rafthub

type Backend int

type Config struct {

	// Name gives the server application a name. Default "rafthub-app"
	Name string

	// Version of the application. Default "0.0.0"
	Version string

	// GitSHA of the application.
	GitSHA string

	// Flag is used to manage the application startup flags.
	Flag struct {
		// Custom tells Main to not automatically parse the application startup
		// flags. When set it is up to the user to parse the os.Args manually
		// or with a different library.
		Custom bool
		// Usage is an optional function that allows for altering the usage
		// message.
		Usage func(usage string) string
		// PreParse is an optional function that allows for adding command line
		// flags before the user flags are parsed.
		PreParse func()
		// PostParse is an optional function that fires after user flags are
		// parsed.
		PostParse func()
	}

	// Snapshot fires when a snapshot
	Snapshot func(data interface{}) (Snapshot, error)

	// Restore returns a data object that is fully restored from the previous
	// snapshot using the input Reader. A restore operation on happens once,
	// if needed, at the start of the application.
	Restore func(rd io.Reader) (data interface{}, err error)

	// UseJSONSnapshots is a convienence field that tells the machine to use
	// JSON as the format for all snapshots and restores. This may be good for
	// small simple data models which have types that can be fully marshalled
	// into JSON, ie. all imporant data fields need to exportable (Capitalized).
	// For more complicated or specialized data, it's proabably best to assign
	// custom functions to the Config.Snapshot and Config.Restore fields.
	// It's invalid to set this field while also setting Snapshot and/or
	// Restore. Default false
	UseJSONSnapshots bool

	// Tick fires at regular intervals as specified by TickDelay. This function
	// can be used to make updates to the database.
	Tick func(m Machine)

	// DataDirReady is an optional callback function that fires containing the
	// path to the directory where all the logs and snapshots are stored.
	DataDirReady func(dir string)

	// LogReady is an optional callback function that fires when the logger has
	// been initialized. The logger is can be safely used concurrently.
	LogReady func(log Logger)

	// ServerReady is an optional callback function that fires when the server
	// socket is listening and is ready to accept incoming connections. The
	// network address, auth, and tls-config are provided to allow for
	// background connections to be made to self, if desired.
	ServerReady func(addr, auth string, tlscfg *tls.Config)

	// ConnOpened is an optional callback function that fires when a new
	// network connection was opened on this machine. You can accept or deny
	// the connection, and optionally provide a client-specific context that
	// stick around until the connection is closed with ConnClosed.
	ConnOpened func(addr string) (context interface{}, accept bool)

	// ConnClosed is an optional callback function that fires when a network
	// connection has been closed on this machine.
	ConnClosed func(context interface{}, addr string)

	LocalTime   bool          // default false
	TickDelay   time.Duration // default 200ms
	BackupPath  string        // default ""
	InitialData interface{}   // default nil
	NodeID      string        // default "1"
	Addr        string        // default ":11001"
	DataDir     string        // default "data"
	LogOutput   io.Writer     // default os.Stderr
	LogLevel    string        // default "notice"
	JoinAddr    string        // default ""
	Backend     Backend       // default LevelDB
	NoSync      bool          // default false
	OpenReads   bool          // default false
	MaxPool     int           // default 8
	TLSCertPath string        // default ""
	TLSKeyPath  string        // default ""
	Auth        string        // default ""
	Advertise   string        // default ""
	TryErrors   bool          // default false (return TRY instead of MOVED)
	// contains filtered or unexported fields
}

type FilterArgs []string

type Hijack func(s Service, conn HijackedConn)

type HijackedConn interface {
	// RemoteAddr is the connection remote tcp address.
	RemoteAddr() string
	// ReadCommands is an iterator function that reads pipelined commands.
	// Returns a error when the connection encountared and error.
	ReadCommands(func(args []string) bool) error
	// ReadCommand reads one command at a time.
	ReadCommand() (args []string, err error)
	// WriteAny writes any type to the write buffer using the format rules that
	// are defined by the original Service.
	WriteAny(v interface{})
	// WriteRaw writes raw data to the write buffer.
	WriteRaw(data []byte)
	// Flush the write write buffer and send data to the connection.
	Flush() error
	// Close the connection
	Close() error
}

