feat: add query functionality to log level command (#10885)

* feat: update log level command to show log levels
* test: add log level tests
* update TestCommands test
* docs: relation to GOLOG_LOG_LEVEL
* chore: update to latest go-log
* fix: do not output single subsystem name in CLI
* test: explicit subsystem request dont output subsystem
* LevelFromString renamed to Parse
* Modify `ipfs log level` 
* Denote default level with sdubsystem name '(defult)'.
* make "*" an dalias for "all".  Test to make sure both work the same.

cmd/ipfs/kubo/start.go

@@ -214,8 +214,8 @@ func insideGUI() bool {
 func checkDebug(req *cmds.Request) {
 	// check if user wants to debug. option OR env var.
 	debug, _ := req.Options["debug"].(bool)
-	ipfsLogLevel, _ := logging.LevelFromString(os.Getenv("IPFS_LOGGING")) // IPFS_LOGGING is deprecated
-	goLogLevel, _ := logging.LevelFromString(os.Getenv("GOLOG_LOG_LEVEL"))
+	ipfsLogLevel, _ := logging.Parse(os.Getenv("IPFS_LOGGING")) // IPFS_LOGGING is deprecated
+	goLogLevel, _ := logging.Parse(os.Getenv("GOLOG_LOG_LEVEL"))
 
 	if debug || goLogLevel == logging.LevelDebug || ipfsLogLevel == logging.LevelDebug {
 		u.Debug = true

core/commands/log.go

@@ -3,16 +3,37 @@ package commands
 import (
 	"fmt"
 	"io"
+	"slices"
 
 	cmds "github.com/ipfs/go-ipfs-cmds"
 	logging "github.com/ipfs/go-log/v2"
 )
 
-// Golang os.Args overrides * and replaces the character argument with
-// an array which includes every file in the user's CWD. As a
-// workaround, we use 'all' instead. The util library still uses * so
-// we convert it at this step.
-var logAllKeyword = "all"
+const (
+	// allLogSubsystems is used to specify all log subsystems when setting the
+	// log level.
+	allLogSubsystems = "*"
+	// allLogSubsystemsAlias is a convenience alias for allLogSubsystems that
+	// doesn't require shell escaping.
+	allLogSubsystemsAlias = "all"
+	// defaultLogLevel is used to request and to identify the default log
+	// level.
+	defaultLogLevel = "default"
+	// defaultSubsystemKey is the subsystem name that is used to denote the
+	// default log level. We use parentheses for UI clarity to distinguish it
+	// from regular subsystem names.
+	defaultSubsystemKey = "(default)"
+	// logLevelOption is an option for the tail subcommand to select the log
+	// level to output.
+	logLevelOption = "log-level"
+	// noSubsystemSpecified is used when no subsystem argument is provided
+	noSubsystemSpecified = ""
+)
+
+type logLevelOutput struct {
+	Levels  map[string]string `json:",omitempty"`
+	Message string            `json:",omitempty"`
+}
 
 var LogCmd = &cmds.Command{
 	Helptext: cmds.HelpText{
@@ -39,46 +60,161 @@ system (not just for the daemon logs, but all commands):
 
