Validate Transacton from_address_hash as required

It was marked null: false, but an optional parameter in
Transaction.changeset, so could trigger a database not-null constraint
violation.

apps/explorer/lib/explorer/chain/transaction.ex

@@ -7,9 +7,9 @@ defmodule Explorer.Chain.Transaction do
   alias Explorer.Chain.{Address, Block, Data, Gas, Hash, InternalTransaction, Log, Wei}
   alias Explorer.Chain.Transaction.Status
 
-  @optional_attrs ~w(block_hash block_number cumulative_gas_used from_address_hash gas_used index
-                     internal_transactions_indexed_at status to_address_hash)a
-  @required_attrs ~w(gas gas_price hash input nonce r s v value)a
+  @optional_attrs ~w(block_hash block_number cumulative_gas_used gas_used index internal_transactions_indexed_at status
+                     to_address_hash)a
+  @required_attrs ~w(from_address_hash gas gas_price hash input nonce r s v value)a
 
   @typedoc """
   X coordinate module n in
@@ -153,6 +153,7 @@ defmodule Explorer.Chain.Transaction do
       iex> changeset = Explorer.Chain.Transaction.changeset(
       ...>   %Transaction{},
       ...>   %{
+      ...>     from_address_hash: "0xe8ddc5c7a2d2f0d7a9798459c0104fdf5e987aca",
       ...>     gas: 4700000,
       ...>     gas_price: 100000000000,
       ...>     hash: "0x3a3eb134e6792ce9403ea4188e5e79693de9e4c94e499db132be086400da79e6",
@@ -173,6 +174,7 @@ defmodule Explorer.Chain.Transaction do
       iex> changeset = Explorer.Chain.Transaction.changeset(
       ...>   %Transaction{},
       ...>   %{
+      ...>     from_address_hash: "0xe8ddc5c7a2d2f0d7a9798459c0104fdf5e987aca",
       ...>     block_number: 34,
       ...>     cumulative_gas_used: 0,
       ...>     gas: 4700000,
@@ -210,6 +212,7 @@ defmodule Explorer.Chain.Transaction do
       ...>     block_hash: "0xe52d77084cab13a4e724162bcd8c6028e5ecfaa04d091ee476e96b9958ed6b47",
       ...>     block_number: 34,
       ...>     cumulative_gas_used: 0,
+      ...>     from_address_hash: "0xe8ddc5c7a2d2f0d7a9798459c0104fdf5e987aca",
       ...>     gas: 4700000,
       ...>     gas_price: 100000000000,
       ...>     gas_used: 4600000,

apps/explorer/test/explorer/chain/transaction_test.exs

@@ -10,6 +10,7 @@ defmodule Explorer.Chain.TransactionTest do
     test "with valid attributes" do
       assert %Changeset{valid?: true} =
                Transaction.changeset(%Transaction{}, %{
+                 from_address_hash: "0xe8ddc5c7a2d2f0d7a9798459c0104fdf5e987aca",
                  hash: "0x9fc76417374aa880d4449a1f7f31ec597f00b1f6f3dd2d66f4c9c6c445836d8b",
                  value: 1,
                  gas: 21000,
@@ -29,7 +30,7 @@ defmodule Explorer.Chain.TransactionTest do
     end
 
     test "it creates a new to address" do
-      params = params_for(:transaction)
+      params = params_for(:transaction, from_address_hash: "0xe8ddc5c7a2d2f0d7a9798459c0104fdf5e987aca")
       to_address_params = %{hash: "sk8orDi3"}
       changeset_params = Map.merge(params, %{to_address: to_address_params})