Merge pull request #675 from nspcc-dev/feature/getContractState

rpc: implement getcontractstate RPC

Closes #342.

docs/rpc.md

@@ -44,7 +44,7 @@ which would yield the response:
 | `getblockhash` | Yes |
 | `getblocksysfee` | No (#341) |
 | `getconnectioncount` | Yes |
-| `getcontractstate` | No (#342) |
+| `getcontractstate` | Yes |
 | `getnep5balances` | No (#498) |
 | `getnep5transfers` | No (#498) |
 | `getpeers` | Yes |
@@ -76,4 +76,4 @@ Both methods also don't currently support arrays in function parameters.
 ## Reference
 
 * [JSON-RPC 2.0 Specification](http://www.jsonrpc.org/specification)
-* [NEO JSON-RPC 2.0 docs](https://docs.neo.org/en-us/node/cli/apigen.html)
+* [NEO JSON-RPC 2.0 docs](https://docs.neo.org/docs/en-us/reference/rpc/latest-version/api.html)

pkg/core/helper_test.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
+	"os"
 	"testing"
 	"time"
 
@@ -17,6 +18,7 @@ import (
 	"github.com/CityOfZion/neo-go/pkg/io"
 	"github.com/CityOfZion/neo-go/pkg/smartcontract"
 	"github.com/CityOfZion/neo-go/pkg/util"
+	"github.com/CityOfZion/neo-go/pkg/vm/emit"
 	"github.com/CityOfZion/neo-go/pkg/vm/opcode"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/zap/zaptest"
@@ -163,3 +165,78 @@ func newDumbBlock() *block.Block {
 		},
 	}
 }
+
+// This function generates "../rpc/testdata/testblocks.acc" file which contains data
+// for RPC unit tests.
+// To generate new "../rpc/testdata/testblocks.acc", follow the steps:
+// 		1. Rename the function
+// 		2. Add specific test-case into "neo-go/pkg/core/blockchain_test.go"
+// 		3. Run tests with `$ make test`
+func _(t *testing.T) {
+	bc := newTestChain(t)
+	n := 50
+	blocks := makeBlocks(n)
+
+	for i := 0; i < len(blocks); i++ {
+		if err := bc.AddBlock(blocks[i]); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	tx1 := newMinerTX()
+
+	avm, err := ioutil.ReadFile("../rpc/testdata/test_contract.avm")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var props smartcontract.PropertyState
+	script := io.NewBufBinWriter()
+	emit.Bytes(script.BinWriter, []byte("Da contract dat hallos u"))
+	emit.Bytes(script.BinWriter, []byte("joe@example.com"))
+	emit.Bytes(script.BinWriter, []byte("Random Guy"))
+	emit.Bytes(script.BinWriter, []byte("0.99"))
+	emit.Bytes(script.BinWriter, []byte("Helloer"))
+	props |= smartcontract.HasStorage
+	emit.Int(script.BinWriter, int64(props))
+	emit.Int(script.BinWriter, int64(5))
+	params := make([]byte, 1)
+	params[0] = byte(7)
+	emit.Bytes(script.BinWriter, params)
+	emit.Bytes(script.BinWriter, avm)
+	emit.Syscall(script.BinWriter, "Neo.Contract.Create")
+	txScript := script.Bytes()
+
+	tx2 := transaction.NewInvocationTX(txScript, util.Fixed8FromFloat(100))
+
+	block := newBlock(uint32(n+1), tx1, tx2)
+	if err := bc.AddBlock(block); err != nil {
+		t.Fatal(err)
+	}
+
+	outStream, err := os.Create("../rpc/testdata/testblocks.acc")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer outStream.Close()
+
+	writer := io.NewBinWriterFromIO(outStream)
+
+	count := bc.BlockHeight() + 1
+	writer.WriteU32LE(count - 1)
+
+	for i := 1; i < int(count); i++ {
+		bh := bc.GetHeaderHash(i)
+		b, err := bc.GetBlock(bh)
+		if err != nil {
+			t.Fatal(err)
+		}
+		buf := io.NewBufBinWriter()
+		b.EncodeBinary(buf.BinWriter)
+		bytes := buf.Bytes()
+		writer.WriteBytes(bytes)
+		if writer.Err != nil {
+			t.Fatal(err)
+		}
+	}
+}

pkg/rpc/errors.go

@@ -62,6 +62,12 @@ func NewInternalServerError(data string, cause error) *Error {
 	return newError(-32603, http.StatusInternalServerError, "Internal error", data, cause)
 }
 
+// NewRPCError creates a new error with
+// code -100
+func NewRPCError(message string, data string, cause error) *Error {
+	return newError(-100, http.StatusUnprocessableEntity, message, data, cause)
+}
+
 // Error implements the error interface.
 func (e Error) Error() string {
 	return fmt.Sprintf("%s (%d) - %s - %s", e.Message, e.Code, e.Data, e.Cause)

pkg/rpc/prometheus.go

@@ -44,6 +44,14 @@ var (
 		},
 	)
 
