Sending components of an item in HoverEvent is not possible

[Brokkonaut]

Bungeecord version

BungeeCord-Bootstrap:1.20-R0.3-SNAPSHOT:52ab21b:1844

Server version

No response

Client version

1.20.6

Bungeecord plugins

n/a

The bug

When creating a HoverEvent with a Item content the components of that item are not shown on the client (this also applies to spigot) I tried this on spigot with

            String itemTag = stack.getItemMeta().getAsString();
            msg.setHoverEvent(new HoverEvent(Action.SHOW_ITEM, new Item(stack.getType().getKey().toString(), 1, itemTag != null ? ItemTag.ofNbt(itemTag) : null)));

(i also tried stack.getItemMeta().getAsComponentString()) - both don't work, only the item type is shown but no enchantments, custom name or whatever. It was working in 1.20.4.

Log output (links)

No response

Checking

• I am using BungeeCord and not a fork. Issues with forks should not be reported here.
• I think this is not an issue with a bungeecord plugin.
• I have not read these checkboxes and therefore I just ticked them all.
• This is not a question or plugin creation help request.

[md-5]

cc/ @2008Choco

[2008Choco]

I'm unsure how you want to approach this now, but ItemSerializer tries to serialize it as id and tag, which doesn't exist anymore in vanilla. Id is now id (though I think we already serialize this), Count is now count, and tag is now components and is a Map of all the serialized components. So getAsComponentString() is correct, we're just not serializing it correctly in BungeeChat anymore. Do we want to have backwards compatibility for this?

An easily reproducible command is the followng:

/tellraw @p {"text":"[Hover me!]","hoverEvent":{"action":"show_item","contents":{"id": "minecraft:diamond_sword","count":1,"components":{"minecraft:enchantments":{"minecraft:sharpness":1}}}}}

EDIT:
Because Mojang isn't consistent for whatever reason, getComponentsAsString() returns the components surrounded in [] brackets as that's the format that's expected by /give. But that of course isn't valid when you're passing it to components in a hover event because it needs to be an actual map object, not a string. This suddenly got way more annoying to support because ItemTag now can't be represented as a string, but has to be represented as an object capable of being serialized identically to how components are serialized. We would need a BungeeCord equivalent of ItemMeta...

We could probably solve this in a really ugly way for Bukkit's own personal use by introducing a HoverEventProvider interface and having ItemStack implement it, but that doesn't solve the issue of supporting that in BungeeCord. It's also probably still annoying to implement in Bukkit. CraftBukkit would be fine, Bukkit, not so much. Immediate hacky solution I can think of at least is to serialize everything down and then manually concatenate the serialized string into the serialized JSON where "components" should be...

[Janmm14]

As it is a problem in (de-)serialization i have these suggestions:

• for improved drop-in compatibility we could assume incoming version = outgoing version and save a boolean/version integer in the Item / ItemTag. Bukkit can maybe set the default version to use
• we need to introduce a second gson instance in ComponentSerializer and add a target minecraft version parameter

[md-5]

We could probably solve this in a really ugly way for Bukkit's own personal use by introducing a HoverEventProvider interface and having ItemStack implement it, but that doesn't solve the issue of supporting that in BungeeCord. It's also probably still annoying to implement in Bukkit. CraftBukkit would be fine, Bukkit, not so much. Immediate hacky solution I can think of at least is to serialize everything down and then manually concatenate the serialized string into the serialized JSON where "components" should be...

I think this is fine, you put the interface in BungeeCord and have it return Map<String, Object> getAsComponent() or something to that effect (maybe even JsonElement since it can be specific to BungeeCord). If a Bungee plugin wants to display an Item of its own volition, then it can just parse that item from JSON (like it already would need to do for ItemTag/NBT)).

[2008Choco]

and have it return Map<String, Object> getAsComponent() or something to that effect (maybe even JsonElement since it can be specific to BungeeCord)

I think maybe instead we have it return a HoverEvent, no? Something like this:

public interface HoverEventProvider {

    public HoverEvent getAsHoverEvent(); // or just asHoverEvent()

}

[md-5]

Sorry yeah that probably makes more sense

[Remigio07]

Any updates on this?

