Merge pull request #2770 from poanetwork/ab-do-not-refetch-token-instances-without-uris

do not re-fetch token instances without uris

CHANGELOG.md

@@ -16,6 +16,7 @@
 - [#2762](https://github.com/poanetwork/blockscout/pull/2762) - on-fly fetching of token instances
 
 ### Fixes
+- [#2770](https://github.com/poanetwork/blockscout/pull/2770) - do not re-fetch token instances without uris
 - [#2767](https://github.com/poanetwork/blockscout/pull/2767) - fix websocket subscriptions with token instances
 - [#2765](https://github.com/poanetwork/blockscout/pull/2765) - fixed width issue for cards in mobile view for Transaction Details page
 - [#2753](https://github.com/poanetwork/blockscout/pull/2753) - fix nft token instance images

apps/explorer/lib/explorer/chain/token/instance.ex

@@ -12,18 +12,21 @@ defmodule Explorer.Chain.Token.Instance do
   * `token_id` - ID of the token
   * `token_contract_address_hash` - Address hash foreign key
   * `metadata` - Token instance metadata
+  * `error` - error fetching token instance
   """
 
   @type t :: %Instance{
           token_id: non_neg_integer(),
           token_contract_address_hash: Hash.Address.t(),
-          metadata: Map.t()
+          metadata: Map.t(),
+          error: String.t()
         }
 
   @primary_key false
   schema "token_instances" do
     field(:token_id, :decimal, primary_key: true)
     field(:metadata, :map)
+    field(:error, :string)
 
     belongs_to(
       :token,
@@ -39,7 +42,7 @@ defmodule Explorer.Chain.Token.Instance do
 
   def changeset(%Instance{} = instance, params \\ %{}) do
     instance
-    |> cast(params, [:token_id, :metadata, :token_contract_address_hash])
+    |> cast(params, [:token_id, :metadata, :token_contract_address_hash, :error])
     |> validate_required([:token_id, :token_contract_address_hash])
     |> foreign_key_constraint(:token_contract_address_hash)
   end

apps/explorer/lib/explorer/token/instance_metadata_retriever.ex

@@ -29,6 +29,8 @@ defmodule Explorer.Token.InstanceMetadataRetriever do
 
   @cryptokitties_address_hash "0x06012c8cf97bead5deae237070f9587f8e7a266d"
 
+  @no_uri_error "no uri"
+
   def fetch_metadata(unquote(@cryptokitties_address_hash), token_id) do
     %{"tokenURI" => {:ok, ["https://api.cryptokitties.co/kitties/#{token_id}"]}}
     |> fetch_json()
@@ -47,13 +49,19 @@ defmodule Explorer.Token.InstanceMetadataRetriever do
   end
 
   defp fetch_json(%{"tokenURI" => {:ok, [""]}}) do
-    {:error, :no_uri}
+    {:ok, %{error: @no_uri_error}}
+  end
+
+  defp fetch_json(%{"tokenURI" => {:error, "(-32015) VM execution error."}}) do
+    {:ok, %{error: @no_uri_error}}
   end
 
   defp fetch_json(%{"tokenURI" => {:ok, [token_uri]}}) do
     case HTTPoison.get(token_uri) do
       {:ok, %Response{body: body, status_code: 200}} ->
-        Jason.decode(body)
+        {:ok, json} = Jason.decode(body)
+
+        {:ok, %{metadata: json}}
 
       {:ok, %Response{body: body}} ->
         {:error, body}

apps/explorer/priv/repo/migrations/20191010075740_add_error_to_token_instances.exs

@@ -0,0 +1,11 @@
+defmodule Explorer.Repo.Migrations.AddErrorToTokenInstances do
+  use Ecto.Migration
+
+  def change do
+    alter table(:token_instances) do
+      add(:error, :string)
+    end
+
+    create(index(:token_instances, [:error]))
+  end
+end

apps/explorer/test/explorer/chain_test.exs

@@ -173,6 +173,42 @@ defmodule Explorer.ChainTest do
          valid?: false
        }} = Chain.upsert_token_instance(params)
     end
+
+    test "inserts just an error without metadata" do
+      token = insert(:token)
+      error = "no uri"
+
+      params = %{
+        token_id: 1,
+        token_contract_address_hash: token.contract_address_hash,
+        error: error
+      }
+
+      {:ok, result} = Chain.upsert_token_instance(params)
+
+      assert result.error == error
+    end
+
+    test "nillifies error" do
+      token = insert(:token)
+
+      insert(:token_instance,
+        token_id: 1,
+        token_contract_address_hash: token.contract_address_hash,
+        error: "no uri"
+      )
+
+      params = %{
+        token_id: 1,
+        token_contract_address_hash: token.contract_address_hash,
+        metadata: %{uri: "http://example1.com"}
+      }
+
+      {:ok, result} = Chain.upsert_token_instance(params)
+
+      assert is_nil(result.error)
+      assert result.metadata == params.metadata
+    end
   end
 
   describe "address_to_logs/2" do

apps/explorer/test/support/factory.ex

@@ -547,7 +547,8 @@ defmodule Explorer.Factory do
     %Instance{
       token_contract_address_hash: build(:address),
       token_id: 5,
-      metadata: %{key: "value"}
+      metadata: %{key: "value"},
+      error: nil
     }
   end
 

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

@@ -50,11 +50,21 @@ defmodule Indexer.Fetcher.TokenInstance do
   @impl BufferedTask
   def run([%{contract_address_hash: token_contract_address_hash, token_id: token_id}], _json_rpc_named_arguments) do
     case InstanceMetadataRetriever.fetch_metadata(to_string(token_contract_address_hash), Decimal.to_integer(token_id)) do
-      {:ok, metadata} ->
+      {:ok, %{metadata: metadata}} ->
         params = %{
           token_id: token_id,
           token_contract_address_hash: token_contract_address_hash,
-          metadata: metadata
+          metadata: metadata,
+          error: nil
+        }
+
+        {:ok, _result} = Chain.upsert_token_instance(params)
+
+      {:ok, %{error: error}} ->
+        params = %{
+          token_id: token_id,
+          token_contract_address_hash: token_contract_address_hash,
+          error: error
         }
 
         {:ok, _result} = Chain.upsert_token_instance(params)