remote/main.go

   1 // Helper copied to the remote host to run commands and deploy configuration
   2
   3 // SPDX-License-Identifier: GPL-3.0-or-later
   4 // Copyright (C) 2021-2024  Simon Ruderich
   5
   6 package remote
   7
   8 import (
   9         "fmt"
  10         "log"
  11         "os"
  12
  13         "golang.org/x/term"
  14
  15         "ruderich.org/simon/safcm"
  16         "ruderich.org/simon/safcm/remote/ainsl"
  17         "ruderich.org/simon/safcm/remote/info"
  18         "ruderich.org/simon/safcm/remote/run"
  19         "ruderich.org/simon/safcm/remote/sync"
  20 )
  21
  22 func usage() {
  23         log.Fatalf("usage: %[1]s sync\n"+
  24                 "usage: %[1]s ainsl [options] <path> <line>",
  25                 os.Args[0])
  26 }
  27
  28 func Main() {
  29         // Timestamps are added by `safcm`
  30         log.SetFlags(0)
  31
  32         if len(os.Args) < 2 {
  33                 usage()
  34         }
  35
  36         var err error
  37         switch os.Args[1] {
  38         case "sync":
  39                 if len(os.Args) != 2 {
  40                         usage()
  41                 }
  42                 err = mainLoop()
  43         case "ainsl":
  44                 err = ainsl.Main(os.Args)
  45         default:
  46                 usage()
  47         }
  48
  49         if err != nil {
  50                 log.Fatalf("%s: %v", os.Args[0], err)
  51         }
  52 }
  53
  54 func mainLoop() error {
  55         if term.IsTerminal(int(os.Stdin.Fd())) ||
  56                 term.IsTerminal(int(os.Stdout.Fd())) {
  57                 return fmt.Errorf("sync should only be called from `safcm` " +
  58                         "(redirect stdin/stdout to circumvent this check)")
  59         }
  60
  61         conn := safcm.NewGobConn(os.Stdin, os.Stdout)
  62
  63         var logLevel safcm.LogLevel
  64         logFunc := func(level safcm.LogLevel, msg string) {
  65                 if logLevel >= level {
  66                         // Handling errors here is complex and quite verbose.
  67                         // If it happens the connection is gone anyway so skip
  68                         // the error handling.
  69                         conn.Send(safcm.MsgLog{ //nolint:errcheck
  70                                 Level: level,
  71                                 Text:  msg,
  72                         })
  73                 }
  74         }
  75
  76         var quitResp safcm.MsgQuitResp
  77         for {
  78                 x, err := conn.Recv()
  79                 if err != nil {
  80                         return err
  81                 }
  82
  83                 var resp safcm.Msg
  84                 switch x := x.(type) {
  85                 case safcm.MsgInfoReq:
  86                         logLevel = x.LogLevel // set log level globally
  87                         resp = info.Handle(x, run.ExecRunner{}, logFunc)
  88                 case safcm.MsgSyncReq:
  89                         resp = sync.Handle(x, run.ExecRunner{}, logFunc)
  90                 case safcm.MsgQuitReq:
  91                         resp = quitResp
  92                 default:
  93                         return fmt.Errorf("unsupported message %#v", x)
  94                 }
  95
  96                 err = conn.Send(resp)
  97                 if err != nil {
  98                         return err
  99                 }
 100                 if resp == quitResp {
 101                         break
 102                 }
 103         }
 104         return nil
 105 }