Blueprints did not load on startup resulting in number of errors

[wellnesscookie]

Description

Describe the bug

We did not update our bbox or addons for more than a week, but this morning blueprints did not load. Our blueprints folder: http://prntscr.com/ol36xn
/bsb bp list - lists all blueprints fine, but bsb bp GUI will show none bundles.

Steps to reproduce the behavior

As we did nothing, I do now know what had happened in order to reproduce.
Error on startup:
https://gist.github.com/wellnesscookie/54fd655f5d81dfe0064a0b41502f6f33
Errors on /is or /is create or /is restart:
https://pastebin.com/V0Uh5ncU

Expected behavior

Load blueprints as any day it did before this

Environment

Server

• OS: Linux Debian/ GNU 9
• Java version: Java 10

Plugins

Plugins (50): AnimatedNames*, AreaShop, ArmorStandTools, BentoBox, BungeeTabListPlus*, ChatControl, ChestCommands, ChestShop*, ClearLag*, CrateReloaded, EditableSign, Essentials, EssentialsChat*, EssentialsSpawn*, ExecuteEverywhere*, FastAsyncWorldEdit*, FeatherBoard*, HeadDatabase*, HolographicDisplays, HungerKeeperPlus*, IPWhitelist*, IslandBorder, LeaderHeads*, LibsDisguises, LuckPerms, MobManager*, Multiverse-Core*, MVdWPlaceholderAPI*, NickRemover*, NoSleepCMDs*, OpenInv*, PlayerHeads, PlayerPoints*, ProtocolLib*, PvPManager*, PvPManagerBossBar*, RedstoneClockDetector*, RPGHealthIndicator*, SilkSpawners, SkinsRestorer, Spartan, TradeMe, TrophyHeads*, UnbreakingAnvils*, Vault*, VoidGenerator, WorldEdit, WorldGuard, WorldGuardPistonFix*, Yamler*

BentoBox setup

BentoBox and Addons

[16:06:34] [main/INFO]: [CHAT] Running PAPER 1.13.2.
[16:06:34] [main/INFO]: [CHAT] BentoBox version: 1.6.0-SNAPSHOT-b1241
[16:06:34] [main/INFO]: [CHAT] Loaded Game Worlds:
[16:06:34] [main/INFO]: [CHAT] acidisland (acidisland): Overworld, Nether, End
[16:06:34] [main/INFO]: [CHAT] skyblock (skyblock): Overworld, Nether, End
[16:06:34] [main/INFO]: [CHAT] Loaded Addons:
[16:06:34] [main/INFO]: [CHAT] AcidIsland 1.5.0 (ENABLED)
[16:06:34] [main/INFO]: [CHAT] BentoBox-InvSwitcher 0.0.4 (ENABLED)
[16:06:34] [main/INFO]: [CHAT] Biomes 1.5.0.0 (ENABLED)
[16:06:34] [main/INFO]: [CHAT] BSkyBlock 1.5.0 (ENABLED)
[16:06:34] [main/INFO]: [CHAT] Challenges 0.7.5 (ENABLED)
[16:06:34] [main/INFO]: [CHAT] DimensionalTrees 1.1 - SerbCraft (ENABLED)
[16:06:34] [main/INFO]: [CHAT] Level 1.5.0 (ENABLED)
[16:06:34] [main/INFO]: [CHAT] Limits 0.2.3-SNAPSHOT (ENABLED)
[16:06:34] [main/INFO]: [CHAT] SerbCraftAddon 2.4 (ENABLED)
[16:06:34] [main/INFO]: [CHAT] WelcomeWarps 1.5.0 (ENABLED)

Configuration

• Database: mySQL

Additional context

[wellnesscookie]

They loaded fine after restart, but this was very odd and I'd like to keep the issue open until some1 can say what had happened and will it again.

Islands that failed to be pasted now have to be manually deleted with /bsb delete in order to fix it, otherwise unsafe teleportation message will be sent to all players that had their island created without the island self being pasted.

[tastybento]

Yes, Blueprints manager was performing badly in that build. I fixed the issue yesterday in e009cf5.

The error you are seeing is caused by line 193 here. The blueprintBundles get results in a null and errors out. However, in line 164, blueprintBundles should have been initialized with the addon and so should not be null. I cannot see a logical reason why that variable would become null, however, I do know that I was seeing the loadBundles method being called multiple times async before I fixed it yesterday so there could have been some kind of race condition going on. Just in case, I've added some defensive code to make sure a null cannot happen in the commits referenced in this ticket. I recommend you use the latest build.

Apart from that, I see that in the very first line of the console log it looks like there is still a schems folder in your addon folder. That should have been removed or renamed a long time ago, so I'm not sure why it's still there. The error is that the plugin is unable to move it to the schems-converted folder - maybe that folder already exists. So, I recommend you remove the old schems folder now.

[wellnesscookie]

Okay. The schems folder error is there for quite a time, but it copied them the first time blueprints build was used. Don't know why it didn't delete itself afterwards or whatever.

Anyway, thanks for this, we'll make sure we use the newest build, though this was very odd to happen since everyday before it worked perfectly.

[tastybento]

I found a way to replicate this and fix it. By repeatedly reloading the plugin I was able to trigger a situation like this. I don't know why doing that causes it, but I suspect that as the blueprint loading is async, it may be running multi-threaded at that point and a race condition will occur. So, anyway, I wrote the code in a way that it will not bomb out.

[tastybento]

Okay, I found the root cause - the HashMaps need to be ConcurrentHashMaps so that they can be loaded in a thread safe manner. When the blueprint bundles are loaded from multiple addons it's possible for their to be a clash, e.g., AcidIsland and BSkyBlock are both loading at the same time and the write of one of them is lost because of this clash.