swarm: localstore hasser (#19230)

2 files changed, 94 insertions, 0 deletions

diff --git a/swarm/storage/localstore/mode_has.go b/swarm/storage/localstore/mode_has.go
new file mode 100644
index 000000000..90feaceef
--- /dev/null
+++ b/swarm/storage/localstore/mode_has.go
@@ -0,0 +1,39 @@
+// Copyright 2019 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package localstore
+
+import (
+	"github.com/ethereum/go-ethereum/swarm/chunk"
+)
+
+// Hasser provides Has method to retrieve Chunks
+// from database.
+type Hasser struct {
+	db *DB
+}
+
+// NewHasser returns a new Hasser on database.
+func (db *DB) NewHasser() *Hasser {
+	return &Hasser{
+		db: db,
+	}
+}
+
+// Has returns true if the chunk is stored in database.
+func (h *Hasser) Has(addr chunk.Address) (bool, error) {
+	return h.db.retrievalDataIndex.Has(addressToItem(addr))
+}
diff --git a/swarm/storage/localstore/mode_has_test.go b/swarm/storage/localstore/mode_has_test.go
new file mode 100644
index 000000000..332616ca2
--- /dev/null
+++ b/swarm/storage/localstore/mode_has_test.go
@@ -0,0 +1,55 @@
+// Copyright 2019 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package localstore
+
+import (
+	"testing"
+)
+
+// TestHas validates that Hasser is returning true for
+// the stored chunk and false for one that is not stored.
+func TestHas(t *testing.T) {
+	db, cleanupFunc := newTestDB(t, nil)
+	defer cleanupFunc()
+
+	chunk := generateTestRandomChunk()
+
+	err := db.NewPutter(ModePutUpload).Put(chunk)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	hasser := db.NewHasser()
+
+	has, err := hasser.Has(chunk.Address())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !has {
+		t.Error("chunk not found")
+	}
+
+	missingChunk := generateTestRandomChunk()
+
+	has, err = hasser.Has(missingChunk.Address())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if has {
+		t.Error("unexpected chunk is found")
+	}
+}