Add possibility to add extra headers with RPC URL

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Features
 
+- [#7898](https://github.com/blockscout/blockscout/pull/7898) - Add possibility to add extra headers with JSON RPC URL
 - [#7836](https://github.com/blockscout/blockscout/pull/7836) - Improve unverified email flow
 - [#7784](https://github.com/blockscout/blockscout/pull/7784) - Search improvements: Add new fields, light refactoring
 - [#7811](https://github.com/blockscout/blockscout/pull/7811) - Filter addresses before insertion

apps/ethereum_jsonrpc/lib/ethereum_jsonrpc/http.ex

@@ -14,7 +14,7 @@ defmodule EthereumJSONRPC.HTTP do
   @doc """
   Sends JSONRPC request encoded as `t:iodata/0` to `url` with `options`
   """
-  @callback json_rpc(url :: String.t(), json :: iodata(), options :: term()) ::
+  @callback json_rpc(url :: String.t(), json :: iodata(), headers :: [{String.t(), String.t()}], options :: term()) ::
               {:ok, %{body: body :: String.t(), status_code: status_code :: pos_integer()}}
               | {:error, reason :: term}
 
@@ -26,7 +26,7 @@ defmodule EthereumJSONRPC.HTTP do
     url = url(options, method)
     http_options = Keyword.fetch!(options, :http_options)
 
-    with {:ok, %{body: body, status_code: code}} <- http.json_rpc(url, json, http_options),
+    with {:ok, %{body: body, status_code: code}} <- http.json_rpc(url, json, headers(), http_options),
          {:ok, json} <- decode_json(request: [url: url, body: json], response: [status_code: code, body: body]),
          {:ok, response} <- handle_response(json, code) do
       {:ok, response}
@@ -66,7 +66,7 @@ defmodule EthereumJSONRPC.HTTP do
 
     json = encode_json(batch)
 
-    case http.json_rpc(url, json, http_options) do
+    case http.json_rpc(url, json, headers(), http_options) do
       {:ok, %{status_code: status_code} = response} when status_code in [413, 504] ->
         rechunk_json_rpc(chunks, options, response, decoded_response_bodies)
 
@@ -203,4 +203,8 @@ defmodule EthereumJSONRPC.HTTP do
     ArgumentError ->
       :error
   end
+
+  defp headers do
+    Application.get_env(:ethereum_jsonrpc, __MODULE__)[:headers]
+  end
 end

apps/ethereum_jsonrpc/lib/ethereum_jsonrpc/http/httpoison.ex

@@ -8,8 +8,8 @@ defmodule EthereumJSONRPC.HTTP.HTTPoison do
   @behaviour HTTP
 
   @impl HTTP
-  def json_rpc(url, json, options) when is_binary(url) and is_list(options) do
+  def json_rpc(url, json, headers, options) when is_binary(url) and is_list(options) do
-    case HTTPoison.post(url, json, [{"Content-Type", "application/json"}], options) do
+    case HTTPoison.post(url, json, headers, options) do
       {:ok, %HTTPoison.Response{body: body, status_code: status_code}} ->
         {:ok, %{body: body, status_code: status_code}}
 
@@ -18,5 +18,5 @@ defmodule EthereumJSONRPC.HTTP.HTTPoison do
     end
   end
 
-  def json_rpc(url, _json, _options) when is_nil(url), do: {:error, "URL is nil"}
+  def json_rpc(url, _json, _headers, _options) when is_nil(url), do: {:error, "URL is nil"}
 end

apps/ethereum_jsonrpc/test/ethereum_jsonrpc/http/mox_test.exs

@@ -38,12 +38,12 @@ defmodule EthereumJSONRPC.HTTP.MoxTest do
     } do
       if json_rpc_named_arguments[:transport_options][:http] == EthereumJSONRPC.HTTP.Mox do
         EthereumJSONRPC.HTTP.Mox
-        |> expect(:json_rpc, 2, fn _url, json, _options ->
+        |> expect(:json_rpc, 2, fn _url, json, _headers, _options ->
           assert IO.iodata_to_binary(json) =~ ":13000"
 
           {:ok, %{body: "413 Request Entity Too Large", status_code: 413}}
         end)
-        |> expect(:json_rpc, fn _url, json, _options ->
+        |> expect(:json_rpc, fn _url, json, _headers, _options ->
           json_binary = IO.iodata_to_binary(json)
 
           refute json_binary =~ ":13000"
@@ -58,7 +58,7 @@ defmodule EthereumJSONRPC.HTTP.MoxTest do
 
           {:ok, %{body: body, status_code: 200}}
         end)
-        |> expect(:json_rpc, fn _url, json, _options ->
+        |> expect(:json_rpc, fn _url, json, _headers, _options ->
           json_binary = IO.iodata_to_binary(json)
 
           refute json_binary =~ ":6499"
@@ -107,10 +107,10 @@ defmodule EthereumJSONRPC.HTTP.MoxTest do
 
       if json_rpc_named_arguments[:transport_options][:http] == EthereumJSONRPC.HTTP.Mox do
         EthereumJSONRPC.HTTP.Mox
-        |> expect(:json_rpc, fn _url, _json, _options ->
+        |> expect(:json_rpc, fn _url, _json, _headers, _options ->
           {:ok, %{body: "504 Gateway Timeout", status_code: 504}}
         end)
-        |> expect(:json_rpc, fn _url, json, _options ->
+        |> expect(:json_rpc, fn _url, json, _headers, _options ->
           json_binary = IO.iodata_to_binary(json)
 
           refute json_binary =~ "0xD2849"
@@ -141,7 +141,7 @@ defmodule EthereumJSONRPC.HTTP.MoxTest do
 
