package agent import ( "fmt" "time" "github.com/hashicorp/consul/agent/structs" ) func (a *Agent) sidecarServiceID(serviceID string) string { return serviceID + "-sidecar-proxy" } // sidecarServiceFromNodeService returns a *structs.NodeService representing a // sidecar service with all defaults populated based on the current agent // config. // // It assumes the ns has been validated already which means the nested // SidecarService is also already validated.It also assumes that any check // definitions within the sidecar service definition have been validated if // necessary. If no sidecar service is defined in ns, then nil is returned with // nil error. // // The second return argument is a list of CheckTypes to register along with the // service. // // The third return argument is the effective Token to use for the sidecar // registration. This will be the same as the token parameter passed unless the // SidecarService definition contains a distinct one. func (a *Agent) sidecarServiceFromNodeService(ns *structs.NodeService, token string) (*structs.NodeService, []*structs.CheckType, string, error) { if ns.Connect.SidecarService == nil { return nil, nil, "", nil } // Start with normal conversion from service definition sidecar := ns.Connect.SidecarService.NodeService() // Override the ID which must always be consistent for a given outer service // ID. We rely on this for lifecycle management of the nested definition. sidecar.ID = a.sidecarServiceID(ns.ID) // Set some meta we can use to disambiguate between service instances we added // later and are responsible for deregistering. if sidecar.Meta != nil { // Meta is non-nil validate it before we add the special key so we can // enforce that user cannot add a consul- prefix one. if err := structs.ValidateMetadata(sidecar.Meta, false); err != nil { return nil, nil, "", err } } // Copy the service metadata from the original service if no other meta was provided if len(sidecar.Meta) == 0 && len(ns.Meta) > 0 { if sidecar.Meta == nil { sidecar.Meta = make(map[string]string) } for k, v := range ns.Meta { sidecar.Meta[k] = v } } // Copy the tags from the original service if no other tags were specified if len(sidecar.Tags) == 0 && len(ns.Tags) > 0 { sidecar.Tags = append(sidecar.Tags, ns.Tags...) } // Flag this as a sidecar - this is not persisted in catalog but only needed // in local agent state to disambiguate lineage when deregistering the parent // service later. sidecar.LocallyRegisteredAsSidecar = true // See if there is a more specific token for the sidecar registration if ns.Connect.SidecarService.Token != "" { token = ns.Connect.SidecarService.Token } // Setup some sane connect proxy defaults. if sidecar.Kind == "" { sidecar.Kind = structs.ServiceKindConnectProxy } if sidecar.Service == "" { sidecar.Service = ns.Service + "-sidecar-proxy" } if sidecar.Address == "" { // Inherit address from the service if it's provided sidecar.Address = ns.Address } // Proxy defaults if sidecar.Proxy.DestinationServiceName == "" { sidecar.Proxy.DestinationServiceName = ns.Service } if sidecar.Proxy.DestinationServiceID == "" { sidecar.Proxy.DestinationServiceID = ns.ID } if sidecar.Proxy.LocalServiceAddress == "" { sidecar.Proxy.LocalServiceAddress = "127.0.0.1" } if sidecar.Proxy.LocalServicePort < 1 { sidecar.Proxy.LocalServicePort = ns.Port } // Allocate port if needed (min and max inclusive). rangeLen := a.config.ConnectSidecarMaxPort - a.config.ConnectSidecarMinPort + 1 if sidecar.Port < 1 && a.config.ConnectSidecarMinPort > 0 && rangeLen > 0 { // This did pick at random which was simpler but consul reload would assign // new ports to all the sidecars since it unloads all state and // re-populates. It also made this more difficult to test (have to pin the // range to one etc.). Instead we assign sequentially, but rather than N^2 // lookups, just iterated services once and find the set of used ports in // allocation range. We could maintain this state permanently in agent but // it doesn't seem to be necessary - even with thousands of services this is // not expensive to compute. usedPorts := make(map[int]struct{}) for _, otherNS := range a.State.Services() { // Check if other port is in auto-assign range if otherNS.Port >= a.config.ConnectSidecarMinPort && otherNS.Port <= a.config.ConnectSidecarMaxPort { if otherNS.ID == sidecar.ID { // This sidecar is already registered with an auto-port and is just // being updated so pick the same port as before rather than allocate // a new one. sidecar.Port = otherNS.Port break } usedPorts[otherNS.Port] = struct{}{} } // Note that the proxy might already be registered with a port that was // not in the auto range or the auto range has moved. In either case we // want to allocate a new one so it's no different from ignoring that it // already exists as we do now. } // Check we still need to assign a port and didn't find we already had one // allocated. if sidecar.Port < 1 { // Iterate until we find lowest unused port for p := a.config.ConnectSidecarMinPort; p <= a.config.ConnectSidecarMaxPort; p++ { _, used := usedPorts[p] if !used { sidecar.Port = p break } } } } // If no ports left (or auto ports disabled) fail if sidecar.Port < 1 { // If ports are set to zero explicitly, config builder switches them to // `-1`. In this case don't show the actual values since we don't know what // was actually in config (zero or negative) and it might be confusing, we // just know they explicitly disabled auto assignment. if a.config.ConnectSidecarMinPort < 1 || a.config.ConnectSidecarMaxPort < 1 { return nil, nil, "", fmt.Errorf("no port provided for sidecar_service " + "and auto-assignment disabled in config") } return nil, nil, "", fmt.Errorf("no port provided for sidecar_service and none "+ "left in the configured range [%d, %d]", a.config.ConnectSidecarMinPort, a.config.ConnectSidecarMaxPort) } // Setup checks checks, err := ns.Connect.SidecarService.CheckTypes() if err != nil { return nil, nil, "", err } // Setup default check if none given if len(checks) < 1 { checks = []*structs.CheckType{ &structs.CheckType{ Name: "Connect Sidecar Listening", // Default to localhost rather than agent/service public IP. The checks // can always be overridden if a non-loopback IP is needed. TCP: fmt.Sprintf("127.0.0.1:%d", sidecar.Port), Interval: 10 * time.Second, }, &structs.CheckType{ Name: "Connect Sidecar Aliasing " + ns.ID, AliasService: ns.ID, }, } } return sidecar, checks, token, nil }