 var logLevelCmd = &cmds.Command{
 	Helptext: cmds.HelpText{
-		Tagline: "Change the logging level.",
+		Tagline: "Change or get the logging level.",
 		ShortDescription: `
-Change the verbosity of one or all subsystems log output. This does not affect
-the event log.
+Get or change the logging level of one or all logging subsystems.
+
+This command provides a runtime alternative to the GOLOG_LOG_LEVEL
+environment variable for debugging and troubleshooting.
+
+UNDERSTANDING DEFAULT vs '*':
+
+The "default" level is the fallback used by unconfigured subsystems.
+You cannot set the default level directly - it only changes when you use '*'.
+
+The '*' wildcard represents ALL subsystems including the default level.
+Setting '*' changes everything at once, including the default.
+
+EXAMPLES - Getting levels:
+
+  ipfs log level              # Show only the default fallback level
+  ipfs log level all          # Show all subsystem levels (100+ lines)
+  ipfs log level core         # Show level for 'core' subsystem only
+
+EXAMPLES - Setting levels:
+
+  ipfs log level core debug   # Set 'core' to 'debug' (default unchanged)
+  ipfs log level all info     # Set ALL to 'info' (including default)
+  ipfs log level core default # Reset 'core' to use current default level
+
+WILDCARD OPTIONS:
+
+Use 'all' (convenient) or '*' (requires escaping) to affect all subsystems:
+  ipfs log level all debug    # Convenient - no shell escaping needed
+  ipfs log level '*' debug    # Equivalent but needs quotes: '*' or "*" or \*
+
+BEHAVIOR EXAMPLES:
+
+Initial state (all using default 'error'):
+  $ ipfs log level              => error
+  $ ipfs log level core         => error
+
+After setting one subsystem:
+  $ ipfs log level core debug
+  $ ipfs log level              => error (default unchanged!)
+  $ ipfs log level core         => debug (explicitly set)
+  $ ipfs log level dht          => error (still uses default)
+
+After setting everything with 'all':
+  $ ipfs log level all info
+  $ ipfs log level              => info (default changed!)
+  $ ipfs log level core         => info (all changed)
+  $ ipfs log level dht          => info (all changed)
+
+The 'default' keyword always refers to the current default level:
+  $ ipfs log level              => error
+  $ ipfs log level core default  # Sets core to 'error'
+  $ ipfs log level all info      # Changes default to 'info'
+  $ ipfs log level core default  # Now sets core to 'info'
 `,
 	},
 
 	Arguments: []cmds.Argument{
-		// TODO use a different keyword for 'all' because all can theoretically
-		// clash with a subsystem name
-		cmds.StringArg("subsystem", true, false, fmt.Sprintf("The subsystem logging identifier. Use '%s' for all subsystems.", logAllKeyword)),
-		cmds.StringArg("level", true, false, `The log level, with 'debug' the most verbose and 'fatal' the least verbose.
-			One of: debug, info, warn, error, dpanic, panic, fatal.
-		`),
+		cmds.StringArg("subsystem", false, false, fmt.Sprintf("The subsystem logging identifier. Use '%s' or '%s' to get or set the log level of all subsystems including the default. If not specified, only show the default log level.", allLogSubsystemsAlias, allLogSubsystems)),
+		cmds.StringArg("level", false, false, fmt.Sprintf("The log level, with 'debug' as the most verbose and 'fatal' the least verbose. Use '%s' to set to the current default level. One of: debug, info, warn, error, dpanic, panic, fatal, %s", defaultLogLevel, defaultLogLevel)),
 	},
 	NoLocal: true,
 	Run: func(req *cmds.Request, res cmds.ResponseEmitter, env cmds.Environment) error {
-		args := req.Arguments
-		subsystem, level := args[0], args[1]
+		var level, subsystem string
 
-		if subsystem == logAllKeyword {
-			subsystem = "*"
+		if len(req.Arguments) > 0 {
+			subsystem = req.Arguments[0]
+			if len(req.Arguments) > 1 {
+				level = req.Arguments[1]
+			}
+
+			// Normalize aliases to the canonical "*" form
+			if subsystem == allLogSubsystems || subsystem == allLogSubsystemsAlias {
+				subsystem = "*"
+			}
 		}
 
-		if err := logging.SetLogLevel(subsystem, level); err != nil {
-			return err
+		// If a level is specified, then set the log level.
+		if level != "" {
+			if level == defaultLogLevel {
+				level = logging.DefaultLevel().String()
+			}
+
+			if err := logging.SetLogLevel(subsystem, level); err != nil {
+				return err
+			}
+
+			s := fmt.Sprintf("Changed log level of '%s' to '%s'\n", subsystem, level)
+			log.Info(s)
+
+			return cmds.EmitOnce(res, &logLevelOutput{Message: s})
 		}
 
