multi: improve handling of low fee tickets

README.md

@@ -16,6 +16,34 @@ vote on their behalf when the ticket is selected.
 - The architecture is subject to change in the future to lessen the dependence
   on dcrwallet and MySQL.
 
+## Git Tip Release notes
+
+- The handling of tickets considered invalid because they pay too-low-of-a-fee
+is now integrated directly into dcrstakepool and stakepoold.
+  - Users who pass both the adminIPs and the new adminUserIDs checks will see a new link on the
+menu to the new administrative add tickets page.
+  - Tickets are added to the MySQL database and then stakepoold is triggered to pull an update from the
+database and reload its config.
+  - To accommodate changes to the gRPC API, dcrstakepool/stakepoold had
+  their API versions changed to require/advertize 4.0.0. This requires
+  performing the upgrade steps outlined below.
+- **KNOWN ISSUE** Total tickets count reported by stakepoold may
+  not be totally accurate until low fee tickets that have been added to
+  the database can be marked as voted.  This will be resolved by future work. ([#201](https://github.com/decred/dcrstakepool/issues/201)).
+
+## Git Tip Upgrade Guide
+
+1) Announce maintenance and shut down dcrstakepool.
+2) Upgrade Go to the latest stable version if necessary/possible.
+3) Perform an upgrade of each stakepoold instance one at a time.
+   * Stop stakepoold.
+   * Build and restart stakepoold.
+4) Edit dcrstakepool.conf and set adminIPs/adminUserIDs appropriately to include
+   the administrative staff for whom you wish give the ability to add low fee
+   tickets for voting.
+5) Upgrade and start dcrstakepool after setting adminUserIDs.
+6) Announce maintenance complete after verifying functionality.
+
 ## 1.1.1 Release Notes
 
 - dcrd has a new agenda and the vote version in dcrwallet has been
@@ -249,6 +277,17 @@ If you are modifying templates, sending the USR1 signal to the dcrstakepool proc
 
