Move DD code into its own directory (#6)

reference/tests/contrib/sqlalchemy/test_postgres.py

@@ -0,0 +1,64 @@
+import psycopg2
+
+from sqlalchemy.exc import ProgrammingError
+
+import pytest
+
+from .mixins import SQLAlchemyTestMixin
+from ..config import POSTGRES_CONFIG
+from ...base import BaseTracerTestCase
+
+
+class PostgresTestCase(SQLAlchemyTestMixin, BaseTracerTestCase):
+    """TestCase for Postgres Engine"""
+    VENDOR = 'postgres'
+    SQL_DB = 'postgres'
+    SERVICE = 'postgres'
+    ENGINE_ARGS = {'url': 'postgresql://%(user)s:%(password)s@%(host)s:%(port)s/%(dbname)s' % POSTGRES_CONFIG}
+
+    def setUp(self):
+        super(PostgresTestCase, self).setUp()
+
+    def tearDown(self):
+        super(PostgresTestCase, self).tearDown()
+
+    def check_meta(self, span):
+        # check database connection tags
+        self.assertEqual(span.get_tag('out.host'), POSTGRES_CONFIG['host'])
+        self.assertEqual(span.get_metric('out.port'), POSTGRES_CONFIG['port'])
+
+    def test_engine_execute_errors(self):
+        # ensures that SQL errors are reported
+        with pytest.raises(ProgrammingError):
+            with self.connection() as conn:
+                conn.execute('SELECT * FROM a_wrong_table').fetchall()
+
+        traces = self.tracer.writer.pop_traces()
+        # trace composition
+        self.assertEqual(len(traces), 1)
+        self.assertEqual(len(traces[0]), 1)
+        span = traces[0][0]
+        # span fields
+        self.assertEqual(span.name, '{}.query'.format(self.VENDOR))
+        self.assertEqual(span.service, self.SERVICE)
+        self.assertEqual(span.resource, 'SELECT * FROM a_wrong_table')
+        self.assertEqual(span.get_tag('sql.db'), self.SQL_DB)
+        self.assertIsNone(span.get_tag('sql.rows') or span.get_metric('sql.rows'))
+        self.check_meta(span)
+        self.assertEqual(span.span_type, 'sql')
+        self.assertTrue(span.duration > 0)
+        # check the error
+        self.assertEqual(span.error, 1)
+        self.assertTrue('relation "a_wrong_table" does not exist' in span.get_tag('error.msg'))
+        assert 'psycopg2.errors.UndefinedTable' in span.get_tag('error.type')
+        assert 'UndefinedTable: relation "a_wrong_table" does not exist' in span.get_tag('error.stack')
+
+
+class PostgresCreatorTestCase(PostgresTestCase):
+    """TestCase for Postgres Engine that includes the same tests set
+    of `PostgresTestCase`, but it uses a specific `creator` function.
+    """
+    VENDOR = 'postgres'
+    SQL_DB = 'postgres'
+    SERVICE = 'postgres'
+    ENGINE_ARGS = {'url': 'postgresql://', 'creator': lambda: psycopg2.connect(**POSTGRES_CONFIG)}