Add TCP Healthcheck

pkg/config/dynamic/tcp_config.go

@@ -39,7 +39,8 @@ type TCPService struct {
 
 // TCPWeightedRoundRobin is a weighted round robin tcp load-balancer of services.
 type TCPWeightedRoundRobin struct {
-	Services []TCPWRRService `json:"services,omitempty" toml:"services,omitempty" yaml:"services,omitempty" export:"true"`
+	Services    []TCPWRRService `json:"services,omitempty" toml:"services,omitempty" yaml:"services,omitempty" export:"true"`
+	HealthCheck *HealthCheck    `json:"healthCheck,omitempty" toml:"healthCheck,omitempty" yaml:"healthCheck,omitempty" label:"allowEmpty" file:"allowEmpty" kv:"allowEmpty" export:"true"`
 }
 
 // +k8s:deepcopy-gen=true
@@ -86,7 +87,6 @@ type RouterTCPTLSConfig struct {
 type TCPServersLoadBalancer struct {
 	Servers          []TCPServer `json:"servers,omitempty" toml:"servers,omitempty" yaml:"servers,omitempty" label-slice-as-struct:"server" export:"true"`
 	ServersTransport string      `json:"serversTransport,omitempty" toml:"serversTransport,omitempty" yaml:"serversTransport,omitempty" export:"true"`
-
 	// ProxyProtocol holds the PROXY Protocol configuration.
 	// Deprecated: use ServersTransport to configure ProxyProtocol instead.
 	ProxyProtocol *ProxyProtocol `json:"proxyProtocol,omitempty" toml:"proxyProtocol,omitempty" yaml:"proxyProtocol,omitempty" label:"allowEmpty" file:"allowEmpty" kv:"allowEmpty" export:"true"`
@@ -96,7 +96,8 @@ type TCPServersLoadBalancer struct {
 	// connection. It is a duration in milliseconds, defaulting to 100. A negative value
 	// means an infinite deadline (i.e. the reading capability is never closed).
 	// Deprecated: use ServersTransport to configure the TerminationDelay instead.
-	TerminationDelay *int `json:"terminationDelay,omitempty" toml:"terminationDelay,omitempty" yaml:"terminationDelay,omitempty" export:"true"`
+	TerminationDelay *int                  `json:"terminationDelay,omitempty" toml:"terminationDelay,omitempty" yaml:"terminationDelay,omitempty" export:"true"`
+	HealthCheck      *TCPServerHealthCheck `json:"healthCheck,omitempty" toml:"healthCheck,omitempty" yaml:"healthCheck,omitempty" label:"allowEmpty" file:"allowEmpty" kv:"allowEmpty" export:"true"`
 }
 
 // Mergeable tells if the given service is mergeable.
@@ -176,3 +177,21 @@ type TLSClientConfig struct {
 	PeerCertURI        string                  `description:"Defines the URI used to match against SAN URI during the peer certificate verification." json:"peerCertURI,omitempty" toml:"peerCertURI,omitempty" yaml:"peerCertURI,omitempty" export:"true"`
 	Spiffe             *Spiffe                 `description:"Defines the SPIFFE TLS configuration." json:"spiffe,omitempty" toml:"spiffe,omitempty" yaml:"spiffe,omitempty" label:"allowEmpty" file:"allowEmpty" export:"true"`
 }
+
+// +k8s:deepcopy-gen=true
+
+// TCPServerHealthCheck holds the HealthCheck configuration.
+type TCPServerHealthCheck struct {
+	Port              int              `json:"port,omitempty" toml:"port,omitempty,omitzero" yaml:"port,omitempty" export:"true"`
+	Send              string           `json:"send,omitempty" toml:"send,omitempty" yaml:"send,omitempty" export:"true"`
+	Expect            string           `json:"expect,omitempty" toml:"expect,omitempty" yaml:"expect,omitempty" export:"true"`
+	Interval          ptypes.Duration  `json:"interval,omitempty" toml:"interval,omitempty" yaml:"interval,omitempty" export:"true"`
+	UnhealthyInterval *ptypes.Duration `json:"unhealthyInterval,omitempty" toml:"unhealthyInterval,omitempty" yaml:"unhealthyInterval,omitempty" export:"true"`
+	Timeout           ptypes.Duration  `json:"timeout,omitempty" toml:"timeout,omitempty" yaml:"timeout,omitempty" export:"true"`
+}
+
+// SetDefaults sets the default values for a TCPServerHealthCheck.
+func (t *TCPServerHealthCheck) SetDefaults() {
+	t.Interval = DefaultHealthCheckInterval
+	t.Timeout = DefaultHealthCheckTimeout
+}

