vspd: Move vspd code to its own file.

Moving all vspd code into its own vspd.go file (fka background.go). This
leaves main.go as a minimal entry point for the vspd executable.

cmd/vspd/main.go

@@ -5,30 +5,10 @@
 package main
 
 import (
-	"context"
 	"fmt"
 	"os"
-	"runtime"
-	"sync"
-	"time"
-
-	"github.com/decred/dcrd/wire"
-	"github.com/decred/slog"
-	"github.com/decred/vspd/database"
-	"github.com/decred/vspd/rpc"
-	"github.com/decred/vspd/version"
-	"github.com/decred/vspd/webapi"
 )
 
-// maxVoteChangeRecords defines how many vote change records will be stored for
-// each ticket. The limit is in place to mitigate DoS attacks on server storage
-// space. When storing a new record breaches this limit, the oldest record in
-// the database is deleted.
-const maxVoteChangeRecords = 10
-
-// consistencyInterval is the time period between wallet consistency checks.
-const consistencyInterval = 30 * time.Minute
-
 func main() {
 	// Load config file and parse CLI args.
 	cfg, err := loadConfig()
@@ -46,173 +26,3 @@ func main() {
 	// Run until an exit code is returned.
 	os.Exit(vspd.run())
 }
-
-type vspd struct {
-	cfg         *config
-	log         slog.Logger
-	shutdownCtx context.Context
-	db          *database.VspDatabase
-	dcrd        rpc.DcrdConnect
-	wallets     rpc.WalletConnect
-}
-
-// newVspd creates the essential resources required by vspd - a database, logger
-// and RPC clients - then returns an instance of vspd which is ready to be run.
-func newVspd(cfg *config) (*vspd, error) {
-
-	// Open database.
-	db, err := database.Open(cfg.dbPath, cfg.logger(" DB"), maxVoteChangeRecords)
-	if err != nil {
-		return nil, fmt.Errorf("failed to open database: %w", err)
-	}
-
-	log := cfg.logger("VSP")
-	rpcLog := cfg.logger("RPC")
-
-	// Create RPC client for local dcrd instance (used for broadcasting and
-	// checking the status of fee transactions).
-	dcrd := rpc.SetupDcrd(cfg.DcrdUser, cfg.DcrdPass, cfg.DcrdHost, cfg.dcrdCert, cfg.netParams.Params, rpcLog)
-
-	// Create RPC client for remote dcrwallet instances (used for voting).
-	wallets := rpc.SetupWallet(cfg.walletUsers, cfg.walletPasswords, cfg.walletHosts, cfg.walletCerts, cfg.netParams.Params, rpcLog)
-
-	v := &vspd{
-		cfg:         cfg,
-		log:         log,
-		shutdownCtx: shutdownListener(log),
-		db:          db,
-		dcrd:        dcrd,
-		wallets:     wallets,
-	}
-
-	return v, nil
-}
-
-// run starts all of vspds background services including the web server, and
-// stops all started services when a shutdown is requested.
-func (v *vspd) run() int {
-
-	v.log.Criticalf("Version %s (Go version %s %s/%s)", version.String(), runtime.Version(),
-		runtime.GOOS, runtime.GOARCH)
-
-	if v.cfg.netParams == &mainNetParams &&
-		version.PreRelease != "" {
-		v.log.Warnf("")
-		v.log.Warnf("\tWARNING: This is a pre-release version of vspd which should not be used on mainnet.")
-		v.log.Warnf("")
-	}
-
-	if v.cfg.VspClosed {
-		v.log.Warnf("")
-		v.log.Warnf("\tWARNING: Config --vspclosed is set. This will prevent vspd from accepting new tickets.")
-		v.log.Warnf("")
-	}
-
-	// Defer shutdown tasks.
-	defer v.log.Criticalf("Shutdown complete")
-	const writeBackup = true
-	defer v.db.Close(writeBackup)
-	defer v.dcrd.Close()
-	defer v.wallets.Close()
-
-	// WaitGroup for services to signal when they have shutdown cleanly.
-	var shutdownWg sync.WaitGroup
-
-	v.db.WritePeriodicBackups(v.shutdownCtx, &shutdownWg, v.cfg.BackupInterval)
-
-	// Ensure all data in database is present and up-to-date.
-	err := v.db.CheckIntegrity(v.dcrd)
-	if err != nil {
-		// vspd should still start if this fails, so just log an error.
-		v.log.Errorf("Could not check database integrity: %v", err)
-	}
-
-	// Run the block connected handler now to catch up with any blocks mined
-	// while vspd was shut down.
-	v.blockConnected()
-
-	// Run voting wallet consistency check now to ensure all wallets are up to
-	// date.
-	v.checkWalletConsistency()
-
-	// Run voting wallet consistency check periodically.
-	shutdownWg.Add(1)
-	go func() {
-		for {
-			select {
-			case <-v.shutdownCtx.Done():
-				shutdownWg.Done()
-				return
-			case <-time.After(consistencyInterval):
-				v.checkWalletConsistency()
-			}
-		}
-	}()
-
-	// Create and start webapi server.
-	apiCfg := webapi.Config{
-		VSPFee:               v.cfg.VSPFee,
-		NetParams:            v.cfg.netParams.Params,
-		BlockExplorerURL:     v.cfg.netParams.blockExplorerURL,
-		SupportEmail:         v.cfg.SupportEmail,
-		VspClosed:            v.cfg.VspClosed,
-		VspClosedMsg:         v.cfg.VspClosedMsg,
-		AdminPass:            v.cfg.AdminPass,
-		Debug:                v.cfg.WebServerDebug,
-		Designation:          v.cfg.Designation,
-		MaxVoteChangeRecords: maxVoteChangeRecords,
-		VspdVersion:          version.String(),
-	}
-	err = webapi.Start(v.shutdownCtx, requestShutdown, &shutdownWg, v.cfg.Listen, v.db, v.cfg.logger("API"),
-		v.dcrd, v.wallets, apiCfg)
-	if err != nil {
-		v.log.Errorf("Failed to initialize webapi: %v", err)
-		requestShutdown()
-		shutdownWg.Wait()
-		return 1
-	}
-
-	// Create a channel to receive blockConnected notifications from dcrd.
-	notifChan := make(chan *wire.BlockHeader)
-	shutdownWg.Add(1)
-	go func() {
-		for {
-			select {
-			case <-v.shutdownCtx.Done():
-				shutdownWg.Done()
-				return
-			case header := <-notifChan:
-				v.log.Debugf("Block notification %d (%s)", header.Height, header.BlockHash().String())
-				v.blockConnected()
-			}
-		}
-	}()
-
-	// Attach notification listener to dcrd client.
-	v.dcrd.BlockConnectedHandler(notifChan)
-
-	// Loop forever attempting ensuring a dcrd connection is available, so
-	// notifications are received.
-	shutdownWg.Add(1)
-	go func() {
-		for {
-			select {
-			case <-v.shutdownCtx.Done():
-				shutdownWg.Done()
-				return
-			case <-time.After(time.Second * 15):
-				// Ensure dcrd client is still connected.
-				_, _, err := v.dcrd.Client()
-				if err != nil {
-					v.log.Errorf("dcrd connect error: %v", err)
-				}
-			}
-		}
-	}()
-
-	// Wait for shutdown tasks to complete before running deferred tasks and
-	// returning.
-	shutdownWg.Wait()
-
-	return 0
-}