type Logger interface {
	Debugf(format string, args ...interface{})
	Debug(args ...interface{})
	Debugln(args ...interface{})
	Verbf(format string, args ...interface{})
	Verb(args ...interface{})
	Verbln(args ...interface{})
	Noticef(format string, args ...interface{})
	Notice(args ...interface{})
	Noticeln(args ...interface{})
	Printf(format string, args ...interface{})
	Print(args ...interface{})
	Println(args ...interface{})
	Warningf(format string, args ...interface{})
	Warning(args ...interface{})
	Warningln(args ...interface{})
	Fatalf(format string, args ...interface{})
	Fatal(args ...interface{})
	Fatalln(args ...interface{})
	Panicf(format string, args ...interface{})
	Panic(args ...interface{})
	Panicln(args ...interface{})
	Errorf(format string, args ...interface{})
	Error(args ...interface{})
	Errorln(args ...interface{})
}

type Machine interface {
	// Data is the original user data interface that was assigned at startup.
	// It's safe to alter the data in this interface while inside a Write
	// command, but it's only safe to read from this interface for Read
	// commands.
	// Returns nil for Intermediate Commands.
	Data() interface{}
	// Now generates a stable timestamp that is synced with internet time
	// and for Write commands is always monotonical increasing. It's made to
	// be a trusted source of time for performing operations on the user data.
	// Always use this function instead of the builtin time.Now().
	// Returns nil for Intermediate Commands.
	Now() time.Time
	// Rand is a random number generator that must be used instead of the
	// standard Go packages `crypto/rand` and `math/rand`. For Write commands
	// the values returned from this generator are crypto seeded, guaranteed
	// to be reproduced in exact order when the server restarts, and identical
	// across all machines in the cluster. The underlying implementation is
	// PCG. Check out http://www.pcg-random.org/ for more information.
	// Returns nil for Intermediate Commands.
	Rand() Rand
	// Utility logger for printing information to the local server log.
	Log() Logger
	// Context returns the connection context that was defined in from the
	// Config.ConnOpened callback. Only available for Intermediate commands.
	// Returns nil for Read and Write Commands.
	Context() interface{}
}

type Message struct {
	// Args are the original command arguments.
	Args []string
	// Resp is the command reponse, if not an error.
	Resp interface{}
	// Err is the command error, if not successful.
	Err error
	// Elapsed is the amount of time that the command took to process.
	Elapsed time.Duration
	// Addr is the remote TCP address of the connection that generated
	// this message.
	Addr string
}

type Monitor interface {
	// Send a message to observers
	Send(msg Message)
	// NewObjser returns a new Observer containing a channel that will send the
	// messages for every command processed by the service.
	// Stop the observer to release associated resources.
	NewObserver() Observer
}

type Observer interface {
	Stop()
	C() <-chan Message
}

type Rand interface {
	Int() int
	Uint64() uint64
	Uint32() uint32
	Float64() float64
	Read([]byte) (n int, err error)
}

type Receiver interface {
	Recv() (interface{}, time.Duration, error)
}

type SendOptions struct {
	Context        interface{}
	From           interface{}
	AllowOpenReads bool
	DenyOpenReads  bool
}

type Service interface {
	// Send a command with args from a client
	Send(args []string, opts *SendOptions) Receiver
	// Auth authorizes a client
	Auth(auth string) error
	// Log is shared logger
	Log() Logger
	// Monitor returns a service monitor for observing client commands.
	Monitor() Monitor
	// Opened
	Opened(addr string) (context interface{}, accept bool)
	// Closed
	Closed(context interface{}, addr string)
}

type Snapshot interface {
	Persist(io.Writer) error
	Done(path string)
}