feat(cli): improve ipfs dag stat output UX

core/commands/dag/dag.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"path"
 
+	"github.com/dustin/go-humanize"
 	"github.com/ipfs/kubo/core/commands/cmdenv"
 	"github.com/ipfs/kubo/core/commands/cmdutils"
 
@@ -349,7 +350,11 @@ type DagStatSummary struct {
 }
 
 func (s *DagStatSummary) String() string {
-	return fmt.Sprintf("Total Size: %d\nUnique Blocks: %d\nShared Size: %d\nRatio: %f", s.TotalSize, s.UniqueBlocks, s.SharedSize, s.Ratio)
+	return fmt.Sprintf("Total Size: %d (%s)\nUnique Blocks: %d\nShared Size: %d (%s)\nRatio: %f",
+		s.TotalSize, humanize.Bytes(s.TotalSize),
+		s.UniqueBlocks,
+		s.SharedSize, humanize.Bytes(s.SharedSize),
+		s.Ratio)
 }
 
 func (s *DagStatSummary) incrementTotalSize(size uint64) {
@@ -384,7 +389,7 @@ Note: This command skips duplicate blocks in reporting both size and the number
 		cmds.StringArg("root", true, true, "CID of a DAG root to get statistics for").EnableStdin(),
 	},
 	Options: []cmds.Option{
-		cmds.BoolOption(progressOptionName, "p", "Return progressive data while reading through the DAG").WithDefault(true),
+		cmds.BoolOption(progressOptionName, "p", "Show progress on stderr. Auto-detected if stderr is a terminal."),
 	},
 	Run:  dagStat,
 	Type: DagStatSummary{},

core/commands/dag/stat.go

@@ -5,6 +5,7 @@ import (
 	"io"
 	"os"
 
+	"github.com/dustin/go-humanize"
 	mdag "github.com/ipfs/boxo/ipld/merkledag"
 	"github.com/ipfs/boxo/ipld/merkledag/traverse"
 	cid "github.com/ipfs/go-cid"
@@ -19,7 +20,11 @@ import (
 // to compute the new state
 
 func dagStat(req *cmds.Request, res cmds.ResponseEmitter, env cmds.Environment) error {
-	progressive := req.Options[progressOptionName].(bool)
+	// Default to true (emit intermediate states) for HTTP/RPC clients that want progress
+	progressive := true
+	if val, specified := req.Options[progressOptionName].(bool); specified {
+		progressive = val
+	}
 	api, err := cmdenv.GetApi(env, req)
 	if err != nil {
 		return err
@@ -84,6 +89,18 @@ func dagStat(req *cmds.Request, res cmds.ResponseEmitter, env cmds.Environment)
 }
 
 func finishCLIStat(res cmds.Response, re cmds.ResponseEmitter) error {
+	// Determine whether to show progress based on TTY detection or explicit flag
+	var showProgress bool
+	val, specified := res.Request().Options[progressOptionName]
+	if !specified {
+		// Auto-detect: show progress only if stderr is a TTY
+		if errStat, err := os.Stderr.Stat(); err == nil {
+			showProgress = (errStat.Mode() & os.ModeCharDevice) != 0
+		}
+	} else {
+		showProgress = val.(bool)
+	}
+
 	var dagStats *DagStatSummary
 	for {
 		v, err := res.Next()
@@ -96,17 +113,26 @@ func finishCLIStat(res cmds.Response, re cmds.ResponseEmitter) error {
 		switch out := v.(type) {
 		case *DagStatSummary:
 			dagStats = out
-			if dagStats.Ratio == 0 {
-				length := len(dagStats.DagStatsArray)
-				if length > 0 {
-					currentStat := dagStats.DagStatsArray[length-1]
-					fmt.Fprintf(os.Stderr, "CID: %s, Size: %d, NumBlocks: %d\n", currentStat.Cid, currentStat.Size, currentStat.NumBlocks)
+			// Ratio == 0 means this is a progress update (not final result)
+			if showProgress && dagStats.Ratio == 0 {
+				// Sum up total progress across all DAGs being scanned
+				var totalBlocks int64
+				var totalSize uint64
+				for _, stat := range dagStats.DagStatsArray {
+					totalBlocks += stat.NumBlocks
+					totalSize += stat.Size
 				}
+				fmt.Fprintf(os.Stderr, "Fetched/Processed %d blocks, %d bytes (%s)\r", totalBlocks, totalSize, humanize.Bytes(totalSize))
 			}
 		default:
 			return e.TypeErr(out, v)
-
 		}
 	}
+
+	// Clear the progress line before final output
+	if showProgress {
+		fmt.Fprint(os.Stderr, "\033[2K\r")
+	}
+
 	return re.Emit(dagStats)
 }

docs/changelogs/v0.40.md

@@ -11,7 +11,8 @@ This release was brought to you by the [Shipyard](https://ipshipyard.com/) team.
 - [Overview](#overview)
 - [🔦 Highlights](#-highlights)
   - [Routing V1 HTTP API now exposed by default](#routing-v1-http-api-now-exposed-by-default)
-  - [Track total size when adding pins](#track-total-size-when-adding-pins]
+  - [Track total size when adding pins](#track-total-size-when-adding-pins)
+  - [Improved `ipfs dag stat` output](#improved-ipfs-dag-stat-output)
 - [📝 Changelog](#-changelog)
 - [👨‍👩‍👧‍👦 Contributors](#-contributors)
 
@@ -32,6 +33,30 @@ Example output:
 Fetched/Processed 336 nodes (83 MB)
 ```
 
+#### Improved `ipfs dag stat` output
+
+The `ipfs dag stat` command has been improved for better terminal UX:
+
+- Progress output now uses a single line with carriage return, avoiding terminal flooding
+- Progress is auto-detected: shown only in interactive terminals by default
+- Human-readable sizes are now displayed alongside raw byte counts
+
+Example progress (interactive terminal):
+```
+Fetched/Processed 84 blocks, 2097152 bytes (2.1 MB)
+```
+
+Example summary output:
+```
+Summary
+Total Size: 2097152 (2.1 MB)
+Unique Blocks: 42
+Shared Size: 1048576 (1.0 MB)
+Ratio: 1.500000
+```
+
+Use `--progress=true` to force progress even when piped, or `--progress=false` to disable it.
+
 ### 📝 Changelog
 
 ### 👨‍👩‍👧‍👦 Contributors