UPDATE tutorial with recoverPublicKey

test/tutorials/encrypted-message.test.js

@@ -21,8 +21,7 @@ describe('encrypted-message.md', () => {
 
         const payload = {
             message: secretMessage,
-            signature,
-            sender: alice.publicKey
+            signature
         };
         const encrypted = await EthCrypto.encryptWithPublicKey(
             bob.publicKey,
@@ -37,28 +36,16 @@ describe('encrypted-message.md', () => {
             encrypted
         );
         const decryptedPayload = JSON.parse(decrypted);
-        const senderAddress = EthCrypto.addressByPublicKey(decryptedPayload.sender);
-        // console.log('decryptedPayload:');
-        // console.dir(decryptedPayload);
 
         // check signature
-        const signer = EthCrypto.recover(
+        const senderAddress = EthCrypto.recover(
             decryptedPayload.signature,
             EthCrypto.hash.keccak256(payload.message)
         );
-        if (signer !== senderAddress)
-            throw new Error('signature not valid');
 
-        /*        console.log(
-                    'Got message from ' +
-                    senderAddress +
-                    ': "' +
-                    decryptedPayload.message + '"'
-                );
-        */
+        assert.equal(senderAddress, alice.address);
         assert.equal(decryptedPayload.message, secretMessage);
 
-
         // answer
         const answerMessage = 'Roger dad';
         const answerSignature = EthCrypto.sign(
@@ -67,11 +54,18 @@ describe('encrypted-message.md', () => {
         );
         const answerPayload = {
             message: answerMessage,
-            signature: answerSignature,
-            sender: bob.publicKey
+            signature: answerSignature
         };
+
+        const alicePublicKey = EthCrypto.recoverPublicKey(
+            decryptedPayload.signature,
+            EthCrypto.hash.keccak256(payload.message)
+        );
+
+        assert.equal(alicePublicKey, alice.publicKey);
+
         const encryptedAnswer = await EthCrypto.encryptWithPublicKey(
-            decryptedPayload.sender,
+            alicePublicKey,
             JSON.stringify(answerPayload)
         );
         assert.ok(encryptedAnswer);

tutorials/encrypted-message.md

@@ -30,8 +30,7 @@ const signature = EthCrypto.sign(
 );
 const payload = {
     message: secretMessage,
-    signature,
-    sender: alice.publicKey
+    signature
 };
 const encrypted = await EthCrypto.encryptWithPublicKey(
     bob.publicKey, // by encryping with bobs publicKey, only bob can decrypt the payload with his privateKey
@@ -57,15 +56,12 @@ const decrypted = await EthCrypto.decryptWithPrivateKey(
     encrypted
 );
 const decryptedPayload = JSON.parse(decrypted);
-const senderAddress = EthCrypto.addressByPublicKey(decryptedPayload.sender);
 
 // check signature
-const signer = EthCrypto.recover(
+const senderAddress = EthCrypto.recover(
     decryptedPayload.signature,
     EthCrypto.hash.keccak256(payload.message)
 );
-if (signer !== senderAddress)
-    throw new Error('signature not valid');
 
 console.log(
     'Got message from ' +
@@ -79,20 +75,26 @@ console.log(
 ## Creating an answer
 
 Now that `Bob` got the message, he can also answer back to alice.
+To to this he has to recover the publicKey of alice with `recoverPublicKey()`.
 
 ```javascript
-const answerMessage = 'Roger dad';
+const answerMessage = 'And I am Bob Kelso';
 const answerSignature = EthCrypto.sign(
     bob.privateKey,
     EthCrypto.hash.keccak256(answerMessage)
 );
 const answerPayload = {
     message: answerMessage,
-    signature: answerSignature,
-    sender: bob.publicKey
+    signature: answerSignature
 };
+
+const alicePublicKey = EthCrypto.recoverPublicKey(
+    decryptedPayload.signature,
+    EthCrypto.hash.keccak256(payload.message)
+);
+
 const encryptedAnswer = await EthCrypto.encryptWithPublicKey(
-    decryptedPayload.sender,
+    alicePublicKey,
     JSON.stringify(answerPayload)
 );
 // now we send the encryptedAnswer to alice over the internet.. *bieb, bieb, blob*