Merge pull request #4 from Dhaiwat10/restrictions

Add withdrawal restrictions (#1)

.env.example

@@ -1,4 +1,11 @@
 ROPSTEN_PRIVATE_KEY=
 INFURA_API_KEY=
 NEXT_PUBLIC_CONTRACT_ADDRESS=
-CALLER_SECRET=
+CALLER_SECRET=
+FIREBASE_API_KEY=
+FIREBASE_AUTH_DOMAIN=
+FIREBASE_PROJECT_ID=
+FIREBASE_STORAGE_BUCKET=
+FIREBASE_MESSAGING_ID=
+FIREBASE_APP_ID=
+FIREBASE_MEASUREMENT_ID=

ADDRESS

@@ -0,0 +1 @@
+0xEccA7BF722455A94b9e759247aB86E2e1559c871

package.json

@@ -47,6 +47,7 @@
   },
   "dependencies": {
     "axios": "^0.21.1",
+    "firebase": "^8.4.1",
     "next": "^10.1.3",
     "react": "^17.0.2",
     "react-dom": "^17.0.2",

src/lib/db.ts

@@ -0,0 +1,41 @@
+import { firebase } from './firebase';
+
+export const validateRequest = async (address: string): Promise<boolean> => {
+  try {
+    const ref = firebase.database().ref('addresses/');
+    const currentTime = Date.now();
+
+    const snapshot = await ref.child(address).get();
+
+    if (snapshot.exists()) {
+      // Previous record exists
+
+      // Validate request
+      if (currentTime - snapshot.val() < 8.64e7) {
+        // Cooldown not over yet
+        return false;
+      } else {
+        // Cooldown over
+        return true;
+      }
+    } else {
+      // Allow withdrawal
+      return true;
+    }
+  } catch (error) {
+    console.log(error);
+    return false;
+  }
+};
+
+export const createRecord = async (address: string): Promise<boolean> => {
+  try {
+    const currentTime = Date.now();
+    const ref = firebase.database().ref('addresses/' + address);
+    await ref.set(currentTime);
+    return true;
+  } catch (error) {
+    console.log(error);
+    return false;
+  }
+};

src/lib/firebase.ts

@@ -0,0 +1,19 @@
+import firebase from 'firebase/app';
+import 'firebase/firebase-database';
+
+const firebaseConfig = {
+  apiKey: process.env.FIREBASE_API_KEY,
+  authDomain: process.env.FIREBASE_AUTH_DOMAIN,
+  projectId: process.env.FIREBASE_PROJECT_ID,
+  storageBucket: process.env.FIREBASE_STORAGE_BUCKET,
+  messagingSenderId: process.env.FIREBASE_MESSAGING_ID,
+  appId: process.env.FIREBASE_APP_ID,
+  measurementId: process.env.FIREBASE_MEASUREMENT_ID,
+};
+
+if (typeof window !== 'undefined' && !firebase.apps.length) {
+  firebase.initializeApp(firebaseConfig);
+  firebase.database();
+}
+
+export { firebase };

src/pages/index.tsx

@@ -2,6 +2,7 @@ import { FormEvent, useEffect, useState } from 'react';
 import { Button, Container, Form, Input, Message } from 'semantic-ui-react';
 import { verifyEthAddress } from '../util';
 import axios from 'axios';
+import { createRecord, validateRequest } from '../lib/db';
 
 function Home(): React.ReactNode {
   const [value, setValue] = useState('');
@@ -24,9 +25,26 @@ function Home(): React.ReactNode {
   };
 
   const requestFunds = async () => {
+    setSuccess(false);
+    setError('');
     setLoading(true);
     try {
+      const validity = await validateRequest(value);
+      if (!validity) {
+        setLoading(false);
+        setError(
+          'You can make only 1 request in a day. Please try again later.'
+        );
+        return;
+      }
       await axios.post('/api', { address: value });
+      const recordCreated = await createRecord(value);
+
+      if (!recordCreated) {
+        // TODO: Creating the record failed, probably report this
+        console.log('Couldnt create the record');
+      }
+
       setSuccess(true);
     } catch (e) {
       console.log(e);
@@ -64,8 +82,8 @@ function Home(): React.ReactNode {
   }, []);
 
   return (
-    <Container>
-      <Form success={success} error={!!error} onSubmit={onSubmit}>
+    <Container style={{ height: '100vh' }}>
+      <Form style={{ marginTop: 100 }} success={success} error={!!error} onSubmit={onSubmit}>
         <h1>Ropsten Faucet</h1>
         <Form.Field error={touched && !isValid}>
           <label>Your Ropsten wallet address</label>
@@ -83,13 +101,14 @@ function Home(): React.ReactNode {
             content="0.1 ether will soon be transferred to your wallet."
           />
         )}
-        <Button loading={loading} primary>
+        <Button style={{ marginBottom: 10 }} loading={loading} primary>
           Request Ether
         </Button>
       </Form>
       {contractBalance ? (
         <span>
-          Contract balance: {parseInt(contractBalance || '') / Math.pow(10, 18)}{' '}
+          Contract balance:{' '}
+          {(parseInt(contractBalance || '') / Math.pow(10, 18), 2).toFixed(2)}{' '}
           ether
         </span>
       ) : null}