ModernUO/Projects/UOContent/Engines
Kamron Batman b191498569
feat: Adds Feature Flag System (#2328)
## Feature Flag System

A runtime feature flag system for dynamically enabling/disabling game systems and blocking specific game elements
without server restarts.

### Overview

Two types of controls:

1. Feature Flags - Named boolean flags that gate entire systems (trading, PvP, vendors, housing, etc.)
2. Dynamic Blocks - Block specific gumps, items, skills, or spells by type

All changes are persisted to JSON, broadcast to online staff, and bypass-able by administrators.

### Predefined Flags
```
┌─────────────────┬──────────┬─────────────────────────────────────┐
│      Flag       │ Category │             Description             │
├─────────────────┼──────────┼─────────────────────────────────────┤
│ player_trading  │ Economy  │ Allow secure trades between players │
├─────────────────┼──────────┼─────────────────────────────────────┤
│ vendor_purchase │ Economy  │ Allow purchasing from NPC vendors   │
├─────────────────┼──────────┼─────────────────────────────────────┤
│ vendor_sell     │ Economy  │ Allow selling to NPC vendors        │
├─────────────────┼──────────┼─────────────────────────────────────┤
│ player_vendors  │ Economy  │ Allow player vendor interactions    │
├─────────────────┼──────────┼─────────────────────────────────────┤
│ bank_access     │ Economy  │ Allow bank box access               │
├─────────────────┼──────────┼─────────────────────────────────────┤
│ house_placement │ Housing  │ Allow new house placements          │
├─────────────────┼──────────┼─────────────────────────────────────┤
│ boat_placement  │ Housing  │ Allow new boat placements           │
├─────────────────┼──────────┼─────────────────────────────────────┤
│ bulk_orders     │ Crafting │ Allow bulk order deeds              │
├─────────────────┼──────────┼─────────────────────────────────────┤
│ pvp_combat      │ Combat   │ Allow player vs player combat       │
└─────────────────┴──────────┴─────────────────────────────────────┘
```

### Commands

#### Feature Flags
```
┌────────────────────────────────────────────────────┬───────────────────────┐
│                      Command                       │      Description      │
├────────────────────────────────────────────────────┼───────────────────────┤
│ [FeatureFlag <key> on|off|toggle|info              │ Manage a feature flag │
├────────────────────────────────────────────────────┼───────────────────────┤
│ [FF <key> on|off                                   │ Shorthand alias       │
├────────────────────────────────────────────────────┼───────────────────────┤
│ [FeatureFlag <key> create <category> <desc>        │ Create a custom flag  │
├────────────────────────────────────────────────────┼───────────────────────┤
│ [FeatureFlag <key> delete                          │ Delete a custom flag  │
├────────────────────────────────────────────────────┼───────────────────────┤
│ [FeatureList [flags|gumps|items|skills|spells|all] │ List all flags/blocks │
├────────────────────────────────────────────────────┼───────────────────────┤
│ [FeatureAdmin                                      │ Open the admin gump   │
└────────────────────────────────────────────────────┴───────────────────────┘
```

#### Gump Blocks
```
┌────────────────────────────────┬──────────────────────────────────────────────────────┐
│            Command             │                     Description                      │
├────────────────────────────────┼──────────────────────────────────────────────────────┤
│ [BlockGump <typeName> [reason] │ Block a gump type from displaying                    │
├────────────────────────────────┼──────────────────────────────────────────────────────┤
│ [UnblockGump <typeName>        │ Remove a gump block                                  │
├────────────────────────────────┼──────────────────────────────────────────────────────┤
│ [ListGumps [self]              │ List open gumps on a player (for finding type names) │
└────────────────────────────────┴──────────────────────────────────────────────────────┘
```

