syncer - interface for syncing with a statediff subscription

pkg/ipfs/syncer.go

@@ -0,0 +1,44 @@
+// VulcanizeDB
+// Copyright © 2019 Vulcanize
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program 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 Affero General Public License for more details.
+
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package ipfs
+
+import (
+	"github.com/ethereum/go-ethereum/rpc"
+	"github.com/ethereum/go-ethereum/statediff"
+
+	"github.com/vulcanize/vulcanizedb/pkg/core"
+)
+
+type Syncer interface {
+	Sync(payloadChan chan statediff.Payload) (*rpc.ClientSubscription, error)
+}
+
+type StateDiffSyncer struct {
+	Client      core.RpcClient
+	PayloadChan chan statediff.Payload
+}
+
+func NewStateDiffSyncer(client core.RpcClient) *StateDiffSyncer {
+	return &StateDiffSyncer{
+		Client: client,
+	}
+}
+
+// Sync is the main loop for subscribing to data from the Geth state diff process
+func (i *StateDiffSyncer) Sync(payloadChan chan statediff.Payload) (*rpc.ClientSubscription, error) {
+	return i.Client.Subscribe("statediff", i.PayloadChan)
+}