Types cleanup + more API methods onto new request method (#857)

* major types cleanup, more formatted api methods onto new request method

- getPaymentChannel() now uses this.request()
- getSettings() now uses this.request()
- getLedger() now uses this.request()
- transaction types cleaned up a bit, but still some work left to do

src/ledger/ledger.ts

@@ -1,28 +1,29 @@
 import {validate} from '../common'
-import parseLedger from './parse/ledger'
-import {GetLedger} from './types'
+import {FormattedLedger, parseLedger} from './parse/ledger'
+import {RippleAPI} from '../api'
 
-export type LedgerOptions = {
+export type GetLedgerOptions = {
   ledgerVersion?: number,
   includeAllData?: boolean,
   includeTransactions?: boolean,
   includeState?: boolean
 }
 
-
-function getLedger(options: LedgerOptions = {}): Promise<GetLedger> {
+async function getLedger(
+  this: RippleAPI, options: GetLedgerOptions = {}
+): Promise<FormattedLedger> {
+  // 1. Validate
   validate.getLedger({options})
-
-  const request = {
-    command: 'ledger',
+  // 2. Make Request
+  const response = await this._request('ledger', {
     ledger_index: options.ledgerVersion || 'validated',
     expand: options.includeAllData,
     transactions: options.includeTransactions,
     accounts: options.includeState
-  }
-
-  return this.connection.request(request).then(response =>
-    parseLedger(response.ledger))
+  })
+  // 3. Return Formatted Response
+  return parseLedger(response.ledger)
 }
 
+
 export default getLedger