upd parser

Author: evgeniy-scherbina

fixtures/bedrock/parse_eventstream.go

@@ -1,10 +1,16 @@
 //go:build ignore
 
-// Usage: go run parse_eventstream.go <file.resp.bin>
+// Usage:
 //
-// Decodes an AWS EventStream binary file and prints each frame's
-// decoded JSON body. Use this to inspect captured Bedrock responses
-// and verify fixture contents.
+//	go run parse_eventstream.go [dir]
+//
+// Finds all .resp.bin files in dir (default: current directory) and
+// generates a corresponding .resp.decoded file for each one. Existing
+// .resp.decoded files are overwritten.
+//
+// To decode a single file:
+//
+//	go run parse_eventstream.go path/to/file.resp.bin
 package main
 
 import (
@@ -13,23 +19,64 @@ import (
 	"encoding/json"
 	"fmt"
 	"os"
+	"path/filepath"
+	"strings"
 
 	"github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream"
 	"github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream/eventstreamapi"
 )
 
 func main() {
-	if len(os.Args) < 2 {
-		fmt.Fprintf(os.Stderr, "usage: go run parse_eventstream.go <file.resp.bin>\n")
+	arg := "."
+	if len(os.Args) > 1 {
+		arg = os.Args[1]
+	}
+
+	info, err := os.Stat(arg)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "stat %s: %v\n", arg, err)
 		os.Exit(1)
 	}
 
-	data, err := os.ReadFile(os.Args[1])
+	if !info.IsDir() {
+		if err := decodeFile(arg, os.Stdout); err != nil {
+			fmt.Fprintf(os.Stderr, "%v\n", err)
+			os.Exit(1)
+		}
+		return
+	}
+
+	files, err := filepath.Glob(filepath.Join(arg, "*.resp.bin"))
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "read file: %v\n", err)
+		fmt.Fprintf(os.Stderr, "glob: %v\n", err)
+		os.Exit(1)
+	}
+	if len(files) == 0 {
+		fmt.Fprintf(os.Stderr, "no .resp.bin files found in %s\n", arg)
 		os.Exit(1)
 	}
 
+	for _, binFile := range files {
+		outFile := strings.TrimSuffix(binFile, ".resp.bin") + ".resp.decoded"
+		f, err := os.Create(outFile)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "create %s: %v\n", outFile, err)
+			continue
+		}
+		if err := decodeFile(binFile, f); err != nil {
+			fmt.Fprintf(os.Stderr, "decode %s: %v\n", binFile, err)
+		}
+		f.Close()
+		fmt.Printf("%s -> %s\n", filepath.Base(binFile), filepath.Base(outFile))
+	}
+}
+
+func decodeFile(path string, w *os.File) error {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return fmt.Errorf("read %s: %w", path, err)
+	}
+
 	decoder := eventstream.NewDecoder()
 	reader := bytes.NewReader(data)
 	frameNum := 0
@@ -44,40 +91,41 @@ func main() {
 		messageType := msg.Headers.Get(eventstreamapi.MessageTypeHeader)
 		eventType := msg.Headers.Get(eventstreamapi.EventTypeHeader)
 
-		fmt.Printf("=== Frame %d ===\n", frameNum)
-		fmt.Printf("  message-type: %s\n", headerStr(messageType))
-		fmt.Printf("  event-type:   %s\n", headerStr(eventType))
+		fmt.Fprintf(w, "=== Frame %d ===\n", frameNum)
+		fmt.Fprintf(w, "  message-type: %s\n", headerStr(messageType))
+		fmt.Fprintf(w, "  event-type:   %s\n", headerStr(eventType))
 
 		if headerStr(eventType) != "chunk" {
-			fmt.Printf("  payload: %s\n\n", string(msg.Payload))
+			fmt.Fprintf(w, "  payload: %s\n\n", string(msg.Payload))
 			continue
 		}
 
 		var chunk struct {
 			Bytes string `json:"bytes"`
 		}
 		if err := json.Unmarshal(msg.Payload, &chunk); err != nil {
-			fmt.Printf("  unmarshal error: %v\n\n", err)
+			fmt.Fprintf(w, "  unmarshal error: %v\n\n", err)
 			continue
 		}
 
 		decoded, err := base64.StdEncoding.DecodeString(chunk.Bytes)
 		if err != nil {
-			fmt.Printf("  base64 decode error: %v\n\n", err)
+			fmt.Fprintf(w, "  base64 decode error: %v\n\n", err)
 			continue
 		}
 
 		var pretty json.RawMessage
 		if err := json.Unmarshal(decoded, &pretty); err != nil {
-			fmt.Printf("  json: %s\n\n", string(decoded))
+			fmt.Fprintf(w, "  json: %s\n\n", string(decoded))
 			continue
 		}
 
 		indented, _ := json.MarshalIndent(pretty, "  ", "  ")
-		fmt.Printf("  body:\n  %s\n\n", string(indented))
+		fmt.Fprintf(w, "  body:\n  %s\n\n", string(indented))
 	}
 
-	fmt.Printf("Total frames: %d\n", frameNum)
+	fmt.Fprintf(w, "Total frames: %d\n", frameNum)
+	return nil
 }
 
 func headerStr(h eventstream.Value) string {