feat(ibis): add Cloud Spanner backend (#186)

* ibis_cloud_spanner folder added

* Added tests folder for ibis_cloud_spanner connector

* increase large compile time for cloud build

* rename project param to project_id

This is consistent with the BigQuery Ibis connector

Co-authored-by: Tim Swast <swast@google.com>

cloudbuild.yaml

@@ -41,3 +41,10 @@ steps:
   - 'NOX_SESSION=integration_bigquery'
   - 'PROJECT_ID=pso-kokoro-resources'
   waitFor: ['-']
+- id: integration_spanner
+  name: 'gcr.io/pso-kokoro-resources/python-multi'
+  args: ['bash', './ci/build.sh']
+  env:
+  - 'NOX_SESSION=integration_spanner'
+  - 'PROJECT_ID=pso-kokoro-resources'
+  waitFor: ['-']

noxfile.py

@@ -137,3 +137,19 @@ def integration_bigquery(session):
             raise Exception("Expected Env Var: %s" % env_var)
 
     session.run("pytest", test_path, *session.posargs)
+
+
+@nox.session(python=PYTHON_VERSIONS, venv_backend="venv")
+def integration_spanner(session):
+    """Run Spanner integration tests.
+    Ensure Spanner validation is running as expected.
+    """
+    _setup_session_requirements(session, extra_packages=[])
+
+    expected_env_vars = ["PROJECT_ID"]
+    for env_var in expected_env_vars:
+        if not os.environ.get(env_var, ""):
+            raise Exception("Expected Env Var: %s" % env_var)
+
+    # TODO: Add tests for DVT data sources. See integration_bigquery.
+    session.run("pytest", "third_party/ibis/ibis_cloud_spanner/tests", *session.posargs)

requirements.txt

@@ -16,5 +16,6 @@ pyarrow==3.0.0
 pydata-google-auth==1.1.0
 google-cloud-bigquery==2.7.0
 google-cloud-bigquery-storage==2.2.1
+google-cloud-spanner==3.1.0
 setuptools>=34.0.0
 jellyfish==0.8.2

third_party/ibis/ibis_cloud_spanner/__init__.py

@@ -0,0 +1,2 @@
+
+

third_party/ibis/ibis_cloud_spanner/api.py

@@ -0,0 +1,80 @@
+# Copyright 2021 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+"""CloudSpanner public API."""
+
+
+from third_party.ibis.ibis_cloud_spanner.client import CloudSpannerClient
+from third_party.ibis.ibis_cloud_spanner.compiler import dialect
+
+import google.cloud.spanner  # noqa: F401, fail early if spanner is missing
+import ibis.common.exceptions as com
+
+__all__ = ("compile", "connect", "verify")
+
+
+def compile(expr, params=None):
+    """Compile an expression for Cloud Spanner.
+
+    Returns
+    -------
+    compiled : str
+
+    See Also
+    --------
+    ibis.expr.types.Expr.compile
+
+    """
+    from third_party.ibis.ibis_cloud_spanner.compiler import to_sql
+
+    return to_sql(expr, dialect.make_context(params=params))
+
+
+def verify(expr, params=None):
+    """Check if an expression can be compiled using Cloud Spanner."""
+    try:
+        compile(expr, params=params)
+        return True
+    except com.TranslationError:
+        return False
+
+
+def connect(
+    instance_id,
+    database_id,
+    project_id=None,
+) -> CloudSpannerClient:
+    """Create a CloudSpannerClient for use with Ibis.
+
+    Parameters
+    ----------
+    instance_id : str
+        A Cloud Spanner Instance id.
+    database_id : str
+        A database id inside of the Cloud Spanner Instance
+    project_id  : str (Optional)
+        The ID of the project which owns the instances, tables and data.
+
+    Returns
+    -------
+    CloudSpannerClient
+
+    """
+
+    return CloudSpannerClient(
+        instance_id=instance_id,
+        database_id=database_id,
+        project_id=project_id,
+    )