From 8a1d20b1c86883a5d21dee0a1c2ed0a606d55c24 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Tue, 6 Aug 2019 13:20:05 +0300
Subject: [PATCH 01/20] add POA emission rewards importer

---
 .../lib/explorer/chain_spec/poa/importer.ex   | 79 +++++++++++++++++++
 1 file changed, 79 insertions(+)
 create mode 100644 apps/explorer/lib/explorer/chain_spec/poa/importer.ex

diff --git a/apps/explorer/lib/explorer/chain_spec/poa/importer.ex b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
new file mode 100644
index 0000000000..45e18e6d1c
--- /dev/null
+++ b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
@@ -0,0 +1,79 @@
+defmodule Explorer.ChainSpec.POA.Importer do
+  @moduledoc """
+  Imports emission reward range for POA chain.
+  """
+
+  alias Explorer.Chain.Wei
+  alias Explorer.Repo
+  alias Explorer.SmartContract.Reader
+  alias Explorer.Chain.Block.{EmissionReward, Range}
+
+  @reward_by_block_contract_address "0xeca443e8e1ab29971a45a9c57a6a9875701698a5"
+  @block_reward_amount_abi %{
+    "type" => "function",
+    "stateMutability" => "view",
+    "payable" => false,
+    "outputs" => [%{"type" => "uint256", "name" => ""}],
+    "name" => "blockRewardAmount",
+    "inputs" => [],
+    "constant" => true
+  }
+  @block_reward_amount_params %{"blockRewardAmount" => []}
+  @emission_funds_amount_abi %{
+    "type" => "function",
+    "stateMutability" => "view",
+    "payable" => false,
+    "outputs" => [%{"type" => "uint256", "name" => ""}],
+    "name" => "emissionFundsAmount",
+    "inputs" => [],
+    "constant" => true
+  }
+  @emission_funds_amount_params %{"emissionFundsAmount" => []}
+  @emission_funds_block_start 5_098_087
+
+  def import_emission_rewards do
+    block_reward = block_reward_amount()
+    emission_funds = emission_funds_amount()
+
+    rewards = [
+      %{
+        block_range: %Range{from: 0, to: @emission_funds_block_start},
+        reward: %Wei{value: block_reward}
+      },
+      %{
+        block_range: %Range{from: @emission_funds_block_start + 1, to: :infinity},
+        reward: %Wei{value: Decimal.add(block_reward, emission_funds)}
+      }
+    ]
+
+    {_, nil} = Repo.delete_all(EmissionReward)
+    {_, nil} = Repo.insert_all(EmissionReward, rewards)
+  end
+
+  def block_reward_amount do
+    call_contract(@reward_by_block_contract_address, @block_reward_amount_abi, @block_reward_amount_params)
+  end
+
+  def emission_funds_amount do
+    call_contract(@reward_by_block_contract_address, @emission_funds_amount_abi, @emission_funds_amount_params)
+  end
+
+  defp call_contract(address, abi, params) do
+    abi = [abi]
+
+    method_name =
+      params
+      |> Enum.map(fn {key, _value} -> key end)
+      |> List.first()
+
+    Reader.query_contract(address, abi, params)
+
+    value =
+      case Reader.query_contract(address, abi, params) do
+        %{^method_name => {:ok, [result]}} -> result
+        _ -> 0
+      end
+
+    Decimal.new(value)
+  end
+end

From dd2a8116452d14e862b6d55d7c13fdcb4ee042a2 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Fri, 16 Aug 2019 16:17:07 +0300
Subject: [PATCH 02/20] add verification submission comment

---
 .../templates/address_contract/index.html.eex |  2 +-
 .../views/address_contract_view.ex            |  9 +++++---
 apps/explorer/lib/explorer/chain.ex           | 22 +++++++++++++++++--
 .../lib/explorer/chain/smart_contract.ex      | 22 +++++++++++++++++++
 4 files changed, 49 insertions(+), 6 deletions(-)

diff --git a/apps/block_scout_web/lib/block_scout_web/templates/address_contract/index.html.eex b/apps/block_scout_web/lib/block_scout_web/templates/address_contract/index.html.eex
index e8d6501e02..0b2f4f7574 100644
--- a/apps/block_scout_web/lib/block_scout_web/templates/address_contract/index.html.eex
+++ b/apps/block_scout_web/lib/block_scout_web/templates/address_contract/index.html.eex
@@ -66,7 +66,7 @@
             </button>
           </div>
           <div class="tile tile-muted mb-4">
-            <pre class="pre-scrollable line-numbers" data-activate-highlight><code class="solidity"><%= for {line, number} <- contract_lines_with_index(@address.smart_contract.contract_source_code) do %><div data-line-number="<%= number %>"><%= line %></div><% end %></code></pre>
+            <pre class="pre-scrollable line-numbers" data-activate-highlight><code class="solidity"><%= for {line, number} <- contract_lines_with_index(@address.smart_contract) do %><div data-line-number="<%= number %>"><%= line %></div><% end %></code></pre>
           </div>
         </section>
 
diff --git a/apps/block_scout_web/lib/block_scout_web/views/address_contract_view.ex b/apps/block_scout_web/lib/block_scout_web/views/address_contract_view.ex
index 57c6e11da7..0ad32985c4 100644
--- a/apps/block_scout_web/lib/block_scout_web/views/address_contract_view.ex
+++ b/apps/block_scout_web/lib/block_scout_web/views/address_contract_view.ex
@@ -2,7 +2,7 @@ defmodule BlockScoutWeb.AddressContractView do
   use BlockScoutWeb, :view
 
   alias ABI.{FunctionSelector, TypeDecoder}
-  alias Explorer.Chain.{Address, Data, InternalTransaction}
+  alias Explorer.Chain.{Address, Data, InternalTransaction, SmartContract}
 
   def render("scripts.html", %{conn: conn}) do
     render_scripts(conn, "address_contract/code_highlighting.js")
@@ -63,8 +63,11 @@ defmodule BlockScoutWeb.AddressContractView do
     end)
   end
 
