Randomize feature of StaticConnectionPool does nothing

[kit299]

NEST/Elasticsearch.Net version: 6.0.2 and 7.2.1 (presumably others)

Elasticsearch version: irrelevant, but 6.6.1

Description of the problem including expected versus actual behavior:

See: https://github.com/elastic/elasticsearch-net/blob/master/src/Elasticsearch.Net/ConnectionPool/StaticConnectionPool.cs
(current latest revision is c330114)

In theory passing 'true' for the randomize parameter (true is also the default for this parameter) will cause the order of the supplied nodes to be randomized.
This should happen in the function SortNodes() which (if no node scorer is available) will check the Randomize property and, if true, will use OrderBy(Random.Next()) to return the nodes in a random order.

In practice, because of the way the constructors are nested, SortNodes is called from the protected constructor BEFORE the Randomize property is initialized by the public constructor - so when read in SortNodes the Randomize property has not yet been initialized and will always have its default value of false.

Steps to reproduce:

var uris = new[]
{
	new Uri("https://10.0.0.1:9200/"),
	new Uri("https://10.0.0.2:9200/"),
	new Uri("https://10.0.0.3:9200/")
};

var pool = new StaticConnectionPool(uris);
var nodeView = pool.CreateView();

Debug.Assert(nodeView.First().Uri.ToString() == "https://10.0.0.1:9200/");

Expected: The assertion should fail most of the time.
Actual: The assertion never fails.

[russcam]

Thanks for opening @kit299, this is a bug. Will need to look into the cleanest way to implement this in 7.x and 6.x.

[russcam]

I've opened #4112 to address