Merge pull request #33 from syncthing/negcache

Set Retry-After header
This commit is contained in:
Audrius Butkevicius 2015-12-01 09:58:20 +00:00
commit 55da600433
4 changed files with 51 additions and 2 deletions

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@ -14,6 +14,12 @@ import (
"github.com/thejerf/suture" "github.com/thejerf/suture"
) )
const (
minNegCache = 60 // seconds
maxNegCache = 3600 // seconds
maxDeviceAge = 7 * 86400 // one week, in seconds
)
var ( var (
lruSize = 10240 lruSize = 10240
limitAvg = 5 limitAvg = 5

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@ -4,6 +4,7 @@ package main
import ( import (
"database/sql" "database/sql"
"fmt"
_ "github.com/lib/pq" _ "github.com/lib/pq"
) )
@ -100,7 +101,7 @@ func postgresCompile(db *sql.DB) (map[string]*sql.Stmt, error) {
stmts := map[string]string{ stmts := map[string]string{
"cleanAddress": "DELETE FROM Addresses WHERE Seen < now() - '2 hour'::INTERVAL", "cleanAddress": "DELETE FROM Addresses WHERE Seen < now() - '2 hour'::INTERVAL",
"cleanRelay": "DELETE FROM Relays WHERE Seen < now() - '2 hour'::INTERVAL", "cleanRelay": "DELETE FROM Relays WHERE Seen < now() - '2 hour'::INTERVAL",
"cleanDevice": "DELETE FROM Devices WHERE Seen < now() - '24 hour'::INTERVAL", "cleanDevice": fmt.Sprintf("DELETE FROM Devices WHERE Seen < now() - '%d hour'::INTERVAL", maxDeviceAge/3600),
"countAddress": "SELECT count(*) FROM Addresses", "countAddress": "SELECT count(*) FROM Addresses",
"countDevice": "SELECT count(*) FROM Devices", "countDevice": "SELECT count(*) FROM Devices",
"countRelay": "SELECT count(*) FROM Relays", "countRelay": "SELECT count(*) FROM Relays",
@ -109,6 +110,7 @@ func postgresCompile(db *sql.DB) (map[string]*sql.Stmt, error) {
"insertDevice": "INSERT INTO Devices (DeviceID, Seen) VALUES ($1, now())", "insertDevice": "INSERT INTO Devices (DeviceID, Seen) VALUES ($1, now())",
"selectAddress": "SELECT Address FROM Addresses WHERE DeviceID=$1 AND Seen > now() - '1 hour'::INTERVAL ORDER BY random() LIMIT 16", "selectAddress": "SELECT Address FROM Addresses WHERE DeviceID=$1 AND Seen > now() - '1 hour'::INTERVAL ORDER BY random() LIMIT 16",
"selectRelay": "SELECT Address, Latency FROM Relays WHERE DeviceID=$1 AND Seen > now() - '1 hour'::INTERVAL ORDER BY random() LIMIT 16", "selectRelay": "SELECT Address, Latency FROM Relays WHERE DeviceID=$1 AND Seen > now() - '1 hour'::INTERVAL ORDER BY random() LIMIT 16",
"selectDevice": "SELECT Seen FROM Devices WHERE DeviceID=$1",
"updateAddress": "UPDATE Addresses SET Seen=now() WHERE DeviceID=$1 AND Address=$2", "updateAddress": "UPDATE Addresses SET Seen=now() WHERE DeviceID=$1 AND Address=$2",
"updateDevice": "UPDATE Devices SET Seen=now() WHERE DeviceID=$1", "updateDevice": "UPDATE Devices SET Seen=now() WHERE DeviceID=$1",
"deleteRelay": "DELETE FROM Relays WHERE DeviceID=$1", "deleteRelay": "DELETE FROM Relays WHERE DeviceID=$1",

