rpcserver: Add existsmissedtickets RPC.

This RPC works identically to the existsexpiredtickets RPC but checks
for missed rather than expired tickets.

blockchain/stakeext.go

@@ -173,6 +173,23 @@ func (b *BlockChain) CheckLiveTickets(hashes []chainhash.Hash) []bool {
 	return existsSlice
 }
 
+// CheckMissedTickets returns a slice of bools representing whether each ticket
+// hash has been missed in the live ticket treap of the best node.
+//
+// This function is safe for concurrent access.
+func (b *BlockChain) CheckMissedTickets(hashes []chainhash.Hash) []bool {
+	b.chainLock.RLock()
+	sn := b.bestNode.stakeNode
+	b.chainLock.RUnlock()
+
+	existsSlice := make([]bool, len(hashes))
+	for i := range hashes {
+		existsSlice[i] = sn.ExistsMissedTicket(hashes[i])
+	}
+
+	return existsSlice
+}
+
 // CheckExpiredTicket returns whether or not a ticket was ever expired.
 //
 // This function is safe for concurrent access.

dcrjson/dcrdcmds.go

@@ -45,6 +45,19 @@ func NewExistsAddressesCmd(addresses []string) *ExistsAddressesCmd {
 	}
 }
 
+// ExistsMissedTicketsCmd defines the existsmissedtickets JSON-RPC command.
+type ExistsMissedTicketsCmd struct {
+	TxHashBlob string
+}
+
+// NewExistsMissedTicketsCmd returns a new instance which can be used to issue an
+// existsmissedtickets JSON-RPC command.
+func NewExistsMissedTicketsCmd(txHashBlob string) *ExistsMissedTicketsCmd {
+	return &ExistsMissedTicketsCmd{
+		TxHashBlob: txHashBlob,
+	}
+}
+
 // ExistsExpiredTicketsCmd defines the existsexpiredtickets JSON-RPC command.
 type ExistsExpiredTicketsCmd struct {
 	TxHashBlob string
@@ -281,6 +294,7 @@ func init() {
 	MustRegisterCmd("estimatestakediff", (*EstimateStakeDiffCmd)(nil), flags)
 	MustRegisterCmd("existsaddress", (*ExistsAddressCmd)(nil), flags)
 	MustRegisterCmd("existsaddresses", (*ExistsAddressesCmd)(nil), flags)
+	MustRegisterCmd("existsmissedtickets", (*ExistsMissedTicketsCmd)(nil), flags)
 	MustRegisterCmd("existsexpiredtickets", (*ExistsExpiredTicketsCmd)(nil), flags)
 	MustRegisterCmd("existsliveticket", (*ExistsLiveTicketCmd)(nil), flags)
 	MustRegisterCmd("existslivetickets", (*ExistsLiveTicketsCmd)(nil), flags)

rpcserver.go

@@ -187,6 +187,7 @@ var rpcHandlersBeforeInit = map[string]commandHandler{
 	"estimatestakediff":     handleEstimateStakeDiff,
 	"existsaddress":         handleExistsAddress,
 	"existsaddresses":       handleExistsAddresses,
+	"existsmissedtickets":   handleExistsMissedTickets,
 	"existsexpiredtickets":  handleExistsExpiredTickets,
 	"existsliveticket":      handleExistsLiveTicket,
 	"existslivetickets":     handleExistsLiveTickets,
@@ -1605,6 +1606,32 @@ func handleExistsAddresses(s *rpcServer, cmd interface{}, closeChan <-chan struc
 	return hex.EncodeToString([]byte(set)), nil
 }
 
+// handleExistsMissedTickets implements the existsmissedtickets command.
+func handleExistsMissedTickets(s *rpcServer, cmd interface{}, closeChan <-chan struct{}) (interface{}, error) {
+	c := cmd.(*dcrjson.ExistsMissedTicketsCmd)
+
+	hashes, err := dcrjson.DecodeConcatenatedHashes(c.TxHashBlob)
+	if err != nil {
+		return nil, err
+	}
+
+	exists := s.server.blockManager.chain.CheckMissedTickets(hashes)
+	if len(exists) != len(hashes) {
+		return nil, rpcInvalidError("Invalid missed ticket count "+
+			"got %v, want %v", len(exists), len(hashes))
+	}
+
+	// Convert the slice of bools into a compacted set of bit flags.
+	set := bitset.NewBytes(len(hashes))
+	for i := range exists {
+		if exists[i] {
+			set.Set(i)
+		}
+	}
+
+	return hex.EncodeToString([]byte(set)), nil
+}
+
 // handleExistsExpiredTickets implements the existsexpiredtickets command.
 func handleExistsExpiredTickets(s *rpcServer, cmd interface{}, closeChan <-chan struct{}) (interface{}, error) {
 	c := cmd.(*dcrjson.ExistsExpiredTicketsCmd)

rpcserverhelp.go

@@ -171,6 +171,11 @@ var helpDescsEnUS = map[string]string{
 	"existsaddresses-addresses": "The addresses to check",
 	"existsaddresses--result0":  "Bitset of bools showing if addresses exist or not",
 
+	// ExitsMissedTicketsCmd help.
+	"existsmissedtickets--synopsis":  "Test for the existance of the provided tickets in the missed ticket map",
+	"existsmissedtickets-txhashblob": "Blob containing the hashes to check",
+	"existsmissedtickets--result0":   "Bool blob showing if the ticket exists in the missed ticket database or not",
+
 	// ExistsExpiredTicketsCmd help.
 	"existsexpiredtickets--synopsis":  "Test for the existance of the provided tickets in the expired ticket map",
 	"existsexpiredtickets-txhashblob": "Blob containing the hashes to check",
@@ -879,6 +884,7 @@ var rpcResultTypes = map[string][]interface{}{
 	"estimatestakediff":     {(*dcrjson.EstimateStakeDiffResult)(nil)},
 	"existsaddress":         {(*bool)(nil)},
 	"existsaddresses":       {(*string)(nil)},
+	"existsmissedtickets":   {(*string)(nil)},
 	"existsexpiredtickets":  {(*string)(nil)},
 	"existsliveticket":      {(*bool)(nil)},
 	"existslivetickets":     {(*string)(nil)},