This document summarizes a Go server for a mobile strategy game. It discusses using various Go libraries and frameworks including gocraft/web for routing, gocraft/dbr for database access, gocraft/health for monitoring, and pmylund/go-cache for caching. It provides examples of setting up routers, middleware, database models and queries, health tracking, and caching static data.

1. Сервер на Go для мобильной стратегии
armor5games.com

3. github.com/gocraft/web
github.com/gocraft/dbr
github.com/gocraft/health
github.com/penlook/daemon
github.com/pmylund/go-cache
bonus/dbr

4. github.com/gocraft/web
Routers
Context
Middleware

5. type Context struct {
ReadSession *dbr.Session
WriteSession *dbr.Session
HealthStream *health.Stream
Cache *cache.Cache
User *user.Params
}
router := web.New(context.Context{}).
Middleware((*context.Context).AddDbrSession).
Middleware((*context.Context).LogURL)
router.Get("/crossdomain.xml",CrossDomainHandler)

6. func (c *Context) AddDbrSession(rw web.ResponseWriter, req *web.Request,
next web.NextMiddlewareFunc) {
c.HealthStream = health.NewStream()
c.ReadSession = GetReadSession()
c.WriteSession = GetWriteSession()
next(rw, req)
}
func CrossDomainHandler(rw web.ResponseWriter, req *web.Request) {
rw.Header().Set("Content-type", "application/xml; charset=utf-8")
fmt.Fprintln(rw, `<?xml version="1.0"?>
<cross-domain-policy>
<allow-access-from domain="*"/>
</cross-domain-policy>`)
}

7. userRouter := router.Subrouter(context.Context{}, "/user")
userRouter.Middleware((*context.Context).UserRequired)
userRouter.Get("/", user.UserGet)
func (c *Context) UserRequired(rw web.ResponseWriter, req *web.Request,
next web.NextMiddlewareFunc) {
c.User := new(user.Params)
if err := c.User.LoadFromAccessToken(req); err == nil {
go userLastActive(c)
next(rw, req)
return
}
fmt.Fprintln(rw, “invalid access token”)
}

8. func UserGet(c *context.Context, rw web.ResponseWriter, req *web.Request) {
job := c.HealthStream.NewJob("user/get")
answer.AnswerJson(c.User, rw, req)
job.Complete(health.Success)
}

9. github.com/gocraft/dbr
MySql
Query Builder
Transactions
Interpolate

10. type UserParams struct {
ID int64 `db:"ID"`
Name string `db:"Name"`
AccessToken dbr.NullString `db:"AccessToken"`
}
func LoadFromAccessToken(req *web.Request) {
user_params := new(UserParams)
err := ReadSession.Select("*").From("users").
Where("AccessToken=?", req.GetAccessToken()).
LoadStruct(user_params)
return err
}

11. func userLastActive(c *Context) {
c.WriteSession.
Update("user_session").Set("Last", time.Now().Unix()).Where("User=?", c.
User.ID).
Exec()
}

12. type User_stats struct {
User int64 `db:"User"`
AdvWins int64 `db:"AdvWins"`
AdvLose int64 `db:"AdvLose"`
DailyWin int64 `db:"DailyWin"`
DailyLose int64 `db:"DailyLose"`
PvpaAttacks int64 `db:"PvpaAttacks"`
PvpaWins int64 `db:"PvpaWins"`
PvpaDefs int64 `db:"PvpaDefs"`
Sieges int64 `db:"Sieges"`
SiegesWins int64 `db:"SiegesWins"`
SiegesDefs int64 `db:"SiegesDefs"`
}

13. func CreateUserStatistics() error {
stats := new(User_stats)
tx, err := WriteSession.Begin()
defer tx.RollbackUnlessCommitted()
result, err := tx.InsertInto("user_stats").
Columns("User", "AdvWins", "AdvLose", "DailyWin", "DailyLose",
"PvpaAttacks", "PvpaWins", "PvpaDefs",
"Sieges", "SiegesWins", "SiegesDefs").
Record(stats).Exec()
tx.Commit()
}

