From ad808603687eeaefaea6487246efdd352cf6f3c1 Mon Sep 17 00:00:00 2001
From: Djeeberjr <djeeberjr@gmail.com>
Date: Sat, 7 Aug 2021 01:42:47 +0200
Subject: [PATCH] cache invalidation for mutations

---
 internal/mutations.go | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/internal/mutations.go b/internal/mutations.go
index 4c74b7d..1216fae 100644
--- a/internal/mutations.go
+++ b/internal/mutations.go
@@ -3,7 +3,9 @@ package s3browser
 import (
 	"context"
 	"fmt"
+	"path/filepath"
 
+	"github.com/graph-gophers/dataloader"
 	"github.com/minio/minio-go/v7"
 )
 
@@ -16,7 +18,23 @@ func deleteMutation(ctx context.Context, id string) error {
 
 	// TODO: it is posible to remove multiple objects with a single call.
 	// Is it better to batch this?
-	return s3Client.RemoveObject(ctx, bucketName, id, minio.RemoveObjectOptions{})
+	err := s3Client.RemoveObject(ctx, bucketName, id, minio.RemoveObjectOptions{})
+
+	if err != nil {
+		return err
+	}
+
+	// Invalidate cache
+	loader, ok := ctx.Value("loader").(map[string]*dataloader.Loader)
+	if !ok {
+		return fmt.Errorf("Failed to get loader from context")
+	}
+
+	loader["getFile"].Clear(ctx, dataloader.StringKey(id))
+	loader["listObjects"].Clear(ctx, dataloader.StringKey(id))
+	loader["getFiles"].Clear(ctx, dataloader.StringKey(filepath.Dir(id)))
+
+	return nil
 }
 
 func copyMutation(ctx context.Context, src, dest string) (*File, error) {
@@ -38,6 +56,18 @@ func copyMutation(ctx context.Context, src, dest string) (*File, error) {
 		return nil, err
 	}
 
+	// Invalidate cache
+
+	loader, ok := ctx.Value("loader").(map[string]*dataloader.Loader)
+
+	// TODO: Do we want to error when the operation
+	// has succeeded but the cache invalidation has failed ?
+	if ok {
+		loader["getFile"].Clear(ctx, dataloader.StringKey(info.Key))
+		loader["listObjects"].Clear(ctx, dataloader.StringKey(info.Key))
+		loader["getFiles"].Clear(ctx, dataloader.StringKey(filepath.Dir(info.Key)))
+	}
+
 	return &File{
 		ID: info.Key,
 	}, nil