initial draft of neo4j database driver

pkg/neo4j/import-export.go

@@ -0,0 +1,97 @@
+package neo4j
+
+import (
+	"bufio"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+
+	"next.orly.dev/pkg/encoders/event"
+)
+
+// Import imports events from a reader (JSONL format)
+func (n *N) Import(rr io.Reader) {
+	n.ImportEventsFromReader(context.Background(), rr)
+}
+
+// Export exports events to a writer (JSONL format)
+func (n *N) Export(c context.Context, w io.Writer, pubkeys ...[]byte) {
+	// Query all events or events for specific pubkeys
+	// Write as JSONL
+
+	// Stub implementation
+	fmt.Fprintf(w, "# Export not yet implemented for neo4j\n")
+}
+
+// ImportEventsFromReader imports events from a reader
+func (n *N) ImportEventsFromReader(ctx context.Context, rr io.Reader) error {
+	scanner := bufio.NewScanner(rr)
+	scanner.Buffer(make([]byte, 1024*1024), 10*1024*1024) // 10MB max line size
+
+	count := 0
+	for scanner.Scan() {
+		line := scanner.Bytes()
+		if len(line) == 0 {
+			continue
+		}
+
+		// Skip comments
+		if line[0] == '#' {
+			continue
+		}
+
+		// Parse event
+		ev := &event.E{}
+		if err := json.Unmarshal(line, ev); err != nil {
+			n.Logger.Warningf("failed to parse event: %v", err)
+			continue
+		}
+
+		// Save event
+		if _, err := n.SaveEvent(ctx, ev); err != nil {
+			n.Logger.Warningf("failed to import event: %v", err)
+			continue
+		}
+
+		count++
+		if count%1000 == 0 {
+			n.Logger.Infof("imported %d events", count)
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return fmt.Errorf("scanner error: %w", err)
+	}
+
+	n.Logger.Infof("import complete: %d events", count)
+	return nil
+}
+
+// ImportEventsFromStrings imports events from JSON strings
+func (n *N) ImportEventsFromStrings(
+	ctx context.Context,
+	eventJSONs []string,
+	policyManager interface{ CheckPolicy(action string, ev *event.E, pubkey []byte, remote string) (bool, error) },
+) error {
+	for _, eventJSON := range eventJSONs {
+		ev := &event.E{}
+		if err := json.Unmarshal([]byte(eventJSON), ev); err != nil {
+			continue
+		}
+
+		// Check policy if manager is provided
+		if policyManager != nil {
+			if allowed, err := policyManager.CheckPolicy("write", ev, ev.Pubkey[:], "import"); err != nil || !allowed {
+				continue
+			}
+		}
+
+		// Save event
+		if _, err := n.SaveEvent(ctx, ev); err != nil {
+			n.Logger.Warningf("failed to import event: %v", err)
+		}
+	}
+
+	return nil
+}