Refactored transaction handling.

backend/src/api/transaction-utils.ts

@@ -0,0 +1,124 @@
+import bitcoinApi from './bitcoin/bitcoin-api-factory';
+import { MempoolEntries, MempoolEntry, Transaction, TransactionExtended, TransactionMinerInfo } from '../interfaces';
+import config from '../config';
+import logger from '../logger';
+import mempool from './mempool';
+import blocks from './blocks';
+
+class TransactionUtils {
+  private mempoolEntriesCache: MempoolEntries | null = null;
+
+  constructor() { }
+
+  public async $addPrevoutsToTransaction(transaction: TransactionExtended): Promise<TransactionExtended> {
+    for (const vin of transaction.vin) {
+      const innerTx = await bitcoinApi.$getRawTransaction(vin.txid);
+      vin.prevout = innerTx.vout[vin.vout];
+    }
+    return transaction;
+  }
+
+  public async $calculateFeeFromInputs(transaction: Transaction): Promise<TransactionExtended> {
+    if (transaction.vin[0]['coinbase']) {
+      transaction.fee = 0;
+      // @ts-ignore
+      return transaction;
+    }
+    let totalIn = 0;
+    for (const vin of transaction.vin) {
+      const innerTx = await bitcoinApi.$getRawTransaction(vin.txid);
+      totalIn += innerTx.vout[vin.vout].value;
+    }
+    const totalOut = transaction.vout.reduce((prev, output) => prev + output.value, 0);
+    transaction.fee = parseFloat((totalIn - totalOut).toFixed(8));
+    return this.extendTransaction(transaction);
+  }
+
+  public extendTransaction(transaction: Transaction | MempoolEntry): TransactionExtended {
+    // @ts-ignore
+    return Object.assign({
+      vsize: Math.round(transaction.weight / 4),
+      feePerVsize: Math.max(1, (transaction.fee || 0) / (transaction.weight / 4)),
+      firstSeen: Math.round((new Date().getTime() / 1000)),
+    }, transaction);
+  }
+
+  public stripCoinbaseTransaction(tx: TransactionExtended): TransactionMinerInfo {
+    return {
+      vin: [{
+        scriptsig: tx.vin[0].scriptsig || tx.vin[0]['coinbase']
+      }],
+      vout: tx.vout
+        .map((vout) => ({
+          scriptpubkey_address: vout.scriptpubkey_address,
+          value: vout.value
+        }))
+        .filter((vout) => vout.value)
+    };
+  }
+
+  public async getTransactionExtended(txId: string, isCoinbase = false, inMempool = false): Promise<TransactionExtended | null> {
+    try {
+      let transaction: Transaction;
+      if (inMempool) {
+        transaction = await bitcoinApi.$getRawTransactionBitcond(txId);
+      } else {
+        transaction = await bitcoinApi.$getRawTransaction(txId);
+      }
+      if (config.MEMPOOL.BACKEND !== 'electrs' && !isCoinbase) {
+        if (inMempool) {
+          transaction = await this.$appendFeeData(transaction);
+        } else {
+          transaction = await this.$calculateFeeFromInputs(transaction);
+        }
+      }
+      return this.extendTransaction(transaction);
+    } catch (e) {
+      logger.debug('getTransactionExtended error: ' + (e.message || e));
+      console.log(e);
+      return null;
+    }
+  }
+
+  public bitcoindToElectrsTransaction(transaction: any): void {
+    try {
+      transaction.vout = transaction.vout.map((vout) => {
+        return {
+          value: vout.value * 100000000,
+          scriptpubkey: vout.scriptPubKey.hex,
+          scriptpubkey_address: vout.scriptPubKey && vout.scriptPubKey.addresses ? vout.scriptPubKey.addresses[0] : null,
+          scriptpubkey_asm: vout.scriptPubKey.asm,
+          scriptpubkey_type: vout.scriptPubKey.type,
+        };
+      });
+      if (transaction.confirmations) {
+        transaction['status'] = {
+          confirmed: true,
+          block_height: blocks.getCurrentBlockHeight() - transaction.confirmations,
+          block_hash: transaction.blockhash,
+          block_time: transaction.blocktime,
+        };
+      } else {
+        transaction['status'] = { confirmed: false };
+      }
+    } catch (e) {
+      console.log('augment failed: ' + (e.message || e));
+    }
+  }
+
+  private async $appendFeeData(transaction: Transaction): Promise<Transaction> {
+    let mempoolEntry: MempoolEntry;
+    if (!mempool.isInSync() && !this.mempoolEntriesCache) {
+      this.mempoolEntriesCache = await bitcoinApi.$getRawMempoolVerbose();
+    }
+    if (this.mempoolEntriesCache && this.mempoolEntriesCache[transaction.txid]) {
+      mempoolEntry = this.mempoolEntriesCache[transaction.txid];
+    } else {
+      mempoolEntry = await bitcoinApi.$getMempoolEntry(transaction.txid);
+    }
+    transaction.fee = mempoolEntry.fees.base * 100000000;
+    return transaction;
+  }
+}
+
+export default new TransactionUtils();