-  def contract_lines_with_index(contract_source_code) do
-    contract_lines = String.split(contract_source_code, "\n")
+  def contract_lines_with_index(contract_contract) do
+    contract_lines =
+      contract_contract.contract_source_code
+      |> String.split("\n")
+      |> SmartContract.add_submitted_comment(contract_contract.inserted_at)
 
     max_digits =
       contract_lines
diff --git a/apps/explorer/lib/explorer/chain.ex b/apps/explorer/lib/explorer/chain.ex
index 58253c0f27..979e5975a8 100644
--- a/apps/explorer/lib/explorer/chain.ex
+++ b/apps/explorer/lib/explorer/chain.ex
@@ -2532,8 +2532,26 @@ defmodule Explorer.Chain do
   @spec address_hash_to_address_with_source_code(Hash.Address.t()) :: Address.t() | nil
   def address_hash_to_address_with_source_code(address_hash) do
     case Repo.get(Address, address_hash) do
-      nil -> nil
-      address -> Repo.preload(address, [:smart_contract, :decompiled_smart_contracts])
+      nil ->
+        nil
+
+      address ->
+        address_with_smart_contract = Repo.preload(address, [:smart_contract, :decompiled_smart_contracts])
+
+        if address_with_smart_contract.smart_contract do
+          formatted_code =
+            SmartContract.add_submitted_comment(
+              address_with_smart_contract.smart_contract.contract_source_code,
+              address_with_smart_contract.smart_contract.inserted_at
+            )
+
+          %{
+            address_with_smart_contract
+            | smart_contract: %{address_with_smart_contract.smart_contract | contract_source_code: formatted_code}
+          }
+        else
+          address_with_smart_contract
+        end
     end
   end
 
diff --git a/apps/explorer/lib/explorer/chain/smart_contract.ex b/apps/explorer/lib/explorer/chain/smart_contract.ex
index ed579e8e00..e11e8a6d78 100644
--- a/apps/explorer/lib/explorer/chain/smart_contract.ex
+++ b/apps/explorer/lib/explorer/chain/smart_contract.ex
@@ -271,6 +271,28 @@ defmodule Explorer.Chain.SmartContract do
     |> add_error(:contract_source_code, error_message(error))
   end
 
+  def add_submitted_comment(code, inserted_at) when is_binary(code) do
+    code
+    |> String.split("\n")
+    |> add_submitted_commet(inserted_at)
+    |> Enum.join("\n")
+  end
+
+  def add_submitted_comment(contract_lines, inserted_at) when is_list(contract_lines) do
+    index =
+      Enum.find(contract_lines, fn line ->
+        String.contains?(line, "Submitted for verification at Etherscan.io")
+      end)
+
+    if index do
+      List.replace_at(contract_lines, index, "* Submitted for verification at blockscout.com")
+    else
+      header = ["/**", "* Submitted for verification at blockscout.com on #{inserted_at}", "*/"]
+
+      header ++ contract_lines
+    end
+  end
+
   defp upsert_contract_methods(%Ecto.Changeset{changes: %{abi: abi}} = changeset) do
     ContractMethod.upsert_from_abi(abi, get_field(changeset, :address_hash))
 

From 5d035b9a0256efdc41ea4f949c62eeb9dfc2094a Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Fri, 16 Aug 2019 16:21:33 +0300
Subject: [PATCH 03/20] fix typo

---
 apps/explorer/lib/explorer/chain/smart_contract.ex | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/apps/explorer/lib/explorer/chain/smart_contract.ex b/apps/explorer/lib/explorer/chain/smart_contract.ex
index e11e8a6d78..7a88110f71 100644
--- a/apps/explorer/lib/explorer/chain/smart_contract.ex
+++ b/apps/explorer/lib/explorer/chain/smart_contract.ex
@@ -274,7 +274,7 @@ defmodule Explorer.Chain.SmartContract do
   def add_submitted_comment(code, inserted_at) when is_binary(code) do
     code
     |> String.split("\n")
-    |> add_submitted_commet(inserted_at)
+    |> add_submitted_comment(inserted_at)
     |> Enum.join("\n")
   end
 

From 01ab9a5a317efb6d3bc96c68c0cba4506a35406f Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Fri, 16 Aug 2019 16:22:53 +0300
Subject: [PATCH 04/20] add CHANGELOG entry

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f006769dbf..a58616d9bb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,7 @@
 ## Current
 
 ### Features
+- [#1588](https://github.com/poanetwork/blockscout/pull/2588) - add verification submission comment
 - [#2561](https://github.com/poanetwork/blockscout/pull/2561) - Add token's type to the response of tokenlist method
 - [#2499](https://github.com/poanetwork/blockscout/pull/2499) - import emission reward ranges
 - [#2497](https://github.com/poanetwork/blockscout/pull/2497) - Add generic Ordered Cache behaviour and implementation

From c15c9bd70565c54f1502c514fd1cb3b7391f7a34 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Fri, 16 Aug 2019 16:40:55 +0300
Subject: [PATCH 05/20] fix tests

---
 .../templates/address_contract/index.html.eex |  2 +-
 .../views/address_contract_view.ex            |  6 +--
 .../views/address_contract_view_test.exs      | 47 ++++++++++++-------
 .../lib/explorer/chain/smart_contract.ex      |  2 +-
 4 files changed, 35 insertions(+), 22 deletions(-)

diff --git a/apps/block_scout_web/lib/block_scout_web/templates/address_contract/index.html.eex b/apps/block_scout_web/lib/block_scout_web/templates/address_contract/index.html.eex
index 0b2f4f7574..1e98048169 100644
--- a/apps/block_scout_web/lib/block_scout_web/templates/address_contract/index.html.eex
+++ b/apps/block_scout_web/lib/block_scout_web/templates/address_contract/index.html.eex
@@ -66,7 +66,7 @@
             </button>
           </div>
           <div class="tile tile-muted mb-4">
-            <pre class="pre-scrollable line-numbers" data-activate-highlight><code class="solidity"><%= for {line, number} <- contract_lines_with_index(@address.smart_contract) do %><div data-line-number="<%= number %>"><%= line %></div><% end %></code></pre>
+            <pre class="pre-scrollable line-numbers" data-activate-highlight><code class="solidity"><%= for {line, number} <- contract_lines_with_index(@address.smart_contract.contract_source_code, @address.smart_contract.inserted_at) do %><div data-line-number="<%= number %>"><%= line %></div><% end %></code></pre>
           </div>
         </section>
 
diff --git a/apps/block_scout_web/lib/block_scout_web/views/address_contract_view.ex b/apps/block_scout_web/lib/block_scout_web/views/address_contract_view.ex
index 0ad32985c4..f9128dfb11 100644
--- a/apps/block_scout_web/lib/block_scout_web/views/address_contract_view.ex
+++ b/apps/block_scout_web/lib/block_scout_web/views/address_contract_view.ex
@@ -63,11 +63,11 @@ defmodule BlockScoutWeb.AddressContractView do
     end)
   end
 
