added LRU caching and communities data

database/community.go

@@ -0,0 +1,77 @@
+/*
+ * Amsterdam Web Communities System
+ * Copyright (c) 2025 Erbosoft Metaverse Design Solutions, All Rights Reserved
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+// The database package contains database management and storage logic.
+package database
+
+import (
+	"fmt"
+	"time"
+
+	lru "github.com/hashicorp/golang-lru"
+)
+
+// Community struct contains the high level data for a community.
+type Community struct {
+	Id                int32      `db:"commid"`
+	CreateDate        time.Time  `db:"createdate"`
+	LastAccess        *time.Time `db:"lastaccess"`
+	LastUpdate        *time.Time `db:"lastupdate"`
+	ReadLevel         uint16     `db:"read_lvl"`
+	WriteLevel        uint16     `db:"write_lvl"`
+	CreateLevel       uint16     `db:"create_lvl"`
+	JoinLevel         uint16     `db:"join_lvl"`
+	ContactId         int32      `db:"contactid"`
+	HostUid           *int32     `db:"host_uid"`
+	CategoryId        int32      `db:"catid"`
+	HideFromDirectory bool       `db:"hide_dir"`
+	HideFromSearch    bool       `db:"hide_search"`
+	MembersOnly       bool       `db:"membersonly"`
+	IsAdmin           bool       `db:"is_admin"`
+	InitFeature       int16      `db:"init_ftr"`
+	Name              string     `db:"commname"`
+	Language          *string    `db:"language"`
+	Synopsis          *string    `db:"synopsis"`
+	Rules             *string    `dd:"rules"`
+	JoinKey           *string    `db:"joinkey"`
+	Alias             string     `db:"alias"`
+}
+
+// communityCache is the cache for Community objects.
+var communityCache *lru.TwoQueueCache = nil
+
+/* AmGetCommunity returns a reference to the specified community.
+ * Parameters:
+ *     id - The ID of the community.
+ * Returns:
+ *     Pointer to Community containing community data, or nil
+ *     Standard Go error status
+ */
+func AmGetCommunity(id int32) (*Community, error) {
+	var err error = nil
+	if communityCache == nil {
+		communityCache, err = lru.New2Q(50)
+		if err != nil {
+			return nil, err
+		}
+	}
+	rc, ok := communityCache.Get(id)
+	if !ok {
+		var dbdata []Community
+		err = amdb.Select(&dbdata, "SELECT * from communities WHERE commid = ?", id)
+		if err != nil {
+			return nil, err
+		}
+		if len(dbdata) > 1 {
+			return nil, fmt.Errorf("AmGetCommunity(%d): too many responses(%d)", id, len(dbdata))
+		}
+		rc = &(dbdata[0])
+		communityCache.Add(id, rc)
+	}
+	return rc.(*Community), err
+}