From 9ce1ddfefe10debbddea84daa16263cb0a098e63 Mon Sep 17 00:00:00 2001
From: James Berry <james@coppermoth.com>
Date: Sun, 30 Mar 2025 11:04:17 +0100
Subject: [PATCH 1/3] Change cache ttl calculation for pokemon

---
 decoder/pokemon.go | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/decoder/pokemon.go b/decoder/pokemon.go
index 483e8653..93ceb80a 100644
--- a/decoder/pokemon.go
+++ b/decoder/pokemon.go
@@ -6,16 +6,17 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
 	"golbat/config"
 	"golbat/db"
 	"golbat/geo"
 	"golbat/grpc"
 	"golbat/pogo"
 	"golbat/webhooks"
-	"strconv"
-	"strings"
-	"sync"
-	"time"
 
 	"github.com/UnownHash/gohbem"
 	"github.com/golang/geo/s2"
@@ -539,11 +540,13 @@ func (pokemon *Pokemon) isNewRecord() bool {
 }
 
 func (pokemon *Pokemon) remainingDuration(now int64) time.Duration {
-	remaining := ttlcache.DefaultTTL
+	remaining := ttlcache.PreviousOrDefaultTTL
 	if pokemon.ExpireTimestampVerified {
 		timeLeft := 60 + pokemon.ExpireTimestamp.ValueOrZero() - now
-		if timeLeft > 1 {
+		if timeLeft > 60 {
 			remaining = time.Duration(timeLeft) * time.Second
+		} else {
+			remaining = time.Minute
 		}
 	}
 	return remaining

From 570e0820d138ce9c7532a9590b01e852193cb01a Mon Sep 17 00:00:00 2001
From: James Berry <james@coppermoth.com>
Date: Sun, 30 Mar 2025 11:09:42 +0100
Subject: [PATCH 2/3] Change cache ttl calculation for pokemon

---
 decoder/pokemon.go | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/decoder/pokemon.go b/decoder/pokemon.go
index 93ceb80a..9cf1c62d 100644
--- a/decoder/pokemon.go
+++ b/decoder/pokemon.go
@@ -161,7 +161,7 @@ func getPokemonRecord(ctx context.Context, db db.DbDetails, encounterId string)
 	}
 
 	if db.UsePokemonCache {
-		pokemonCache.Set(encounterId, pokemon, ttlcache.DefaultTTL)
+		pokemonCache.Set(encounterId, pokemon, pokemon.remainingDuration(time.Now().Unix()))
 	}
 	pokemonRtreeUpdatePokemonOnGet(&pokemon)
 	return &pokemon, nil
@@ -539,6 +539,9 @@ func (pokemon *Pokemon) isNewRecord() bool {
 	return pokemon.FirstSeenTimestamp == 0
 }
 
+// remainingDuration calculates a TTL for the pokemon cache based on known expiry
+// timestamp - with a minimum of 1 minute to allow the record to stay around and be queried
+// without rehydrating from the database post despawn
 func (pokemon *Pokemon) remainingDuration(now int64) time.Duration {
 	remaining := ttlcache.PreviousOrDefaultTTL
 	if pokemon.ExpireTimestampVerified {

From 9033c13138e8e7f0f8048a80182d7fc9cf325571 Mon Sep 17 00:00:00 2001
From: James Berry <james@coppermoth.com>
Date: Sun, 30 Mar 2025 15:11:57 +0100
Subject: [PATCH 3/3] Reduce cache ttl to 10 mins to cause expiry to happen
 more frequently, but boost cache time for initial pokemon record create/load

---
 decoder/main.go    | 2 +-
 decoder/pokemon.go | 8 ++++++--
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/decoder/main.go b/decoder/main.go
index 765d1849..482cfadd 100644
--- a/decoder/main.go
+++ b/decoder/main.go
@@ -126,7 +126,7 @@ func initDataCache() {
 	go spawnpointCache.Start()
 
 	pokemonCache = ttlcache.New[string, Pokemon](
-		ttlcache.WithTTL[string, Pokemon](60*time.Minute),
+		ttlcache.WithTTL[string, Pokemon](10*time.Minute),
 		ttlcache.WithDisableTouchOnHit[string, Pokemon](), // Pokemon will last 60 mins from when we first see them not last see them
 	)
 	go pokemonCache.Start()
diff --git a/decoder/pokemon.go b/decoder/pokemon.go
index 9cf1c62d..946a7a91 100644
--- a/decoder/pokemon.go
+++ b/decoder/pokemon.go
@@ -161,7 +161,11 @@ func getPokemonRecord(ctx context.Context, db db.DbDetails, encounterId string)
 	}
 
 	if db.UsePokemonCache {
-		pokemonCache.Set(encounterId, pokemon, pokemon.remainingDuration(time.Now().Unix()))
+		remainingDuration := pokemon.remainingDuration(time.Now().Unix())
+		if remainingDuration <= 0 { // DefaultTTL or PreviousDefaultTTL gives us an hour (longer than ttlcache default)
+			remainingDuration = time.Hour
+		}
+		pokemonCache.Set(encounterId, pokemon, remainingDuration)
 	}
 	pokemonRtreeUpdatePokemonOnGet(&pokemon)
 	return &pokemon, nil
@@ -174,7 +178,7 @@ func getOrCreatePokemonRecord(ctx context.Context, db db.DbDetails, encounterId
 	}
 	pokemon = &Pokemon{Id: encounterId}
 	if db.UsePokemonCache {
-		pokemonCache.Set(encounterId, *pokemon, ttlcache.DefaultTTL)
+		pokemonCache.Set(encounterId, *pokemon, time.Hour) // create new record with an hour TTL initially
 	}
 	return pokemon, nil
 }