-  def contract_lines_with_index(contract_contract) do
+  def contract_lines_with_index(source_code, inserted_at \\ nil) do
     contract_lines =
-      contract_contract.contract_source_code
+      source_code
       |> String.split("\n")
-      |> SmartContract.add_submitted_comment(contract_contract.inserted_at)
+      |> SmartContract.add_submitted_comment(inserted_at)
 
     max_digits =
       contract_lines
diff --git a/apps/block_scout_web/test/block_scout_web/views/address_contract_view_test.exs b/apps/block_scout_web/test/block_scout_web/views/address_contract_view_test.exs
index 4bcb1eb2bf..9f0314fb88 100644
--- a/apps/block_scout_web/test/block_scout_web/views/address_contract_view_test.exs
+++ b/apps/block_scout_web/test/block_scout_web/views/address_contract_view_test.exs
@@ -38,22 +38,25 @@ defmodule BlockScoutWeb.AddressContractViewTest do
       result = AddressContractView.contract_lines_with_index(code)
 
       assert result == [
-               {"pragma solidity >=0.4.22 <0.6.0;", " 1"},
-               {"", " 2"},
-               {"struct Proposal {", " 3"},
-               {"  uint voteCount;", " 4"},
-               {"}", " 5"},
-               {"", " 6"},
-               {"address chairperson;", " 7"},
-               {"mapping(address => Voter) voters;", " 8"},
-               {"Proposal[] proposals;", " 9"},
-               {"", "10"},
-               {"constructor(uint8 _numProposals) public {", "11"},
-               {"  chairperson = msg.sender;", "12"},
-               {"  voters[chairperson].weight = 1;", "13"},
-               {"  proposals.length = _numProposals;", "14"},
-               {"}", "15"},
-               {"", "16"}
+               {"/**", " 1"},
+               {"* Submitted for verification at blockscout.com on ", " 2"},
+               {"*/", " 3"},
+               {"pragma solidity >=0.4.22 <0.6.0;", " 4"},
+               {"", " 5"},
+               {"struct Proposal {", " 6"},
+               {"  uint voteCount;", " 7"},
+               {"}", " 8"},
+               {"", " 9"},
+               {"address chairperson;", "10"},
+               {"mapping(address => Voter) voters;", "11"},
+               {"Proposal[] proposals;", "12"},
+               {"", "13"},
+               {"constructor(uint8 _numProposals) public {", "14"},
+               {"  chairperson = msg.sender;", "15"},
+               {"  voters[chairperson].weight = 1;", "16"},
+               {"  proposals.length = _numProposals;", "17"},
+               {"}", "18"},
+               {"", "19"}
              ]
     end
 
@@ -66,7 +69,17 @@ defmodule BlockScoutWeb.AddressContractViewTest do
 
     test "returns a list of tuples and the first element is just a line from the original string" do
       result = AddressContractView.contract_lines_with_index("a\nb\nc\nd\ne")
-      assert Enum.map(result, fn {line, _number} -> line end) == ["a", "b", "c", "d", "e"]
+
+      assert Enum.map(result, fn {line, _number} -> line end) == [
+               "/**",
+               "* Submitted for verification at blockscout.com on ",
+               "*/",
+               "a",
+               "b",
+               "c",
+               "d",
+               "e"
+             ]
     end
   end
 end
diff --git a/apps/explorer/lib/explorer/chain/smart_contract.ex b/apps/explorer/lib/explorer/chain/smart_contract.ex
index 7a88110f71..bbddd51100 100644
--- a/apps/explorer/lib/explorer/chain/smart_contract.ex
+++ b/apps/explorer/lib/explorer/chain/smart_contract.ex
@@ -285,7 +285,7 @@ defmodule Explorer.Chain.SmartContract do
       end)
 
     if index do
-      List.replace_at(contract_lines, index, "* Submitted for verification at blockscout.com")
+      List.replace_at(contract_lines, index, "* Submitted for verification at blockscout.com on #{inserted_at}")
     else
       header = ["/**", "* Submitted for verification at blockscout.com on #{inserted_at}", "*/"]
 

From cb3cc8eb65bcd942cc0a9deaa47248838e42d5c6 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Mon, 19 Aug 2019 10:54:01 +0300
Subject: [PATCH 06/20] fix api/rpc/contract_controller_test

---
 .../api/rpc/contract_controller_test.exs      | 20 +++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/apps/block_scout_web/test/block_scout_web/controllers/api/rpc/contract_controller_test.exs b/apps/block_scout_web/test/block_scout_web/controllers/api/rpc/contract_controller_test.exs
index e070cf8e57..af9daffed8 100644
--- a/apps/block_scout_web/test/block_scout_web/controllers/api/rpc/contract_controller_test.exs
+++ b/apps/block_scout_web/test/block_scout_web/controllers/api/rpc/contract_controller_test.exs
@@ -1,6 +1,6 @@
 defmodule BlockScoutWeb.API.RPC.ContractControllerTest do
   use BlockScoutWeb.ConnCase
-  alias Explorer.Factory
+  alias Explorer.{Chain, Factory}
 
   describe "listcontracts" do
     setup do
@@ -422,7 +422,9 @@ defmodule BlockScoutWeb.API.RPC.ContractControllerTest do
       expected_result = [
         %{
           "Address" => to_string(contract.address_hash),
-          "SourceCode" => contract.contract_source_code,
+          "SourceCode" =>
+            "/**\n* Submitted for verification at blockscout.com on #{contract.inserted_at}\n*/\n" <>
+              contract.contract_source_code,
           "ABI" => Jason.encode!(contract.abi),
           "ContractName" => contract.name,
           "CompilerVersion" => contract.compiler_version,
@@ -467,9 +469,13 @@ defmodule BlockScoutWeb.API.RPC.ContractControllerTest do
         |> get("/api", params)
         |> json_response(200)
 
+      verified_contract = Chain.address_hash_to_smart_contract(contract_address.hash)
+
       expected_result = %{
         "Address" => to_string(contract_address.hash),
-        "SourceCode" => contract_code_info.source_code,
+        "SourceCode" =>
+          "/**\n* Submitted for verification at blockscout.com on #{verified_contract.inserted_at}\n*/\n" <>
+            contract_code_info.source_code,
         "ABI" => Jason.encode!(contract_code_info.abi),
         "ContractName" => contract_code_info.name,
         "CompilerVersion" => contract_code_info.version,
@@ -533,8 +539,14 @@ defmodule BlockScoutWeb.API.RPC.ContractControllerTest do
 
       result = response["result"]
 
+      verified_contract = Chain.address_hash_to_smart_contract(contract_address.hash)
+
       assert result["Address"] == to_string(contract_address.hash)
-      assert result["SourceCode"] == contract_source_code
+
+      assert result["SourceCode"] ==
+               "/**\n* Submitted for verification at blockscout.com on #{verified_contract.inserted_at}\n*/\n" <>
+                 contract_source_code
+
       assert result["ContractName"] == name
       assert result["DecompiledSourceCode"] == "Contract source code not decompiled."
       assert result["DecompilerVersion"] == ""

From e73280aafcc5e561d03307f66ad2802e9c38086a Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Mon, 19 Aug 2019 14:48:36 +0300
Subject: [PATCH 07/20] Update CHANGELOG.md

---
 CHANGELOG.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a58616d9bb..203f2dcce1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,7 +1,7 @@
 ## Current
 
 ### Features
-- [#1588](https://github.com/poanetwork/blockscout/pull/2588) - add verification submission comment
+- [#2588](https://github.com/poanetwork/blockscout/pull/2588) - add verification submission comment
 - [#2561](https://github.com/poanetwork/blockscout/pull/2561) - Add token's type to the response of tokenlist method
 - [#2499](https://github.com/poanetwork/blockscout/pull/2499) - import emission reward ranges
 - [#2497](https://github.com/poanetwork/blockscout/pull/2497) - Add generic Ordered Cache behaviour and implementation

From f9676bc04833c735df3558b422a657fdf7821d23 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Mon, 19 Aug 2019 15:13:34 +0300
Subject: [PATCH 08/20] integrate poa emission rewards to supervision tree

