fix: Don't put error to NFT metadata (#9940)

* fix: Don't put error to NFT metadata

* Remove unused Explorer.Helper.maybe_decode/1

apps/explorer/lib/explorer/helper.ex

@@ -90,33 +90,24 @@ defmodule Explorer.Helper do
   Decode json
   """
   @spec decode_json(any()) :: map() | list() | nil
-  def decode_json(nil), do: nil
+  def decode_json(data, nft? \\ false)
 
-  def decode_json(data) do
+  def decode_json(nil, _), do: nil
+
+  def decode_json(data, nft?) do
     if String.valid?(data) do
-      safe_decode_json(data)
+      safe_decode_json(data, nft?)
     else
       data
       |> :unicode.characters_to_binary(:latin1)
-      |> safe_decode_json()
+      |> safe_decode_json(nft?)
     end
   end
 
-  defp safe_decode_json(data) do
+  defp safe_decode_json(data, nft?) do
     case Jason.decode(data) do
       {:ok, decoded} -> decoded
-      _ -> %{error: data}
-    end
-  end
-
-  @doc """
-    Tries to decode binary to json, return either decoded object, or initial binary
-  """
-  @spec maybe_decode(binary) :: any
-  def maybe_decode(data) do
-    case safe_decode_json(data) do
-      %{error: _} -> data
-      decoded -> decoded
+      _ -> if nft?, do: {:error, data}, else: %{error: data}
     end
   end
 

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

@@ -179,7 +179,7 @@ defmodule Indexer.Fetcher.TokenInstance.MetadataRetriever do
   end
 
   defp fetch_json_from_uri({:ok, [json]}, _ipfs?, _token_id, hex_token_id, _from_base_uri?) do
-    json = ExplorerHelper.decode_json(json)
+    json = ExplorerHelper.decode_json(json, true)
 
     check_type(json, hex_token_id)
   rescue
@@ -289,7 +289,7 @@ defmodule Indexer.Fetcher.TokenInstance.MetadataRetriever do
 
       check_type(json, nil)
     else
-      json = ExplorerHelper.decode_json(body)
+      json = ExplorerHelper.decode_json(body, true)
 
       check_type(json, hex_token_id)
     end

apps/indexer/test/indexer/fetcher/token_instance/helper_test.exs

@@ -3,6 +3,7 @@ defmodule Indexer.Fetcher.TokenInstance.HelperTest do
   use Explorer.DataCase
 
   alias Explorer.Chain.Token.Instance
+  alias Explorer.Repo
   alias EthereumJSONRPC.Encoder
   alias Indexer.Fetcher.TokenInstance.Helper
   alias Plug.Conn
@@ -15,6 +16,7 @@ defmodule Indexer.Fetcher.TokenInstance.HelperTest do
   setup do
     bypass = Bypass.open()
 
+    on_exit(fn -> Bypass.down(bypass) end)
     {:ok, bypass: bypass}
   end
 
@@ -311,5 +313,72 @@ defmodule Indexer.Fetcher.TokenInstance.HelperTest do
                 }}
              ] = Helper.batch_fetch_instances([{"0x5caebd3b32e210e85ce3e9d51638b9c445481567", 300_067_000_000_000_000}])
     end
+
+    test "check that decoding error is stored in error, not in metadata", %{bypass: bypass} do
+      json = """
+      invalid json
+      {
+        "name": "Sérgio Mendonça {id}"
+      }
+      """
+
+      encoded_url =
+        "0x" <>
+          (ABI.TypeEncoder.encode(["http://localhost:#{bypass.port}/api/card/{id}"], %ABI.FunctionSelector{
+             function: nil,
+             types: [
+               :string
+             ]
+           })
+           |> Base.encode16(case: :lower))
+
+      EthereumJSONRPC.Mox
+      |> expect(:json_rpc, fn [
+                                %{
+                                  id: 0,
+                                  jsonrpc: "2.0",
+                                  method: "eth_call",
+                                  params: [
+                                    %{
+                                      data:
+                                        "0x0e89341c0000000000000000000000000000000000000000000000000000000000000309",
+                                      to: "0x5caebd3b32e210e85ce3e9d51638b9c445481567"
+                                    },
+                                    "latest"
+                                  ]
+                                }
+                              ],
+                              _options ->
+        {:ok,
+         [
+           %{
+             id: 0,
+             jsonrpc: "2.0",
+             result: encoded_url
+           }
+         ]}
+      end)
+
+      Bypass.expect(
+        bypass,
+        "GET",
+        "/api/card/0000000000000000000000000000000000000000000000000000000000000309",
+        fn conn ->
+          Conn.resp(conn, 200, json)
+        end
+      )
+
+      insert(:token,
+        contract_address: build(:address, hash: "0x5caebd3b32e210e85ce3e9d51638b9c445481567"),
+        type: "ERC-1155"
+      )
+
+      Helper.batch_fetch_instances([{"0x5caebd3b32e210e85ce3e9d51638b9c445481567", 777}])
+
+      %Instance{
+        metadata: nil,
+        error: "wrong metadata type"
+      } = 777 |> Instance.token_instance_query("0x5caebd3b32e210e85ce3e9d51638b9c445481567") |> Repo.one()
+    end
   end
 end