From 665ca53d3278a7c06e9cb17b6c01507d08fc8896 Mon Sep 17 00:00:00 2001
From: Wen Chen <wchen@forte.io>
Date: Tue, 2 Apr 2024 09:46:05 -0400
Subject: [PATCH] get max_priority_fee

---
 CHANGELOG.md         |  6 ++++++
 lib/ethers.ex        | 17 +++++++++++++++--
 test/ethers_test.exs |  6 ++++++
 3 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4d6fd0a..305b031 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
 # Changelog
 
+## Unreleased
+
+### Enhancements
+
+- Add support of getting current `max_priority_fee_per_gas`.
+
 ## v0.4.0 (2024-03-11)
 
 ### Breaking Changes
diff --git a/lib/ethers.ex b/lib/ethers.ex
index 802f470..a0d99f3 100644
--- a/lib/ethers.ex
+++ b/lib/ethers.ex
@@ -70,10 +70,11 @@ defmodule Ethers do
 
   @option_keys [:rpc_client, :rpc_opts, :signer, :signer_opts, :tx_type]
   @hex_decode_post_process [
-    :estimate_gas,
     :current_gas_price,
     :current_block_number,
-    :get_balance
+    :estimate_gas,
+    :get_balance,
+    :max_priority_fee_per_gas
   ]
   @rpc_actions_map %{
     call: :eth_call,
@@ -85,6 +86,7 @@ defmodule Ethers do
     get_logs: :eth_get_logs,
     get_transaction_count: :eth_get_transaction_count,
     get_transaction: :eth_get_transaction_by_hash,
+    max_priority_fee_per_gas: :eth_max_priority_fee_per_gas,
     send: :eth_send_transaction
   }
 
@@ -414,6 +416,17 @@ defmodule Ethers do
     end
   end
 
+  @doc """
+  Returns the current max priority fee per gas from the RPC API
+  """
+  @spec max_priority_fee_per_gas(Keyword.t()) :: {:ok, non_neg_integer()}
+  def max_priority_fee_per_gas(opts \\ []) do
+    {rpc_client, rpc_opts} = get_rpc_client(opts)
+
+    rpc_client.eth_max_priority_fee_per_gas(rpc_opts)
+    |> post_process(nil, :max_priority_fee_per_gas)
+  end
+
   @doc """
   Fetches the event logs with the given filter.
 
diff --git a/test/ethers_test.exs b/test/ethers_test.exs
index 741a5c5..ac16670 100644
--- a/test/ethers_test.exs
+++ b/test/ethers_test.exs
@@ -27,6 +27,12 @@ defmodule EthersTest do
     end
   end
 
+  describe "max_priority_fee_per_gas" do
+    test "returns the correct max priority fee per gas" do
+      assert {:ok, 1_000_000_000} = Ethers.max_priority_fee_per_gas()
+    end
+  end
+
   describe "current_block_number" do
     test "returns the current block number" do
       assert {:ok, n} = Ethers.current_block_number()