---
 apps/explorer/config/config.exs                |  6 +++++-
 .../lib/explorer/chain_spec/parity/importer.ex | 18 ++++++++++++++----
 .../lib/explorer/chain_spec/poa/importer.ex    |  9 ++++++---
 3 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/apps/explorer/config/config.exs b/apps/explorer/config/config.exs
index 95c80ba445..e4ba8ef577 100644
--- a/apps/explorer/config/config.exs
+++ b/apps/explorer/config/config.exs
@@ -27,7 +27,11 @@ config :explorer, Explorer.Counters.AverageBlockTime,
   enabled: true,
   period: average_block_period
 
-config :explorer, Explorer.ChainSpec.GenesisData, enabled: true, chain_spec_path: System.get_env("CHAIN_SPEC_PATH")
+config :explorer, Explorer.ChainSpec.GenesisData,
+  enabled: true,
+  chain_spec_path: System.get_env("CHAIN_SPEC_PATH"),
+  emission_format: System.get_env("EMISSION_FORMAT", "DEFAULT"),
+  rewards_contract_address: System.get_env("REWARDS_CONTRACT_ADDRESS", "0xeca443e8e1ab29971a45a9c57a6a9875701698a5")
 
 config :explorer, Explorer.Chain.Cache.BlockNumber, enabled: true
 
diff --git a/apps/explorer/lib/explorer/chain_spec/parity/importer.ex b/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
index 6b560bf530..620acfb934 100644
--- a/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
+++ b/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
@@ -7,14 +7,17 @@ defmodule Explorer.ChainSpec.Parity.Importer do
   alias Explorer.Chain.Block.{EmissionReward, Range}
   alias Explorer.Chain.Hash.Address, as: AddressHash
   alias Explorer.Chain.Wei
+  alias Explorer.ChainSpec.GenesisData
+  alias Explorer.ChainSpec.POA.Importer, as: PoaEmissionImporter
 
   @max_block_number :infinity
 
   def import_emission_rewards(chain_spec) do
-    rewards = emission_rewards(chain_spec)
-
-    {_, nil} = Repo.delete_all(EmissionReward)
-    {_, nil} = Repo.insert_all(EmissionReward, rewards)
+    if Application.get_env(:explorer, GenesisData)[:emission_format] == "POA" do
+      PoaEmissionImporter.import_emission_rewards()
+    else
+      import_rewards_from_chain_spec(chain_spec)
+    end
   end
 
   def import_genesis_coin_balances(chain_spec) do
@@ -38,6 +41,13 @@ defmodule Explorer.ChainSpec.Parity.Importer do
     Chain.import(params)
   end
 
+  defp import_rewards_from_chain_spec(chain_spec) do
+    rewards = emission_rewards(chain_spec)
+
+    {_, nil} = Repo.delete_all(EmissionReward)
+    {_, nil} = Repo.insert_all(EmissionReward, rewards)
+  end
+
   def genesis_coin_balances(chain_spec) do
     accounts = chain_spec["accounts"]
 
diff --git a/apps/explorer/lib/explorer/chain_spec/poa/importer.ex b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
index 45e18e6d1c..80d2c23696 100644
--- a/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
+++ b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
@@ -8,7 +8,6 @@ defmodule Explorer.ChainSpec.POA.Importer do
   alias Explorer.SmartContract.Reader
   alias Explorer.Chain.Block.{EmissionReward, Range}
 
-  @reward_by_block_contract_address "0xeca443e8e1ab29971a45a9c57a6a9875701698a5"
   @block_reward_amount_abi %{
     "type" => "function",
     "stateMutability" => "view",
@@ -51,11 +50,15 @@ defmodule Explorer.ChainSpec.POA.Importer do
   end
 
   def block_reward_amount do
-    call_contract(@reward_by_block_contract_address, @block_reward_amount_abi, @block_reward_amount_params)
+    call_contract(rewards_contract_address(), @block_reward_amount_abi, @block_reward_amount_params)
   end
 
   def emission_funds_amount do
-    call_contract(@reward_by_block_contract_address, @emission_funds_amount_abi, @emission_funds_amount_params)
+    call_contract(rewards_contract_address(), @emission_funds_amount_abi, @emission_funds_amount_params)
+  end
+
+  defp rewards_contract_address do
+    Application.get_env(:explorer, GenesisData)[:rewards_contract_address]
   end
 
   defp call_contract(address, abi, params) do

From e76400aa5816b26a47b21ad92625d1b6d641e06a Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Mon, 19 Aug 2019 15:14:03 +0300
Subject: [PATCH 09/20] add env vars

---
 docs/env-variables.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/docs/env-variables.md b/docs/env-variables.md
index 60c9eee442..83d0de41ab 100644
--- a/docs/env-variables.md
+++ b/docs/env-variables.md
@@ -54,6 +54,8 @@ $ export NETWORK=POA
 | `LINK_TO_OTHER_EXPLORERS` | | true/false. If true, links to other explorers are added in the footer  | (empty)  |  v1.3.0+ |
 | `COINMARKETCAP_PAGES` | | the number of pages on coinmarketcap to list in order to find token's price  | 10 |  v1.3.10+ |
 | `CHAIN_SPEC_PATH` | | Chain specification path (absolute file system path or url) to import block emission reward ranges and genesis account balances from | (empty) | master |
+| `EMISSION_FORMAT` | | Should be set to `POA` if you have block emission indentical to POA Network. This env var is used only if `CHAIN_SPEC_PATH` is set | `STANDARD` | master
+| `REWARDS_CONTRACT_ADDRESS` | | Emission rewards contract address. This env var is used only if `EMISSION_FORMAT` is set to `POA` | `0xeca443e8e1ab29971a45a9c57a6a9875701698a5` | master
 | `SUPPORTED_CHAINS` | | Array of supported chains that displays in the footer and in the chains dropdown. This var was introduced in this PR [#1900](https://github.com/poanetwork/blockscout/pull/1900) and looks like an array of JSON objects.  | (empty) |  v2.0.0+ |
 | `BLOCK_COUNT_CACHE_PERIOD ` | | time to live of cache in seconds. This var was introduced in [#1876](https://github.com/poanetwork/blockscout/pull/1876)  | 600 |  v2.0.0+ |
 | `ALLOWED_EVM_VERSIONS ` | | the comma-separated list of allowed EVM versions for contracts verification. This var was introduced in [#1964](https://github.com/poanetwork/blockscout/pull/1964)  | "homestead, tangerineWhistle, spuriousDragon, byzantium, constantinople, petersburg" |  v2.0.0+ |

From f3f72fdf6c9c54cd360ca4d2c3089c9dd8782ae2 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Mon, 19 Aug 2019 15:24:20 +0300
Subject: [PATCH 10/20] fix POA Importer