 ## Adding Invalid Tickets
 
+#### For Newer versions / git tip
+
+If a user pays an incorrect fee, login as an account that meets the
+adminUserIps and adminUserIds restrictions and click the 'Add Low Fee Tickets'
+link in the menu.  You will be presented with a list of tickets that are
+suitable for adding.  Check the appropriate one(s) and click the submit button.
+Upon success, you should see the stakepoold logs reflect that the new tickets
+were processed.
+
+#### For v1.1.1 and below
+
 If a user pays an incorrect fee you may add their tickets like so (requires dcrd running with txindex=1):
 
 ```bash

backend/stakepoold/grpcserver.go

@@ -6,6 +6,7 @@
 package main
 
 import (
+	"context"
 	"crypto/elliptic"
 	"crypto/tls"
 	"errors"
@@ -22,6 +23,7 @@ import (
 
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/peer"
 )
 
 // generateRPCKeyPair generates a new RPC TLS keypair and writes the cert and
@@ -76,6 +78,37 @@ func generateRPCKeyPair(writeKey bool) (tls.Certificate, error) {
 	return keyPair, nil
 }
 
+func interceptUnary(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (resp interface{}, err error) {
+	startTime := time.Now()
+
+	// parse out method from '/package.service/method'
+	methodSplit := strings.SplitAfterN(info.FullMethod, "/", 3)
+	method := methodSplit[2]
+	peer, peerOk := peer.FromContext(ctx)
+
+	// limit the time we take
+	ctx, cancel := context.WithTimeout(ctx, rpcserver.GRPCCommandTimeout)
+	// it is good practice to use the cancellation function even with a timeout
+	defer cancel()
+
+	resp, err = handler(ctx, req)
+	if err != nil && peerOk {
+		grpcLog.Errorf("%s invoked by %s failed: %v",
+			method, peer.Addr.String(), err)
+	}
+
+	defer func() {
+		if peerOk {
+			grpcLog.Infof("%s invoked by %s processed in %v", method,
+				peer.Addr.String(), time.Since(startTime))
+		} else {
+			grpcLog.Infof("%s processed in %v", method,
+				time.Since(startTime))
+		}
+	}()
+	return resp, err
+}
+
 type listenFunc func(net string, laddr string) (net.Listener, error)
 
 // makeListeners splits the normalized listen addresses into IPv4 and IPv6
@@ -153,7 +186,7 @@ func openRPCKeyPair() (tls.Certificate, error) {
 	return tls.LoadX509KeyPair(cfg.RPCCert, cfg.RPCKey)
 }
 
-func startGRPCServers(c chan struct{}) (*grpc.Server, error) {
+func startGRPCServers(grpcCommandQueueChan chan *rpcserver.GRPCCommandQueue) (*grpc.Server, error) {
 	var (
 		server  *grpc.Server
 		keyPair tls.Certificate
@@ -171,9 +204,9 @@ func startGRPCServers(c chan struct{}) (*grpc.Server, error) {
 		return nil, err
 	}
 	creds := credentials.NewServerTLSFromCert(&keyPair)
-	server = grpc.NewServer(grpc.Creds(creds))
+	server = grpc.NewServer(grpc.Creds(creds), grpc.UnaryInterceptor(interceptUnary))
 	rpcserver.StartVersionService(server)
-	rpcserver.StartStakepooldService(c, server)
+	rpcserver.StartStakepooldService(grpcCommandQueueChan, server)
 	for _, lis := range listeners {
 		lis := lis
 		go func() {

backend/stakepoold/rpc/api.proto

@@ -3,24 +3,59 @@ syntax = "proto3";
 package stakepoolrpc;
 
 service StakepooldService {
-	// Queries
+	rpc GetAddedLowFeeTickets (GetAddedLowFeeTicketsRequest) returns (GetAddedLowFeeTicketsResponse);
+	rpc GetIgnoredLowFeeTickets (GetIgnoredLowFeeTicketsRequest) returns (GetIgnoredLowFeeTicketsResponse);
+	rpc GetLiveTickets (GetLiveTicketsRequest) returns (GetLiveTicketsResponse);
 	rpc Ping (PingRequest) returns (PingResponse);
-
-	// Control
-	rpc UpdateVotingPrefs (UpdateVotingPrefsRequest) returns (UpdateVotingPrefsResponse);
+	rpc SetAddedLowFeeTickets (SetAddedLowFeeTicketsRequest) returns (SetAddedLowFeeTicketsResponse);
+	rpc SetUserVotingPrefs (SetUserVotingPrefsRequest) returns (SetUserVotingPrefsResponse);
 }
 
 service VersionService {
 	rpc Version (VersionRequest) returns (VersionResponse);
 }
 
+message GetAddedLowFeeTicketsRequest {}
+message GetAddedLowFeeTicketsResponse {
+	repeated TicketEntry tickets = 1;
+}
+
+message GetIgnoredLowFeeTicketsRequest {}
+message GetIgnoredLowFeeTicketsResponse {
+	repeated TicketEntry tickets = 1;
+}
+
+message GetLiveTicketsRequest {}
+message GetLiveTicketsResponse {
+	repeated TicketEntry tickets = 1;
+}
+
 message PingRequest {}
 message PingResponse {}
 
-message UpdateVotingPrefsRequest {
-	int64 Userid = 1;
+message SetAddedLowFeeTicketsRequest {
+	repeated TicketEntry tickets = 1;
+}
+message SetAddedLowFeeTicketsResponse {
+}
+
+message SetUserVotingPrefsResponse {
+}
+message SetUserVotingPrefsRequest {
+	repeated UserVotingConfigEntry user_voting_config = 1;
+}
+
+message TicketEntry {
+	string TicketAddress = 1;
+	bytes TicketHash = 2;
+}
+
+message UserVotingConfigEntry {
+  int64 UserId = 1;
+  string MultiSigAddress = 2;
+  int64 VoteBits = 3;
+  int64 VoteBitsVersion = 4;
 }
-message UpdateVotingPrefsResponse {}
 
 message VersionRequest {}
 message VersionResponse {