expose System properties.

sdk/system.go

@@ -0,0 +1,54 @@
+package sdk
+
+import (
+	"context"
+	"time"
+
+	"github.com/nbd-wtf/go-nostr"
+	"github.com/nbd-wtf/go-nostr/sdk/cache"
+)
+
+type System struct {
+	RelaysCache      cache.Cache32[[]Relay]
+	FollowsCache     cache.Cache32[[]Follow]
+	MetadataCache    cache.Cache32[ProfileMetadata]
+	Pool             *nostr.SimplePool
+	RelayListRelays  []string
+	FollowListRelays []string
+	MetadataRelays   []string
+}
+
+func (sys System) FetchRelays(ctx context.Context, pubkey string) []Relay {
+	if v, ok := sys.RelaysCache.Get(pubkey); ok {
+		return v
+	}
+
+	ctx, cancel := context.WithTimeout(ctx, time.Second*5)
+	defer cancel()
+	res := FetchRelaysForPubkey(ctx, sys.Pool, pubkey, sys.RelayListRelays...)
+	sys.RelaysCache.SetWithTTL(pubkey, res, time.Hour*6)
+	return res
+}
+
+func (sys System) FetchOutboxRelays(ctx context.Context, pubkey string) []string {
+	relays := sys.FetchRelays(ctx, pubkey)
+	result := make([]string, 0, len(relays))
+	for _, relay := range relays {
+		if relay.Outbox {
+			result = append(result, relay.URL)
+		}
+	}
+	return result
+}
+
+func (sys System) FetchProfileMetadata(ctx context.Context, pubkey string) ProfileMetadata {
+	if v, ok := sys.MetadataCache.Get(pubkey); ok {
+		return v
+	}
+
+	ctx, cancel := context.WithTimeout(ctx, time.Second*5)
+	defer cancel()
+	res := FetchProfileMetadata(ctx, sys.Pool, pubkey, sys.MetadataRelays...)
+	sys.MetadataCache.SetWithTTL(pubkey, res, time.Hour*6)
+	return res
+}