-		s := fmt.Sprintf("Changed log level of '%s' to '%s'\n", subsystem, level)
-		log.Info(s)
+		// Get the level for the requested subsystem.
+		switch subsystem {
+		case noSubsystemSpecified:
+			// Return the default log level
+			levelMap := map[string]string{logging.DefaultName: logging.DefaultLevel().String()}
+			return cmds.EmitOnce(res, &logLevelOutput{Levels: levelMap})
+		case allLogSubsystems, allLogSubsystemsAlias:
+			// Return levels for all subsystems (default behavior)
+			levels := logging.SubsystemLevelNames()
+
+			// Replace default subsystem key with defaultSubsystemKey.
+			levels[defaultSubsystemKey] = levels[logging.DefaultName]
+			delete(levels, logging.DefaultName)
+			return cmds.EmitOnce(res, &logLevelOutput{Levels: levels})
+		default:
+			// Return level for a specific subsystem.
+			level, err := logging.SubsystemLevelName(subsystem)
+			if err != nil {
+				return err
+			}
+			levelMap := map[string]string{subsystem: level}
+			return cmds.EmitOnce(res, &logLevelOutput{Levels: levelMap})
+		}
 
-		return cmds.EmitOnce(res, &MessageOutput{s})
 	},
 	Encoders: cmds.EncoderMap{
-		cmds.Text: cmds.MakeTypedEncoder(func(req *cmds.Request, w io.Writer, out *MessageOutput) error {
-			fmt.Fprint(w, out.Message)
+		cmds.Text: cmds.MakeTypedEncoder(func(req *cmds.Request, w io.Writer, out *logLevelOutput) error {
+			if out.Message != "" {
+				fmt.Fprint(w, out.Message)
+				return nil
+			}
+
+			// Check if this is an RPC call by looking for the encoding option
+			encoding, _ := req.Options["encoding"].(string)
+			isRPC := encoding == "json"
+
+			// Determine whether to show subsystem names in output.
+			// Show subsystem names when:
+			// 1. It's an RPC call (needs JSON structure with named fields)
+			// 2. Multiple subsystems are displayed (for clarity when showing many levels)
+			showNames := isRPC || len(out.Levels) > 1
+
+			levelNames := make([]string, 0, len(out.Levels))
+			for subsystem, level := range out.Levels {
+				if showNames {
+					// Show subsystem name when it's RPC or when showing multiple subsystems
+					levelNames = append(levelNames, fmt.Sprintf("%s: %s", subsystem, level))
+				} else {
+					// For CLI calls with single subsystem, only show the level
+					levelNames = append(levelNames, level)
+				}
+			}
+			slices.Sort(levelNames)
+			for _, ln := range levelNames {
+				fmt.Fprintln(w, ln)
+			}
 			return nil
 		}),
 	},
-	Type: MessageOutput{},
+	Type: logLevelOutput{},
 }
 
 var logLsCmd = &cmds.Command{
@@ -103,12 +239,10 @@ subsystems of a running daemon.
 	Type: stringList{},
 }
 
-const logLevelOption = "log-level"
-
 var logTailCmd = &cmds.Command{
 	Status: cmds.Experimental,
 	Helptext: cmds.HelpText{
-		Tagline: "Read and outpt log messages.",
+		Tagline: "Read and output log messages.",
 		ShortDescription: `
 Outputs log messages as they are generated.
 
