mempool/backend/src/api/projected-blocks.ts
2019-10-28 16:47:42 +08:00

103 lines
3.6 KiB
TypeScript

const config = require('../../mempool-config.json');
import { ITransaction, IProjectedBlock, IMempool, IProjectedBlockInternal } from '../interfaces';
class ProjectedBlocks {
private transactionsSorted: ITransaction[] = [];
constructor() {}
public getProjectedBlockFeesForBlock(index: number) {
const projectedBlock = this.getProjectedBlocksInternal()[index];
if (!projectedBlock) {
throw new Error('No projected block for that index');
}
return projectedBlock.txFeePerVsizes.map((fpv) => {
return {'fpv': fpv};
});
}
public updateProjectedBlocks(memPool: IMempool): void {
const latestMempool = memPool;
const memPoolArray: ITransaction[] = [];
for (const i in latestMempool) {
if (latestMempool.hasOwnProperty(i)) {
memPoolArray.push(latestMempool[i]);
}
}
memPoolArray.sort((a, b) => b.feePerWeightUnit - a.feePerWeightUnit);
this.transactionsSorted = memPoolArray.filter((tx) => tx.feePerWeightUnit);
}
public getProjectedBlocks(txId?: string, numberOfBlocks: number = config.DEFAULT_PROJECTED_BLOCKS_AMOUNT): IProjectedBlock[] {
return this.getProjectedBlocksInternal(numberOfBlocks).map((projectedBlock) => {
return {
blockSize: projectedBlock.blockSize,
blockWeight: projectedBlock.blockWeight,
nTx: projectedBlock.nTx,
minFee: projectedBlock.minFee,
maxFee: projectedBlock.maxFee,
minWeightFee: projectedBlock.minWeightFee,
maxWeightFee: projectedBlock.maxWeightFee,
medianFee: projectedBlock.medianFee,
fees: projectedBlock.fees,
hasMytx: txId ? projectedBlock.txIds.some((tx) => tx === txId) : false
};
});
}
private getProjectedBlocksInternal(numberOfBlocks: number = config.DEFAULT_PROJECTED_BLOCKS_AMOUNT): IProjectedBlockInternal[] {
const projectedBlocks: IProjectedBlockInternal[] = [];
let blockWeight = 0;
let blockSize = 0;
let transactions: ITransaction[] = [];
this.transactionsSorted.forEach((tx) => {
if (blockWeight + tx.vsize * 4 < 4000000 || projectedBlocks.length === numberOfBlocks) {
blockWeight += tx.weight || tx.vsize * 4;
blockSize += tx.size;
transactions.push(tx);
} else {
projectedBlocks.push(this.dataToProjectedBlock(transactions, blockSize, blockWeight));
blockWeight = 0;
blockSize = 0;
transactions = [];
}
});
if (transactions.length) {
projectedBlocks.push(this.dataToProjectedBlock(transactions, blockSize, blockWeight));
}
return projectedBlocks;
}
private dataToProjectedBlock(transactions: ITransaction[], blockSize: number, blockWeight: number): IProjectedBlockInternal {
return {
blockSize: blockSize,
blockWeight: blockWeight,
nTx: transactions.length,
minFee: transactions[transactions.length - 1].feePerVsize,
maxFee: transactions[0].feePerVsize,
minWeightFee: transactions[transactions.length - 1].feePerWeightUnit,
maxWeightFee: transactions[0].feePerWeightUnit,
medianFee: this.median(transactions.map((tx) => tx.feePerVsize)),
txIds: transactions.map((tx) => tx.txid),
txFeePerVsizes: transactions.map((tx) => tx.feePerVsize).reverse(),
fees: transactions.map((tx) => tx.fee).reduce((acc, currValue) => acc + currValue),
};
}
private median(numbers: number[]) {
let medianNr = 0;
const numsLen = numbers.length;
numbers.sort();
if (numsLen % 2 === 0) {
medianNr = (numbers[numsLen / 2 - 1] + numbers[numsLen / 2]) / 2;
} else {
medianNr = numbers[(numsLen - 1) / 2];
}
return medianNr;
}
}
export default new ProjectedBlocks();