Op get pos economis (#275)

* cfx_getPoSEconomics support optional epoch parameter

* update d.ts

package.json

@@ -1,7 +1,7 @@
 {
   "name": "js-conflux-sdk",
   "description": "JavaScript Conflux Software Development Kit",
-  "version": "2.4.7",
+  "version": "2.4.9",
   "license": "LGPL-3.0",
   "author": "[email protected]",
   "repository": "https://github.com/Conflux-Chain/js-conflux-sdk.git",

src/Conflux.js

@@ -1267,14 +1267,15 @@ class Conflux {
 
   /**
    * Return PoS summary info
+   * @param {number|string} epochNumber - epoch number
    * @returns {Promise<import('./rpc/types/formatter').PoSEconomics>} PoS summary info
    * - distributablePosInterest `number`: Currently total distributable PoS interest (Drip)
    * - lastDistributeBlock `number`: Last distribute block number
    * - totalPosStakingTokens `number`: Total token amount (Drip) staked in PoS
    *
    */
-  async getPoSEconomics() {
-    return this.cfx.getPoSEconomics();
+  async getPoSEconomics(epochNumber) {
+    return this.cfx.getPoSEconomics(epochNumber);
   }
 
   // ----------------------------- subscription -------------------------------

src/rpc/cfx.js

@@ -318,6 +318,9 @@ class CFX extends RPCMethodFactory {
       },
       {
         method: 'cfx_getPoSEconomics',
+        requestFormatters: [
+          format.epochNumberOrUndefined,
+        ],
         responseFormatter: cfxFormat.posEconomics,
       },
       {