trantor/lib/stats.go

package trantor

import (
	log "github.com/cihub/seelog"

	"net/http"
	"strings"
	"time"

	"github.com/gorilla/mux"
	"gitlab.com/trantor/trantor/lib/database"
	"gitlab.com/trantor/trantor/lib/storage"
)

const (
	stats_version = 2
	statsChanSize = 100
)

type handler struct {
	w        http.ResponseWriter
	r        *http.Request
	sess     *Session
	db       database.DB
	store    storage.Store
	template *Template
	hostname string
	ro       bool
}

type StatsGatherer struct {
	db       database.DB
	store    storage.Store
	template *Template
	hostname string
	channel  chan statsRequest
	ro       bool
}

func InitStats(database database.DB, store storage.Store, hostname string, template *Template, ro bool) *StatsGatherer {
	sg := StatsGatherer{
		channel:  make(chan statsRequest, statsChanSize),
		db:       database,
		store:    store,
		template: template,
		hostname: hostname,
		ro:       ro,
	}

	go sg.worker()
	return &sg
}

func (sg StatsGatherer) Gather(function func(handler)) func(http.ResponseWriter, *http.Request) {
	return func(w http.ResponseWriter, r *http.Request) {
		log.Info("Query ", r.Method, " ", r.RequestURI)

		h := handler{
			store:    sg.store,
			db:       sg.db,
			template: sg.template,
			hostname: sg.hostname,
			w:        w,
			r:        r,
			sess:     GetSession(r, sg.db),
			ro:       sg.ro,
		}

		function(h)
		sg.channel <- statsRequest{time.Now(), mux.Vars(r), h.sess, r}
	}
}

type statsRequest struct {
	date time.Time
	vars map[string]string
	sess *Session
	r    *http.Request
}

func (sg StatsGatherer) worker() {
	for req := range sg.channel {
		stats := make(map[string]interface{})
		appendFiles(req.r, stats)
		appendMuxVars(req.vars, stats)
		appendUrl(req.r, stats)
		appendSession(req.sess, stats)
		stats["version"] = stats_version
		stats["method"] = req.r.Method
		stats["date"] = req.date
		sg.db.AddStats(stats)
	}
}

func appendFiles(r *http.Request, stats map[string]interface{}) {
	if r.Method == "POST" && r.MultipartForm != nil {
		files := r.MultipartForm.File
		for key := range files {
			list := make([]string, len(files[key]))
			for i, f := range files[key] {
				list[i] = f.Filename
			}
			stats[key] = list
		}
	}
}

func appendMuxVars(vars map[string]string, stats map[string]interface{}) {
	for key, value := range vars {
		switch {
		case key == "id":
			stats["id"] = value
		case key == "ids":
			var objectIds []string
			ids := strings.Split(value, "/")
			for _, id := range ids {
				objectIds = append(objectIds, id)
			}
			if len(objectIds) > 0 {
				stats["ids"] = objectIds
				stats["id"] = objectIds[0]
			}
		default:
			stats[key] = value
		}
	}
}

func appendUrl(r *http.Request, stats map[string]interface{}) {
	for key, value := range r.URL.Query() {
		stats[key] = value
	}
	stats["host"] = r.Host
	stats["path"] = r.URL.Path
	pattern := strings.Split(r.URL.Path, "/")
	if len(pattern) > 1 && pattern[1] != "" {
		stats["section"] = pattern[1]
	} else {
		stats["section"] = "/"
	}
}

func appendSession(sess *Session, stats map[string]interface{}) {
	stats["session"] = sess.Id()
	if sess.User != "" {
		stats["user"] = sess.User
	}
}