You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
57 lines
1.2 KiB
57 lines
1.2 KiB
6 years ago
|
/*!
|
||
|
|
* lib/bitcoind-rpc/headers.js
|
||
|
|
* Copyright © 2019 – Katana Cryptographic Ltd. All Rights Reserved.
|
||
|
|
*/
|
||
|
|
'use strict'
|
||
|
|
|
||
|
|
const LRU = require('lru-cache')
|
||
|
|
const errors = require('../errors')
|
||
|
|
const RpcClient = require('./rpc-client')
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* A singleton providing information about block headers
|
||
|
|
*/
|
||
|
|
class Headers {
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Constructor
|
||
|
|
*/
|
||
|
|
constructor() {
|
||
|
|
// Cache
|
||
|
|
this.headers = LRU({
|
||
|
|
// Maximum number of headers to store in cache
|
||
|
|
max: 2016,
|
||
|
|
// Function used to compute length of item
|
||
|
|
length: (n, key) => 1,
|
||
|
|
// Maximum age for items in the cache. Items do not expire
|
||
|
|
maxAge: Infinity
|
||
|
|
})
|
||
|
|
|
||
|
|
// Initialize the rpc client
|
||
|
|
this.rpcClient = new RpcClient()
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Get the block header for a given hash
|
||
|
|
* @param {string} hash - block hash
|
||
|
|
* @returns {Promise}
|
||
|
|
*/
|
||
|
|
async getHeader(hash) {
|
||
|
|
if (this.headers.has(hash))
|
||
|
|
return this.headers.get(hash)
|
||
|
|
|
||
|
|
try {
|
||
|
|
const header = await this.rpcClient.getblockheader(hash, true)
|
||
|
|
const fmtHeader = JSON.stringify(header, null, 2)
|
||
|
|
this.headers.set(hash, fmtHeader)
|
||
|
|
return fmtHeader
|
||
|
|
} catch(e) {
|
||
|
|
return Promise.reject(errors.generic.GEN)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
module.exports = new Headers()
|