Don't replace_all fields of internal_transactions on_conflict

Fixes #978

Replace all field except the primary key and timestamps.  For the
primary key fields (transaction_hash, index), leave them as is as they
are the conflict target and have no changed by definition.  For the
timestamps that the least inserted_at and the greatest updated_at to
preserve the bounds of the timeline.

apps/explorer/lib/explorer/chain/import/internal_transactions.ex

@@ -58,7 +58,7 @@ defmodule Explorer.Chain.Import.InternalTransactions do
           | {:error, [Changeset.t()]}
   defp insert(changes_list, %{timeout: timeout, timestamps: timestamps} = options)
        when is_list(changes_list) do
-    on_conflict = Map.get(options, :on_conflict, :replace_all)
+    on_conflict = Map.get_lazy(options, :on_conflict, &default_on_conflict/0)
 
     # order so that row ShareLocks are grabbed in a consistent order
     ordered_changes_list = Enum.sort_by(changes_list, &{&1.transaction_hash, &1.index})
@@ -81,6 +81,36 @@ defmodule Explorer.Chain.Import.InternalTransactions do
      )}
   end
 
+  defp default_on_conflict do
+    from(
+      internal_transaction in InternalTransaction,
+      update: [
+        set: [
+          block_number: fragment("EXCLUDED.block_number"),
+          call_type: fragment("EXCLUDED.call_type"),
+          created_contract_address_hash: fragment("EXCLUDED.created_contract_address_hash"),
+          created_contract_code: fragment("EXCLUDED.created_contract_code"),
+          error: fragment("EXCLUDED.error"),
+          from_address_hash: fragment("EXCLUDED.from_address_hash"),
+          gas: fragment("EXCLUDED.gas"),
+          gas_used: fragment("EXCLUDED.gas_used"),
+          # Don't update `index` as it is part of the composite primary key and used for the conflict target
+          init: fragment("EXCLUDED.init"),
+          input: fragment("EXCLUDED.input"),
+          output: fragment("EXCLUDED.output"),
+          to_address_hash: fragment("EXCLUDED.to_address_hash"),
+          trace_address: fragment("EXCLUDED.trace_address"),
+          # Don't update `transaction_hash` as it is part of the composite primary key and used for the conflict target
+          transaction_index: fragment("EXCLUDED.transaction_index"),
+          type: fragment("EXCLUDED.type"),
+          value: fragment("EXCLUDED.value"),
+          inserted_at: fragment("LEAST(?, EXCLUDED.inserted_at)", internal_transaction.inserted_at),
+          updated_at: fragment("GREATEST(?, EXCLUDED.updated_at)", internal_transaction.updated_at)
+        ]
+      ]
+    )
+  end
+
   defp update_transactions(internal_transactions, %{
          timeout: timeout,
          timestamps: timestamps

apps/explorer/lib/explorer/chain/internal_transaction.ex

@@ -7,6 +7,7 @@ defmodule Explorer.Chain.InternalTransaction do
   alias Explorer.Chain.InternalTransaction.{CallType, Type}
 
   @typedoc """
+   * `block_number` - the `t:Explorer.Chain.Block.t/0` `number` that the `transaction` is collated into.
    * `call_type` - the type of call.  `nil` when `type` is not `:call`.
    * `created_contract_code` - the code of the contract that was created when `type` is `:create`.
    * `error` - error message when `:call` or `:create` `type` errors
@@ -23,13 +24,15 @@ defmodule Explorer.Chain.InternalTransaction do
    * `trace_address` - list of traces
    * `transaction` - transaction in which this transaction occurred
    * `transaction_hash` - foreign key for `transaction`
+   * `transaction_index` - the `t:Explorer.Chain.Transaction.t/0` `index` of `transaction` in `block_number`.
    * `type` - type of internal transaction
    * `value` - value of transferred from `from_address` to `to_address`
   """
   @type t :: %__MODULE__{
+          block_number: Explorer.Chain.Block.block_number() | nil,
           call_type: CallType.t() | nil,
           created_contract_address: %Ecto.Association.NotLoaded{} | Address.t() | nil,
-          created_contract_address_hash: Explorer.Chain.Hash.t() | nil,
+          created_contract_address_hash: Hash.t() | nil,
           created_contract_code: Data.t() | nil,
           error: String.t(),
           from_address: %Ecto.Association.NotLoaded{} | Address.t(),
@@ -44,7 +47,8 @@ defmodule Explorer.Chain.InternalTransaction do
           to_address_hash: Hash.Address.t() | nil,
           trace_address: [non_neg_integer()],
           transaction: %Ecto.Association.NotLoaded{} | Transaction.t(),
-          transaction_hash: Explorer.Chain.Hash.t(),
+          transaction_hash: Hash.t(),
+          transaction_index: Transaction.transaction_index() | nil,
           type: Type.t(),
           value: Wei.t()
         }