@@ -130,7 +264,7 @@ This will only return 'info' logs from bitswap and skip 'debug'.
 		var pipeReader *logging.PipeReader
 		logLevelString, _ := req.Options[logLevelOption].(string)
 		if logLevelString != "" {
-			logLevel, err := logging.LevelFromString(logLevelString)
+			logLevel, err := logging.Parse(logLevelString)
 			if err != nil {
 				return fmt.Errorf("setting log level %s: %w", logLevelString, err)
 			}

docs/changelogs/v0.37.md

@@ -11,7 +11,8 @@ This release was brought to you by the [Shipyard](https://ipshipyard.com/) team.
 - [Overview](#overview)
 - [🔦 Highlights](#-highlights)
   - [Clear provide queue when reprovide strategy changes](#clear-provide-queue-when-reprovide-strategy-changes)
-  - [Named pins in `ipfs add` command](#-named-pins-in-ipfs-add-command)
+  - [🪵 Revamped `ipfs log level` command](#-revamped-ipfs-log-level-command)
+  - [📌 Named pins in `ipfs add` command](#-named-pins-in-ipfs-add-command)
   - [⚙️ `Reprovider.Strategy` is now consistently respected](#-reprovider-strategy-is-now-consistently-respected)
   - [Removed unnecessary dependencies](#removed-unnecessary-dependencies)
   - [Deprecated `ipfs stats reprovide`](#deprecated-ipfs-stats-reprovide)
@@ -34,6 +35,26 @@ A new `ipfs provide clear` command also allows manual queue clearing for debuggi
 > [!NOTE]
 > Upgrading to Kubo 0.37 will automatically clear any preexisting provide queue. The next time `Reprovider.Interval` hits, `Reprovider.Strategy` will be executed on a clean slate, ensuring consistent behavior with your current configuration.
 
+#### 🪵 Revamped `ipfs log level` command
+
+The `ipfs log level` command has been completely revamped to support both getting and setting log levels with a unified interface.
+
+**New: Getting log levels**
+
+- `ipfs log level` - Shows default level only
+- `ipfs log level all` - Shows log level for every subsystem, including default level
+- `ipfs log level foo` - Shows log level for a specific subsystem only
+- Kubo RPC API: `POST /api/v0/log/level?arg=<subsystem>`
+
+**Enhanced: Setting log levels**
+
+- `ipfs log level foo debug` - Sets "foo" subsystem to "debug" level
+- `ipfs log level all info` - Sets all subsystems to "info" level (convenient, no escaping)
+- `ipfs log level '*' info` - Equivalent to above but requires shell escaping
+- `ipfs log level foo default` - Sets "foo" subsystem to current default level
+
+The command now provides full visibility into your current logging configuration while maintaining full backward compatibility. Both `all` and `*` work for specifying all subsystems, with `all` being more convenient since it doesn't require shell escaping.
+
 #### 🧷 Named pins in `ipfs add` command
 
 Added `--pin-name` flag to `ipfs add` for assigning names to pins.

docs/examples/kubo-as-a-library/go.mod

@@ -90,7 +90,7 @@ require (
 	github.com/ipfs/go-ipld-format v0.6.2 // indirect
 	github.com/ipfs/go-ipld-git v0.1.1 // indirect
 	github.com/ipfs/go-ipld-legacy v0.2.2 // indirect
-	github.com/ipfs/go-log/v2 v2.6.0 // indirect
+	github.com/ipfs/go-log/v2 v2.8.0 // indirect
 	github.com/ipfs/go-metrics-interface v0.3.0 // indirect
 	github.com/ipfs/go-peertaskqueue v0.8.2 // indirect
 	github.com/ipfs/go-unixfsnode v1.10.1 // indirect

