From 875e5061489a1c514985b482a53d455d5db2bea2 Mon Sep 17 00:00:00 2001
From: Austin Roberts <austin.roberts@openrelay.xyz>
Date: Mon, 12 Jul 2021 11:38:52 -0500
Subject: [PATCH] Invoke plugins when blocks are added as new heads or
 sidechain blocks

---
 core/blockchain.go   |  2 ++
 core/plugin_hooks.go | 40 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 42 insertions(+)

diff --git a/core/blockchain.go b/core/blockchain.go
index 18e126657..79e2da4aa 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -1566,6 +1566,7 @@ func (bc *BlockChain) writeBlockWithState(block *types.Block, receipts []*types.
 	bc.futureBlocks.Remove(block.Hash())
 
 	if status == CanonStatTy {
+		pluginNewHead(block, block.Hash(), logs)
 		bc.chainFeed.Send(ChainEvent{Block: block, Hash: block.Hash(), Logs: logs})
 		if len(logs) > 0 {
 			bc.logsFeed.Send(logs)
@@ -1579,6 +1580,7 @@ func (bc *BlockChain) writeBlockWithState(block *types.Block, receipts []*types.
 			bc.chainHeadFeed.Send(ChainHeadEvent{Block: block})
 		}
 	} else {
+		pluginNewSideBlock(block, block.Hash(), logs)
 		bc.chainSideFeed.Send(ChainSideEvent{Block: block})
 	}
 	return status, nil
diff --git a/core/plugin_hooks.go b/core/plugin_hooks.go
index 7cc480772..4c20f1320 100644
--- a/core/plugin_hooks.go
+++ b/core/plugin_hooks.go
@@ -2,6 +2,7 @@ package core
 
 import (
   "github.com/ethereum/go-ethereum/core/types"
+  "github.com/ethereum/go-ethereum/common"
   "github.com/ethereum/go-ethereum/plugins"
   "github.com/ethereum/go-ethereum/log"
 )
@@ -96,3 +97,42 @@ func pluginPostProcessBlock(block *types.Block) {
   }
   PluginPostProcessBlock(plugins.DefaultPluginLoader, block)
 }
+
+
+func PluginNewHead(pl *plugins.PluginLoader, block *types.Block, hash common.Hash, logs []*types.Log) {
+  fnList := pl.Lookup("NewHead", func(item interface{}) bool {
+    _, ok := item.(func(*types.Block, common.Hash, []*types.Log))
+    return ok
+  })
+  for _, fni := range fnList {
+    if fn, ok := fni.(func(*types.Block, common.Hash, []*types.Log)); ok {
+      fn(block, hash, logs)
+    }
+  }
+}
+func pluginNewHead(block *types.Block, hash common.Hash, logs []*types.Log) {
+  if plugins.DefaultPluginLoader == nil {
+		log.Warn("Attempting NewHead, but default PluginLoader has not been initialized")
+    return
+  }
+  PluginNewHead(plugins.DefaultPluginLoader, block, hash, logs)
+}
+
+func PluginNewSideBlock(pl *plugins.PluginLoader, block *types.Block, hash common.Hash, logs []*types.Log) {
+  fnList := pl.Lookup("NewSideBlock", func(item interface{}) bool {
+    _, ok := item.(func(*types.Block, common.Hash, []*types.Log))
+    return ok
+  })
+  for _, fni := range fnList {
+    if fn, ok := fni.(func(*types.Block, common.Hash, []*types.Log)); ok {
+      fn(block, hash, logs)
+    }
+  }
+}
+func pluginNewSideBlock(block *types.Block, hash common.Hash, logs []*types.Log) {
+  if plugins.DefaultPluginLoader == nil {
+		log.Warn("Attempting NewSideBlock, but default PluginLoader has not been initialized")
+    return
+  }
+  PluginNewSideBlock(plugins.DefaultPluginLoader, block, hash, logs)
+}