[OstlerDev]

I was at least able to get this working by using the unsafe serializeItemAsJson function which does seem to be correctly serializing the components and when passed through to the hover event

private static final class HoverItem extends Content {
    private final String id;
    private final int count;
    private final JsonElement components;

    public HoverItem (JsonObject itemJson) 
    {
        JsonElement itemId = itemJson.get("id");
        JsonElement itemCount = itemJson.get("count");

        this.id = itemId != null ? itemId.getAsString() : null;
        this.count = itemCount != null ? itemCount.getAsInt() : -1;
        this.components = itemJson.get("components");
    }

    @Override
    public HoverEvent.Action requiredAction() {
        return HoverEvent.Action.SHOW_ITEM;
    }
}
// then when you want to use it
HoverEvent event = new HoverEvent(HoverEvent.Action.SHOW_ITEM, new HoverItem(Bukkit.getUnsafe().serializeItemAsJson(item)));

I also created a helper class that you can pass a Bukkit ItemStack to and get back a proper HoverEvent, it supports both the old nbt system and the new 1.20.5+ Item component system. This will likely be VERY helpful if you are still battling this issue and are okay with a solution that at least serves Paper based servers for now. ( @Remigio07 )

Example Usage:

HoverEvent hover = ItemHoverEventHelper.createFrom(ItemStack item)

ItemHoverEventHelper.java

package com.your.package.util;

import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import net.md_5.bungee.api.chat.HoverEvent;
import net.md_5.bungee.api.chat.hover.content.Content;
import org.bukkit.Bukkit;
import org.bukkit.inventory.ItemStack;
import java.util.Objects;

/**
 * Creates Bungee SHOW_ITEM hover events from a Bukkit ItemStack.
 *
 * Behavior:
 * - Paper 1.20.5+: Uses Paper’s serializeItemAsJson(..) which emits {id,count,components} on modern clients.
 * - Older/Non-Paper: Falls back to legacy NBT using ItemMeta#getAsString() → ItemTag (may miss components).
 *
 * Requirements:
 * - Paper API providing Bukkit.getUnsafe().serializeItemAsJson(ItemStack)
 * - Bungee chat serializer 1.21.5+ will inline show_item payloads automatically.
 *
 * Notes:
 * - This helper avoids NMS/CraftBukkit compile deps; relies only on Paper/Bukkit API.
 * - Components path preserves enchantments, names, lore, custom_data in hover.
 * - Fallback is best-effort for pre-1.20.5 servers or when components are unavailable.
 *
 * Example:
 *   HoverEvent hover = ItemHoverEventHelper.createFrom(itemStack);
 *   component.setHoverEvent(hover);
 */
public final class ItemHoverEventHelper {

    private ItemHoverEventHelper() {}

    /**
     * Build a SHOW_ITEM hover event for the provided Bukkit ItemStack.
     * Prefers modern components; falls back to legacy NBT tag if unavailable.
     *
     * @param bukkitItem Bukkit ItemStack
     * @return HoverEvent with SHOW_ITEM action suitable for modern clients
     */
    public static HoverEvent createFrom(final ItemStack bukkitItem) {
        try {
            // Note: `serializeItemAsJson` is a Paper API method
            JsonObject obj = Bukkit.getUnsafe().serializeItemAsJson(bukkitItem);
            if (obj != null) {
                final String id = obj.get("id").getAsString();
                final int count = bukkitItem.getAmount();
                // Get the new Item components field
                final JsonElement components = obj.get("components");
                if (components != null) {
                    return new HoverEvent(HoverEvent.Action.SHOW_ITEM, new ComponentsShowItem(id, count, components));
                }
            }
        } catch (Exception ignored) {
            // Paper-specific API not available, or old version; fall back to legacy tag path below
        }
        // There was either no components field (<1.20.5) or there was an error, regardless attempt the legacy method
        return createFromLegacy(bukkitItem);
    }

    // Old `nbt` Tag system if we are below 1.20.5
    private static HoverEvent createFromLegacy(final ItemStack bukkitItem) {
        final String id = bukkitItem.getType().getKey().toString();
        final int count = bukkitItem.getAmount();
        String nbt = null;
        try {
            nbt = bukkitItem.getItemMeta().getAsString();
            final net.md_5.bungee.api.chat.ItemTag tag = (nbt != null && !nbt.isEmpty()) ? net.md_5.bungee.api.chat.ItemTag.ofNbt(nbt) : null;
            return new HoverEvent(HoverEvent.Action.SHOW_ITEM, new net.md_5.bungee.api.chat.hover.content.Item(id, count, tag));
        } catch (Exception ignored) {
            // Some servers may not expose ItemMeta#getAsString; continue with null nbt
            // If this is an issue for you, take a look at using Item NBT API to get the nbt string
        }
        return new HoverEvent(HoverEvent.Action.SHOW_ITEM, new net.md_5.bungee.api.chat.hover.content.Item(id, count, null));
    }

    /** Minimal show_item content carrying components for modern clients. */
    private static final class ComponentsShowItem extends Content {
        private final String id;
        private final int count;
        private final JsonElement components;

        private ComponentsShowItem(final String id, final int count, final JsonElement components) {
            this.id = id;
            this.count = count;
            this.components = components;
        }

        @Override
        public HoverEvent.Action requiredAction() {
            return HoverEvent.Action.SHOW_ITEM;
        }

        @Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (o == null || getClass() != o.getClass()) return false;
            ComponentsShowItem that = (ComponentsShowItem) o;
            return count == that.count && Objects.equals(id, that.id) && Objects.equals(components, that.components);
        }

        @Override
        public int hashCode() {
            return Objects.hash(id, count, components);
        }
    }
}

Alternatively, if you are curious what the "Spigot" native way to do it is (since Spigot doesn't have serializeItemAsJson) here is a class that uses the Mojang serialization for the item stacks. It was hard to find this, but initial credit for turning me on to how I found this direction goes to Saukiya on the SpigotMC Forum. It gave me a kicking off point to dig deep and find this.

