wings/server/environment.go
2019-12-21 23:23:56 -08:00

80 lines
2.8 KiB
Go

package server
import (
"os"
)
// Defines the basic interface that all environments need to implement so that
// a server can be properly controlled.
type Environment interface {
// Returns the name of the environment.
Type() string
// Determines if the environment is currently active and running a server process
// for this specific server instance.
IsRunning() (bool, error)
// Performs an update of server resource limits without actually stopping the server
// process. This only executes if the environment supports it, otherwise it is
// a no-op.
InSituUpdate() error
// Runs before the environment is started. If an error is returned starting will
// not occur, otherwise proceeds as normal.
OnBeforeStart() error
// Starts a server instance. If the server instance is not in a state where it
// can be started an error should be returned.
Start() error
// Stops a server instance. If the server is already stopped an error should
// not be returned.
Stop() error
// Determines if the server instance exists. For example, in a docker environment
// this should confirm that the container is created and in a bootable state. In
// a basic CLI environment this can probably just return true right away.
Exists() (bool, error)
// Terminates a running server instance using the provided signal. If the server
// is not running no error should be returned.
Terminate(signal os.Signal) error
// Destroys the environment removing any containers that were created (in Docker
// environments at least).
Destroy() error
// Returns the exit state of the process. The first result is the exit code, the second
// determines if the process was killed by the system OOM killer.
ExitState() (uint32, bool, error)
// Creates the necessary environment for running the server process. For example,
// in the Docker environment create will create a new container instance for the
// server.
Create() error
// Attaches to the server console environment and allows piping the output to a
// websocket or other internal tool to monitor output. Also allows you to later
// send data into the environment's stdin.
Attach() error
// Follows the output from the server console and will begin piping the output to
// the server's emitter.
FollowConsoleOutput() error
// Sends the provided command to the running server instance.
SendCommand(string) error
// Reads the log file for the process from the end backwards until the provided
// number of bytes is met.
Readlog(int64) ([]string, error)
// Polls the given environment for resource usage of the server when the process
// is running.
EnableResourcePolling() error
// Disables the polling operation for resource usage and sets the required values
// to 0 in the server resource usage struct.
DisableResourcePolling() error
}