public async Task InvokeAsync(HttpContext context, IanvsContext ianvsContext,
IIanvsConfigurationStore ianvsConfiguration, LoadBalancerFactory loadBalancerFactory)
{
// TODO: Implement Load Balancing
// WIP - https://github.com/onyx-ws/ianvs/issues/5
// Support for different load balancing modes - Random/Round Robin/etc.
_logger.LogInformation($"{Environment.MachineName} {ianvsContext.RequestId} finding load balancer");
string loadBalancerMode = ianvsContext.MatchedOperation.LoadBalancerMethod;
if (string.IsNullOrWhiteSpace(loadBalancerMode))
{
loadBalancerMode = ianvsContext.MatchedEndpoint.LoadBalancerMethod;
}
if (string.IsNullOrWhiteSpace(loadBalancerMode))
{
loadBalancerMode = ianvsConfiguration.LoadBalancerMethod;
}
ILoadBalancer loadBalancer = loadBalancerFactory.GetLoadBalancer(loadBalancerMode);
_logger.LogInformation($"{Environment.MachineName} {ianvsContext.RequestId} {loadBalancerMode} load balancer found");
// Operation level servers take priority
if (!(ianvsContext.MatchedOperation.Servers?.Count == 0))
{
_logger.LogInformation($"{Environment.MachineName} {ianvsContext.RequestId} Selecting server out of {ianvsContext.MatchedOperation.Servers.Count} server(s)");
ianvsContext.TargetServer = await loadBalancer.Next(ianvsContext.MatchedOperation.Servers);
_logger.LogInformation($"{Environment.MachineName} {ianvsContext.RequestId} Server {ianvsContext.TargetServer.Url} selected");
}
// If not operation level servers then use Endpoint level servers
else if (!(ianvsContext.MatchedEndpoint.Servers?.Count == 0))
{
_logger.LogInformation($"{Environment.MachineName} {ianvsContext.RequestId} Selecting server out of {ianvsContext.MatchedEndpoint.Servers.Count} server(s)");
ianvsContext.TargetServer = await loadBalancer.Next(ianvsContext.MatchedEndpoint.Servers);
_logger.LogInformation($"{Environment.MachineName} {ianvsContext.RequestId} Server {ianvsContext.TargetServer.Url} selected");
}
// Else use global servers defined
else
{
_logger.LogInformation($"{Environment.MachineName} {ianvsContext.RequestId} Selecting server out of {ianvsConfiguration.Servers.Count} server(s)");
ianvsContext.TargetServer = await loadBalancer.Next(ianvsConfiguration.Servers);
_logger.LogInformation($"{Environment.MachineName} {ianvsContext.RequestId} Server {ianvsContext.TargetServer.Url} selected");
}
ianvsContext.TargetUrl = ianvsContext.TargetServer.Url + (ianvsContext.MatchedEndpoint.Url == "/" ? "" : ianvsContext.MatchedEndpoint.Url);
await _next(context);
}
private Uri GetRedirectUri(HttpListenerRequest request)
{
var redirectUriBuilder = new UriBuilder(request.Url);
var redirectUri = loadBalancer.Next();
if (redirectUri == null)
{
return(null);
}
redirectUriBuilder.Port = redirectUri.Port;
redirectUriBuilder.Host = redirectUri.Host;
return(redirectUriBuilder.Uri);
}
public Connection GetRandomConnection()
{
if (IsSmartRoutingEnabled)
{
var member = _loadBalancer.Next();
if (member != null)
{
var connection = GetConnection(member.Uuid);
if (connection != null)
{
return(connection);
}
}
}
return(_connections.Values.SingleOrDefault());
}
public virtual Address Next()
{
IMember member = _loadBalancer.Next();
return(member == null ? null : member.GetAddress());
}