---
 .../lib/explorer/chain_spec/poa/importer.ex   | 22 ++++++++++---------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/apps/explorer/lib/explorer/chain_spec/poa/importer.ex b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
index 80d2c23696..154d904703 100644
--- a/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
+++ b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
@@ -7,6 +7,7 @@ defmodule Explorer.ChainSpec.POA.Importer do
   alias Explorer.Repo
   alias Explorer.SmartContract.Reader
   alias Explorer.Chain.Block.{EmissionReward, Range}
+  alias Explorer.ChainSpec.GenesisData
 
   @block_reward_amount_abi %{
     "type" => "function",
@@ -34,16 +35,17 @@ defmodule Explorer.ChainSpec.POA.Importer do
     block_reward = block_reward_amount()
     emission_funds = emission_funds_amount()
 
-    rewards = [
-      %{
-        block_range: %Range{from: 0, to: @emission_funds_block_start},
-        reward: %Wei{value: block_reward}
-      },
-      %{
-        block_range: %Range{from: @emission_funds_block_start + 1, to: :infinity},
-        reward: %Wei{value: Decimal.add(block_reward, emission_funds)}
-      }
-    ]
+    rewards =
+      [
+        %{
+          block_range: %Range{from: 0, to: @emission_funds_block_start},
+          reward: %Wei{value: block_reward}
+        },
+        %{
+          block_range: %Range{from: @emission_funds_block_start + 1, to: :infinity},
+          reward: %Wei{value: Decimal.add(block_reward, emission_funds)}
+        }
+      ]
 
     {_, nil} = Repo.delete_all(EmissionReward)
     {_, nil} = Repo.insert_all(EmissionReward, rewards)

From 7b174fad2ea767e46c81a3ab5091bc8644d648e6 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Mon, 19 Aug 2019 15:25:56 +0300
Subject: [PATCH 11/20] add CHANGELOG entry

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f006769dbf..167578e6a7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,7 @@
 ## Current
 
 ### Features
+- [#2505](https://github.com/poanetwork/blockscout/pull/2505) - support POA Network emission rewards
 - [#2561](https://github.com/poanetwork/blockscout/pull/2561) - Add token's type to the response of tokenlist method
 - [#2499](https://github.com/poanetwork/blockscout/pull/2499) - import emission reward ranges
 - [#2497](https://github.com/poanetwork/blockscout/pull/2497) - Add generic Ordered Cache behaviour and implementation

From e51efc5e062c6c65b626718ea7943698fca4afca Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Mon, 19 Aug 2019 15:53:10 +0300
Subject: [PATCH 12/20] mix format

---
 .../lib/explorer/chain_spec/poa/importer.ex   | 21 +++++++++----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/apps/explorer/lib/explorer/chain_spec/poa/importer.ex b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
index 154d904703..d731f08aa6 100644
--- a/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
+++ b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
@@ -35,17 +35,16 @@ defmodule Explorer.ChainSpec.POA.Importer do
     block_reward = block_reward_amount()
     emission_funds = emission_funds_amount()
 
-    rewards =
-      [
-        %{
-          block_range: %Range{from: 0, to: @emission_funds_block_start},
-          reward: %Wei{value: block_reward}
-        },
-        %{
-          block_range: %Range{from: @emission_funds_block_start + 1, to: :infinity},
-          reward: %Wei{value: Decimal.add(block_reward, emission_funds)}
-        }
-      ]
+    rewards = [
+      %{
+        block_range: %Range{from: 0, to: @emission_funds_block_start},
+        reward: %Wei{value: block_reward}
+      },
+      %{
+        block_range: %Range{from: @emission_funds_block_start + 1, to: :infinity},
+        reward: %Wei{value: Decimal.add(block_reward, emission_funds)}
+      }
+    ]
 
     {_, nil} = Repo.delete_all(EmissionReward)
     {_, nil} = Repo.insert_all(EmissionReward, rewards)

From c58723f641a63ae1e7eb6200a9c50e2e251131c9 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Tue, 20 Aug 2019 15:27:56 +0300
Subject: [PATCH 13/20] do not try to parse data if there is none

---
 .../lib/explorer/chain_spec/parity/importer.ex   | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/apps/explorer/lib/explorer/chain_spec/parity/importer.ex b/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
index 620acfb934..8c3527d9e4 100644
--- a/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
+++ b/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
@@ -51,15 +51,23 @@ defmodule Explorer.ChainSpec.Parity.Importer do
   def genesis_coin_balances(chain_spec) do
     accounts = chain_spec["accounts"]
 
-    parse_accounts(accounts)
+    if accounts do
+      parse_accounts(accounts)
+    else
+      Logger.warn(fn -> "No accounts are defined in chain spec" end)
+    end
   end
 
   def emission_rewards(chain_spec) do
     rewards = chain_spec["engine"]["Ethash"]["params"]["blockReward"]
 
-    rewards
-    |> parse_hex_numbers()
-    |> format_ranges()
+    if rewards do
+      rewards
+      |> parse_hex_numbers()
+      |> format_ranges()
+    else
+      Logger.warn(fn -> "No rewards are defined in chain spec" end)
+    end
   end
 
   defp parse_accounts(accounts) do

From c6b0a86c0b836ea558b85857fa43475d5366e391 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Tue, 20 Aug 2019 15:31:06 +0300
Subject: [PATCH 14/20] require logger

---
 apps/explorer/lib/explorer/chain_spec/poa/importer.ex | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/apps/explorer/lib/explorer/chain_spec/poa/importer.ex b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
index d731f08aa6..00d54a3d74 100644
--- a/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
+++ b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
@@ -3,6 +3,8 @@ defmodule Explorer.ChainSpec.POA.Importer do
   Imports emission reward range for POA chain.
   """
 
+  require Logger
+
   alias Explorer.Chain.Wei
   alias Explorer.Repo
   alias Explorer.SmartContract.Reader

From 44ac58116ff458e2d431c9e308fd02aa68c48445 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Tue, 20 Aug 2019 15:36:25 +0300
Subject: [PATCH 15/20] add logger to poa rewards importer

---
 .../explorer/chain_spec/parity/importer.ex    |  2 ++
 .../lib/explorer/chain_spec/poa/importer.ex   | 32 +++++++++++--------
 2 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/apps/explorer/lib/explorer/chain_spec/parity/importer.ex b/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
index 8c3527d9e4..a1f620ec6c 100644
--- a/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
+++ b/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
@@ -3,6 +3,8 @@ defmodule Explorer.ChainSpec.Parity.Importer do
   Imports data from parity chain spec.
   """
 
+  require Logger
+
   alias Explorer.{Chain, Repo}
   alias Explorer.Chain.Block.{EmissionReward, Range}
   alias Explorer.Chain.Hash.Address, as: AddressHash
diff --git a/apps/explorer/lib/explorer/chain_spec/poa/importer.ex b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
index 00d54a3d74..03935d85b2 100644
--- a/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
+++ b/apps/explorer/lib/explorer/chain_spec/poa/importer.ex
@@ -34,22 +34,26 @@ defmodule Explorer.ChainSpec.POA.Importer do
   @emission_funds_block_start 5_098_087
 
   def import_emission_rewards do
-    block_reward = block_reward_amount()
-    emission_funds = emission_funds_amount()
+    if is_nil(rewards_contract_address()) do
+      Logger.warn(fn -> "No rewards contract address is defined" end)
+    else
+      block_reward = block_reward_amount()
+      emission_funds = emission_funds_amount()
 
