tile38/internal/server/search.go
tidwall 9e68703841 Update expiration logic
This commit changes the logic for managing the expiration of
objects in the database.

Before: There was a server-wide hashmap that stored the
collection key, id, and expiration timestamp for all objects
that had a TTL. The hashmap was occasionally probed at 20
random positions, looking for objects that have expired. Those
expired objects were immediately deleted, and if there was 5
or more objects deleted, then the probe happened again, with
no delay. If the number of objects was less than 5 then the
there was a 1/10th of a second delay before the next probe.

Now: Rather than a server-wide hashmap, each collection has
its own ordered priority queue that stores objects with TTLs.
Rather than probing, there is a background routine that
executes every 1/10th of a second, which pops the expired
objects from the collection queues, and deletes them.

The collection/queue method is a more stable approach than
the hashmap/probing method. With probing, we can run into
major cache misses for some cases where there is wide
TTL duration, such as in the hours or days. This may cause
the system to occasionally fall behind, leaving should-be
expired objects in memory. Using a queue, there is no
cache misses, all objects that should be expired will be
right away, regardless of the TTL durations.

Fixes #616
2021-07-12 13:37:50 -07:00

619 lines
15 KiB
Go

package server
import (
"bytes"
"errors"
"strconv"
"strings"
"time"
"github.com/mmcloughlin/geohash"
"github.com/tidwall/geojson"
"github.com/tidwall/geojson/geometry"
"github.com/tidwall/resp"
"github.com/tidwall/tile38/internal/bing"
"github.com/tidwall/tile38/internal/clip"
"github.com/tidwall/tile38/internal/glob"
)
const defaultCircleSteps = 64
type liveFenceSwitches struct {
searchScanBaseTokens
obj geojson.Object
cmd string
roam roamSwitches
groups map[string]string
}
type roamSwitches struct {
on bool
key string
id string
pattern bool
meters float64
scan string
}
type roamMatch struct {
id string
obj geojson.Object
meters float64
}
func (s liveFenceSwitches) Error() string {
return goingLive
}
func (s liveFenceSwitches) Close() {
for _, whereeval := range s.whereevals {
whereeval.Close()
}
}
func (s liveFenceSwitches) usingLua() bool {
return len(s.whereevals) > 0
}
func parseRectArea(ltyp string, vs []string) (nvs []string, rect *geojson.Rect, err error) {
var ok bool
switch ltyp {
default:
err = errNotRectangle
return
case "bounds":
var sminLat, sminLon, smaxlat, smaxlon string
if vs, sminLat, ok = tokenval(vs); !ok || sminLat == "" {
err = errInvalidNumberOfArguments
return
}
if vs, sminLon, ok = tokenval(vs); !ok || sminLon == "" {
err = errInvalidNumberOfArguments
return
}
if vs, smaxlat, ok = tokenval(vs); !ok || smaxlat == "" {
err = errInvalidNumberOfArguments
return
}
if vs, smaxlon, ok = tokenval(vs); !ok || smaxlon == "" {
err = errInvalidNumberOfArguments
return
}
var minLat, minLon, maxLat, maxLon float64
if minLat, err = strconv.ParseFloat(sminLat, 64); err != nil {
err = errInvalidArgument(sminLat)
return
}
if minLon, err = strconv.ParseFloat(sminLon, 64); err != nil {
err = errInvalidArgument(sminLon)
return
}
if maxLat, err = strconv.ParseFloat(smaxlat, 64); err != nil {
err = errInvalidArgument(smaxlat)
return
}
if maxLon, err = strconv.ParseFloat(smaxlon, 64); err != nil {
err = errInvalidArgument(smaxlon)
return
}
rect = geojson.NewRect(geometry.Rect{
Min: geometry.Point{X: minLon, Y: minLat},
Max: geometry.Point{X: maxLon, Y: maxLat},
})
case "hash":
var hash string
if vs, hash, ok = tokenval(vs); !ok || hash == "" {
err = errInvalidNumberOfArguments
return
}
box := geohash.BoundingBox(hash)
