rpc: implement getrawmempool RPC

closes #175

docs/rpc.md

@@ -48,7 +48,7 @@ which would yield the response:
 | `getnep5balances` | No (#498) |
 | `getnep5transfers` | No (#498) |
 | `getpeers` | Yes |
-| `getrawmempool` | No (#175) |
+| `getrawmempool` | Yes |
 | `getrawtransaction` | Yes |
 | `getstorage` | Yes |
 | `gettxout` | Yes |

pkg/rpc/server/prometheus.go

@@ -83,6 +83,14 @@ var (
 		},
 	)
 
+	getrawmempoolCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getrawmempool rpc endpoint",
+			Name:      "getrawmempool_called",
+			Namespace: "neogo",
+		},
+	)
+
 	validateaddressCalled = prometheus.NewCounter(
 		prometheus.CounterOpts{
 			Help:      "Number of calls to validateaddress rpc endpoint",
@@ -160,6 +168,7 @@ func init() {
 		getcontractstateCalled,
 		getversionCalled,
 		getpeersCalled,
+		getrawmempoolCalled,
 		validateaddressCalled,
 		getassetstateCalled,
 		getaccountstateCalled,

pkg/rpc/server/server.go

@@ -210,6 +210,15 @@ Methods:
 		peers.AddBad(s.coreServer.BadPeers())
 		results = peers
 
+	case "getrawmempool":
+		getrawmempoolCalled.Inc()
+		mp := s.chain.GetMemPool()
+		hashList := make([]util.Uint256, 0)
+		for _, item := range mp.GetVerifiedTransactions() {
+			hashList = append(hashList, item.Tx.Hash())
+		}
+		results = hashList
+
 	case "getstorage":
 		getstorageCalled.Inc()
 		results, resultsErr = s.getStorage(reqParams)

pkg/rpc/server/server_helper_test.go

@@ -9,9 +9,11 @@ import (
 	"github.com/CityOfZion/neo-go/pkg/core"
 	"github.com/CityOfZion/neo-go/pkg/core/block"
 	"github.com/CityOfZion/neo-go/pkg/core/storage"
+	"github.com/CityOfZion/neo-go/pkg/core/transaction"
 	"github.com/CityOfZion/neo-go/pkg/io"
 	"github.com/CityOfZion/neo-go/pkg/network"
 	"github.com/CityOfZion/neo-go/pkg/rpc/request"
+	"github.com/CityOfZion/neo-go/pkg/util"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/zap/zaptest"
 )
@@ -66,3 +68,21 @@ func initServerWithInMemoryChain(t *testing.T) (*core.Blockchain, http.HandlerFu
 
 	return chain, handler
 }
+
+type FeerStub struct{}
+
+func (fs *FeerStub) NetworkFee(*transaction.Transaction) util.Fixed8 {
+	return 0
+}
+
+func (fs *FeerStub) IsLowPriority(util.Fixed8) bool {
+	return false
+}
+
+func (fs *FeerStub) FeePerByte(*transaction.Transaction) util.Fixed8 {
+	return 0
+}
+
+func (fs *FeerStub) SystemFee(*transaction.Transaction) util.Fixed8 {
+	return 0
+}

pkg/rpc/server/server_test.go

@@ -14,6 +14,7 @@ import (
 
 	"github.com/CityOfZion/neo-go/pkg/core"
 	"github.com/CityOfZion/neo-go/pkg/core/transaction"
+	"github.com/CityOfZion/neo-go/pkg/internal/random"
 	"github.com/CityOfZion/neo-go/pkg/rpc/response"
 	"github.com/CityOfZion/neo-go/pkg/rpc/response/result"
 	"github.com/CityOfZion/neo-go/pkg/util"
@@ -664,6 +665,35 @@ func TestRPC(t *testing.T) {
 		assert.Equal(t, util.Fixed8FromInt64(100000000), txOut.Value)
 		assert.Equal(t, "AZ81H31DMWzbSnFDLFkzh9vHwaDLayV7fU", txOut.Address)
 	})
+
+	t.Run("getrawmempool", func(t *testing.T) {
+		mp := chain.GetMemPool()
+		// `expected` stores hashes of previously added txs
+		expected := make([]util.Uint256, 0)
+		for _, tx := range mp.GetVerifiedTransactions() {
+			expected = append(expected, tx.Tx.Hash())
+		}
+		for i := 0; i < 5; i++ {
+			tx := &transaction.Transaction{
+				Type: transaction.MinerType,
+				Data: &transaction.MinerTX{
+					Nonce: uint32(random.Int(0, 1000000000)),
+				},
+			}
+			assert.NoError(t, mp.Add(tx, &FeerStub{}))
+			expected = append(expected, tx.Hash())
+		}
+
+		rpc := `{"jsonrpc": "2.0", "id": 1, "method": "getrawmempool", "params": []}`
+		body := doRPCCall(rpc, handler, t)
+		res := checkErrGetResult(t, body, false)
+
+		var actual []util.Uint256
+		err := json.Unmarshal(res, &actual)
+		require.NoErrorf(t, err, "could not parse response: %s", res)
+
+		assert.ElementsMatch(t, expected, actual)
+	})
 }
 
 func (tc rpcTestCase) getResultPair(e *executor) (expected interface{}, res interface{}) {