-    rewards = [
-      %{
-        block_range: %Range{from: 0, to: @emission_funds_block_start},
-        reward: %Wei{value: block_reward}
-      },
-      %{
-        block_range: %Range{from: @emission_funds_block_start + 1, to: :infinity},
-        reward: %Wei{value: Decimal.add(block_reward, emission_funds)}
-      }
-    ]
+      rewards = [
+        %{
+          block_range: %Range{from: 0, to: @emission_funds_block_start},
+          reward: %Wei{value: block_reward}
+        },
+        %{
+          block_range: %Range{from: @emission_funds_block_start + 1, to: :infinity},
+          reward: %Wei{value: Decimal.add(block_reward, emission_funds)}
+        }
+      ]
 
-    {_, nil} = Repo.delete_all(EmissionReward)
-    {_, nil} = Repo.insert_all(EmissionReward, rewards)
+      {_, nil} = Repo.delete_all(EmissionReward)
+      {_, nil} = Repo.insert_all(EmissionReward, rewards)
+    end
   end
 
   def block_reward_amount do

From a89f96944eed7911406a7c39b0f8f80f605230df Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Wed, 28 Aug 2019 10:25:57 +0300
Subject: [PATCH 16/20] update env-vars doc file

---
 docs/env-variables.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/env-variables.md b/docs/env-variables.md
index e79dd4473f..8a1165839f 100644
--- a/docs/env-variables.md
+++ b/docs/env-variables.md
@@ -54,8 +54,8 @@ $ export NETWORK=POA
 | `LINK_TO_OTHER_EXPLORERS` | | true/false. If true, links to other explorers are added in the footer  | (empty)  |  v1.3.0+ |
 | `COINMARKETCAP_PAGES` | | the number of pages on coinmarketcap to list in order to find token's price  | 10 |  v1.3.10+ |
 | `CHAIN_SPEC_PATH` | | Chain specification path (absolute file system path or url) to import block emission reward ranges and genesis account balances from | (empty) | master |
-| `EMISSION_FORMAT` | | Should be set to `POA` if you have block emission indentical to POA Network. This env var is used only if `CHAIN_SPEC_PATH` is set | `STANDARD` | master
-| `REWARDS_CONTRACT_ADDRESS` | | Emission rewards contract address. This env var is used only if `EMISSION_FORMAT` is set to `POA` | `0xeca443e8e1ab29971a45a9c57a6a9875701698a5` | master
+| `EMISSION_FORMAT` | | Should be set to `POA` if you have block emission indentical to POA Network. This env var is used only if `CHAIN_SPEC_PATH` is set | `STANDARD` | master |
+| `REWARDS_CONTRACT_ADDRESS` | | Emission rewards contract address. This env var is used only if `EMISSION_FORMAT` is set to `POA` | `0xeca443e8e1ab29971a45a9c57a6a9875701698a5` | master |
 | `SUPPORTED_CHAINS` | | Array of supported chains that displays in the footer and in the chains dropdown. This var was introduced in this PR [#1900](https://github.com/poanetwork/blockscout/pull/1900) and looks like an array of JSON objects.  | (empty) |  v2.0.0+ |
 | `BLOCK_COUNT_CACHE_PERIOD ` | | time to live of cache in seconds. This var was introduced in [#1876](https://github.com/poanetwork/blockscout/pull/1876)  | 600 |  v2.0.0+ |
 | `ALLOWED_EVM_VERSIONS ` | | the comma-separated list of allowed EVM versions for contracts verification. This var was introduced in [#1964](https://github.com/poanetwork/blockscout/pull/1964)  | "homestead, tangerineWhistle, spuriousDragon, byzantium, constantinople, petersburg" |  v2.0.0+ |

From 4b9ef3dad3580fe529b60a01be716ab7a9d2476f Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Wed, 28 Aug 2019 11:18:19 +0300
Subject: [PATCH 17/20] parse decimal data from genesis chain spec

---
 .../lib/explorer/chain_spec/parity/importer.ex | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/apps/explorer/lib/explorer/chain_spec/parity/importer.ex b/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
index a1f620ec6c..fa16ee0739 100644
--- a/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
+++ b/apps/explorer/lib/explorer/chain_spec/parity/importer.ex
@@ -57,6 +57,8 @@ defmodule Explorer.ChainSpec.Parity.Importer do
       parse_accounts(accounts)
     else
       Logger.warn(fn -> "No accounts are defined in chain spec" end)
+
+      []
     end
   end
 
@@ -69,6 +71,8 @@ defmodule Explorer.ChainSpec.Parity.Importer do
       |> format_ranges()
     else
       Logger.warn(fn -> "No rewards are defined in chain spec" end)
+
+      []
     end
   end
 
@@ -79,7 +83,7 @@ defmodule Explorer.ChainSpec.Parity.Importer do
     end)
     |> Stream.map(fn {address, %{"balance" => value}} ->
       {:ok, address_hash} = AddressHash.cast(address)
-      balance = parse_hex_number(value)
+      balance = parse_number(value)
 
       %{address_hash: address_hash, value: balance}
     end)
@@ -112,16 +116,22 @@ defmodule Explorer.ChainSpec.Parity.Importer do
 
   defp parse_hex_numbers(rewards) do
     Enum.map(rewards, fn {hex_block_number, hex_reward} ->
-      block_number = parse_hex_number(hex_block_number)
-      {:ok, reward} = hex_reward |> parse_hex_number() |> Wei.cast()
+      block_number = parse_number(hex_block_number)
+      {:ok, reward} = hex_reward |> parse_number() |> Wei.cast()
 
       {block_number, reward}
     end)
   end
 
-  defp parse_hex_number("0x" <> hex_number) do
+  defp parse_number("0x" <> hex_number) do
     {number, ""} = Integer.parse(hex_number, 16)
 
     number
   end
+
+  defp parse_number(string_number) do
+    {number, ""} = Integer.parse(string_number, 10)
+
+    number
+  end
 end

From f28e866f8fd766d91bb8d6d63a8f42214d5c2e9d Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Mon, 2 Sep 2019 11:27:45 +0300
Subject: [PATCH 18/20] check if blockscout comment is already added

---
 .../lib/explorer/chain/smart_contract.ex      | 29 +++++++++++++++----
 1 file changed, 23 insertions(+), 6 deletions(-)

diff --git a/apps/explorer/lib/explorer/chain/smart_contract.ex b/apps/explorer/lib/explorer/chain/smart_contract.ex
index bbddd51100..a3c198c642 100644
--- a/apps/explorer/lib/explorer/chain/smart_contract.ex
+++ b/apps/explorer/lib/explorer/chain/smart_contract.ex
@@ -279,17 +279,34 @@ defmodule Explorer.Chain.SmartContract do
   end
 
   def add_submitted_comment(contract_lines, inserted_at) when is_list(contract_lines) do
-    index =
+    etherscan_index =
       Enum.find(contract_lines, fn line ->
         String.contains?(line, "Submitted for verification at Etherscan.io")
       end)
 