rect = geojson.NewRect(geometry.Rect{
Min: geometry.Point{X: box.MinLng, Y: box.MinLat},
Max: geometry.Point{X: box.MaxLng, Y: box.MaxLat},
})
case "quadkey":
var key string
if vs, key, ok = tokenval(vs); !ok || key == "" {
err = errInvalidNumberOfArguments
return
}
var minLat, minLon, maxLat, maxLon float64
minLat, minLon, maxLat, maxLon, err = bing.QuadKeyToBounds(key)
if err != nil {
err = errInvalidArgument(key)
return
}
rect = geojson.NewRect(geometry.Rect{
Min: geometry.Point{X: minLon, Y: minLat},
Max: geometry.Point{X: maxLon, Y: maxLat},
})
case "tile":
var sx, sy, sz string
if vs, sx, ok = tokenval(vs); !ok || sx == "" {
err = errInvalidNumberOfArguments
return
}
if vs, sy, ok = tokenval(vs); !ok || sy == "" {
err = errInvalidNumberOfArguments
return
}
if vs, sz, ok = tokenval(vs); !ok || sz == "" {
err = errInvalidNumberOfArguments
return
}
var x, y int64
var z uint64
if x, err = strconv.ParseInt(sx, 10, 64); err != nil {
err = errInvalidArgument(sx)
return
}
if y, err = strconv.ParseInt(sy, 10, 64); err != nil {
err = errInvalidArgument(sy)
return
}
if z, err = strconv.ParseUint(sz, 10, 64); err != nil {
err = errInvalidArgument(sz)
return
}
var minLat, minLon, maxLat, maxLon float64
minLat, minLon, maxLat, maxLon = bing.TileXYToBounds(x, y, z)
rect = geojson.NewRect(geometry.Rect{
Min: geometry.Point{X: minLon, Y: minLat},
Max: geometry.Point{X: maxLon, Y: maxLat},
})
}
nvs = vs
return
}
func (server *Server) cmdSearchArgs(
fromFenceCmd bool, cmd string, vs []string, types []string,
) (s liveFenceSwitches, err error) {
var t searchScanBaseTokens
if fromFenceCmd {
t.fence = true
}
vs, t, err = server.parseSearchScanBaseTokens(cmd, t, vs)
if err != nil {
return
}
s.searchScanBaseTokens = t
var typ string
var ok bool
if vs, typ, ok = tokenval(vs); !ok || typ == "" {
err = errInvalidNumberOfArguments
return
}
if s.searchScanBaseTokens.output == outputBounds {
if cmd == "within" || cmd == "intersects" {
if _, err := strconv.ParseFloat(typ, 64); err == nil {
// It's likely that the output was not specified, but rather the search bounds.
s.searchScanBaseTokens.output = defaultSearchOutput
vs = append([]string{typ}, vs...)
typ = "BOUNDS"
}
}
}
ltyp := strings.ToLower(typ)
var found bool
for _, t := range types {
if ltyp == t {
found = true
break
}
}
if !found && s.searchScanBaseTokens.fence && ltyp == "roam" && cmd == "nearby" {
// allow roaming for nearby fence searches.
found = true
}
if !found {
err = errInvalidArgument(typ)
return
}
switch ltyp {
case "point":
fallthrough
case "circle":
if s.clip {
err = errInvalidArgument("cannot clip with " + ltyp)
return
}
var slat, slon, smeters string
if vs, slat, ok = tokenval(vs); !ok || slat == "" {
err = errInvalidNumberOfArguments
return
}
if vs, slon, ok = tokenval(vs); !ok || slon == "" {
err = errInvalidNumberOfArguments
return
}
var lat, lon, meters float64
if lat, err = strconv.ParseFloat(slat, 64); err != nil {
err = errInvalidArgument(slat)
return
}
if lon, err = strconv.ParseFloat(slon, 64); err != nil {
err = errInvalidArgument(slon)
return
}
// radius is optional for nearby, but mandatory for others
if cmd == "nearby" {
if vs, smeters, ok = tokenval(vs); ok && smeters != "" {
if meters, err = strconv.ParseFloat(smeters, 64); err != nil {
err = errInvalidArgument(smeters)
return
}
if meters < 0 {
err = errInvalidArgument(smeters)
return
}
} else {
meters = -1
}
} else {
if vs, smeters, ok = tokenval(vs); !ok || smeters == "" {
err = errInvalidNumberOfArguments
return
}
if meters, err = strconv.ParseFloat(smeters, 64); err != nil {
err = errInvalidArgument(smeters)
return
}
if meters < 0 {
err = errInvalidArgument(smeters)
return
}
}
s.obj = geojson.NewCircle(geometry.Point{X: lon, Y: lat}, meters, defaultCircleSteps)
