package server import ( "fmt" "github.com/creasty/defaults" "github.com/patrickmn/go-cache" "github.com/pkg/errors" "github.com/pterodactyl/wings/api" "github.com/pterodactyl/wings/config" "github.com/remeh/sizedwaitgroup" "go.uber.org/zap" "gopkg.in/yaml.v2" "io/ioutil" "os" "path" "strings" "sync" "time" ) var servers *Collection func GetServers() *Collection { return servers } // High level definition for a server instance being controlled by Wings. type Server struct { // The unique identifier for the server that should be used when referencing // it aganist the Panel API (and internally). This will be used when naming // docker containers as well as in log output. Uuid string `json:"uuid"` // Wether or not the server is in a suspended state. Suspended servers cannot // be started or modified except in certain scenarios by an admin user. Suspended bool `json:"suspended"` // The power state of the server. State string `default:"offline" json:"state"` // The command that should be used when booting up the server instance. Invocation string `json:"invocation"` // An array of environment variables that should be passed along to the running // server process. EnvVars map[string]string `json:"environment" yaml:"environment"` CrashDetection CrashDetection `json:"crash_detection" yaml:"crash_detection"` Build BuildSettings `json:"build"` Allocations Allocations `json:"allocations"` Environment Environment `json:"-" yaml:"-"` Filesystem Filesystem `json:"-" yaml:"-"` Resources ResourceUsage `json:"resources" yaml:"-"` Container struct { // Defines the Docker image that will be used for this server Image string `json:"image,omitempty"` // If set to true, OOM killer will be disabled on the server's Docker container. // If not present (nil) we will default to disabling it. OomDisabled bool `default:"true" json:"oom_disabled" yaml:"oom_disabled"` } `json:"container,omitempty"` // Server cache used to store frequently requested information in memory and make // certain long operations return faster. For example, FS disk space usage. Cache *cache.Cache `json:"-" yaml:"-"` // All of the registered event listeners for this server instance. listeners EventListeners // Defines the process configuration for the server instance. This is dynamically // fetched from the Pterodactyl Server instance each time the server process is // started, and then cached here. processConfiguration *api.ProcessConfiguration // Internal mutex used to block actions that need to occur sequentially, such as // writing the configuration to the disk. mutex *sync.Mutex } // The build settings for a given server that impact docker container creation and // resource limits for a server instance. type BuildSettings struct { // The total amount of memory in megabytes that this server is allowed to // use on the host system. MemoryLimit int64 `json:"memory_limit" yaml:"memory"` // The amount of additional swap space to be provided to a container instance. Swap int64 `json:"swap"` // The relative weight for IO operations in a container. This is relative to other // containers on the system and should be a value between 10 and 1000. IoWeight uint16 `json:"io_weight" yaml:"io"` // The percentage of CPU that this instance is allowed to consume relative to // the host. A value of 200% represents complete utilization of two cores. This // should be a value between 1 and THREAD_COUNT * 100. CpuLimit int64 `json:"cpu_limit" yaml:"cpu"` // The amount of disk space in megabytes that a server is allowed to use. DiskSpace int64 `json:"disk_space" yaml:"disk"` } // Converts the CPU limit for a server build into a number that can be better understood // by the Docker environment. If there is no limit set, return -1 which will indicate to // Docker that it has unlimited CPU quota. func (b *BuildSettings) ConvertedCpuLimit() int64 { if b.CpuLimit == 0 { return -1 } return b.CpuLimit * 1000 } // Returns the amount of swap available as a total in bytes. This is returned as the amount // of memory available to the server initially, PLUS the amount of additional swap to include // which is the format used by Docker. func (b *BuildSettings) ConvertedSwap() int64 { if b.Swap < 0 { return -1 } return (b.Swap * 1000000) + (b.MemoryLimit * 1000000) } // Defines the allocations available for a given server. When using the Docker environment // driver these correspond to mappings for the container that allow external connections. type Allocations struct { // Defines the default allocation that should be used for this server. This is // what will be used for {SERVER_IP} and {SERVER_PORT} when modifying configuration // files or the startup arguments for a server. DefaultMapping struct { Ip string `json:"ip"` Port int `json:"port"` } `json:"default" yaml:"default"` // Mappings contains all of the ports that should be assigned to a given server // attached to the IP they correspond to. Mappings map[string][]int `json:"mappings"` } // Iterates over a given directory and loads all of the servers listed before returning // them to the calling function. func LoadDirectory(dir string, cfg *config.SystemConfiguration) error { // We could theoretically use a standard wait group here, however doing // that introduces the potential to crash the program due to too many // open files. This wouldn't happen on a small setup, but once the daemon is // handling many servers you run that risk. // // For now just process 10 files at a time, that should be plenty fast to // read and parse the YAML. We should probably make this configurable down // the road to help big instances scale better. wg := sizedwaitgroup.New(10) f, err := ioutil.ReadDir(dir) if err != nil { return err } servers = NewCollection(nil) for _, file := range f { if !strings.HasSuffix(file.Name(), ".yml") || file.IsDir() { continue } wg.Add() // For each of the YAML files we find, parse it and create a new server // configuration object that can then be returned to the caller. go func(file os.FileInfo) { defer wg.Done() b, err := ioutil.ReadFile(path.Join(dir, file.Name())) if err != nil { zap.S().Errorw("failed to read server configuration file, skipping...", zap.String("server", file.Name()), zap.Error(err)) return } s, err := FromConfiguration(b, cfg) if err != nil { if IsServerDoesNotExistError(err) { zap.S().Infow("server does not exist on remote system", zap.String("server", file.Name())) } else { zap.S().Errorw("failed to parse server configuration, skipping...", zap.String("server", file.Name()), zap.Error(err)) } return } servers.Add(s) }(file) } // Wait until we've processed all of the configuration files in the directory // before continuing. wg.Wait() return nil } // Initializes the default required internal struct components for a Server. func (s *Server) Init() { s.listeners = make(map[string][]EventListenerFunction) s.mutex = &sync.Mutex{} } // Initalizes a server using a data byte array. This will be marshaled into the // given struct using a YAML marshaler. This will also configure the given environment // for a server. func FromConfiguration(data []byte, cfg *config.SystemConfiguration) (*Server, error) { s := new(Server) if err := defaults.Set(s); err != nil { return nil, err } s.Init() if err := yaml.Unmarshal(data, s); err != nil { return nil, err } s.AddEventListeners() withConfiguration := func(e *DockerEnvironment) { e.User = cfg.User.Uid e.TimezonePath = cfg.TimezonePath e.Server = s } // Right now we only support a Docker based environment, so I'm going to hard code // this logic in. When we're ready to support other environment we'll need to make // some modifications here obviously. var env Environment if t, err := NewDockerEnvironment(withConfiguration); err == nil { env = t } else { return nil, err } s.Environment = env s.Cache = cache.New(time.Minute*10, time.Minute*15) s.Filesystem = Filesystem{ Configuration: cfg, Server: s, } s.Resources = ResourceUsage{} // This is also done when the server is booted, however we need to account for instances // where the server is already running and the Daemon reboots. In those cases this will // allow us to you know, stop servers. if cfg.SyncServersOnBoot { if err := s.Sync(); err != nil { return nil, err } } return s, nil } // Syncs the state of the server on the Panel with Wings. This ensures that we're always // using the state of the server from the Panel and allows us to not require successful // API calls to Wings to do things. // // This also means mass actions can be performed against servers on the Panel and they // will automatically sync with Wings when the server is started. func (s *Server) Sync() error { cfg, rerr, err := s.GetProcessConfiguration() if err != nil || rerr != nil { if err != nil { return errors.WithStack(err) } if rerr.Status == "404" { return &serverDoesNotExist{} } return errors.New(rerr.String()) } // Update the data structure and persist it to the disk. if err:= s.UpdateDataStructure(cfg.Settings, false); err != nil { return errors.WithStack(err) } s.processConfiguration = cfg.ProcessConfiguration return nil } // Reads the log file for a server up to a specified number of bytes. func (s *Server) ReadLogfile(len int64) ([]string, error) { return s.Environment.Readlog(len) } // Determine if the server is bootable in it's current state or not. This will not // indicate why a server is not bootable, only if it is. func (s *Server) IsBootable() bool { exists, _ := s.Environment.Exists() return exists } // Initalizes a server instance. This will run through and ensure that the environment // for the server is setup, and that all of the necessary files are created. func (s *Server) CreateEnvironment() error { return s.Environment.Create() } const ( ProcessOfflineState = "offline" ProcessStartingState = "starting" ProcessRunningState = "running" ProcessStoppingState = "stopping" ) // Sets the state of the server internally. This function handles crash detection as // well as reporting to event listeners for the server. func (s *Server) SetState(state string) error { if state != ProcessOfflineState && state != ProcessStartingState && state != ProcessRunningState && state != ProcessStoppingState { return errors.New(fmt.Sprintf("invalid server state received: %s", state)) } prevState := s.State s.State = state // Persist this change to the disk immediately so that should the Daemon be stopped or // crash we can immediately restore the server state. // // This really only makes a difference if all of the Docker containers are also stopped, // but this was a highly requested feature and isn't hard to work with, so lets do it. // // We also get the benefit of server status changes always propagating corrected configurations // to the disk should we forget to do it elsewhere. go func(server *Server) { if _, err := server.WriteConfigurationToDisk(); err != nil { zap.S().Warnw("failed to write server state change to disk", zap.String("server", server.Uuid), zap.Error(err)) } }(s) zap.S().Debugw("saw server status change event", zap.String("server", s.Uuid), zap.String("status", state)) // Emit the event to any listeners that are currently registered. s.Emit(StatusEvent, s.State) // If server was in an online state, and is now in an offline state we should handle // that as a crash event. In that scenario, check the last crash time, and the crash // counter. // // In the event that we have passed the thresholds, don't do anything, otherwise // automatically attempt to start the process back up for the user. This is done in a // seperate thread as to not block any actions currently taking place in the flow // that called this function. if (prevState == ProcessStartingState || prevState == ProcessRunningState) && s.State == ProcessOfflineState { zap.S().Infow("detected server as entering a potentially crashed state; running handler", zap.String("server", s.Uuid)) go func(server *Server) { if err := server.handleServerCrash(); err != nil { if IsTooFrequentCrashError(err) { zap.S().Infow("did not restart server after crash; occurred too soon after last", zap.String("server", server.Uuid)) } else { zap.S().Errorw("failed to handle server crash state", zap.String("server", server.Uuid), zap.Error(err)) } } }(s) } return nil } // Gets the process configuration data for the server. func (s *Server) GetProcessConfiguration() (*api.ServerConfigurationResponse, *api.RequestError, error) { return api.NewRequester().GetServerConfiguration(s.Uuid) }