package main // A note on the origin of the name. // http://en.wikipedia.org/wiki/Barak // TODO: Nonrepudiable command log import ( "errors" "flag" "fmt" "io" "io/ioutil" "net/http" "os" "reflect" "sync" "time" "github.com/tendermint/tendermint/binary" . "github.com/tendermint/tendermint/cmd/barak/types" . "github.com/tendermint/tendermint/common" pcm "github.com/tendermint/tendermint/process" "github.com/tendermint/tendermint/rpc" ) var Routes = map[string]*rpc.RPCFunc{ "status": rpc.NewRPCFunc(Status, []string{}), "run": rpc.NewRPCFunc(Run, []string{"auth_command"}), // NOTE: also, two special non-JSONRPC routes called "download" and "upload" } type Options struct { Validators []Validator ListenAddress string StartNonce uint64 } // Global instance var barak = struct { mtx sync.Mutex pid int nonce uint64 processes map[string]*pcm.Process validators []Validator rootDir string }{ mtx: sync.Mutex{}, pid: os.Getpid(), nonce: 0, processes: make(map[string]*pcm.Process), validators: nil, rootDir: "", } func main() { fmt.Printf("New Barak Process (PID: %d)\n", os.Getpid()) // read flags to change options file. var optionsBytes []byte var optionsFile string var err error flag.StringVar(&optionsFile, "options-file", "", "Read options from file instead of stdin") flag.Parse() if optionsFile != "" { optionsBytes, err = ioutil.ReadFile(optionsFile) } else { optionsBytes, err = ioutil.ReadAll(os.Stdin) } if err != nil { panic(Fmt("Error reading input: %v", err)) } options := binary.ReadJSON(&Options{}, optionsBytes, &err).(*Options) if err != nil { panic(Fmt("Error parsing input: %v", err)) } barak.nonce = options.StartNonce barak.validators = options.Validators barak.rootDir = os.Getenv("BRKROOT") if barak.rootDir == "" { barak.rootDir = os.Getenv("HOME") + "/.barak" } err = EnsureDir(barak.rootDir) if err != nil { panic(Fmt("Error creating barak rootDir: %v", err)) } // Write pid to file. err = AtomicWriteFile(barak.rootDir+"/pidfile", []byte(Fmt("%v", barak.pid))) if err != nil { panic(Fmt("Error writing pidfile: %v", err)) } // Debug. fmt.Printf("Options: %v\n", options) fmt.Printf("Barak: %v\n", barak) // Start rpc server. mux := http.NewServeMux() mux.HandleFunc("/download", ServeFile) // TODO: mux.HandleFunc("/upload", UploadFile) rpc.RegisterRPCFuncs(mux, Routes) rpc.StartHTTPServer(options.ListenAddress, mux) TrapSignal(func() { fmt.Println("Barak shutting down") }) } //------------------------------------------------------------------------------ // RPC functions func Status() (*ResponseStatus, error) { barak.mtx.Lock() pid := barak.pid nonce := barak.nonce validators := barak.validators barak.mtx.Unlock() return &ResponseStatus{ Pid: pid, Nonce: nonce, Validators: validators, }, nil } func Run(authCommand AuthCommand) (interface{}, error) { command, err := parseValidateCommand(authCommand) if err != nil { return nil, err } log.Info(Fmt("Run() received command %v:\n%v", reflect.TypeOf(command), command)) // Issue command switch c := command.(type) { case CommandRunProcess: return RunProcess(c.Wait, c.Label, c.ExecPath, c.Args, c.Input) case CommandStopProcess: return StopProcess(c.Label, c.Kill) case CommandListProcesses: return ListProcesses() default: return nil, errors.New("Invalid endpoint for command") } } func parseValidateCommandStr(authCommandStr string) (Command, error) { var err error authCommand := binary.ReadJSON(AuthCommand{}, []byte(authCommandStr), &err).(AuthCommand) if err != nil { fmt.Printf("Failed to parse auth_command") return nil, errors.New("AuthCommand parse error") } return parseValidateCommand(authCommand) } func parseValidateCommand(authCommand AuthCommand) (Command, error) { commandJSONStr := authCommand.CommandJSONStr signatures := authCommand.Signatures // Validate commandJSONStr if !validate([]byte(commandJSONStr), barak.validators, signatures) { fmt.Printf("Failed validation attempt") return nil, errors.New("Validation error") } // Parse command var err error command := binary.ReadJSON(NoncedCommand{}, []byte(commandJSONStr), &err).(NoncedCommand) if err != nil { fmt.Printf("Failed to parse command") return nil, errors.New("Command parse error") } // Prevent replays if barak.nonce+1 != command.Nonce { return nil, errors.New("Replay error") } else { barak.nonce += 1 } return command.Command, nil } //------------------------------------------------------------------------------ // RPC base commands // WARNING Not validated, do not export to routes. func RunProcess(wait bool, label string, execPath string, args []string, input string) (*ResponseRunProcess, error) { barak.mtx.Lock() // First, see if there already is a process labeled 'label' existing := barak.processes[label] if existing != nil && existing.EndTime.IsZero() { barak.mtx.Unlock() return nil, fmt.Errorf("Process already exists: %v", label) } // Otherwise, create one. err := EnsureDir(barak.rootDir + "/outputs") if err != nil { return nil, fmt.Errorf("Failed to create outputs dir: %v", err) } outPath := Fmt("%v/outputs/%v_%v.out", barak.rootDir, label, time.Now().Format("2006_01_02_15_04_05_MST")) proc, err := pcm.Create(pcm.ProcessModeDaemon, label, execPath, args, input, outPath) if err == nil { barak.processes[label] = proc } barak.mtx.Unlock() if err != nil { return nil, err } if wait { <-proc.WaitCh output := pcm.ReadOutput(proc) fmt.Println("Read output", output) if proc.ExitState == nil { return &ResponseRunProcess{ Success: true, Output: output, }, nil } else { return &ResponseRunProcess{ Success: proc.ExitState.Success(), // Would be always false? Output: output, }, nil } } else { return &ResponseRunProcess{ Success: true, Output: "", }, nil } } func StopProcess(label string, kill bool) (*ResponseStopProcess, error) { barak.mtx.Lock() proc := barak.processes[label] barak.mtx.Unlock() if proc == nil { return nil, fmt.Errorf("Process does not exist: %v", label) } err := pcm.Stop(proc, kill) return &ResponseStopProcess{}, err } func ListProcesses() (*ResponseListProcesses, error) { var procs = []*pcm.Process{} barak.mtx.Lock() fmt.Println("Processes: %v", barak.processes) for _, proc := range barak.processes { procs = append(procs, proc) } barak.mtx.Unlock() return &ResponseListProcesses{ Processes: procs, }, nil } func ServeFile(w http.ResponseWriter, req *http.Request) { authCommandStr := req.FormValue("auth_command") command, err := parseValidateCommandStr(authCommandStr) if err != nil { http.Error(w, Fmt("Invalid command: %v", err), 400) } serveCommand, ok := command.(CommandServeFile) if !ok { http.Error(w, "Invalid command", 400) } path := serveCommand.Path if path == "" { http.Error(w, "Must specify path", 400) return } file, err := os.Open(path) if err != nil { http.Error(w, Fmt("Error opening file: %v. %v", path, err), 400) return } _, err = io.Copy(w, file) if err != nil { fmt.Fprintf(os.Stderr, Fmt("Error serving file: %v. %v", path, err)) return } }