case "object":
if s.clip {
err = errInvalidArgument("cannot clip with object")
return
}
var obj string
if vs, obj, ok = tokenval(vs); !ok || obj == "" {
err = errInvalidNumberOfArguments
return
}
s.obj, err = geojson.Parse(obj, &server.geomParseOpts)
if err != nil {
return
}
case "bounds", "hash", "tile", "quadkey":
vs, s.obj, err = parseRectArea(ltyp, vs)
if err != nil {
return
}
case "get":
if s.clip {
err = errInvalidArgument("cannot clip with get")
}
var key, id string
if vs, key, ok = tokenval(vs); !ok || key == "" {
err = errInvalidNumberOfArguments
return
}
if vs, id, ok = tokenval(vs); !ok || id == "" {
err = errInvalidNumberOfArguments
return
}
col := server.getCol(key)
if col == nil {
err = errKeyNotFound
return
}
s.obj, _, _, ok = col.Get(id)
if !ok {
err = errIDNotFound
return
}
case "roam":
s.roam.on = true
if vs, s.roam.key, ok = tokenval(vs); !ok || s.roam.key == "" {
err = errInvalidNumberOfArguments
return
}
if vs, s.roam.id, ok = tokenval(vs); !ok || s.roam.id == "" {
err = errInvalidNumberOfArguments
return
}
s.roam.pattern = glob.IsGlob(s.roam.id)
var smeters string
if vs, smeters, ok = tokenval(vs); !ok || smeters == "" {
err = errInvalidNumberOfArguments
return
}
if s.roam.meters, err = strconv.ParseFloat(smeters, 64); err != nil {
err = errInvalidArgument(smeters)
return
}
var scan string
if vs, scan, ok = tokenval(vs); ok {
if strings.ToLower(scan) != "scan" {
err = errInvalidArgument(scan)
return
}
if vs, scan, ok = tokenval(vs); !ok || scan == "" {
err = errInvalidNumberOfArguments
return
}
s.roam.scan = scan
}
}
var clip_rect *geojson.Rect
var tok, ltok string
for len(vs) > 0 {
if vs, tok, ok = tokenval(vs); !ok || tok == "" {
err = errInvalidNumberOfArguments
return
}
if strings.ToLower(tok) != "clipby" {
err = errInvalidNumberOfArguments
return
}
if vs, tok, ok = tokenval(vs); !ok || tok == "" {
err = errInvalidNumberOfArguments
return
}
ltok = strings.ToLower(tok)
switch ltok {
case "bounds", "hash", "tile", "quadkey":
vs, clip_rect, err = parseRectArea(ltok, vs)
if err == errNotRectangle {
err = errInvalidArgument("cannot clipby " + ltok)
return
}
if err != nil {
return
}
s.obj = clip.Clip(s.obj, clip_rect, &server.geomIndexOpts)
default:
err = errInvalidArgument("cannot clipby " + ltok)
return
}
}
return
}
var nearbyTypes = []string{"point"}
var withinOrIntersectsTypes = []string{
"geo", "bounds", "hash", "tile", "quadkey", "get", "object", "circle"}
func (server *Server) cmdNearby(msg *Message) (res resp.Value, err error) {
start := time.Now()
vs := msg.Args[1:]
wr := &bytes.Buffer{}
s, err := server.cmdSearchArgs(false, "nearby", vs, nearbyTypes)
if s.usingLua() {
defer s.Close()
defer func() {
if r := recover(); r != nil {
res = NOMessage
err = errors.New(r.(string))
return
}
}()
}
if err != nil {
return NOMessage, err
}
s.cmd = "nearby"
if s.fence {
return NOMessage, s
}
sw, err := server.newScanWriter(
wr, msg, s.key, s.output, s.precision, s.glob, false,
s.cursor, s.limit, s.wheres, s.whereins, s.whereevals, s.nofields)
if err != nil {
return NOMessage, err
}
if msg.OutputType == JSON {
wr.WriteString(`{"ok":true`)
}
sw.writeHead()
if sw.col != nil {
maxDist := s.obj.(*geojson.Circle).Meters()
iter := func(id string, o geojson.Object, fields []float64, dist float64) bool {
if maxDist > 0 && dist > maxDist {
return false
}
meters := 0.0
if s.distance {
meters = dist
}
return sw.writeObject(ScanWriterParams{
id: id,
o: o,
fields: fields,
distance: meters,
distOutput: s.distance,
noLock: true,
ignoreGlobMatch: true,
skipTesting: true,
})
}
sw.col.Nearby(s.obj, sw, msg.Deadline, iter)
}
sw.writeFoot()
if msg.OutputType == JSON {
wr.WriteString(`,"elapsed":"` + time.Since(start).String() + "\"}")