-    if index do
-      List.replace_at(contract_lines, index, "* Submitted for verification at blockscout.com on #{inserted_at}")
-    else
-      header = ["/**", "* Submitted for verification at blockscout.com on #{inserted_at}", "*/"]
+    blockscout_index =
+      Enum.find(contract_lines, fn line ->
+        String.contains?(line, "Submitted for verification at blockscout.com")
+      end)
+
+    cond do
+      etherscan_index && blockscout_index ->
+        List.replace_at(contract_lines, etherscan_index, "*")
+
+      etherscan_index && !blockscout_index ->
+        List.replace_at(
+          contract_lines,
+          etherscan_index,
+          "* Submitted for verification at blockscout.com on #{inserted_at}"
+        )
+
+      !etherscan_index && !blockscout_index ->
+        header = ["/**", "* Submitted for verification at blockscout.com on #{inserted_at}", "*/"]
+
+        header ++ contract_lines
 
-      header ++ contract_lines
+      true ->
+        contract_lines
     end
   end
 

From 327b762528f5fbffb478ee5aead16c276725eef4 Mon Sep 17 00:00:00 2001
From: Ayrat Badykov <ayratin555@gmail.com>
Date: Tue, 3 Sep 2019 12:56:38 +0300
Subject: [PATCH 19/20] find index of the comment instead of item

---
 apps/explorer/lib/explorer/chain/smart_contract.ex | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/apps/explorer/lib/explorer/chain/smart_contract.ex b/apps/explorer/lib/explorer/chain/smart_contract.ex
index a3c198c642..0db7d7e613 100644
--- a/apps/explorer/lib/explorer/chain/smart_contract.ex
+++ b/apps/explorer/lib/explorer/chain/smart_contract.ex
@@ -280,12 +280,12 @@ defmodule Explorer.Chain.SmartContract do
 
   def add_submitted_comment(contract_lines, inserted_at) when is_list(contract_lines) do
     etherscan_index =
-      Enum.find(contract_lines, fn line ->
+      Enum.find_index(contract_lines, fn line ->
         String.contains?(line, "Submitted for verification at Etherscan.io")
       end)
 
     blockscout_index =
-      Enum.find(contract_lines, fn line ->
+      Enum.find_index(contract_lines, fn line ->
         String.contains?(line, "Submitted for verification at blockscout.com")
       end)
 

From c856a5926096ee644d12ab5ade22eec339b0c217 Mon Sep 17 00:00:00 2001
From: saneery <anatolyniky@gmail.com>
Date: Wed, 21 Aug 2019 14:52:38 +0300
Subject: [PATCH 20/20] Add caches updating independently from Indexer

---
 CHANGELOG.md                                  |  1 +
 apps/explorer/config/config.exs               | 13 +++++-
 apps/explorer/lib/explorer/application.ex     |  4 +-
 .../lib/explorer/chain/cache/block_number.ex  |  4 +-
 .../lib/explorer/chain/cache/blocks.ex        |  4 +-
 .../lib/explorer/chain/cache/transactions.ex  |  4 +-
 .../lib/explorer/chain/ordered_cache.ex       | 42 +++++++++++++++----
 .../chain/cache/block_number_test.exs         |  6 +--
 8 files changed, 61 insertions(+), 17 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f347667b27..4d8ddf8ca0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@
 - [#2497](https://github.com/poanetwork/blockscout/pull/2497) - Add generic Ordered Cache behaviour and implementation
 
 ### Fixes
+- [#2612](https://github.com/poanetwork/blockscout/pull/2612) - Add cache updating independently from Indexer
 - [#2659](https://github.com/poanetwork/blockscout/pull/2659) - Multipurpose front-end part update
 - [#2468](https://github.com/poanetwork/blockscout/pull/2468) - fix confirmations for non consensus blocks
 - [#2610](https://github.com/poanetwork/blockscout/pull/2610) - use CoinGecko instead of CoinMarketcap for exchange rates
diff --git a/apps/explorer/config/config.exs b/apps/explorer/config/config.exs
index 10e8a66e82..e118362b40 100644
--- a/apps/explorer/config/config.exs
+++ b/apps/explorer/config/config.exs
@@ -29,7 +29,10 @@ config :explorer, Explorer.Counters.AverageBlockTime,
 
 config :explorer, Explorer.ChainSpec.GenesisData, enabled: false, chain_spec_path: System.get_env("CHAIN_SPEC_PATH")
 
-config :explorer, Explorer.Chain.Cache.BlockNumber, enabled: true
+config :explorer, Explorer.Chain.Cache.BlockNumber,
+  enabled: true,
+  ttl_check_interval: if(System.get_env("DISABLE_INDEXER") == "true", do: :timer.seconds(1), else: false),
+  global_ttl: if(System.get_env("DISABLE_INDEXER") == "true", do: :timer.seconds(5))
 
 config :explorer, Explorer.ExchangeRates.Source.CoinGecko, coin_id: System.get_env("COIN_GECKO_ID", "poa-network")
 
@@ -123,6 +126,14 @@ market_history_cache_period =
 
 config :explorer, Explorer.Market.MarketHistoryCache, period: market_history_cache_period
 
+config :explorer, Explorer.Chain.Cache.Blocks,
+  ttl_check_interval: if(System.get_env("DISABLE_INDEXER") == "true", do: :timer.seconds(1), else: false),
+  global_ttl: if(System.get_env("DISABLE_INDEXER") == "true", do: :timer.seconds(5))
+
+config :explorer, Explorer.Chain.Cache.Transactions,
+  ttl_check_interval: if(System.get_env("DISABLE_INDEXER") == "true", do: :timer.seconds(1), else: false),
+  global_ttl: if(System.get_env("DISABLE_INDEXER") == "true", do: :timer.seconds(5))
+
 # Import environment specific config. This must remain at the bottom
 # of this file so it overrides the configuration defined above.
 import_config "#{Mix.env()}.exs"
diff --git a/apps/explorer/lib/explorer/application.ex b/apps/explorer/lib/explorer/application.ex
index 1bd2778762..7c55d28f76 100644
--- a/apps/explorer/lib/explorer/application.ex
+++ b/apps/explorer/lib/explorer/application.ex
@@ -56,9 +56,7 @@ defmodule Explorer.Application do
 
     opts = [strategy: :one_for_one, name: Explorer.Supervisor]
 