pkg/config/dynamic/zz_generated.deepcopy.go

@@ -2001,6 +2001,27 @@ func (in *TCPServer) DeepCopy() *TCPServer {
 	return out
 }
 
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *TCPServerHealthCheck) DeepCopyInto(out *TCPServerHealthCheck) {
+	*out = *in
+	if in.UnhealthyInterval != nil {
+		in, out := &in.UnhealthyInterval, &out.UnhealthyInterval
+		*out = new(paersertypes.Duration)
+		**out = **in
+	}
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new TCPServerHealthCheck.
+func (in *TCPServerHealthCheck) DeepCopy() *TCPServerHealthCheck {
+	if in == nil {
+		return nil
+	}
+	out := new(TCPServerHealthCheck)
+	in.DeepCopyInto(out)
+	return out
+}
+
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *TCPServersLoadBalancer) DeepCopyInto(out *TCPServersLoadBalancer) {
 	*out = *in
@@ -2019,6 +2040,11 @@ func (in *TCPServersLoadBalancer) DeepCopyInto(out *TCPServersLoadBalancer) {
 		*out = new(int)
 		**out = **in
 	}
+	if in.HealthCheck != nil {
+		in, out := &in.HealthCheck, &out.HealthCheck
+		*out = new(TCPServerHealthCheck)
+		(*in).DeepCopyInto(*out)
+	}
 	return
 }
 
@@ -2115,6 +2141,11 @@ func (in *TCPWeightedRoundRobin) DeepCopyInto(out *TCPWeightedRoundRobin) {
 			(*in)[i].DeepCopyInto(&(*out)[i])
 		}
 	}
+	if in.HealthCheck != nil {
+		in, out := &in.HealthCheck, &out.HealthCheck
+		*out = new(HealthCheck)
+		**out = **in
+	}
 	return
 }
 

pkg/config/runtime/runtime_tcp.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"slices"
+	"sync"
 
 	"github.com/rs/zerolog/log"
 	"github.com/traefik/traefik/v3/pkg/config/dynamic"
@@ -87,6 +88,9 @@ type TCPServiceInfo struct {
 	// It is the caller's responsibility to set the initial status.
 	Status string   `json:"status,omitempty"`
 	UsedBy []string `json:"usedBy,omitempty"` // list of routers using that service
+
+	serverStatusMu sync.RWMutex
+	serverStatus   map[string]string // keyed by server address
 }
 
 // AddError adds err to s.Err, if it does not already exist.
@@ -110,6 +114,33 @@ func (s *TCPServiceInfo) AddError(err error, critical bool) {
 	}
 }
 
+// UpdateServerStatus sets the status of the server in the TCPServiceInfo.
+func (s *TCPServiceInfo) UpdateServerStatus(server, status string) {
+	s.serverStatusMu.Lock()
+	defer s.serverStatusMu.Unlock()
+
+	if s.serverStatus == nil {
+		s.serverStatus = make(map[string]string)
+	}
+	s.serverStatus[server] = status
+}
+
+// GetAllStatus returns all the statuses of all the servers in TCPServiceInfo.
+func (s *TCPServiceInfo) GetAllStatus() map[string]string {
+	s.serverStatusMu.RLock()
+	defer s.serverStatusMu.RUnlock()
+
+	if len(s.serverStatus) == 0 {
+		return nil
+	}
+
+	allStatus := make(map[string]string, len(s.serverStatus))
+	for k, v := range s.serverStatus {
+		allStatus[k] = v
+	}
+	return allStatus
+}
+
 // TCPMiddlewareInfo holds information about a currently running middleware.
 type TCPMiddlewareInfo struct {
 	*dynamic.TCPMiddleware // dynamic configuration