return resp.BytesValue(wr.Bytes()), nil
}
return sw.respOut, nil
}
func (server *Server) cmdWithin(msg *Message) (res resp.Value, err error) {
return server.cmdWithinOrIntersects("within", msg)
}
func (server *Server) cmdIntersects(msg *Message) (res resp.Value, err error) {
return server.cmdWithinOrIntersects("intersects", msg)
}
func (server *Server) cmdWithinOrIntersects(cmd string, msg *Message) (res resp.Value, err error) {
start := time.Now()
vs := msg.Args[1:]
wr := &bytes.Buffer{}
s, err := server.cmdSearchArgs(false, cmd, vs, withinOrIntersectsTypes)
if s.usingLua() {
defer s.Close()
defer func() {
if r := recover(); r != nil {
res = NOMessage
err = errors.New(r.(string))
return
}
}()
}
if err != nil {
return NOMessage, err
}
s.cmd = cmd
if s.fence {
return NOMessage, s
}
sw, err := server.newScanWriter(
wr, msg, s.key, s.output, s.precision, s.glob, false,
s.cursor, s.limit, s.wheres, s.whereins, s.whereevals, s.nofields)
if err != nil {
return NOMessage, err
}
if msg.OutputType == JSON {
wr.WriteString(`{"ok":true`)
}
sw.writeHead()
if sw.col != nil {
if cmd == "within" {
sw.col.Within(s.obj, s.sparse, sw, msg.Deadline, func(
id string, o geojson.Object, fields []float64,
) bool {
return sw.writeObject(ScanWriterParams{
id: id,
o: o,
fields: fields,
noLock: true,
})
})
} else if cmd == "intersects" {
sw.col.Intersects(s.obj, s.sparse, sw, msg.Deadline, func(
id string,
o geojson.Object,
fields []float64,
) bool {
params := ScanWriterParams{
id: id,
o: o,
fields: fields,
noLock: true,
}
if s.clip {
params.clip = s.obj
}
return sw.writeObject(params)
})
}
}
sw.writeFoot()
if msg.OutputType == JSON {
wr.WriteString(`,"elapsed":"` + time.Since(start).String() + "\"}")
return resp.BytesValue(wr.Bytes()), nil
}
return sw.respOut, nil
}
func (server *Server) cmdSeachValuesArgs(vs []string) (
s liveFenceSwitches, err error,
) {
var t searchScanBaseTokens
vs, t, err = server.parseSearchScanBaseTokens("search", t, vs)
if err != nil {
return
}
s.searchScanBaseTokens = t
if len(vs) != 0 {
err = errInvalidNumberOfArguments
return
}
return
}
func (server *Server) cmdSearch(msg *Message) (res resp.Value, err error) {
start := time.Now()
vs := msg.Args[1:]
wr := &bytes.Buffer{}
s, err := server.cmdSeachValuesArgs(vs)
if s.usingLua() {
defer s.Close()
defer func() {
if r := recover(); r != nil {
res = NOMessage
err = errors.New(r.(string))
return
}
}()
}
if err != nil {
return NOMessage, err
}
sw, err := server.newScanWriter(
wr, msg, s.key, s.output, s.precision, s.glob, true,
s.cursor, s.limit, s.wheres, s.whereins, s.whereevals, s.nofields)
if err != nil {
return NOMessage, err
}
if msg.OutputType == JSON {
wr.WriteString(`{"ok":true`)
}
sw.writeHead()
if sw.col != nil {
if sw.output == outputCount && len(sw.wheres) == 0 && sw.globEverything {
count := sw.col.Count() - int(s.cursor)
if count < 0 {
count = 0
}
sw.count = uint64(count)
} else {
g := glob.Parse(sw.globPattern, s.desc)
if g.Limits[0] == "" && g.Limits[1] == "" {
sw.col.SearchValues(s.desc, sw, msg.Deadline,
func(id string, o geojson.Object, fields []float64) bool {
return sw.writeObject(ScanWriterParams{
id: id,
o: o,
fields: fields,
noLock: true,
})
},
)
} else {
// must disable globSingle for string value type matching because
// globSingle is only for ID matches, not values.
sw.globSingle = false
sw.col.SearchValuesRange(g.Limits[0], g.Limits[1], s.desc, sw,
msg.Deadline,
func(id string, o geojson.Object, fields []float64) bool {
return sw.writeObject(ScanWriterParams{
id: id,
o: o,
fields: fields,
noLock: true,
})
},
)
}
}
}
sw.writeFoot()
if msg.OutputType == JSON {
wr.WriteString(`,"elapsed":"` + time.Since(start).String() + "\"}")
return resp.BytesValue(wr.Bytes()), nil
}
return sw.respOut, nil
}