+	getcontractstateCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getcontractstate rpc endpoint",
+			Name:      "getcontractstate_called",
+			Namespace: "neogo",
+		},
+	)
+
 	getversionCalled = prometheus.NewCounter(
 		prometheus.CounterOpts{
 			Help:      "Number of calls to getversion rpc endpoint",
@@ -124,6 +132,7 @@ func init() {
 		getblockcountCalled,
 		getblockHashCalled,
 		getconnectioncountCalled,
+		getcontractstateCalled,
 		getversionCalled,
 		getpeersCalled,
 		validateaddressCalled,

pkg/rpc/server.go

@@ -234,13 +234,17 @@ Methods:
 		if as != nil {
 			results = wrappers.NewAssetState(as)
 		} else {
-			results = "Invalid assetid"
+			resultsErr = NewRPCError("Unknown asset", "", nil)
 		}
 
 	case "getaccountstate":
 		getaccountstateCalled.Inc()
 		results, resultsErr = s.getAccountState(reqParams, false)
 
+	case "getcontractstate":
+		getcontractstateCalled.Inc()
+		results, resultsErr = s.getContractState(reqParams)
+
 	case "getrawtransaction":
 		getrawtransactionCalled.Inc()
 		results, resultsErr = s.getrawtransaction(reqParams)
@@ -288,7 +292,7 @@ func (s *Server) getrawtransaction(reqParams Params) (interface{}, error) {
 		resultsErr = errInvalidParams
 	} else if tx, height, err := s.chain.GetTransaction(txHash); err != nil {
 		err = errors.Wrapf(err, "Invalid transaction hash: %s", txHash)
-		return nil, NewInvalidParamsError(err.Error(), err)
+		return nil, NewRPCError("Unknown transaction", err.Error(), err)
 	} else if len(reqParams) >= 2 {
 		_header := s.chain.GetHeaderHash(int(height))
 		header, err := s.chain.GetHeader(_header)
@@ -349,6 +353,26 @@ func (s *Server) getTxOut(ps Params) (interface{}, error) {
 	return wrappers.NewTxOutput(&out), nil
 }
 
+// getContractState returns contract state (contract information, according to the contract script hash).
+func (s *Server) getContractState(reqParams Params) (interface{}, error) {
+	var results interface{}
+
+	param, ok := reqParams.ValueWithType(0, stringT)
+	if !ok {
+		return nil, errInvalidParams
+	} else if scriptHash, err := param.GetUint160FromHex(); err != nil {
+		return nil, errInvalidParams
+	} else {
+		cs := s.chain.GetContractState(scriptHash)
+		if cs != nil {
+			results = wrappers.NewContractState(cs)
+		} else {
+			return nil, NewRPCError("Unknown contract", "", nil)
+		}
+	}
+	return results, nil
+}
+
 // getAccountState returns account state either in short or full (unspents included) form.
 func (s *Server) getAccountState(reqParams Params, unspents bool) (interface{}, error) {
 	var resultsErr error

pkg/rpc/server_helper_test.go

@@ -13,6 +13,7 @@ import (
 	"github.com/CityOfZion/neo-go/pkg/network"
 	"github.com/CityOfZion/neo-go/pkg/rpc/result"
 	"github.com/CityOfZion/neo-go/pkg/rpc/wrappers"
+	"github.com/CityOfZion/neo-go/pkg/util"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/zap/zaptest"
 )
@@ -150,6 +151,29 @@ type GetUnspents struct {
 	ID int `json:"id"`
 }
 
+// GetContractStateResponse struct for testing.
+type GetContractStateResponce struct {
+	Jsonrpc string `json:"jsonrpc"`
+	Result  struct {
+		Version     byte         `json:"version"`
+		ScriptHash  util.Uint160 `json:"hash"`
+		Script      []byte       `json:"script"`
+		ParamList   interface{}  `json:"parameters"`
+		ReturnType  interface{}  `json:"returntype"`
+		Name        string       `json:"name"`
+		CodeVersion string       `json:"code_version"`
+		Author      string       `json:"author"`
+		Email       string       `json:"email"`
+		Description string       `json:"description"`
+		Properties  struct {
+			HasStorage       bool `json:"storage"`
+			HasDynamicInvoke bool `json:"dynamic_invoke"`
+			IsPayable        bool `json:"is_payable"`
+		} `json:"properties"`
+	} `json:"result"`
+	ID int `json:"id"`
+}
+
 func initServerWithInMemoryChain(t *testing.T) (*core.Blockchain, http.HandlerFunc) {
 	var nBlocks uint32
 
@@ -165,7 +189,13 @@ func initServerWithInMemoryChain(t *testing.T) (*core.Blockchain, http.HandlerFu
 
 	go chain.Run()
 
