feat(op-program-svc): add info.json to identify prestates

kurtosis-devnet/op-program-svc/Dockerfile

@@ -1,4 +1,4 @@
-ARG BASE_VERSION=latest
+ARG BASE_IMAGE=op-program-base:latest
 
 FROM golang:1.22.7-alpine3.20 AS builder
 
@@ -9,7 +9,7 @@ RUN go mod init op-program-svc
 RUN go build -o op-program-svc .
 
 
-FROM op-program-base:${BASE_VERSION} AS svc
+FROM ${BASE_IMAGE} AS svc
 
 ARG GIT_COMMIT
 ARG GIT_DATE

kurtosis-devnet/op-program-svc/fs.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -29,6 +30,53 @@ type proofFile struct {
 	file File
 }
 
+// infoFile implements http.File for the virtual info.json file
+type infoFile struct {
+	*bytes.Reader
+	content []byte
+}
+
+func newInfoFile(proofFiles map[string]string) *infoFile {
+	// Create inverted map
+	invertedMap := make(map[string]string)
+	for hash, variablePart := range proofFiles {
+		// Replace dashes with underscores in the key
+		key := fmt.Sprintf("prestate%s", variablePart)
+		key = strings.ReplaceAll(key, "-", "_")
+		invertedMap[key] = hash
+	}
+
+	// Convert to JSON
+	content, err := json.MarshalIndent(invertedMap, "", "  ")
+	if err != nil {
+		// Fallback to empty JSON object if marshaling fails
+		content = []byte("{}")
+	}
+
+	return &infoFile{
+		Reader:  bytes.NewReader(content),
+		content: content,
+	}
+}
+
+func (f *infoFile) Close() error {
+	return nil
+}
+
+func (f *infoFile) Readdir(count int) ([]fs.FileInfo, error) {
+	return nil, fmt.Errorf("not a directory")
+}
+
+func (f *infoFile) Stat() (fs.FileInfo, error) {
+	return virtualFileInfo{
+		name:    "info.json",
+		size:    int64(len(f.content)),
+		mode:    0644,
+		modTime: time.Now(),
+		isDir:   false,
+	}, nil
+}
+
 func (f *proofFile) Close() error {
 	return f.file.Close()
 }
@@ -73,7 +121,7 @@ func (d *proofDir) Readdir(count int) ([]fs.FileInfo, error) {
 	defer d.proofMutex.RUnlock()
 
 	// If we've already read all entries
-	if d.pos >= len(d.proofFiles)*2 {
+	if d.pos >= len(d.proofFiles)*2+1 {
 		if count <= 0 {
 			return nil, nil
 		}
@@ -89,11 +137,23 @@ func (d *proofDir) Readdir(count int) ([]fs.FileInfo, error) {
 
 	start := d.pos
 	end := start + count
-	if count <= 0 || end > len(d.proofFiles)*2 {
-		end = len(d.proofFiles) * 2
+	if count <= 0 || end > len(d.proofFiles)*2+1 {
+		end = len(d.proofFiles)*2 + 1
 	}
 
 	for i := start; i < end; i++ {
+		// Special case for info.json (last entry)
+		if i == len(d.proofFiles)*2 {
+			entries = append(entries, virtualFileInfo{
+				name:    "info.json",
+				size:    0, // Size will be determined when actually opening the file
+				mode:    0644,
+				modTime: time.Now(),
+				isDir:   false,
+			})
+			continue
+		}
+
 		hash := hashes[i/2]
 		isJSON := i%2 == 0
 
@@ -167,6 +227,13 @@ func (fs *proofFileSystem) Open(name string) (http.File, error) {
 	// Clean the path and remove leading slash
 	name = strings.TrimPrefix(filepath.Clean(name), "/")
 
+	// Special case for info.json
+	if name == "info.json" {
+		fs.proofMutex.RLock()
+		defer fs.proofMutex.RUnlock()
+		return newInfoFile(fs.proofFiles), nil
+	}
+
 	fs.proofMutex.RLock()
 	defer fs.proofMutex.RUnlock()
 

kurtosis-devnet/op-program-svc/fs_test.go

@@ -78,6 +78,33 @@ func TestProofFileSystem(t *testing.T) {
 		}
 	})
 
+	t.Run("OpenInfoJSONFile", func(t *testing.T) {
+		file, err := pfs.Open("/info.json")
+		if err != nil {
+			t.Errorf("Failed to open info.json file: %v", err)
+		}
+		defer file.Close()
+
+		// Read contents
+		contents, err := io.ReadAll(file)
+		if err != nil {
+			t.Errorf("Failed to read file contents: %v", err)
+		}
+
+		// Verify the contents contain the inverted map
+		var infoData map[string]string
+		err = json.Unmarshal(contents, &infoData)
+		if err != nil {
+			t.Errorf("Failed to parse info.json contents: %v", err)
+		}
+
+		// Check that the key has dashes replaced with underscores
+		expectedKey := "prestate_test"
+		if hash, ok := infoData[expectedKey]; !ok || hash != "hash123" {
+			t.Errorf("Expected info.json to contain mapping from %s to hash123, got %v", expectedKey, hash)
+		}
+	})
+
 	t.Run("OpenNonExistentFile", func(t *testing.T) {
 		_, err := pfs.Open("/nonexistent.json")
 		if err == nil {
@@ -97,8 +124,21 @@ func TestProofFileSystem(t *testing.T) {
 			t.Errorf("Failed to read directory: %v", err)
 		}
 
-		if len(files) != 2 { // We expect both .json and .bin.gz files
-			t.Errorf("Expected 2 files, got %d", len(files))
+		// We expect both .json and .bin.gz files for hash123, plus info.json
+		if len(files) != 3 {
+			t.Errorf("Expected 3 files, got %d", len(files))
+		}
+
+		// Verify info.json is included in the directory listing
+		foundInfoJson := false
+		for _, file := range files {
+			if file.Name() == "info.json" {
+				foundInfoJson = true
+				break
+			}
+		}
+		if !foundInfoJson {
+			t.Error("info.json not found in directory listing")
 		}
 	})
 }

kurtosis-devnet/op-program-svc/main.go

@@ -21,9 +21,18 @@ func main() {
 
 	srv := createServer()
 
+	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		switch r.Method {
+		case http.MethodGet:
+			http.FileServer(srv.proofFS).ServeHTTP(w, r)
+		case http.MethodPost:
+			srv.handleUpload(w, r)
+		default:
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		}
+	})
 	// Set up routes
-	http.HandleFunc("/", srv.handleUpload)
-	http.Handle("/proofs/", http.StripPrefix("/proofs/", http.FileServer(srv.proofFS)))
+	http.HandleFunc("/", handler)
 
 	log.Printf("Starting server on :%d with:", srv.port)
 	log.Printf("  app-root: %s", srv.appRoot)