From 281899f5514417224be4275873b4804a3323dd7e Mon Sep 17 00:00:00 2001
From: nymkappa <1612910616@pm.me>
Date: Sat, 18 Feb 2023 14:10:07 +0900
Subject: [PATCH] List orphaned blocks in the new blocks-bulk API

---
 backend/src/api/blocks.ts         |  8 ++++-
 backend/src/api/chain-tips.ts     | 53 +++++++++++++++++++++++++++++++
 backend/src/index.ts              |  2 ++
 backend/src/mempool.interfaces.ts |  3 +-
 4 files changed, 64 insertions(+), 2 deletions(-)
 create mode 100644 backend/src/api/chain-tips.ts

diff --git a/backend/src/api/blocks.ts b/backend/src/api/blocks.ts
index ccf7bd2f4..25c199de9 100644
--- a/backend/src/api/blocks.ts
+++ b/backend/src/api/blocks.ts
@@ -25,6 +25,7 @@ import mining from './mining/mining';
 import DifficultyAdjustmentsRepository from '../repositories/DifficultyAdjustmentsRepository';
 import PricesRepository from '../repositories/PricesRepository';
 import priceUpdater from '../tasks/price-updater';
+import chainTips from './chain-tips';
 
 class Blocks {
   private blocks: BlockExtended[] = [];
@@ -171,6 +172,7 @@ class Blocks {
     blk.extras.coinbaseRaw = blk.extras.coinbaseTx.vin[0].scriptsig;
     blk.extras.usd = priceUpdater.latestPrices.USD;
     blk.extras.medianTimestamp = block.medianTime;
+    blk.extras.orphans = chainTips.getOrphanedBlocksAtHeight(blk.height);
 
     if (block.height === 0) {
       blk.extras.medianFee = 0; // 50th percentiles
@@ -204,7 +206,6 @@ class Blocks {
     }
 
     blk.extras.blockTime = 0; // TODO
-    blk.extras.orphaned = false; // TODO
 
     blk.extras.feePercentiles = await BlocksSummariesRepository.$getFeePercentilesByBlockId(block.id);
     if (blk.extras.feePercentiles !== null) {
@@ -545,6 +546,7 @@ class Blocks {
       } else {
         this.currentBlockHeight++;
         logger.debug(`New block found (#${this.currentBlockHeight})!`);
+        await chainTips.updateOrphanedBlocks();
       }
 
       const blockHash = await bitcoinApi.$getBlockHash(this.currentBlockHeight);
@@ -812,6 +814,10 @@ class Blocks {
         }
       }
 
+      // Re-org can happen after indexing so we need to always get the
+      // latest state from core
+      block.orphans = chainTips.getOrphanedBlocksAtHeight(block.height);
+
       blocks.push(block);
       fromHeight++;
     }
diff --git a/backend/src/api/chain-tips.ts b/backend/src/api/chain-tips.ts
new file mode 100644
index 000000000..5b0aa8a5c
--- /dev/null
+++ b/backend/src/api/chain-tips.ts
@@ -0,0 +1,53 @@
+import logger from "../logger";
+import bitcoinClient from "./bitcoin/bitcoin-client";
+
+export interface ChainTip {
+  height: number;
+  hash: string;
+  branchlen: number;
+  status: 'invalid' | 'active' | 'valid-fork' | 'valid-headers' | 'headers-only';
+};
+
+export interface OrphanedBlock {
+  height: number;
+  hash: string;
+  status: 'valid-fork' | 'valid-headers' | 'headers-only';
+}
+
+class ChainTips {
+  private chainTips: ChainTip[] = [];
+  private orphanedBlocks: OrphanedBlock[] = [];
+
+  public async updateOrphanedBlocks(): Promise<void> {
+    this.chainTips = await bitcoinClient.getChainTips();
+    this.orphanedBlocks = [];
+
+    for (const chain of this.chainTips) {
+      if (chain.status === 'valid-fork' || chain.status === 'valid-headers' || chain.status === 'headers-only') {
+        let block = await bitcoinClient.getBlock(chain.hash);
+        while (block && block.confirmations === -1) {
+          this.orphanedBlocks.push({
+            height: block.height,
+            hash: block.hash,
+            status: chain.status
+          });
+          block = await bitcoinClient.getBlock(block.previousblockhash);
+        }
+      }
+    }
+
+    logger.debug(`Updated orphaned blocks cache. Found ${this.orphanedBlocks.length} orphaned blocks`);
+  }
+
+  public getOrphanedBlocksAtHeight(height: number): OrphanedBlock[] {
+    const orphans: OrphanedBlock[] = [];
+    for (const block of this.orphanedBlocks) {
+      if (block.height === height) {
+        orphans.push(block);
+      }
+    }
+    return orphans;
+  }
+}
+
+export default new ChainTips();
\ No newline at end of file
diff --git a/backend/src/index.ts b/backend/src/index.ts
index d8d46fc9f..6ea3ddc43 100644
--- a/backend/src/index.ts
+++ b/backend/src/index.ts
@@ -37,6 +37,7 @@ import fundingTxFetcher from './tasks/lightning/sync-tasks/funding-tx-fetcher';
 import forensicsService from './tasks/lightning/forensics.service';
 import priceUpdater from './tasks/price-updater';
 import mining from './api/mining/mining';
+import chainTips from './api/chain-tips';
 import { AxiosError } from 'axios';
 
 class Server {
@@ -134,6 +135,7 @@ class Server {
     }
 
     priceUpdater.$run();
+    await chainTips.updateOrphanedBlocks();
 
     this.setUpHttpApiRoutes();
 
diff --git a/backend/src/mempool.interfaces.ts b/backend/src/mempool.interfaces.ts
index a7e7c4ec6..e139bde8f 100644
--- a/backend/src/mempool.interfaces.ts
+++ b/backend/src/mempool.interfaces.ts
@@ -1,4 +1,5 @@
 import { IEsploraApi } from './api/bitcoin/esplora-api.interface';
+import { OrphanedBlock } from './api/chain-tips';
 import { HeapNode } from "./utils/pairing-heap";
 
 export interface PoolTag {
@@ -163,7 +164,7 @@ export interface BlockExtension {
   usd?: number | null;
   medianTimestamp?: number;
   blockTime?: number;
-  orphaned?: boolean;
+  orphans?: OrphanedBlock[] | null;
   coinbaseAddress?: string | null;
   coinbaseSignature?: string | null;
   virtualSize?: number;