Add error logs for connecting to HTTP server

The driver already throws an aproprietade erro when the server returns HTTP.
Add this information to the log helps with future debugging process.

Author: bigmontz

packages/bolt-connection/src/bolt/handshake.js

@@ -54,14 +54,16 @@ function createHandshakeMessage (versions) {
   return handshakeBuffer
 }
 
-function parseNegotiatedResponse (buffer) {
+function parseNegotiatedResponse (buffer, log) {
   const h = [
     buffer.readUInt8(),
     buffer.readUInt8(),
     buffer.readUInt8(),
     buffer.readUInt8()
   ]
   if (h[0] === 0x48 && h[1] === 0x54 && h[2] === 0x54 && h[3] === 0x50) {
+    log.error('Handshake failed since server responded with HTTP.')
+
     throw newError(
       'Server responded HTTP. Make sure you are not trying to connect to the http endpoint ' +
         '(HTTP defaults to port 7474 whereas BOLT defaults to port 7687)'
@@ -97,9 +99,10 @@ function newHandshakeBuffer () {
  * Shake hands using the channel and return the protocol version
  *
  * @param {Channel} channel the channel use to shake hands
+ * @param {Logger} log the log object
  * @returns {Promise<HandshakeResult>} Promise of protocol version and consumeRemainingBuffer
  */
-export default function handshake (channel) {
+export default function handshake (channel, log) {
   return new Promise((resolve, reject) => {
     const handshakeErrorHandler = error => {
       reject(error)
@@ -113,7 +116,7 @@ export default function handshake (channel) {
     channel.onmessage = buffer => {
       try {
         // read the response buffer and initialize the protocol
-        const protocolVersion = parseNegotiatedResponse(buffer)
+        const protocolVersion = parseNegotiatedResponse(buffer, log)
 
         resolve({
           protocolVersion,

packages/bolt-connection/src/connection/connection-channel.js

@@ -53,7 +53,7 @@ export function createChannelConnection (
 
   const channel = createChannel(channelConfig)
 
-  return Bolt.handshake(channel)
+  return Bolt.handshake(channel, log)
     .then(({ protocolVersion: version, consumeRemainingBuffer }) => {
       const chunker = new Chunker(channel)
       const dechunker = new Dechunker()

packages/bolt-connection/test/bolt/index.test.js

@@ -74,7 +74,7 @@ describe('#unit Bolt', () => {
       channel.onmessage(packedHandshakeMessage(expectedProtocolVersion))
     })
 
-    it('should handle a successful handshake with reaining buffer', done => {
+    it('should handle a successful handshake with remaining buffer', done => {
       const { channel, handshakePromise } = subject()
       const expectedProtocolVersion = 4.3
       const expectedExtraBuffer = createExtraBuffer()
@@ -114,6 +114,29 @@ describe('#unit Bolt', () => {
 
       channel.onmessage(packedHandshakeMessage(httpMagicNumber))
     })
+
+    it('should log error if the server responds with http server', async () => {
+      const { channel, handshakePromise, log } = subject()
+      const httpMagicNumber = 1213486160
+      const logErrorSpy = jest.spyOn(log, 'error')
+
+      channel.onmessage(packedHandshakeMessage(httpMagicNumber))
+
+      await expect(handshakePromise).rejects.toThrow()
+      expect(logErrorSpy).toHaveBeenCalledWith('Handshake failed since server responded with HTTP.')
+    })
+
+    it('should not log error if the server responds valid protocol version', async () => {
+      const { channel, handshakePromise, log } = subject()
+      const expectedProtocolVersion = 4.3
+      const logErrorSpy = jest.spyOn(log, 'error')
+
+      channel.onmessage(packedHandshakeMessage(expectedProtocolVersion))
+
+      await expect(handshakePromise).resolves.not.toThrow()
+      expect(logErrorSpy).not.toBeCalled()
+    })
+
     it('should handle a failed handshake', done => {
       const { channel, handshakePromise } = subject()
       const expectedError = new Error('Something got wrong')
@@ -143,9 +166,11 @@ describe('#unit Bolt', () => {
     })
 
     function subject ({ channel = new DummyChannel() } = {}) {
+      const log = new Logger('debug', () => {})
       return {
+        log,
         channel,
-        handshakePromise: Bolt.handshake(channel)
+        handshakePromise: Bolt.handshake(channel, log)
       }
     }
 

packages/neo4j-driver-deno/lib/bolt-connection/bolt/handshake.js

@@ -54,14 +54,16 @@ function createHandshakeMessage (versions) {
   return handshakeBuffer
 }
 
-function parseNegotiatedResponse (buffer) {
+function parseNegotiatedResponse (buffer, log) {
   const h = [
     buffer.readUInt8(),
     buffer.readUInt8(),
     buffer.readUInt8(),
     buffer.readUInt8()
   ]
   if (h[0] === 0x48 && h[1] === 0x54 && h[2] === 0x54 && h[3] === 0x50) {
+    log.error('Handshake failed since server responded with HTTP.')
+
     throw newError(
       'Server responded HTTP. Make sure you are not trying to connect to the http endpoint ' +
         '(HTTP defaults to port 7474 whereas BOLT defaults to port 7687)'
@@ -97,9 +99,10 @@ function newHandshakeBuffer () {
  * Shake hands using the channel and return the protocol version
  *
  * @param {Channel} channel the channel use to shake hands
+ * @param {Logger} log the log object
  * @returns {Promise<HandshakeResult>} Promise of protocol version and consumeRemainingBuffer
  */
-export default function handshake (channel) {
+export default function handshake (channel, log) {
   return new Promise((resolve, reject) => {
     const handshakeErrorHandler = error => {
       reject(error)
@@ -113,7 +116,7 @@ export default function handshake (channel) {
     channel.onmessage = buffer => {
       try {
         // read the response buffer and initialize the protocol
-        const protocolVersion = parseNegotiatedResponse(buffer)
+        const protocolVersion = parseNegotiatedResponse(buffer, log)
 
         resolve({
           protocolVersion,

packages/neo4j-driver-deno/lib/bolt-connection/connection/connection-channel.js

@@ -53,7 +53,7 @@ export function createChannelConnection (
 
   const channel = createChannel(channelConfig)
 
-  return Bolt.handshake(channel)
+  return Bolt.handshake(channel, log)
     .then(({ protocolVersion: version, consumeRemainingBuffer }) => {
       const chunker = new Chunker(channel)
       const dechunker = new Dechunker()

packages/neo4j-driver/test/internal/connection-channel.test.js

@@ -133,7 +133,7 @@ describe('#integration ChannelConnection', () => {
   it('should provide error message when connecting to http-port', async done => {
     await createConnection(`bolt://${sharedNeo4j.hostname}:7474`, {
       encrypted: false
-    })
+    }, null, new Logger('error', () => {}))
       .then(done.fail.bind(done))
       .catch(error => {
         expect(error).toBeDefined()