docs/examples/kubo-as-a-library/go.sum

@@ -345,8 +345,8 @@ github.com/ipfs/go-ipld-legacy v0.2.2/go.mod h1:hhkj+b3kG9b2BcUNw8IFYAsfeNo8E3U7
 github.com/ipfs/go-log v0.0.1/go.mod h1:kL1d2/hzSpI0thNYjiKfjanbVNU+IIGA/WnNESY9leM=
 github.com/ipfs/go-log v1.0.5 h1:2dOuUCB1Z7uoczMWgAyDck5JLb72zHzrMnGnCNNbvY8=
 github.com/ipfs/go-log v1.0.5/go.mod h1:j0b8ZoR+7+R99LD9jZ6+AJsrzkPbSXbZfGakb5JPtIo=
-github.com/ipfs/go-log/v2 v2.6.0 h1:2Nu1KKQQ2ayonKp4MPo6pXCjqw1ULc9iohRqWV5EYqg=
-github.com/ipfs/go-log/v2 v2.6.0/go.mod h1:p+Efr3qaY5YXpx9TX7MoLCSEZX5boSWj9wh86P5HJa8=
+github.com/ipfs/go-log/v2 v2.8.0 h1:SptNTPJQV3s5EF4FdrTu/yVdOKfGbDgn1EBZx4til2o=
+github.com/ipfs/go-log/v2 v2.8.0/go.mod h1:2LEEhdv8BGubPeSFTyzbqhCqrwqxCbuTNTLWqgNAipo=
 github.com/ipfs/go-metrics-interface v0.3.0 h1:YwG7/Cy4R94mYDUuwsBfeziJCVm9pBMJ6q/JR9V40TU=
 github.com/ipfs/go-metrics-interface v0.3.0/go.mod h1:OxxQjZDGocXVdyTPocns6cOLwHieqej/jos7H4POwoY=
 github.com/ipfs/go-peertaskqueue v0.8.2 h1:PaHFRaVFdxQk1Qo3OKiHPYjmmusQy7gKQUaL8JDszAU=

go.mod

@@ -39,7 +39,7 @@ require (
 	github.com/ipfs/go-ipld-format v0.6.2
 	github.com/ipfs/go-ipld-git v0.1.1
 	github.com/ipfs/go-ipld-legacy v0.2.2
-	github.com/ipfs/go-log/v2 v2.6.0
+	github.com/ipfs/go-log/v2 v2.8.0
 	github.com/ipfs/go-metrics-interface v0.3.0
 	github.com/ipfs/go-metrics-prometheus v0.1.0
 	github.com/ipfs/go-test v0.2.2

go.sum

@@ -414,8 +414,8 @@ github.com/ipfs/go-ipld-legacy v0.2.2/go.mod h1:hhkj+b3kG9b2BcUNw8IFYAsfeNo8E3U7
 github.com/ipfs/go-log v0.0.1/go.mod h1:kL1d2/hzSpI0thNYjiKfjanbVNU+IIGA/WnNESY9leM=
 github.com/ipfs/go-log v1.0.5 h1:2dOuUCB1Z7uoczMWgAyDck5JLb72zHzrMnGnCNNbvY8=
 github.com/ipfs/go-log v1.0.5/go.mod h1:j0b8ZoR+7+R99LD9jZ6+AJsrzkPbSXbZfGakb5JPtIo=
-github.com/ipfs/go-log/v2 v2.6.0 h1:2Nu1KKQQ2ayonKp4MPo6pXCjqw1ULc9iohRqWV5EYqg=
-github.com/ipfs/go-log/v2 v2.6.0/go.mod h1:p+Efr3qaY5YXpx9TX7MoLCSEZX5boSWj9wh86P5HJa8=
+github.com/ipfs/go-log/v2 v2.8.0 h1:SptNTPJQV3s5EF4FdrTu/yVdOKfGbDgn1EBZx4til2o=
+github.com/ipfs/go-log/v2 v2.8.0/go.mod h1:2LEEhdv8BGubPeSFTyzbqhCqrwqxCbuTNTLWqgNAipo=
 github.com/ipfs/go-metrics-interface v0.3.0 h1:YwG7/Cy4R94mYDUuwsBfeziJCVm9pBMJ6q/JR9V40TU=
 github.com/ipfs/go-metrics-interface v0.3.0/go.mod h1:OxxQjZDGocXVdyTPocns6cOLwHieqej/jos7H4POwoY=
 github.com/ipfs/go-metrics-prometheus v0.1.0 h1:bApWOHkrH3VTBHzTHrZSfq4n4weOZDzZFxUXv+HyKcA=