sms verification: move helper functions

- checkIfTxFailed & waitForBlockConfirmations are both general-purpose
- checkIfVerified, checkIfRequested & postToServer are sms verification-specific

js/src/util/check-if-tx-failed.js

@@ -0,0 +1,28 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+const checkIfTxFailed = (api, tx, gasSent) => {
+  return api.pollMethod('eth_getTransactionReceipt', tx)
+  .then((receipt) => {
+    // TODO: Right now, there's no way to tell wether the EVM code crashed.
+    // Because you usually send a bit more gas than estimated (to make sure
+    // it gets mined quickly), we transaction probably failed if all the gas
+    // has been used up.
+    return receipt.gasUsed.eq(gasSent);
+  });
+};
+
+export default checkIfTxFailed;

js/src/util/wait-for-block-confirmations.js

@@ -0,0 +1,44 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+const isValidReceipt = (receipt) => {
+  return receipt && receipt.blockNumber && receipt.blockNumber.gt(0);
+};
+
+const waitForConfirmations = (api, tx, confirmations) => {
+  return new Promise((resolve, reject) => {
+    api.pollMethod('eth_getTransactionReceipt', tx, isValidReceipt)
+    .then((receipt) => {
+      let subscription;
+      api.subscribe('eth_blockNumber', (err, block) => {
+        if (err) {
+          reject(err);
+        } else if (block.minus(confirmations - 1).gte(receipt.blockNumber)) {
+          if (subscription) {
+            api.unsubscribe(subscription);
+          }
+          resolve();
+        }
+      })
+      .then((_subscription) => {
+        subscription = _subscription;
+      })
+      .catch(reject);
+    });
+  });
+};
+
+export default waitForConfirmations;