add log command

cmd/ipfs/ipfs.go

@@ -63,6 +63,7 @@ Use "ipfs help <command>" for more information about a command.
 		cmdIpfsBootstrap,
 		cmdIpfsDiag,
 		cmdIpfsBlock,
+		cmdIpfsLog,
 	},
 	Flag: *flag.NewFlagSet("ipfs", flag.ExitOnError),
 }

cmd/ipfs/log.go

+package main
+
+import (
+	flag "github.com/jbenet/go-ipfs/Godeps/_workspace/src/github.com/gonuts/flag"
+	commander "github.com/jbenet/go-ipfs/Godeps/_workspace/src/github.com/jbenet/commander"
+	"github.com/jbenet/go-ipfs/core/commands"
+)
+
+var cmdIpfsLog = &commander.Command{
+	UsageLine: "log",
+	Short:     "switch logging levels of the daemon",
+	Long: `ipfs log - manipulate raw ipfs blocks
+
+    ipfs log dht error       - log error messages from the dht subsystem
+    ipfs log merkledag debug - print debug output from the merkledag subsystem
+
+
+ipfs block is a utility command used to change the logging output of a running daemon.`,
+	Run:  logCmd,
+	Flag: *flag.NewFlagSet("ipfs-log", flag.ExitOnError),
+}
+
+var logCmd = makeCommand(command{
+	name:   "log",
+	args:   2,
+	flags:  nil,
+	online: true,
+	cmdFn:  commands.Log,
+})

core/commands/log.go

+package commands
+
+import (
+	"io"
+
+	"github.com/jbenet/go-ipfs/core"
+	u "github.com/jbenet/go-ipfs/util"
+)
+
+// Log changes the log level of a subsystem
+func Log(n *core.IpfsNode, args []string, opts map[string]interface{}, out io.Writer) error {
+	if err := u.SetLogLevel(args[0], args[1]); err != nil {
+		return err
+	}
+
+	log.Info("Changed Log of '%q' to '%q'", args[0], args[1])
+	return nil
+}

daemon/daemon.go

@@ -137,6 +137,8 @@ func (dl *DaemonListener) handleConnection(conn manet.Conn) {
 		err = commands.BlockGet(dl.node, command.Args, command.Opts, conn)
 	case "blockPut":
 		err = commands.BlockPut(dl.node, command.Args, command.Opts, conn)
+	case "log":
+		err = commands.Log(dl.node, command.Args, command.Opts, conn)
 	default:
 		err = fmt.Errorf("Invalid Command: '%s'", command.Command)
 	}

util/log.go

@@ -60,9 +60,19 @@ func SetAllLoggers(lvl logging.Level) {
 	}
 }
 
-// Logger retrieves a particular logger + initializes it at a particular level
+// Logger retrieves a particular logger
 func Logger(name string) *logging.Logger {
 	log := logging.MustGetLogger(name)
 	loggers[name] = log
 	return log
 }
+
+// SetLogLevel changes the log level of a specific subsystem
+func SetLogLevel(name, level string) error {
+	_, ok := loggers[name]
+	if !ok {
+		return ErrNoSuchLogger
+	}
+
+	return ErrNotImplemented
+}

util/util.go

@@ -33,6 +33,9 @@ var ErrSearchIncomplete = errors.New("Error: Search Incomplete.")
 // ErrNotFound is returned when a search fails to find anything
 var ErrNotFound = ds.ErrNotFound
 
+// ErrNoSuchLogger is returned when the util pkg is asked for a non existant logger
+var ErrNoSuchLogger = errors.New("Error: No such logger")
+
 // TildeExpansion expands a filename, which may begin with a tilde.
 func TildeExpansion(filename string) (string, error) {
 	return homedir.Expand(filename)