rpc: implement getunclaimed

closes #712

docs/rpc.md

@@ -30,41 +30,40 @@ which would yield the response:
     }
 }
 ```
-
 ### Supported methods
 
-| Method  | Implemented |
-| ------- | ------------|
-| `getaccountstate` | Yes |
-| `getapplicationlog` | Yes |
-| `getassetstate` | Yes |
-| `getbestblockhash` | Yes |
-| `getblock` | Yes |
-| `getblockcount` | Yes |
-| `getblockhash` | Yes |
-| `getblockheader` | Yes |
-| `getblocksysfee` | Yes |
-| `getclaimable` | Yes |
-| `getconnectioncount` | Yes |
-| `getcontractstate` | Yes |
-| `getnep5balances` | Yes |
-| `getnep5transfers` | Yes |
-| `getpeers` | Yes |
-| `getrawmempool` | Yes |
-| `getrawtransaction` | Yes |
-| `getstorage` | Yes |
-| `gettransactionheight` | Yes |
-| `gettxout` | Yes |
-| `getunclaimed` | No (#712) |
-| `getunspents` | Yes |
-| `getvalidators` | Yes |
-| `getversion` | Yes |
-| `invoke` | Yes |
-| `invokefunction` | Yes |
-| `invokescript` | Yes |
-| `sendrawtransaction` | Yes |
-| `submitblock` | Yes |
-| `validateaddress` | Yes |
+| Method  |
+| ------- |
+| `getaccountstate` |
+| `getapplicationlog` |
+| `getassetstate` |
+| `getbestblockhash` |
+| `getblock` |
+| `getblockcount` |
+| `getblockhash` |
+| `getblockheader` |
+| `getblocksysfee` |
+| `getclaimable` |
+| `getconnectioncount` |
+| `getcontractstate` |
+| `getnep5balances` |
+| `getnep5transfers` |
+| `getpeers` |
+| `getrawmempool` |
+| `getrawtransaction` |
+| `getstorage` |
+| `gettransactionheight` |
+| `gettxout` |
+| `getunclaimed` |
+| `getunspents` |
+| `getvalidators` |
+| `getversion` |
+| `invoke` |
+| `invokefunction` |
+| `invokescript` |
+| `sendrawtransaction` |
+| `submitblock` |
+| `validateaddress` |
 
 ### Unsupported methods
 

pkg/rpc/response/result/unclaimed.go

@@ -0,0 +1,49 @@
+package result
+
+import (
+	"github.com/nspcc-dev/neo-go/pkg/core"
+	"github.com/nspcc-dev/neo-go/pkg/core/state"
+	"github.com/nspcc-dev/neo-go/pkg/util"
+)
+
+// Unclaimed wrapper is used to represent getunclaimed return result.
+type Unclaimed struct {
+	Available   util.Fixed8 `json:"available"`
+	Unavailable util.Fixed8 `json:"unavailable"`
+	Unclaimed   util.Fixed8 `json:"unclaimed"`
+}
+
+// NewUnclaimed creates a new Unclaimed wrapper using given Blockchainer.
+func NewUnclaimed(a *state.Account, chain core.Blockchainer) (*Unclaimed, error) {
+	var (
+		available   util.Fixed8
+		unavailable util.Fixed8
+	)
+
+	for _, ucb := range a.Unclaimed {
+		gen, sys, err := chain.CalculateClaimable(ucb.Value, ucb.Start, ucb.End)
+		if err != nil {
+			return nil, err
+		}
+		available += gen + sys
+	}
+
+	blockHeight := chain.BlockHeight()
+	for _, usb := range a.Balances[core.GoverningTokenID()] {
+		_, txHeight, err := chain.GetTransaction(usb.Tx)
+		if err != nil {
+			return nil, err
+		}
+		gen, sys, err := chain.CalculateClaimable(usb.Value, txHeight, blockHeight)
+		if err != nil {
+			return nil, err
+		}
+		unavailable += gen + sys
+	}
+
+	return &Unclaimed{
+		Available:   available,
+		Unavailable: unavailable,
+		Unclaimed:   available + unavailable,
+	}, nil
+}

pkg/rpc/server/prometheus.go

@@ -178,6 +178,14 @@ var (
 		},
 	)
 
+	getunclaimedCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getunclaimed rpc endpoint",
+			Name:      "getunclaimed_called",
+			Namespace: "neogo",
+		},
+	)
+
 	getunspentsCalled = prometheus.NewCounter(
 		prometheus.CounterOpts{
 			Help:      "Number of calls to getunspents rpc endpoint",
@@ -229,6 +237,7 @@ func init() {
 		validateaddressCalled,
 		getassetstateCalled,
 		getaccountstateCalled,
+		getunclaimedCalled,
 		getunspentsCalled,
 		gettransactionheightCalled,
 		gettxoutCalled,

pkg/rpc/server/server.go

@@ -298,6 +298,10 @@ Methods:
 		gettxoutCalled.Inc()
 		results, resultsErr = s.getTxOut(reqParams)
 
+	case "getunclaimed":
+		getunclaimedCalled.Inc()
+		results, resultsErr = s.getUnclaimed(reqParams)
+
 	case "getunspents":
 		getunspentsCalled.Inc()
 		results, resultsErr = s.getAccountState(reqParams, true)
@@ -768,6 +772,25 @@ func (s *Server) getBlockHeader(reqParams request.Params) (interface{}, error) {
 	return hex.EncodeToString(buf.Bytes()), nil
 }
 
+// getUnclaimed returns unclaimed GAS amount of the specified address.
+func (s *Server) getUnclaimed(ps request.Params) (interface{}, error) {
+	p, ok := ps.ValueWithType(0, request.StringT)
+	if !ok {
+		return nil, response.ErrInvalidParams
+	}
+	u, err := p.GetUint160FromAddress()
+	if err != nil {
+		return nil, response.ErrInvalidParams
+	}
+
+	acc := s.chain.GetAccountState(u)
+	if acc == nil {
+		return nil, response.NewInternalServerError("unknown account", nil)
+	}
+
+	return result.NewUnclaimed(acc, s.chain)
+}
+
 // getValidators returns the current NEO consensus nodes information and voting status.
 func (s *Server) getValidators() (interface{}, error) {
 	var validators keys.PublicKeys

pkg/rpc/server/server_test.go

@@ -601,6 +601,32 @@ var rpcTestCases = map[string][]rpcTestCase{
 			fail:   true,
 		},
 	},
+	"getunclaimed": {
+		{
+			name:   "no params",
+			params: "[]",
+			fail:   true,
+		},
+		{
+			name:   "invalid address",
+			params: `["invalid"]`,
+			fail:   true,
+		},
+		{
+			name:   "positive",
+			params: `["AZ81H31DMWzbSnFDLFkzh9vHwaDLayV7fU"]`,
+			result: func(*executor) interface{} {
+				return &result.Unclaimed{}
+			},
+			check: func(t *testing.T, e *executor, uncl interface{}) {
+				res, ok := uncl.(*result.Unclaimed)
+				require.True(t, ok)
+				assert.Equal(t, res.Available, util.Fixed8FromInt64(8))
+				assert.True(t, res.Unavailable > 0)
+				assert.Equal(t, res.Available + res.Unavailable, res.Unclaimed)
+			},
+		},
+	},
 	"getunspents": {
 		{
 			name:   "positive",