add more utility functions and improved tests

src/xrpIO/xrpl-binding.ts

@@ -3,14 +3,18 @@ import { Client, Payment, TxResponse, Wallet } from 'xrpl'
 
 import * as zlib from 'zlib'
 import * as util from 'util'
+import { NON_ZERO_TX_HASH } from '../util/protocol.constants'
+import { ERR_BAD_TX_HASH } from '../util/errors'
 
 const compressB64 = async (data: string) => (await util.promisify(zlib.deflate)(Buffer.from(data, 'utf-8'))).toString('base64')
 const decompressB64 = async (data: string) => (await util.promisify(zlib.inflate)(Buffer.from(data, 'base64'))).toString('utf-8')
 const hexDecode = (str: string) => Buffer.from(str, 'hex').toString('utf8')
 const hexEncode = (str: string) => Buffer.from(str, 'utf8').toString('hex').toUpperCase()
 const chunkString = (str: string, length: number) => str.match(new RegExp('.{1,' + length + '}', 'gs'));
+const genRandHex = size => [...Array(size)].map(() => Math.floor(Math.random() * 16).toString(16)).join('');
 const PAYLOAD_SIZE = 925
-
+const XRP_PER_DROP = 0.000001
+const DROP_PER_XRP = 1000000
 
 
 export class xrpIO {
@@ -63,7 +67,7 @@ export class xrpIO {
     }
   }
 
-  private async sendPayment(data: Memo, to: string, secret: string, sequence?: number): Promise<TxResponse> {
+  private async sendPayment(data: Memo, to: string, secret: string, sequence?: number, amount: string = "1"): Promise<TxResponse> {
     const wallet = Wallet.fromSecret(secret)
     this.dbg("Sending payment", wallet.address, '->', to)
 
@@ -74,7 +78,7 @@ export class xrpIO {
         Account: wallet.address,
         Destination: to,
         Sequence: sequence,
-        Amount: "1",
+        Amount: amount,
         Memos: [{
           Memo: {
             MemoData: hexEncode(data.data || ""),
@@ -96,32 +100,37 @@ export class xrpIO {
     }
   }
 
-  public async writeRaw(data: Memo, to: string, secret: string, sequence?: number): Promise<string> {
+  public async writeRaw(data: Memo, to: string, secret: string, sequence?: number, amount: string = "1"): Promise<string> {
     this.dbg("Writing data", data)
-    const tx = await this.sendPayment(data, to, secret, sequence)
+    const tx = await this.sendPayment(data, to, secret, sequence, amount)
     return tx.result.hash
   }
 
-  private async getTransaction(hash: string, retry=0): Promise<TxResponse> {
+  private async getTransaction(hash: string, retry = 0): Promise<TxResponse> {
     this.dbg("Getting Tx", hash)
-    try{
+    try {
       return await this.api.request({
         command: 'tx',
         transaction: hash,
       })
-    }catch(e){
+    } catch (e) {
       this.dbg(e)
-      if(this.options.readMaxRetry != -1){
-        if(retry >= this.options.readMaxRetry)
-          console.error("Retry limit exceeded for", hash, ". this is an irrecoverable error")
-          throw e
+      if (this.options.readMaxRetry != -1) {
+        if (retry >= this.options.readMaxRetry)
+          console.error("Retry limit exceeded for", hash, ". This is an irrecoverable error")
+        throw e
       }
       await new Promise(res => setTimeout(res, this.options.readRetryTimeout))
-      return await this.getTransaction(hash, retry+1)
+      return await this.getTransaction(hash, retry + 1)
     }
   }
 
   public async readRaw(hash: string): Promise<Memo> {
+
+    if (!NON_ZERO_TX_HASH.test(hash)) {
+      throw ERR_BAD_TX_HASH(hash)
+    }
+
     const tx = await this.getTransaction(hash)
     const memo = tx.result.Memos[0].Memo
     const memoParsed = {
@@ -148,6 +157,10 @@ export class xrpIO {
   }
 
   public async treeRead(hashes: string[]): Promise<string> {
+    const bad_hash = hashes.find(hash => !NON_ZERO_TX_HASH.test(hash))
+    if (bad_hash)
+      throw ERR_BAD_TX_HASH(bad_hash)
+
     const memos = await Promise.all(hashes.map(hash => this.readRaw(hash)))
     const payload: string = await decompressB64(memos.map(memo => memo.data).join(''))
 
@@ -169,6 +182,25 @@ export class xrpIO {
     return Number(accountInfo.result.account_data.Sequence)
   }
 
+  public async estimateFee(data: string, denomination: 'XRP' | 'DROPS' = 'DROPS', cost = 0): Promise<number> {
+    data = await compressB64(data)
+    const chunks = chunkString(data, PAYLOAD_SIZE)
+
+    if (chunks.length === 1) {
+      return (denomination === "DROPS" ? (cost + 1) : this.dropsToXrp(cost + 1))
+    }
+
+    return this.estimateFee(JSON.stringify(chunks.map(_ => genRandHex(64))), denomination, cost + chunks.length)
+  }
+
+  public xrpToDrops(xrp: number): number {
+    return xrp * DROP_PER_XRP
+  }
+
+  public dropsToXrp(drops: number): number {
+    return drops * XRP_PER_DROP
+  }
+
   private dbg(...args: any[]) {
     if (this.options.debug) {
       console.log.apply(console, args)