Add basic BDD infrastructure (#139)

## What is the goal of this PR?

Add BDD infrastructure.

Author: Alex Walker

.grabl/automation.yml

@@ -46,7 +46,7 @@ build:
         bazel run @graknlabs_dependencies//distribution/artifact:create-netrc
         bazel build //...
         bazel run @graknlabs_dependencies//tool/checkstyle:test-coverage
-        bazel test $(bazel query 'kind(checkstyle_test, //...)')
+        bazel test $(bazel query 'kind(checkstyle_test, //...)') --test_output=errors
 #    test-concept:
 #      image: graknlabs-ubuntu-20.04
 #      type: foreground

BUILD

@@ -43,7 +43,7 @@ py_library(
         graknlabs_client_python_requirement("grpcio"),
         graknlabs_client_python_requirement("six"),
     ],
-    visibility =["//visibility:public"]
+    visibility = ["//visibility:public"]
 )
 
 checkstyle_test(

WORKSPACE

@@ -92,8 +92,9 @@ github_deps()
 # Load @graknlabs dependencies #
 ################################
 
-load("//dependencies/graknlabs:repositories.bzl", "graknlabs_common")
+load("//dependencies/graknlabs:repositories.bzl", "graknlabs_common", "graknlabs_behaviour")
 graknlabs_common()
+graknlabs_behaviour()
 
 # Load artifacts
 load("//dependencies/graknlabs:artifacts.bzl", "graknlabs_grakn_core_artifacts")

dependencies/graknlabs/repositories.bzl

@@ -32,3 +32,10 @@ def graknlabs_common():
         remote = "https://github.com/graknlabs/common",
         commit = "cfd261fd5412a0b45cb5494555e4491dd3ce5f64" # sync-marker: do not remove this comment, this is used for sync-dependencies by @graknlabs_common
     )
+
+def graknlabs_behaviour():
+    git_repository(
+        name = "graknlabs_behaviour",
+        remote = "https://github.com/graknlabs/behaviour",
+        commit = "7088622b9f4a3bd99cf4fb278130ad76ff35af6b" # sync-marker: do not remove this comment, this is used for sync-dependencies by @graknlabs_behaviour
+    )

grakn/client.py

@@ -23,9 +23,10 @@
 from grakn.rpc.database_manager import DatabaseManager as _DatabaseManager
 from grakn.rpc.session import Session as _Session, SessionType
 
-# Repackaging these enums allows users to import everything they (most likely) need from "grakn.client"
-from grakn.rpc.transaction import TransactionType  # noqa # pylint: disable=unused-import
+# Repackaging these symbols allows users to import everything they (most likely) need from "grakn.client"
+from grakn.common.exception import GraknClientException  # noqa # pylint: disable=unused-import
 from grakn.concept.type.attribute_type import ValueType  # noqa # pylint: disable=unused-import
+from grakn.rpc.transaction import TransactionType  # noqa # pylint: disable=unused-import
 
 
 class GraknClient(object):
@@ -34,6 +35,7 @@ class GraknClient(object):
     def __init__(self, address=DEFAULT_URI):
         self._channel = grpc.insecure_channel(address)
         self._databases = _DatabaseManager(self._channel)
+        self._is_open = True
 
     def session(self, database: str, session_type: SessionType, options=GraknOptions()):
         return _Session(self, database, session_type, options)
@@ -43,6 +45,10 @@ def databases(self):
 
     def close(self):
         self._channel.close()
+        self._is_open = False
+
+    def is_open(self):
+        return self._is_open
 
     def __enter__(self):
         return self

grakn/query/query_manager.py

@@ -51,28 +51,28 @@ def delete(self, query: str, options=GraknOptions()):
         delete_req = query_proto.Graql.Delete.Req()
         delete_req.query = query
         request.delete_req.CopyFrom(delete_req)
-        self._run_query(request, options)
+        return self._run_query(request, options)
 
     def define(self, query: str, options=GraknOptions()):
         request = query_proto.Query.Req()
         define_req = query_proto.Graql.Define.Req()
         define_req.query = query
         request.define_req.CopyFrom(define_req)
-        self._run_query(request, options)
+        return self._run_query(request, options)
 
     def undefine(self, query: str, options=GraknOptions()):
         request = query_proto.Query.Req()
         undefine_req = query_proto.Graql.Undefine.Req()
         undefine_req.query = query
         request.undefine_req.CopyFrom(undefine_req)
-        self._run_query(request, options)
+        return self._run_query(request, options)
 