#### Item Blocks
```
┌────────────────────────────────────────────────┬───────────────────────────────┐
│                    Command                     │          Description          │
├────────────────────────────────────────────────┼───────────────────────────────┤
│ [BlockItemUse <typeName|target> [reason]       │ Block item use                │
├────────────────────────────────────────────────┼───────────────────────────────┤
│ [BlockItemEquip <typeName|target> [reason]     │ Block item equipping          │
├────────────────────────────────────────────────┼───────────────────────────────┤
│ [BlockItemContainer <typeName|target> [reason] │ Block container access        │
├────────────────────────────────────────────────┼───────────────────────────────┤
│ [UnblockItemUse <typeName>                     │ Remove use block              │
├────────────────────────────────────────────────┼───────────────────────────────┤
│ [UnblockItemEquip <typeName>                   │ Remove equip block            │
├────────────────────────────────────────────────┼───────────────────────────────┤
│ [UnblockItemContainer <typeName>               │ Remove container access block │
└────────────────────────────────────────────────┴───────────────────────────────┘
```
Item block commands create an entry if one doesn't exist, or flip the relevant flag on an existing entry. Unblock
commands only clear their specific flag -- the entry is removed when all flags (use/equip/container) are off.

#### Skill & Spell Blocks
```
┌──────────────────────────────────────┬──────────────────────┐
│               Command                │     Description      │
├──────────────────────────────────────┼──────────────────────┤
│ [BlockSkill <SkillName> [reason]     │ Block a skill        │
├──────────────────────────────────────┼──────────────────────┤
│ [UnblockSkill <SkillName>            │ Remove a skill block │
├──────────────────────────────────────┼──────────────────────┤
│ [BlockSpell <SpellTypeName> [reason] │ Block a spell        │
├──────────────────────────────────────┼──────────────────────┤
│ [UnblockSpell <SpellTypeName>        │ Remove a spell block │
└──────────────────────────────────────┴──────────────────────┘
```

### Architecture

- Static bool classes for hot-path checks (no dictionary lookups): ServerFeatureFlags (Server project) and
ContentFeatureFlags (UOContent)
- Synced automatically by FeatureFlagManager.SyncStaticFlag() when flags change
- Predefined flags loaded from Distribution/Configuration/FeatureFlags/default-flags.json
- Runtime state persisted to Configuration/FeatureFlags/*.json (flags, gump-blocks, item-blocks, skill-blocks,
spell-blocks)
- Admin gump with tabbed UI for managing all block types, per-entry PropertiesGump editing, and pagination
- All staff at AccessLevel.GameMaster+ bypass dynamic blocks; AccessLevel.Administrator+ bypass feature flags

