minecraft-assets/data/minecraft/loot_tables/blocks/barrel.json

{
  "type": "minecraft:block",
  "pools": [
    {
      "bonus_rolls": 0.0,
      "conditions": [
        {
          "condition": "minecraft:survives_explosion"
        }
      ],
      "entries": [
        {
          "type": "minecraft:item",
          "functions": [
            {
              "components": [
                "minecraft:custom_name"
              ],
              "function": "minecraft:copy_components",
              "source": "block_entity"
            }
          ],
          "name": "minecraft:barrel"
        }
      ],
      "rolls": 1.0
    }
  ],
  "random_sequence": "minecraft:blocks/barrel"
}