           {:ok, %{body: body, status_code: 200}}
         end)
-        |> expect(:json_rpc, fn _url, json, _options ->
+        |> expect(:json_rpc, fn _url, json, _headers, _options ->
           json_binary = IO.iodata_to_binary(json)
 
           refute json_binary =~ "0xD2844"
@@ -199,10 +199,10 @@ defmodule EthereumJSONRPC.HTTP.MoxTest do
 
       if json_rpc_named_arguments[:transport_options][:http] == EthereumJSONRPC.HTTP.Mox do
         EthereumJSONRPC.HTTP.Mox
-        |> expect(:json_rpc, fn _url, _json, _options ->
+        |> expect(:json_rpc, fn _url, _json, _headers, _options ->
           {:error, :timeout}
         end)
-        |> expect(:json_rpc, fn _url, json, _options ->
+        |> expect(:json_rpc, fn _url, json, _headers, _options ->
           json_binary = IO.iodata_to_binary(json)
 
           refute json_binary =~ "0xD2849"
@@ -233,7 +233,7 @@ defmodule EthereumJSONRPC.HTTP.MoxTest do
 
           {:ok, %{body: body, status_code: 200}}
         end)
-        |> expect(:json_rpc, fn _url, json, _options ->
+        |> expect(:json_rpc, fn _url, json, _headers, _options ->
           json_binary = IO.iodata_to_binary(json)
 
           refute json_binary =~ "0xD2844"
@@ -293,7 +293,7 @@ defmodule EthereumJSONRPC.HTTP.MoxTest do
     json = Jason.encode_to_iodata!(payload)
     http_options = Keyword.fetch!(transport_options, :http_options)
 
-    assert {:ok, %{body: body, status_code: 413}} = http.json_rpc(url, json, http_options)
+    assert {:ok, %{body: body, status_code: 413}} = http.json_rpc(url, json, [], http_options)
     assert body =~ "413 Request Entity Too Large"
   end
 

config/config_helper.exs

@@ -119,4 +119,13 @@ defmodule ConfigHelper do
         transformer
     end
   end
+
+  @spec parse_json_env_var(String.t(), String.t()) :: any()
+  def parse_json_env_var(env_var, default_value) do
+    env_var
+    |> safe_get_env(default_value)
+    |> Jason.decode!()
+  rescue
+    err -> raise "Invalid JSON in environment variable #{env_var}: #{inspect(err)}"
+  end
 end

config/runtime.exs

@@ -150,6 +150,12 @@ config :ethereum_jsonrpc,
   ipc_path: System.get_env("IPC_PATH"),
   disable_archive_balances?: ConfigHelper.parse_bool_env_var("ETHEREUM_JSONRPC_DISABLE_ARCHIVE_BALANCES")
 
+config :ethereum_jsonrpc, EthereumJSONRPC.HTTP,
+  headers:
+    %{"Content-Type" => "application/json"}
+    |> Map.merge(ConfigHelper.parse_json_env_var("ETHEREUM_JSONRPC_HTTP_HEADERS", "{}"))
+    |> Map.to_list()
+
 config :ethereum_jsonrpc, EthereumJSONRPC.Geth,
   debug_trace_transaction_timeout: System.get_env("ETHEREUM_JSONRPC_DEBUG_TRACE_TRANSACTION_TIMEOUT", "5s"),
   tracer: System.get_env("INDEXER_INTERNAL_TRANSACTIONS_TRACER_TYPE", "call_tracer")

docker-compose/envs/common-blockscout.env

@@ -12,6 +12,7 @@ LOGO=/images/blockscout_logo.svg
 # ETHEREUM_JSONRPC_WS_URL=
 ETHEREUM_JSONRPC_TRANSPORT=http
 ETHEREUM_JSONRPC_DISABLE_ARCHIVE_BALANCES=false
+# ETHEREUM_JSONRPC_HTTP_HEADERS=
 IPC_PATH=
 NETWORK_PATH=/
 BLOCKSCOUT_HOST=

docker/Makefile

@@ -60,6 +60,9 @@ endif
 ifdef ETHEREUM_JSONRPC_DISABLE_ARCHIVE_BALANCES
 	BLOCKSCOUT_CONTAINER_PARAMS += -e 'ETHEREUM_JSONRPC_DISABLE_ARCHIVE_BALANCES=$(ETHEREUM_JSONRPC_DISABLE_ARCHIVE_BALANCES)'
 endif
+ifdef ETHEREUM_JSONRPC_HTTP_HEADERS
+	BLOCKSCOUT_CONTAINER_PARAMS += -e 'ETHEREUM_JSONRPC_HTTP_HEADERS=$(ETHEREUM_JSONRPC_HTTP_HEADERS)'
+endif
 ifdef IPC_PATH
 	BLOCKSCOUT_CONTAINER_PARAMS += -e 'IPC_PATH=$(IPC_PATH)'
 endif