zones: per zone server counts API migrated

server/zones.go

@@ -0,0 +1,148 @@
+package server
+
+import (
+	"database/sql"
+	"errors"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/labstack/echo/v4"
+	"go.ntppool.org/common/logger"
+	"go.ntppool.org/common/tracing"
+	"go.ntppool.org/data-api/ntpdb"
+)
+
+func (srv *Server) zoneCounts(c echo.Context) error {
+	log := logger.Setup()
+	ctx, span := tracing.Tracer().Start(c.Request().Context(), "zoneCounts")
+	defer span.End()
+
+	// just cache for a short time by default
+	c.Response().Header().Set("Cache-Control", "public,max-age=240")
+	c.Response().Header().Set("Access-Control-Allow-Origin", "*")
+	c.Response().Header().Del("Vary")
+
+	q := ntpdb.NewWrappedQuerier(ntpdb.New(srv.db))
+
+	zone, err := q.GetZoneByName(ctx, c.Param("zone_name"))
+	if err != nil || zone.ID == 0 {
+		if errors.Is(err, sql.ErrNoRows) {
+			return c.String(http.StatusNotFound, "Not found")
+		}
+		log.ErrorContext(ctx, "could not query for zone", "err", err)
+		span.RecordError(err)
+		return echo.NewHTTPError(http.StatusInternalServerError, "internal error")
+	}
+
+	counts, err := q.GetZoneCounts(ctx, zone.ID)
+	if err != nil {
+		if !errors.Is(err, sql.ErrNoRows) {
+			log.ErrorContext(ctx, "get counts", "err", err)
+			span.RecordError(err)
+			return c.String(http.StatusInternalServerError, "internal error")
+		}
+	}
+
+	type historyEntry struct {
+		D  string `json:"d"`  // date
+		Ts int    `json:"ts"` // epoch timestamp
+		Rc int    `json:"rc"` // count registered
+		Ac int    `json:"ac"` // count active
+		W  int    `json:"w"`  // netspeed active
+		Iv string `json:"iv"` // ip version
+	}
+
+	rv := struct {
+		History []historyEntry `json:"history"`
+	}{}
+
+	skipCount := 0.0
+	limit := 0
+
+	if limitParam := c.QueryParam("limit"); len(limitParam) > 0 {
+		if limitInt, err := strconv.Atoi(limitParam); err == nil && limitInt > 0 {
+			limit = limitInt
+		}
+	}
+
+	var mostRecentDate int64 = -1
+	if limit > 0 {
+		count := 0
+		dates := map[int64]bool{}
+		for _, c := range counts {
+			ep := c.Date.Unix()
+			if _, ok := dates[ep]; !ok {
+				count++
+				dates[ep] = true
+				mostRecentDate = ep
+			}
+		}
+		if limit < count {
+			if limit > 1 {
+				skipCount = float64(count) / float64(limit-1)
+			} else {
+				// skip everything and use the special logic that we always include the most recent date
+				skipCount = float64(count) + 1
+
+			}
+		}
+
+		log.DebugContext(ctx, "mod", "count", count, "limit", limit, "mod", count%limit, "skipCount", skipCount)
+		// log.Info("limit plan", "date count", count, "limit", limit, "skipCount", skipCount)
+	}
+
+	toSkip := 0.0
+	if limit == 1 {
+		toSkip = skipCount // we just want to look for the last entry
+	}
+	lastDate := int64(0)
+	lastSkip := int64(0)
+	skipThreshold := 0.5
+	for _, c := range counts {
+		cDate := c.Date.Unix()
+		if (toSkip <= skipThreshold && cDate != lastSkip) ||
+			lastDate == cDate ||
+			mostRecentDate == cDate {
+			// log.Info("adding date", "date", c.Date.Format(time.DateOnly))
+			rv.History = append(rv.History, historyEntry{
+				D:  c.Date.Format(time.DateOnly),
+				Ts: int(cDate),
+				Ac: int(c.CountActive),
+				Rc: int(c.CountRegistered),
+				W:  int(c.NetspeedActive),
+				Iv: string(c.IpVersion),
+			})
+			lastDate = cDate
+		} else {
+			// log.Info("skipping date", "date", c.Date.Format(time.DateOnly))
+			if lastSkip == cDate {
+				continue
+			}
+			toSkip--
+			lastSkip = cDate
+			continue
+		}
+		if toSkip <= skipThreshold && skipCount > 0 {
+			toSkip += skipCount
+		}
+
+	}
+
+	if limit > 0 {
+		count := 0
+		dates := map[int]bool{}
+		for _, c := range rv.History {
+			ep := c.Ts
+			if _, ok := dates[ep]; !ok {
+				count++
+				dates[ep] = true
+			}
+		}
+		log.DebugContext(ctx, "result counts", "skipCount", skipCount, "limit", limit, "got", count)
+	}
+
+	c.Response().Header().Set("Cache-Control", "s-maxage=28800, max-age=7200")
+	return c.JSON(http.StatusOK, rv)
+
+}