fetch contract creation input data from transaction/internal transaction

apps/explorer/lib/explorer/chain.ex

@@ -1868,6 +1868,32 @@ defmodule Explorer.Chain do
     |> Data.to_string()
   end
 
+  @doc """
+  Fetches contract creation input data.
+  """
+  @spec contract_creation_input_data(String.t()) :: nil | String.t()
+  def contract_creation_input_data(address_hash) do
+    query =
+      from(
+        address in Address,
+        where: address.hash == ^address_hash,
+        preload: [:contracts_creation_internal_transaction, :contracts_creation_transaction]
+      )
+
+    transaction = Repo.one(query)
+
+    cond do
+      is_nil(transaction) ->
+        nil
+
+      !is_nil(transaction.contracts_creation_internal_transaction) ->
+        Data.to_string(transaction.contracts_creation_internal_transaction.input)
+
+      !is_nil(transaction.contracts_creation_transaction) ->
+        Data.to_string(transaction.contracts_creation_transaction.input)
+    end
+  end
+
   @doc """
   Inserts a `t:SmartContract.t/0`.
 

apps/explorer/test/explorer/chain_test.exs

@@ -3557,4 +3557,58 @@ defmodule Explorer.ChainTest do
       assert Chain.block_combined_rewards(block) == expected_value
     end
   end
+
+  describe "contract_creation_input_data/1" do
+    test "fetches contract creation input data from contract creation transaction" do
+      address = insert(:address)
+
+      input = %Data{
+        bytes: <<1, 2, 3, 4, 5>>
+      }
+
+      :transaction
+      |> insert(created_contract_address_hash: address.hash, input: input)
+      |> with_block()
+
+      found_creation_data = Chain.contract_creation_input_data(address.hash)
+
+      assert found_creation_data == Data.to_string(input)
+    end
+
+    test "fetches contract creation input data from internal transaction" do
+      created_contract_address = insert(:address)
+
+      transaction =
+        :transaction
+        |> insert()
+        |> with_block()
+
+      input = %Data{
+        bytes: <<1, 2, 3, 4, 5>>
+      }
+
+      insert(
+        :internal_transaction_create,
+        transaction: transaction,
+        index: 0,
+        created_contract_address: created_contract_address,
+        block_number: transaction.block_number,
+        transaction_index: transaction.index,
+        input: input
+      )
+
+      assert Chain.contract_creation_input_data(created_contract_address.hash) == Data.to_string(input)
+    end
+
+    test "can't find address" do
+      hash = %Hash{
+        byte_count: 20,
+        bytes: <<0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0>>
+      }
+
+      found_creation_data = Chain.contract_creation_input_data(hash)
+
+      assert is_nil(found_creation_data)
+    end
+  end
 end