4.0 handshake testing (#357)

* Added unit test for exceptions

* Fixed Bolt.open error message

* added stubtests for handshake negotiation of different bolt protocol versions

* integration tests are skipped if the bolt protocol version is not supported by the driver.

* Removed unused import

* Removed assert on repr of exception

* Enabled python 3.8 in test

Author: martin-neotech

neo4j/io/__init__.py

@@ -70,6 +70,7 @@
     BoltRoutingError,
     BoltSecurityError,
     BoltProtocolError,
+    BoltHandshakeError,
 )
 from neo4j.exceptions import (
     ServiceUnavailable,
@@ -168,7 +169,7 @@ def open(cls, address, *, auth=None, timeout=None, **config):
         :return:
         """
         config = PoolConfig.consume(config)
-        s, config.protocol_version = connect(address, timeout=timeout, config=config)
+        s, config.protocol_version, handshake, data = connect(address, timeout=timeout, config=config)
 
         if config.protocol_version == (3, 0):
             from neo4j.io._bolt3 import Bolt3
@@ -180,7 +181,9 @@ def open(cls, address, *, auth=None, timeout=None, **config):
             log.debug("[#%04X]  S: <CLOSE>", s.getpeername()[1])
             s.shutdown(SHUT_RDWR)
             s.close()
-            raise BoltProtocolError("Driver does not support Bolt protocol version: 0x%06X%02X", config.protocol_version[0], config.protocol_version[1])
+
+            supported_versions = Bolt.protocol_handlers().keys()
+            raise BoltHandshakeError("The Neo4J server does not support communication with this driver. This driver have support for Bolt Protocols {}".format(supported_versions), address=address, request_data=handshake, response_data=data)
 
         connection.hello()
         return connection
@@ -849,7 +852,7 @@ def _handshake(s, resolved_address):
                                  "(looks like HTTP)".format(resolved_address))
     agreed_version = data[-1], data[-2]
     log.debug("[#%04X]  S: <HANDSHAKE> 0x%06X%02X", local_port, agreed_version[1], agreed_version[0])
-    return s, agreed_version
+    return s, agreed_version, handshake, data
 
 
 def connect(address, *, timeout=None, config):

tests/integration/aio/conftest.py

@@ -18,21 +18,27 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-
-from pytest import fixture
+import pytest
 
 from neo4j.aio import Bolt, BoltPool
+from neo4j._exceptions import BoltHandshakeError
 
 
-@fixture
+@pytest.fixture
 async def bolt(address, auth):
-    bolt = await Bolt.open(address, auth=auth)
-    yield bolt
-    await bolt.close()
+    try:
+        bolt = await Bolt.open(address, auth=auth)
+        yield bolt
+        await bolt.close()
+    except BoltHandshakeError as error:
+        pytest.skip(error.args[0])
 
 
-@fixture
+@pytest.fixture
 async def bolt_pool(address, auth):
-    pool = await BoltPool.open(address, auth=auth)
-    yield pool
-    await pool.close()
+    try:
+        pool = await BoltPool.open(address, auth=auth)
+        yield pool
+        await pool.close()
+    except BoltHandshakeError as error:
+        pytest.skip(error.args[0])