From 7e99d768af2e60eeb4cba80509196fcd9e38340d Mon Sep 17 00:00:00 2001
From: Ville Brofeldt <33317356+villebro@users.noreply.github.com>
Date: Tue, 19 Jan 2021 14:32:33 +0200
Subject: [PATCH] feat(bigquery): implement custom minute time grains (#12581)

* feat(bigquery): implement custom minute time grains

* address review comment
---
 superset/db_engine_specs/base.py        |  4 ++++
 superset/db_engine_specs/bigquery.py    | 12 ++++++++++++
 tests/db_engine_specs/bigquery_tests.py | 22 ++++++++++++++++++++++
 3 files changed, 38 insertions(+)

diff --git a/superset/db_engine_specs/base.py b/superset/db_engine_specs/base.py
index c1240c5c7..2a29c9517 100644
--- a/superset/db_engine_specs/base.py
+++ b/superset/db_engine_specs/base.py
@@ -245,6 +245,10 @@ class BaseEngineSpec:  # pylint: disable=too-many-public-methods
                 date_trunc_function = cls._date_trunc_functions.get(type_)
                 if date_trunc_function:
                     time_expr = time_expr.replace("{func}", date_trunc_function)
+            if type_ and "{type}" in time_expr:
+                date_trunc_function = cls._date_trunc_functions.get(type_)
+                if date_trunc_function:
+                    time_expr = time_expr.replace("{type}", type_)
         else:
             time_expr = "{col}"
 
diff --git a/superset/db_engine_specs/bigquery.py b/superset/db_engine_specs/bigquery.py
index 574a439cb..621525060 100644
--- a/superset/db_engine_specs/bigquery.py
+++ b/superset/db_engine_specs/bigquery.py
@@ -66,6 +66,18 @@ class BigQueryEngineSpec(BaseEngineSpec):
         None: "{col}",
         "PT1S": "{func}({col}, SECOND)",
         "PT1M": "{func}({col}, MINUTE)",
+        "PT5M": "CAST(TIMESTAMP_SECONDS("
+        "5*60 * DIV(UNIX_SECONDS(CAST({col} AS TIMESTAMP)), 5*60)"
+        ") AS {type})",
+        "PT10M": "CAST(TIMESTAMP_SECONDS("
+        "10*60 * DIV(UNIX_SECONDS(CAST({col} AS TIMESTAMP)), 10*60)"
+        ") AS {type})",
+        "PT15M": "CAST(TIMESTAMP_SECONDS("
+        "15*60 * DIV(UNIX_SECONDS(CAST({col} AS TIMESTAMP)), 15*60)"
+        ") AS {type})",
+        "PT0.5H": "CAST(TIMESTAMP_SECONDS("
+        "30*60 * DIV(UNIX_SECONDS(CAST({col} AS TIMESTAMP)), 30*60)"
+        ") AS {type})",
         "PT1H": "{func}({col}, HOUR)",
         "P1D": "{func}({col}, DAY)",
         "P1W": "{func}({col}, WEEK)",
diff --git a/tests/db_engine_specs/bigquery_tests.py b/tests/db_engine_specs/bigquery_tests.py
index 8e9ae7d0a..37e95e95e 100644
--- a/tests/db_engine_specs/bigquery_tests.py
+++ b/tests/db_engine_specs/bigquery_tests.py
@@ -74,6 +74,28 @@ class TestBigQueryDbEngineSpec(TestDbEngineSpec):
             )
             self.assertEqual(str(actual), expected)
 
+    def test_custom_minute_timegrain_expressions(self):
+        """
+        DB Eng Specs (bigquery): Test time grain expressions
+        """
+        col = column("temporal")
+        test_cases = {
+            "DATE": "CAST(TIMESTAMP_SECONDS("
+            "5*60 * DIV(UNIX_SECONDS(CAST(temporal AS TIMESTAMP)), 5*60)"
+            ") AS DATE)",
+            "DATETIME": "CAST(TIMESTAMP_SECONDS("
+            "5*60 * DIV(UNIX_SECONDS(CAST(temporal AS TIMESTAMP)), 5*60)"
+            ") AS DATETIME)",
+            "TIMESTAMP": "CAST(TIMESTAMP_SECONDS("
+            "5*60 * DIV(UNIX_SECONDS(CAST(temporal AS TIMESTAMP)), 5*60)"
+            ") AS TIMESTAMP)",
+        }
+        for type_, expected in test_cases.items():
+            actual = BigQueryEngineSpec.get_timestamp_expr(
+                col=col, pdf=None, time_grain="PT5M", type_=type_
+            )
+            assert str(actual) == expected
+
     def test_fetch_data(self):
         """
         DB Eng Specs (bigquery): Test fetch data