trimming down to ipfs watchers

pkg/client/eth_client.go

@@ -0,0 +1,63 @@
+// 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 client
+
+import (
+	"context"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/ethclient"
+)
+
+type EthClient struct {
+	client *ethclient.Client
+}
+
+func NewEthClient(client *ethclient.Client) EthClient {
+	return EthClient{client: client}
+}
+
+func (client EthClient) BlockByNumber(ctx context.Context, number *big.Int) (*types.Block, error) {
+	return client.client.BlockByNumber(ctx, number)
+}
+
+func (client EthClient) CallContract(ctx context.Context, msg ethereum.CallMsg, blockNumber *big.Int) ([]byte, error) {
+	return client.client.CallContract(ctx, msg, blockNumber)
+}
+
+func (client EthClient) FilterLogs(ctx context.Context, q ethereum.FilterQuery) ([]types.Log, error) {
+	return client.client.FilterLogs(ctx, q)
+}
+
+func (client EthClient) HeaderByNumber(ctx context.Context, number *big.Int) (*types.Header, error) {
+	return client.client.HeaderByNumber(ctx, number)
+}
+
+func (client EthClient) TransactionSender(ctx context.Context, tx *types.Transaction, block common.Hash, index uint) (common.Address, error) {
+	return client.client.TransactionSender(ctx, tx, block, index)
+}
+
+func (client EthClient) TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error) {
+	return client.client.TransactionReceipt(ctx, txHash)
+}
+
+func (client EthClient) BalanceAt(ctx context.Context, account common.Address, blockNumber *big.Int) (*big.Int, error) {
+	return client.client.BalanceAt(ctx, account, blockNumber)
+}

pkg/client/rpc_client.go

@@ -0,0 +1,93 @@
+// 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 client
+
+import (
+	"context"
+	"errors"
+	"reflect"
+
+	"github.com/ethereum/go-ethereum/rpc"
+)
+
+// RPCClient is a wrapper around the geth RPC client
+type RPCClient struct {
+	client  *rpc.Client
+	ipcPath string
+}
+
+// BatchElem is a struct to hold the elements of a BatchCall
+type BatchElem struct {
+	Method string
+	Args   []interface{}
+	Result interface{}
+	Error  error
+}
+
+// NewRPCClient creates a new RpcClient
+func NewRPCClient(client *rpc.Client, ipcPath string) RPCClient {
+	return RPCClient{
+		client:  client,
+		ipcPath: ipcPath,
+	}
+}
+
+// CallContext makes an rpc method call with the provided context and arguments
+func (client RPCClient) CallContext(ctx context.Context, result interface{}, method string, args ...interface{}) error {
+	//If an empty interface (or other nil object) is passed to CallContext, when the JSONRPC message is created the params will
+	//be interpreted as [null]. This seems to work fine for most of the ethereum clients (which presumably ignore a null parameter.
+	//Ganache however does not ignore it, and throws an 'Incorrect number of arguments' error.
+	if args == nil {
+		return client.client.CallContext(ctx, result, method)
+	}
+	return client.client.CallContext(ctx, result, method, args...)
+}
+
+func (client RPCClient) IpcPath() string {
+	return client.ipcPath
+}
+
+func (client RPCClient) SupportedModules() (map[string]string, error) {
+	return client.client.SupportedModules()
+}
+
+func (client RPCClient) BatchCall(batch []BatchElem) error {
+	var rpcBatch []rpc.BatchElem
+	for _, batchElem := range batch {
+		var newBatchElem = rpc.BatchElem{
+			Result: batchElem.Result,
+			Method: batchElem.Method,
+			Args:   batchElem.Args,
+			Error:  batchElem.Error,
+		}
+		rpcBatch = append(rpcBatch, newBatchElem)
+	}
+	return client.client.BatchCall(rpcBatch)
+}
+
+// Subscribe subscribes to an rpc "namespace_subscribe" subscription with the given channel
+// The first argument needs to be the method we wish to invoke
+func (client RPCClient) Subscribe(namespace string, payloadChan interface{}, args ...interface{}) (*rpc.ClientSubscription, error) {
+	chanVal := reflect.ValueOf(payloadChan)
+	if chanVal.Kind() != reflect.Chan || chanVal.Type().ChanDir()&reflect.SendDir == 0 {
+		return nil, errors.New("second argument to Subscribe must be a writable channel")
+	}
+	if chanVal.IsNil() {
+		return nil, errors.New("channel given to Subscribe must not be nil")
+	}
+	return client.client.Subscribe(context.Background(), namespace, payloadChan, args...)
+}