on-fly fetching of token instances

CHANGELOG.md

@@ -13,6 +13,7 @@
 - [#2665](https://github.com/poanetwork/blockscout/pull/2665) - new menu layout for mobile devices
 - [#2663](https://github.com/poanetwork/blockscout/pull/2663) - Fetch address counters in parallel
 - [#2642](https://github.com/poanetwork/blockscout/pull/2642) - add ERC721 coin instance page
+- [#2762](https://github.com/poanetwork/blockscout/pull/2762) - on-fly fetching of token instances
 
 ### Fixes
 - [#2767](https://github.com/poanetwork/blockscout/pull/2767) - fix websocket subscriptions with token instances

apps/indexer/lib/indexer/block/catchup/fetcher.ex

@@ -16,6 +16,7 @@ defmodule Indexer.Block.Catchup.Fetcher do
       async_import_replaced_transactions: 1,
       async_import_tokens: 1,
       async_import_token_balances: 1,
+      async_import_token_instances: 1,
       async_import_uncles: 1,
       fetch_and_import_range: 2
     ]
@@ -164,6 +165,7 @@ defmodule Indexer.Block.Catchup.Fetcher do
     async_import_token_balances(imported)
     async_import_uncles(imported)
     async_import_replaced_transactions(imported)
+    async_import_token_instances(imported)
   end
 
   defp stream_fetch_and_import(%__MODULE__{blocks_concurrency: blocks_concurrency} = state, sequence)

apps/indexer/lib/indexer/block/fetcher.ex

@@ -25,6 +25,7 @@ defmodule Indexer.Block.Fetcher do
     StakingPools,
     Token,
     TokenBalance,
+    TokenInstance,
     UncleBlock
   }
 
@@ -229,6 +230,12 @@ defmodule Indexer.Block.Fetcher do
     callback_module.import(state, options_with_broadcast)
   end
 
+  def async_import_token_instances(%{token_transfers: token_transfers}) do
+    TokenInstance.async_fetch(token_transfers)
+  end
+
+  def async_import_token_instances(_), do: :ok
+
   def async_import_block_rewards([]), do: :ok
 
   def async_import_block_rewards(errors) when is_list(errors) do

apps/indexer/lib/indexer/block/realtime/fetcher.ex

@@ -19,6 +19,7 @@ defmodule Indexer.Block.Realtime.Fetcher do
       async_import_replaced_transactions: 1,
       async_import_tokens: 1,
       async_import_token_balances: 1,
+      async_import_token_instances: 1,
       async_import_uncles: 1,
       fetch_and_import_range: 2,
       async_import_staking_pools: 0
@@ -358,6 +359,7 @@ defmodule Indexer.Block.Realtime.Fetcher do
     async_import_internal_transactions(imported, Keyword.get(json_rpc_named_arguments, :variant))
     async_import_tokens(imported)
     async_import_token_balances(imported)
+    async_import_token_instances(imported)
     async_import_uncles(imported)
     async_import_replaced_transactions(imported)
     async_import_staking_pools()

apps/indexer/lib/indexer/fetcher/token_instance.ex

@@ -69,6 +69,18 @@ defmodule Indexer.Fetcher.TokenInstance do
   @doc """
   Fetches token instance data asynchronously.
   """
+  def async_fetch(token_transfers) when is_list(token_transfers) do
+    data =
+      token_transfers
+      |> Enum.reject(fn token_transfer -> is_nil(token_transfer.token_id) end)
+      |> Enum.map(fn token_transfer ->
+        %{contract_address_hash: token_transfer.token_contract_address_hash, token_id: token_transfer.token_id}
+      end)
+      |> Enum.uniq()
+
+    BufferedTask.buffer(__MODULE__, data)
+  end
+
   def async_fetch(data) do
     BufferedTask.buffer(__MODULE__, data)
   end