14. github.com/gocraft/health
Jobs
Events
Timings
Errors

15. var stream = health.NewStream()
// jsonSink for healthTop
sink := health.NewJsonPollingSink(time.Minute, time.Minute * 5)
stream.AddSink(sink)
// stdout sink
stream.AddSink(&health.WriterSink{os.Stdout})
// https://bugsnag.com/ sink
stream.AddSink(bugsnag.NewSink(&bugsnag.Config{APIKey: "supersecretapikey"}))

16. func UserBuildingsUpgrade(c *context.Context, rw web.ResponseWriter,
req *web.Request) {
job := c.HealthStream.NewJob(“user/building/upgrade”)
type := req.GetBuildingType()
if isBuildingTypeValid(type) == false {
answer.answerErrorString(“invalid building type”, rw, req)
job.Event(“invalid building type”)
job.Complete(health.Junk)
return
}
if c.User.Money < getBuildingUpgradePrice(type) {
answer.answerErrorString(“no money”, rw, req)
job.EventKv(“cheater detected”,
map[string]string{“User” : c.User.ID, “cheater” : ”true”})
job.Complete(health.Junk)
return
}

17. if err := buildingUpgrade(type, c.User); err != nil {
answer.answerErrorString(“db error”, rw, req)
job.EventErr(“buildingUpgrade: ”, err)
job.Complete(health.Error)
return
}
if err := userMoneyMinus(c.User, price); err != nil {
answer.answerErrorString(“db error”, rw, req)
job.EventErr(“userMoneyMinus: ”, err)
job.Complete(health.Error)
return
}
job.Complete(health.Success)
}

18. github.com/penlook/daemon
Service
Signals
Daemon

19. ...
go serv.Serve(listener)
interrupt := make(chan os.Signal, 1)
signal.Notify(interrupt, os.Interrupt, os.Kill, syscall.SIGTERM)
for {
select {
case killSignal := <-interrupt:
stdlog.Println("Got signal:", killSignal)
stdlog.Println("Stoping listening on ", serv.Addr)
listener.Close()
if killSignal == os.Interrupt {
return "Daemon was interruped by system signal", nil
}
return "Daemon was killed", nil
}
}

20. github.com/pmylund/go-cache
Cache
Cache
Cache
Cache

21. package context
c.Cache = cache.New(time.Minute * 100, time.Minute * 1)
----------------------------------------------------------------------------
package static
import (
"strconv"
"github.com/gocraft/web"
"github.com/pmylund/go-cache"
)
const (
CACHE_STATIC_EQUIP string = "static/equip"
)

22. func StaticEquip(c *context.Context, rw web.ResponseWriter, req *web.Request) {
if data, ok := c.Cache.Get(CACHE_STATIC_EQUIP); ok {
answer.CachedAnswer(data, rw, req)
return
}
var equips []*Equip
_, err := c.ReadSession.Select("*").From("equipments").LoadStructs(&equips)
forCache := make(map[string][]*Equip)
forCache[“Equip”] = equips
answerJsonString := json.Marshal(&forCache)
c.Cache.Set(CACHE_STATIC_EQUIP, answerJsonString,
cache.DefaultExpiration)
answer.CachedAnswer(answerJsonString, rw, req)
}

23. Bonus
Эрик Реймонд: Искусство программирования в UNIX
Правило генерации:
Избегайте ручного набора кода; при любом удобном случае пишите
программы, которые бы писали программы.

24. CREATE TABLE Persons
(
PersonID int,
LastName varchar(255),
FirstName varchar(255),
Address varchar(255),
City varchar(255)
);
type Persons struct {
PersonID int64 `db:"PersonID"`
LastName string `db:"LastName"`
FirstName string `db:"FirstName"`
Address dbr.NullString `db:"Address"`
City dbr.NullString `db:"City"`
}

25. "show full tables where Table_Type != 'VIEW'"

26. package databasemodels
import {{.DbrUsed}}"github.com/gocraft/dbr"
type {{.Table}} struct {
{{range .Fields}}{{.Name}} {{.Type}} {{.Tag}}
{{end}}
}

27. Виталий Симирнин
finalist736@gmail.com
https://golang-ru.slack.com/team/finalist
Armor5Games.com
armor5games@gmail.com