);
for (var i = 0; i < 20; i++)
{
var node = pool.CreateView().First();
node.Uri.Port.Should().Be(9201);
node = pool.CreateView().First();
node.Uri.Port.Should().Be(9201);
}
/** If we forward our clock 2 days the node that was marked dead until tomorrow (or yesterday!) should be resurrected */
dateTimeProvider.ChangeTime(d => d.AddDays(2));
var n = pool.CreateView().First();
n.Uri.Port.Should().Be(9200);
n = pool.CreateView().First();
n.Uri.Port.Should().Be(9200);
n = pool.CreateView().First();
n.Uri.Port.Should().Be(9200);
n.IsResurrected.Should().BeTrue();
}
public void EachViewSeesNextButSkipsTheDeadNode()
{
var seeds = Enumerable.Range(9200, NumberOfNodes).Select(p => new Node(new Uri("http://localhost:" + p))).ToList();
seeds.First().MarkDead(DateTime.Now.AddDays(1));
var pool = new StickyConnectionPool(seeds);
for (var i = 0; i < 20; i++)
{
var node = pool.CreateView().First();
node.Uri.Port.Should().Be(9201);
node = pool.CreateView().First();
node.Uri.Port.Should().Be(9201);
}
/** After we mark the first node alive again we expect it to be hit again*/
seeds.First().MarkAlive();
for (var i = 0; i < 20; i++)
{
var node = pool.CreateView().First();
node.Uri.Port.Should().Be(9200);
node = pool.CreateView().First();
node.Uri.Port.Should().Be(9200);
node = pool.CreateView().First();
node.Uri.Port.Should().Be(9200);
}
}
/**[[sticky-connection-pool]]
* === StickyConnectionPool
* A type of `IConnectionPool` that returns the first live node such that it is sticky between
* requests.
* It uses https://msdn.microsoft.com/en-us/library/system.threading.interlocked(v=vs.110).aspx[`System.Threading.Interlocked`]
* to keep an _indexer_ to the last live node in a thread safe manner.
*/
[U] public void Sticky()
{
var uris = Enumerable.Range(9200, 5).Select(p => new Uri("http://localhost:" + p));
/** a connection pool can be seeded using an enumerable of `Uri` */
var pool = new StickyConnectionPool(uris);
/** Or using an enumerable of `Node`.
* A major benefit here is you can include known node roles when seeding and
* NEST can use this information to favour sniffing on master eligible nodes first
* and take master only nodes out of rotation for issuing client calls on.
*/
var nodes = uris.Select(u=>new Node(u));
pool = new StickyConnectionPool(nodes);
/** This type of pool is hardwired to opt out of reseeding (and hence sniffing)*/
pool.SupportsReseeding.Should().BeFalse();
/** but does support pinging */
pool.SupportsPinging.Should().BeTrue();
/** To create a client using the sticky connection pool pass
* the connection pool to the `ConnectionSettings` you pass to `ElasticClient`
*/
var client = new ElasticClient(new ConnectionSettings(pool));
client.ConnectionSettings.ConnectionPool.Should().BeOfType<StickyConnectionPool>();
}