NMS Based Approach that calls the internal serialization codec

package com.your.package.util;

/**
 * This class is used to create hover events for items.
 * It uses direct NMS calls to serialize the item to a JSON object,
 * and then creates a hover event from that JSON object.
 * 
 * This is a workaround to the fact that the ItemStack class in Bukkit
 * does give easy access to the new Item Components Data system.
 */
public class ItemHoverUtil {

    private static Class<?> craftItemStackClass;
    private static java.lang.reflect.Method asNMSCopyMethod;
    private static net.minecraft.core.RegistryAccess.Frozen registryAccess;
    private static net.minecraft.resources.RegistryOps<com.google.gson.JsonElement> itemSerializationCodec;

    public static net.md_5.bungee.api.chat.HoverEvent getHoverEvent(org.bukkit.inventory.ItemStack bukkitItem) {
        return getHoverEventNMS(bukkitItem);
    }

    private static net.minecraft.world.item.ItemStack getMCItemStack(org.bukkit.inventory.ItemStack bukkitItem) {
        try {
            if (craftItemStackClass == null) {
                craftItemStackClass = Class.forName("org.bukkit.craftbukkit.inventory.CraftItemStack");
            }
            if (asNMSCopyMethod == null) {
                asNMSCopyMethod = craftItemStackClass.getMethod("asNMSCopy", org.bukkit.inventory.ItemStack.class);
            }
            return (net.minecraft.world.item.ItemStack) asNMSCopyMethod.invoke(null, bukkitItem);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    // 1.20.5+ create a hover event using the new Item Components Data system 
    // (which replaces NBT tags, which replaces... which replaces......... comeon mojang :c )
    public static net.md_5.bungee.api.chat.HoverEvent getHoverEventNMS(org.bukkit.inventory.ItemStack bukkitItem) {
        String id = null;
        int count = -1;
        com.google.gson.JsonElement components = null;

        if (registryAccess == null) {
            registryAccess = net.minecraft.server.MinecraftServer.getServer().registryAccess();
        }
        if (itemSerializationCodec == null) {
            itemSerializationCodec = registryAccess.createSerializationContext(com.mojang.serialization.JsonOps.INSTANCE);
        }
        final java.util.Optional<com.google.gson.JsonElement> encoded = net.minecraft.world.item.ItemStack.CODEC.encodeStart(itemSerializationCodec, getMCItemStack(bukkitItem)).result();
        if (encoded.isPresent()) {
            final com.google.gson.JsonObject itemJson = encoded.get().getAsJsonObject();
            id = itemJson.get("id").getAsString();
            count = itemJson.get("count").getAsInt();
            components = itemJson.get("components");
        }

        return new net.md_5.bungee.api.chat.HoverEvent(net.md_5.bungee.api.chat.HoverEvent.Action.SHOW_ITEM, new HoverItem(id, count, components));
    }

    /** Minimal show_item content carrying components for modern clients. */
    private static final class HoverItem extends net.md_5.bungee.api.chat.hover.content.Content {
        private final String id;
        private final int count;
        private final com.google.gson.JsonElement components;

        private HoverItem(final String id, final int count, final com.google.gson.JsonElement components) {
            this.id = id;
            this.count = count;
            this.components = components;
        }

        @Override
        public net.md_5.bungee.api.chat.HoverEvent.Action requiredAction() {
            return net.md_5.bungee.api.chat.HoverEvent.Action.SHOW_ITEM;
        }
    }
}

[OstlerDev]

I created a Merge Request with a simple change that adds the ability to create Item HoverEvent Content's using either JsonObject (item parent) or JsonElement (components only): #3873

This would make creating a HoverEvent for items as simple as this:

new HoverEvent(HoverEvent.Action.SHOW_ITEM, new Item(Bukkit.getUnsafe().serializeItemAsJson(item)))

[Remigio07]

Thank you for your time, I really appreciate your help!
Since the plugin I have been working on targets Spigot servers, I cannot really use the Paper API method, but I will definitely look into your reflection-based solution for a future rewrite, possibly before release. 🙂
I have been using a meticulously escaped /tellraw command for 1.20.5+ and BungeeCord Chat API components for older versions, but this was just a workaround.

[OstlerDev]

@Remigio07 happy to help :D I was struggling against this issue since 1.20.5 came out and have had so many server owners complain about having to use item-nbt-api and it not being instantly updated... Finally this should offer a native solution!