     def _run_query(self, query_req: query_proto.Query.Req, options: GraknOptions):
         req = transaction_proto.Transaction.Req()
         query_req.options.CopyFrom(grakn_proto_builder.options(options))
         req.query_req.CopyFrom(query_req)
         # Using stream makes this request asynchronous.
-        self._transaction._stream(req)
+        return self._transaction._stream(req)
 
     def _iterate_query(self, query_req: query_proto.Query.Req, response_reader: Callable[[transaction_proto.Transaction.Res], List], options: GraknOptions):
         req = transaction_proto.Transaction.Req()

grakn/rpc/session.py

@@ -52,10 +52,10 @@ def __init__(self, client, database: str, session_type: SessionType, options=Gra
 
         self._session_id = self._grpc_stub.session_open(open_req).session_id
         self._is_open = True
-        self._scheduler.enter(delay=self._PULSE_FREQUENCY_SECONDS, priority=1, action=self._transmit_pulse, argument=())
+        self._pulse = self._scheduler.enter(delay=self._PULSE_FREQUENCY_SECONDS, priority=1, action=self._transmit_pulse, argument=())
         # TODO: This thread blocks the process from closing. We should try cancelling the scheduled task when the
         #       session closes. If that doesn't work, we need some other way of getting the thread to exit.
-        Thread(target=self._scheduler.run).start()
+        Thread(target=self._scheduler.run, daemon=True).start()
 
     def transaction(self, transaction_type: TransactionType, options=GraknOptions()):
         return Transaction(self._channel, self._session_id, transaction_type, options)
@@ -67,6 +67,8 @@ def is_open(self): return self._is_open
     def close(self):
         if self._is_open:
             self._is_open = False
+            self._scheduler.cancel(self._pulse)
+            self._scheduler.empty()
             req = session_proto.Session.Close.Req()
             req.session_id = self._session_id
             self._grpc_stub.session_close(req)
@@ -80,8 +82,8 @@ def _transmit_pulse(self):
         pulse_req.session_id = self._session_id
         res = self._grpc_stub.session_pulse(pulse_req)
         if res.alive:
-            self._scheduler.enter(delay=self._PULSE_FREQUENCY_SECONDS, priority=1, action=self._transmit_pulse, argument=())
-            Thread(target=self._scheduler.run).start()
+            self._pulse = self._scheduler.enter(delay=self._PULSE_FREQUENCY_SECONDS, priority=1, action=self._transmit_pulse, argument=())
+            Thread(target=self._scheduler.run, daemon=True).start()
 
     def __enter__(self):
         return self

grakn/rpc/stream.py

@@ -31,7 +31,7 @@ class Stream(six.Iterator):
     _CONTINUE = "continue"
     _DONE = "done"
 
-    def __init__(self, transaction, request_id: str, transform_response: Callable[[transaction_proto.Transaction.Res], List] = None):
+    def __init__(self, transaction, request_id: str, transform_response: Callable[[transaction_proto.Transaction.Res], List] = lambda res: None):
         self._transaction = transaction
         self._request_id = request_id
         self._transform_response = transform_response

requirements.txt

@@ -17,8 +17,21 @@
 # under the License.
 #
 
-# --extra-index-url https://repo.grakn.ai/repository/pypi-snapshot/simple
+
+## Configuration options
+
+# --extra-index-url https://repo.grakn.ai/repository/pypi-snapshot/simple  # Allow importing of snapshots
+
+
+## Dependencies
+
 graknprotocol==2.0.0a4
 grpcio==1.33.2
 protobuf==3.6.1
 six>=1.11.0
+
+
+# Dev dependencies (not required to use the grakn-client package, but necessary for its development)
+
+behave==1.2.6
+PyHamcrest==2.0.2

test/BUILD renamed to tests/BUILD

@@ -17,6 +17,7 @@
 # under the License.
 #
 
+# Note: Do NOT rename this folder to 'test' as it conflicts with a built-in Python package!
 load("@graknlabs_common//test/server:rules.bzl", "native_grakn_artifact")
 load("@graknlabs_dependencies//tool/checkstyle:rules.bzl", "checkstyle_test")
 load("@rules_python//python:defs.bzl", "py_library", "py_test")
@@ -26,7 +27,7 @@ native_grakn_artifact(
     mac_artifact = "@graknlabs_grakn_core_artifact_mac//file",
     linux_artifact = "@graknlabs_grakn_core_artifact_linux//file",
     windows_artifact = "@graknlabs_grakn_core_artifact_windows//file",
-    visibility = ["//test:__subpackages__"],
+    visibility = ["//tests:__subpackages__"],
 )
 
 py_test(