public async override Task <object> Execute(BalancerData balancerData, HttpContext context, RawHandler handler)
{
var vhost = context.Items["bal-vhost"] as BalancerOption;
var key = balancerData.Scores.OrderByDescending(x => x.Value).FirstOrDefault().Key;
var node = vhost.Nodes[key];
await handler.HandleRequest(context, node);
return(node);
}
public async override Task <object> Execute(BalancerData balancerData, HttpContext context, RawHandler handler)
{
var vhost = context.Items["bal-vhost"] as BalancerOption;
balancerData.LastServed = (balancerData.LastServed + 1) % vhost.Nodes.Length;
var node = vhost.Nodes[balancerData.LastServed];
await handler.HandleRequest(context, node);
return(node);
}
public override async Task InvokeAsync(HttpContext context)
{
logger.LogDebug("Invoke BalancerMiddleware start");
var host = context.Request.Host.Value;
var scheme = context.Request.Scheme;
var port = context.Request.Host.Port;
var path = context.Request.Path;
var vhosts = pluginConfig?.Balancer?.Where(x => x.Host.Equals(host, StringComparison.InvariantCultureIgnoreCase) &&
x.Scheme.Equals(scheme, StringComparison.InvariantCultureIgnoreCase) &&
new Regex(x.Path).Match(path).Success&&
x.Port == port && x.Enable).ToList();
// TODO: get regex that not contains other regex
var vhost = vhosts?.OrderByDescending(x => x.Path?.Length).FirstOrDefault();
if (vhost != null)
{
vhost.Nodes = vhost.Nodes.Where(x => x.Enable).ToArray();
}
context.Items["bal-host"] = host;
context.Items["bal-vhost"] = vhost;
var policy = dispatcher.GetActiveBalancerPolicy(context);
if (policy != null)
{
BalancerData balancerData = null;
if (!data.ContainsKey(host))
{
balancerData = data[host] = new BalancerData();
for (int i = 0; i < vhost.Nodes.Length; i++)
{
balancerData.Scores[i] = 0;
}
}
else
{
balancerData = data[host];
}
context.Request.Headers["X-Forwarded-For"] = context.Connection.RemoteIpAddress.ToString();
context.Request.Headers["X-Forwarded-Proto"] = context.Request.Protocol.ToString();
int portDest = context.Request.Host.Port ?? (context.Request.IsHttps ? 443 : 80);
context.Request.Headers["X-Forwarded-Port"] = portDest.ToString();
var handlerType = context.WebSockets.IsWebSocketRequest ? HandlerProtocolType.Socket : HandlerProtocolType.Http;
context.Items["bal-destination"] = await policy.Execute(balancerData, context, handlers.First(x => x.HandlerRequestType == handlerType));
}
else
{
await next(context);
}
}
/// <summary>
/// Request count implementation
/// </summary>
/// <param name="balancerData"></param>
/// <param name="options"></param>
/// <returns></returns>
private Node RequestCount(BalancerData balancerData, BalancerOptions options)
{
var key = balancerData.Scores.OrderByDescending(x => x.Value).FirstOrDefault().Key;
return(options.Nodes[key]);
if (balancerData.Scores[key] + 1 < long.MaxValue)
{
balancerData.Scores[key]++;
}
else
{
//If i'm going outside long range I need a reset.
//i'm the lower value, so if I'm not able to increments all other have my same value (if not, they had ben triggered this previously)
for (int i = 0; i < balancerData.Scores.Count; i++)
{
balancerData.Scores[i] = 0;
}
}
}
public async override Task InvokeImpl(HttpContext context, string host, VHostOptions vhost, IConfigurationSection settings)
{
BalancerOptions options = new BalancerOptions();
settings.Bind("Settings:Balancer", options);
BalancerData balancerData = null;
if (!data.ContainsKey(host))
{
balancerData = data[host] = new BalancerData();
for (int i = 0; i < options.Nodes.Length; i++)
{
balancerData.Scores[i] = 0;
}
}
else
{
balancerData = data[host];
}
//Different logic basing on algoritm
//TODO: make it generic using interface\implementation for algoritm
if (options.Policy == "RoundRobin")
{
context.Items["bal-destination"] = RoundRobin(balancerData, options);
}
else if (options.Policy == "RequestCount")
{
context.Items["bal-destination"] = RequestCount(balancerData, options);
}
//Alter request
context.Request.Headers["X-Forwarded-For"] = context.Connection.RemoteIpAddress.ToString();
context.Request.Headers["X-Forwarded-Proto"] = context.Request.Protocol.ToString();
int port = context.Request.Host.Port ?? (context.Request.IsHttps ? 443 : 80);
context.Request.Headers["X-Forwarded-Port"] = port.ToString();
}
public abstract Task <object> Execute(BalancerData balancerData, HttpContext context, RawHandler handler);
/// <summary>
/// Roud robin implementation
/// </summary>
/// <param name="balancerData"></param>
/// <param name="options"></param>
/// <returns></returns>
private object RoundRobin(BalancerData balancerData, BalancerOptions options)
{
balancerData.LastServed = (balancerData.LastServed + 1) % options.Nodes.Length;
return(options.Nodes[balancerData.LastServed]);
}
