indexer: index the genesis block

lib/indexer/indexer.js

@@ -15,6 +15,8 @@ const Logger = require('blgr');
 const Network = require('../protocol/network');
 const util = require('../utils/util');
 const layout = require('./layout');
+const CoinView = require('../coins/coinview');
+const Block = require('../primitives/block');
 const {ZERO_HASH} = require('../protocol/consensus');
 
 /**
@@ -111,6 +113,8 @@ class Indexer extends EventEmitter {
     const data = await this.db.get(layout.R.encode());
     if (data)
       this.height = bio.readU32(data, 0);
+    else
+      await this.saveGenesis();
 
     // Bind to chain events.
     this.bind();
@@ -160,6 +164,27 @@ class Indexer extends EventEmitter {
       throw new Error('Indexer: Network mismatch.');
   }
 
+  /**
+   * A special case for indexing the genesis block. The genesis
+   * block coins are not spendable, however indexers can still index
+   * the block for historical and informational purposes.
+   * @private
+   * @returns {Promise}
+   */
+
+  async saveGenesis() {
+    this.start();
+
+    const block = Block.fromRaw(Buffer.from(this.network.genesisBlock, 'hex'));
+    const meta = new BlockMeta(block.hash(), 0);
+
+    await this.indexBlock(meta, block, new CoinView());
+    await this._setTip(meta);
+    await this.commit();
+
+    this.height = 0;
+  }
+
   /**
    * Bind to chain events.
    * @private

test/indexer-test.js

@@ -8,6 +8,7 @@ const reorg = require('./util/reorg');
 const Script = require('../lib/script/script');
 const Opcode = require('../lib/script/opcode');
 const Address = require('../lib/primitives/address');
+const Block = require('../lib/primitives/block');
 const Chain = require('../lib/blockchain/chain');
 const WorkerPool = require('../lib/workers/workerpool');
 const Miner = require('../lib/mining/miner');
@@ -306,6 +307,21 @@ describe('Indexer', function() {
       assert.strictEqual(tx, null);
       assert.strictEqual(meta, null);
     });
+
+    it('should get unspendable genesis tx', async () => {
+      const block = Block.fromRaw(Buffer.from(network.genesisBlock, 'hex'));
+      const hash = block.txs[0].hash();
+
+      const tx = await txindexer.getTX(hash);
+      const meta = await txindexer.getMeta(hash);
+
+      assert(meta);
+      assert.equal(meta.height, 0);
+      assert(meta.block);
+      assert(meta.time);
+
+      assert.deepEqual(meta.tx, tx);
+    });
   });
 
   describe('Reorg and rescan', function() {