-    res = Supervisor.start_link(children, opts)
-
-    res
+    Supervisor.start_link(children, opts)
   end
 
   defp configurable_children do
diff --git a/apps/explorer/lib/explorer/chain/cache/block_number.ex b/apps/explorer/lib/explorer/chain/cache/block_number.ex
index d19551fa59..fb5f1b515a 100644
--- a/apps/explorer/lib/explorer/chain/cache/block_number.ex
+++ b/apps/explorer/lib/explorer/chain/cache/block_number.ex
@@ -7,7 +7,9 @@ defmodule Explorer.Chain.Cache.BlockNumber do
 
   use Explorer.Chain.MapCache,
     name: :block_number,
-    keys: [:min, :max]
+    keys: [:min, :max],
+    ttl_check_interval: Application.get_env(:explorer, __MODULE__)[:ttl_check_interval],
+    global_ttl: Application.get_env(:explorer, __MODULE__)[:global_ttl]
 
   alias Explorer.Chain
 
diff --git a/apps/explorer/lib/explorer/chain/cache/blocks.ex b/apps/explorer/lib/explorer/chain/cache/blocks.ex
index 4a18646d37..d2a5b47061 100644
--- a/apps/explorer/lib/explorer/chain/cache/blocks.ex
+++ b/apps/explorer/lib/explorer/chain/cache/blocks.ex
@@ -11,7 +11,9 @@ defmodule Explorer.Chain.Cache.Blocks do
     ids_list_key: "block_numbers",
     preload: :transactions,
     preload: [miner: :names],
-    preload: :rewards
+    preload: :rewards,
+    ttl_check_interval: Application.get_env(:explorer, __MODULE__)[:ttl_check_interval],
+    global_ttl: Application.get_env(:explorer, __MODULE__)[:global_ttl]
 
   @type element :: Block.t()
 
diff --git a/apps/explorer/lib/explorer/chain/cache/transactions.ex b/apps/explorer/lib/explorer/chain/cache/transactions.ex
index 7dee7ec87d..e9b8a40a9e 100644
--- a/apps/explorer/lib/explorer/chain/cache/transactions.ex
+++ b/apps/explorer/lib/explorer/chain/cache/transactions.ex
@@ -16,7 +16,9 @@ defmodule Explorer.Chain.Cache.Transactions do
       token_transfers: :token,
       token_transfers: :from_address,
       token_transfers: :to_address
-    ]
+    ],
+    ttl_check_interval: Application.get_env(:explorer, __MODULE__)[:ttl_check_interval],
+    global_ttl: Application.get_env(:explorer, __MODULE__)[:global_ttl]
 
   @type element :: Transaction.t()
 
diff --git a/apps/explorer/lib/explorer/chain/ordered_cache.ex b/apps/explorer/lib/explorer/chain/ordered_cache.ex
index 2a1c0fc689..5365fe0f76 100644
--- a/apps/explorer/lib/explorer/chain/ordered_cache.ex
+++ b/apps/explorer/lib/explorer/chain/ordered_cache.ex
@@ -26,7 +26,10 @@ defmodule Explorer.Chain.OrderedCache do
       preload: [transaction: :hash]
   ```
   Additionally all of the options accepted by `ConCache.start_link/1` can be
-  provided as well. By default only `ttl_check_interval:` is set (to `false`).
+  provided as well. Unless specified, only these values have defaults:
+  - `:ttl_check_interval` is set (to `false`).
+  - `:callback` is only set if `:ttl_check_interval` is not `false` to call the
+    `remove_deleted_from_index` function, that removes expired values from the index.
 
   It's also possible, and advised, to override the implementation of the `c:prevails?/2`
   and `c:element_to_id/1` callbacks.
@@ -131,10 +134,7 @@ defmodule Explorer.Chain.OrderedCache do
     max_size = Keyword.get(opts, :max_size, 100)
     preloads = Keyword.get(opts, :preloads) || Keyword.get_values(opts, :preload)
 
-    concache_params =
-      opts
-      |> Keyword.drop([:ids_list_key, :max_size, :preloads, :preload])
-      |> Keyword.put_new(:ttl_check_interval, false)
+    concache_params = Keyword.drop(opts, [:ids_list_key, :max_size, :preloads, :preload])
 
     # credo:disable-for-next-line Credo.Check.Refactor.LongQuoteBlocks
     quote do
@@ -206,6 +206,19 @@ defmodule Explorer.Chain.OrderedCache do
 
       ### Updating function
 
+      def remove_deleted_from_index({:delete, _cache_pid, id}) do
+        # simply check with `ConCache.get` because it is faster
+        if Enum.member?(ids_list(), id) do
+          ConCache.update(cache_name(), ids_list_key(), fn ids ->
+            updated_list = List.delete(ids || [], id)
+            # ids_list is set to never expire
+            {:ok, %ConCache.Item{value: updated_list, ttl: :infinity}}
+          end)
+        end
+      end
+
+      def remove_deleted_from_index(_), do: nil
+
       @impl OrderedCache
       def update(elements) when is_nil(elements), do: :ok
 
@@ -217,7 +230,8 @@ defmodule Explorer.Chain.OrderedCache do
             |> Enum.sort(&prevails?(&1, &2))
             |> merge_and_update(ids || [], max_size())
 
-          {:ok, updated_list}
+          # ids_list is set to never expire
+          {:ok, %ConCache.Item{value: updated_list, ttl: :infinity}}
         end)
       end
 
@@ -308,7 +322,21 @@ defmodule Explorer.Chain.OrderedCache do
       provided to this function will override the ones set by using the macro
       """
       def child_spec(params) do
-        params = Keyword.merge(unquote(concache_params), params)
+        # params specified in `use`
+        merged_params =
+          unquote(concache_params)
+          # params specified in `child_spec`
+          |> Keyword.merge(params)
+          # `:ttl_check_interval` needs to be specified, defaults to `false`
+          |> Keyword.put_new(:ttl_check_interval, false)
+
+        # if `:ttl_check_interval` is not `false` the expired values need to be
+        # removed from the cache's index
+        params =
+          case merged_params[:ttl_check_interval] do
+            false -> merged_params
+            _ -> Keyword.put_new(merged_params, :callback, &remove_deleted_from_index/1)
+          end
 
         Supervisor.child_spec({ConCache, params}, id: child_id())
       end
diff --git a/apps/explorer/test/explorer/chain/cache/block_number_test.exs b/apps/explorer/test/explorer/chain/cache/block_number_test.exs
index 64170695eb..87107fe45c 100644
--- a/apps/explorer/test/explorer/chain/cache/block_number_test.exs
+++ b/apps/explorer/test/explorer/chain/cache/block_number_test.exs
@@ -11,7 +11,7 @@ defmodule Explorer.Chain.Cache.BlockNumberTest do
     end)
   end
 
-  describe "get_max/1" do
+  describe "get_max/0" do
     test "returns max number" do
       insert(:block, number: 5)
 
@@ -19,7 +19,7 @@ defmodule Explorer.Chain.Cache.BlockNumberTest do
     end
   end
 
-  describe "get_min/1" do
+  describe "get_min/0" do
     test "returns min number" do
       insert(:block, number: 2)
 
@@ -27,7 +27,7 @@ defmodule Explorer.Chain.Cache.BlockNumberTest do
     end
   end
 
-  describe "get_all/1" do
+  describe "get_all/0" do
     test "returns min and max number" do
       insert(:block, number: 6)