### Hook Points

Hook: Player trading
Location: Mobile.OpenTrade
Mechanism: ServerFeatureFlags.PlayerTrading
────────────────────────────────────────
Hook: PvP combat
Location: Mobile.CanBeHarmful
Mechanism: ServerFeatureFlags.PvPCombat
────────────────────────────────────────
Hook: Bank access
Location: BankBox.Open()
Mechanism: ServerFeatureFlags.BankAccess
────────────────────────────────────────
Hook: Vendor buy/sell
Location: BaseVendor
Mechanism: ContentFeatureFlags.VendorPurchase/Sell
────────────────────────────────────────
Hook: Player vendors
Location: PlayerVendor
Mechanism: ContentFeatureFlags.PlayerVendors
────────────────────────────────────────
Hook: House placement
Location: HousePlacement.Check()
Mechanism: ContentFeatureFlags.HousePlacement (returns BadRegionTemp)
────────────────────────────────────────
Hook: Boat placement
Location: BaseBoatDeed.OnDoubleClick/OnPlacement
Mechanism: ContentFeatureFlags.BoatPlacement
────────────────────────────────────────
Hook: Bulk orders
Location: SmallBOD/LargeBOD
Mechanism: ContentFeatureFlags.BulkOrders
────────────────────────────────────────
Hook: Gump display
Location: GumpSystem.SendGump
Mechanism: FeatureFlagManager.IsGumpBlocked
────────────────────────────────────────
Hook: Item use
Location: PlayerMobile.AllowItemUse
Mechanism: FeatureFlagManager.IsItemUseBlocked
────────────────────────────────────────
Hook: Item equip
Location: PlayerMobile.CheckEquip
Mechanism: FeatureFlagManager.IsItemEquipBlocked
────────────────────────────────────────
Hook: Container access
Location: BaseContainer.DisplayTo
Mechanism: FeatureFlagManager.IsContainerAccessBlocked
────────────────────────────────────────
Hook: Skill use
Location: PlayerMobile.AllowSkillUse
Mechanism: FeatureFlagManager.IsSkillBlocked
────────────────────────────────────────
Hook: Spell casting
Location: Spell.Cast / Spellbook.CastSpellRequest
Mechanism: FeatureFlagManager.IsSpellBlocked
2026-02-07 12:02:57 -08:00
..
Advanced Search chore: Use var everywhere (#2294) 2025-12-27 16:47:28 -08:00
BuffIcons feat: Standardizes South/East selection gumps (#1839) 2025-02-14 00:15:14 -08:00
Bulk Orders feat: Adds Feature Flag System (#2328) 2026-02-07 12:02:57 -08:00
CannedEvil chore: Use var everywhere (#2294) 2025-12-27 16:47:28 -08:00
Character Creation chore: Use var everywhere (#2294) 2025-12-27 16:47:28 -08:00
Chat fix: Fixes thread guard and cleans up incoming packet reader (#1641) 2023-12-19 17:04:09 -08:00
ConPVP feat: Adds new decay system and SkipSerialization (#2311) 2026-01-08 11:43:51 -08:00
Craft chore: Use var everywhere (#2294) 2025-12-27 16:47:28 -08:00
Doom chore: Use var everywhere (#2294) 2025-12-27 16:47:28 -08:00
Ethics fix: Fixes ethics causing crashes when not used (#1972) 2024-10-15 17:02:11 -07:00
Events fix: Streamlines event scheduler API. Adds months to weekly recurrence (#2178) 2025-05-07 22:42:44 -07:00
Factions chore: Use var everywhere (#2294) 2025-12-27 16:47:28 -08:00
FeatureFlags feat: Adds Feature Flag System (#2328) 2026-02-07 12:02:57 -08:00
Harvest chore: Use var everywhere (#2294) 2025-12-27 16:47:28 -08:00
Help feat: Adds size/style support to gump builders, optimizes EscapeHtml (#2257) 2025-11-23 11:35:31 -08:00
Khaldun feat: Converts PuzzleChest to generator, optimizes (#2318) 2026-01-26 21:20:01 -06:00
ML Quests fix: Moves containers/bods/traps/etc to serialization generator (#2310) 2026-01-07 21:55:55 -08:00
Party chore: Use var everywhere (#2294) 2025-12-27 16:47:28 -08:00
Pathing feat: Refactors A* Movement to use PriorityQueue (#2244) 2025-07-26 15:53:06 -07:00
Plants feat: Adds new decay system and SkipSerialization (#2311) 2026-01-08 11:43:51 -08:00
Player Murder System chore: Use var everywhere (#2294) 2025-12-27 16:47:28 -08:00
Quests feat: Adds new decay system and SkipSerialization (#2311) 2026-01-08 11:43:51 -08:00
Spawners feat: Adds new decay system and SkipSerialization (#2311) 2026-01-08 11:43:51 -08:00
Stealables fix: Consolidates Color/Center html (#1762) 2024-05-07 23:56:32 -07:00
Treasures of Tokuno fix: Optimizes items to use default weights. (Part 1) (#2240) 2025-07-24 14:44:39 -07:00
UltimaStore fix: Fixes thread guard and cleans up incoming packet reader (#1641) 2023-12-19 17:04:09 -08:00
Veteran Rewards fix: Moves containers/bods/traps/etc to serialization generator (#2310) 2026-01-07 21:55:55 -08:00
Virtues feat: Add spawn position caching and spiral scan optimization (#2295) 2025-12-28 02:40:21 -08:00