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@ -4,6 +4,7 @@ package main
import ( import (
"database/sql" "database/sql"
"fmt"
"log" "log"
"github.com/cznic/ql" "github.com/cznic/ql"
@ -71,7 +72,7 @@ func qlCompile(db *sql.DB) (map[string]*sql.Stmt, error) {
stmts := map[string]string{ stmts := map[string]string{
"cleanAddress": `DELETE FROM Addresses WHERE Seen < now() - duration("2h")`, "cleanAddress": `DELETE FROM Addresses WHERE Seen < now() - duration("2h")`,
"cleanRelay": `DELETE FROM Relays WHERE Seen < now() - duration("2h")`, "cleanRelay": `DELETE FROM Relays WHERE Seen < now() - duration("2h")`,
"cleanDevice": `DELETE FROM Devices WHERE Seen < now() - duration("24h")`, "cleanDevice": fmt.Sprintf(`DELETE FROM Devices WHERE Seen < now() - duration("%dh")`, maxDeviceAge/3600),
"countAddress": "SELECT count(*) FROM Addresses", "countAddress": "SELECT count(*) FROM Addresses",
"countDevice": "SELECT count(*) FROM Devices", "countDevice": "SELECT count(*) FROM Devices",
"countRelay": "SELECT count(*) FROM Relays", "countRelay": "SELECT count(*) FROM Relays",
@ -80,6 +81,7 @@ func qlCompile(db *sql.DB) (map[string]*sql.Stmt, error) {
"insertDevice": "INSERT INTO Devices (DeviceID, Seen) VALUES ($1, now())", "insertDevice": "INSERT INTO Devices (DeviceID, Seen) VALUES ($1, now())",
"selectAddress": `SELECT Address from Addresses WHERE DeviceID==$1 AND Seen > now() - duration("1h") LIMIT 16`, "selectAddress": `SELECT Address from Addresses WHERE DeviceID==$1 AND Seen > now() - duration("1h") LIMIT 16`,
"selectRelay": `SELECT Address, Latency from Relays WHERE DeviceID==$1 AND Seen > now() - duration("1h") LIMIT 16`, "selectRelay": `SELECT Address, Latency from Relays WHERE DeviceID==$1 AND Seen > now() - duration("1h") LIMIT 16`,
"selectDevice": "SELECT Seen FROM Devices WHERE DeviceID==$1",
"updateAddress": "UPDATE Addresses Seen=now() WHERE DeviceID==$1 AND Address==$2", "updateAddress": "UPDATE Addresses Seen=now() WHERE DeviceID==$1 AND Address==$2",
"updateDevice": "UPDATE Devices Seen=now() WHERE DeviceID==$1", "updateDevice": "UPDATE Devices Seen=now() WHERE DeviceID==$1",
"deleteRelay": "DELETE FROM Relays WHERE DeviceID==$1", "deleteRelay": "DELETE FROM Relays WHERE DeviceID==$1",

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@ -12,6 +12,7 @@ import (
"net" "net"
"net/http" "net/http"
"net/url" "net/url"
"strconv"
"sync" "sync"
"time" "time"
@ -30,6 +31,7 @@ type querysrv struct {
} }
type announcement struct { type announcement struct {
Seen time.Time
Direct []string `json:"direct"` Direct []string `json:"direct"`
Relays []annRelay `json:"relays"` Relays []annRelay `json:"relays"`
} }
@ -57,6 +59,22 @@ func (s *safeCache) Add(key string, val interface{}) {
s.mut.Unlock() s.mut.Unlock()
} }
func negCacheFor(lastSeen time.Time) int {
since := time.Since(lastSeen).Seconds()
if since >= maxDeviceAge {
return maxNegCache
}
if since < 0 {
// That's weird
return minNegCache
}
// Return a value linearly scaled from minNegCache (at zero seconds ago)
// to maxNegCache (at maxDeviceAge seconds ago).
r := since / maxDeviceAge
return int(minNegCache + r*(maxNegCache-minNegCache))
}
func (s *querysrv) Serve() { func (s *querysrv) Serve() {
s.limiter = &safeCache{ s.limiter = &safeCache{
Cache: lru.New(lruSize), Cache: lru.New(lruSize),
@ -158,6 +176,18 @@ func (s *querysrv) handleGET(w http.ResponseWriter, req *http.Request) {
var ann announcement var ann announcement
ann.Seen, err = s.getDeviceSeen(deviceID)
negCache := strconv.Itoa(negCacheFor(ann.Seen))
w.Header().Set("Retry-After", negCache)
w.Header().Set("Cache-Control", "public, max-age="+negCache)
if err != nil {
// The device is not in the database.
globalStats.Query()
http.Error(w, "Not Found", http.StatusNotFound)
return
}
ann.Direct, err = s.getAddresses(deviceID) ann.Direct, err = s.getAddresses(deviceID)
if err != nil { if err != nil {
log.Println("getAddresses:", err) log.Println("getAddresses:", err)
@ -385,6 +415,15 @@ func (s *querysrv) getAddresses(device protocol.DeviceID) ([]string, error) {
return res, nil return res, nil
} }
func (s *querysrv) getDeviceSeen(device protocol.DeviceID) (time.Time, error) {
row := s.prep["selectDevice"].QueryRow(device.String())
var seen time.Time
if err := row.Scan(&seen); err != nil {
return time.Time{}, err
}
return seen, nil
}
func (s *querysrv) getRelays(device protocol.DeviceID) ([]annRelay, error) { func (s *querysrv) getRelays(device protocol.DeviceID) ([]annRelay, error) {
rows, err := s.prep["selectRelay"].Query(device.String()) rows, err := s.prep["selectRelay"].Query(device.String())
if err != nil { if err != nil {