FIX: limit number of userinvoices feetched per polling request

LightningCustodianWallet.test.js

@@ -263,6 +263,14 @@ describe('LightningCustodianWallet', () => {
     await lOld.fetchTransactions();
     assert.equal(txLen, lOld.transactions_raw.length, 'tx count should not be changed');
     assert.equal(invLen, (await lNew.getUserInvoices()).length, 'invoices count should not be changed');
+
+    // testing how limiting works:
+    assert.equal(lNew.user_invoices_raw.length, 1);
+    await lNew.addInvoice(666, 'test memo 2');
+    invoices = await lNew.getUserInvoices(1);
+    assert.equal(invoices.length, 2);
+    assert.equal(invoices[0].amt, 1);
+    assert.equal(invoices[1].amt, 666);
   });
 
   it('can pay free amount (tip) invoice', async function() {

class/lightning-custodian-wallet.js

@@ -17,6 +17,7 @@ export class LightningCustodianWallet extends LegacyWallet {
     this._access_token_created_ts = 0;
     this.refill_addressess = [];
     this.pending_transactions_raw = [];
+    this.user_invoices_raw = [];
     this.info_raw = false;
     this.preferredBalanceUnit = BitcoinUnit.SATS;
   }
@@ -128,8 +129,10 @@ export class LightningCustodianWallet extends LegacyWallet {
    *
    * @return {Promise.<Array>}
    */
-  async getUserInvoices() {
-    let response = await this._api.get('/getuserinvoices', {
+  async getUserInvoices(limit = false) {
+    let limitString = '';
+    if (limit) limitString = '?limit=' + parseInt(limit);
+    let response = await this._api.get('/getuserinvoices' + limitString, {
       headers: {
         'Access-Control-Allow-Origin': '*',
         'Content-Type': 'application/json',
@@ -144,9 +147,31 @@ export class LightningCustodianWallet extends LegacyWallet {
     if (json && json.error) {
       throw new Error('API error: ' + json.message + ' (code ' + json.code + ')');
     }
-    this.user_invoices_raw = json;
 
-    return json;
+    if (limit) {
+      // need to merge existing invoices with the ones that arrived
+      // but the ones received later should overwrite older ones
+
+      for (let oldInvoice of this.user_invoices_raw) {
+        // iterate all OLD invoices
+        let found = false;
+        for (let newInvoice of json) {
+          // iterate all NEW invoices
+          if (newInvoice.payment_request === oldInvoice.payment_request) found = true;
+        }
+
+        if (!found) {
+          // if old invoice is not found in NEW array, we simply add it:
+          json.push(oldInvoice);
+        }
+      }
+    }
+
+    this.user_invoices_raw = json.sort(function(a, b) {
+      return a.timestamp - b.timestamp;
+    });
+
+    return this.user_invoices_raw;
   }
 
   /**

screen/lnd/lndViewInvoice.js

@@ -38,8 +38,11 @@ export default class LNDViewInvoice extends Component {
     this.fetchInvoiceInterval = setInterval(async () => {
       if (this.state.isFetchingInvoices) {
         try {
-          const userInvoices = JSON.stringify(await this.state.fromWallet.getUserInvoices());
-          const updatedUserInvoice = JSON.parse(userInvoices).filter(invoice =>
+          const userInvoices = await this.state.fromWallet.getUserInvoices(20);
+          // fetching only last 20 invoices
+          // for invoice that was created just now - that should be enough (it is basically the last one, so limit=1 would be sufficient)
+          // but that might not work as intended IF user creates 21 invoices, and then tries to check the status of invoice #0, it just wont be updated
+          const updatedUserInvoice = userInvoices.filter(invoice =>
             typeof this.state.invoice === 'object'
               ? invoice.payment_request === this.state.invoice.payment_request
               : invoice.payment_request === this.state.invoice,