-	f, err := os.Open("testdata/50testblocks.acc")
+	// File "./testdata/testblocks.acc" was generated by function core._
+	// ("neo-go/pkg/core/helper_test.go").
+	// To generate new "./testdata/testblocks.acc", follow the steps:
+	// 		1. Rename the function
+	// 		2. Add specific test-case into "neo-go/pkg/core/blockchain_test.go"
+	// 		3. Run tests with `$ make test`
+	f, err := os.Open("testdata/testblocks.acc")
 	require.Nil(t, err)
 	br := io.NewBinReaderFromIO(f)
 	nBlocks = br.ReadU32LE()

pkg/rpc/server_test.go

@@ -72,6 +72,35 @@ var rpcTestCases = map[string][]rpcTestCase{
 			fail:   true,
 		},
 	},
+	"getcontractstate": {
+		{
+			name:   "positive",
+			params: `["6d1eeca891ee93de2b7a77eb91c26f3b3c04d6cf"]`,
+			result: func(e *executor) interface{} { return &GetContractStateResponce{} },
+			check: func(t *testing.T, e *executor, result interface{}) {
+				res, ok := result.(*GetContractStateResponce)
+				require.True(t, ok)
+				assert.Equal(t, byte(0), res.Result.Version)
+				assert.Equal(t, util.Uint160{0x6d, 0x1e, 0xec, 0xa8, 0x91, 0xee, 0x93, 0xde, 0x2b, 0x7a, 0x77, 0xeb, 0x91, 0xc2, 0x6f, 0x3b, 0x3c, 0x4, 0xd6, 0xcf}, res.Result.ScriptHash)
+				assert.Equal(t, "0.99", res.Result.CodeVersion)
+			},
+		},
+		{
+			name:   "negative",
+			params: `["6d1eeca891ee93de2b7a77eb91c26f3b3c04d6c3"]`,
+			fail:   true,
+		},
+		{
+			name:   "no params",
+			params: `[]`,
+			fail:   true,
+		},
+		{
+			name:   "invalid hash",
+			params: `["notahex"]`,
+			fail:   true,
+		},
+	},
 	"getassetstate": {
 		{
 			name:   "positive",
@@ -87,7 +116,7 @@ var rpcTestCases = map[string][]rpcTestCase{
 		{
 			name:   "negative",
 			params: `["602c79718b16e442de58778e148d0b1084e3b2dffd5de6b7b16cee7969282de2"]`,
-			result: func(e *executor) interface{} { return "Invalid assetid" },
+			fail:   true,
 		},
 		{
 			name:   "no params",

pkg/rpc/testdata/test_contract.avm

@@ -0,0 +1 @@
+QÅk
Hello, world!hNeo.Runtime.Logaluf

pkg/rpc/wrappers/account_state.go

@@ -45,10 +45,7 @@ func NewAccountState(a *state.Account) AccountState {
 	sort.Sort(balances)
 
 	// reverse scriptHash to be consistent with other client
-	scriptHash, err := util.Uint160DecodeBytesBE(a.ScriptHash.BytesLE())
+	scriptHash := a.ScriptHash.Reverse()
-	if err != nil {
-		scriptHash = a.ScriptHash
-	}
 
 	return AccountState{
 		Version:    a.Version,

pkg/rpc/wrappers/contract_state.go

@@ -0,0 +1,56 @@
+package wrappers
+
+import (
+	"github.com/CityOfZion/neo-go/pkg/core/state"
+	"github.com/CityOfZion/neo-go/pkg/smartcontract"
+	"github.com/CityOfZion/neo-go/pkg/util"
+)
+
+// ContractState wrapper used for the representation of
+// state.Contract on the RPC Server.
+type ContractState struct {
+	Version     byte                      `json:"version"`
+	ScriptHash  util.Uint160              `json:"hash"`
+	Script      []byte                    `json:"script"`
+	ParamList   []smartcontract.ParamType `json:"parameters"`
+	ReturnType  smartcontract.ParamType   `json:"returntype"`
+	Name        string                    `json:"name"`
+	CodeVersion string                    `json:"code_version"`
+	Author      string                    `json:"author"`
+	Email       string                    `json:"email"`
+	Description string                    `json:"description"`
+	Properties  Properties                `json:"properties"`
+}
+
+// Properties response wrapper.
+type Properties struct {
+	HasStorage       bool `json:"storage"`
+	HasDynamicInvoke bool `json:"dynamic_invoke"`
+	IsPayable        bool `json:"is_payable"`
+}
+
+// NewContractState creates a new Contract wrapper.
+func NewContractState(c *state.Contract) ContractState {
+	// reverse scriptHash to be consistent with other client
+	scriptHash := c.ScriptHash().Reverse()
+
+	properties := Properties{
+		HasStorage:       c.HasStorage(),
+		HasDynamicInvoke: c.HasDynamicInvoke(),
+		IsPayable:        c.IsPayable(),
+	}
+
+	return ContractState{
+		Version:     0,
+		ScriptHash:  scriptHash,
+		Script:      c.Script,
+		ParamList:   c.ParamList,
+		ReturnType:  c.ReturnType,
+		Properties:  properties,
+		Name:        c.Name,
+		CodeVersion: c.CodeVersion,
+		Author:      c.Author,
+		Email:       c.Email,
+		Description: c.Description,
+	}
+}