fix: allow functions to be default values (#252)

* docs: add examples for acceptance test

* fix: allow functions to be default values

* ci: Fix emulator version to 1.5.0

Because newer Spanner emulators have a bug aroud information schema.
They cannot return correct values for COLUMN_DEFAULT.

spanner> SELECT COLUMN_NAME, COLUMN_DEFAULT FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME="dynamic_items";
+---------------+--------------------+
| COLUMN_NAME   | COLUMN_DEFAULT     |
+---------------+--------------------+
| id            | NULL               |
| col_timestamp | CURRENT_TIMESTAMP( |
+---------------+--------------------+
2 rows in set (2.079298ms)

* build: use latest emulator version now that the related bug is fixed

* chore: added missing 'the'

* ci: add AR v7.0.5 to nightly tests

---------

Co-authored-by: nownabe <nownabe@users.noreply.github.com>
Co-authored-by: Knut Olav Løite <koloite@gmail.com>

.github/workflows/nightly-acceptance-tests-on-emulator.yaml

@@ -20,7 +20,7 @@ jobs:
       matrix:
         # Run acceptance tests all supported combinations of Ruby and ActiveRecord.
         ruby: [2.6, 2.7, 3.0, 3.1, 3.2]
-        ar: [6.0.0, 6.0.1, 6.0.2.2, 6.0.3.7, 6.0.4, 6.1.3.2, 6.1.4.7, 6.1.5.1, 6.1.6.1, 7.0.2.4, 7.0.3.1, 7.0.4]
+        ar: [6.0.0, 6.0.1, 6.0.2.2, 6.0.3.7, 6.0.4, 6.1.3.2, 6.1.4.7, 6.1.5.1, 6.1.6.1, 7.0.2.4, 7.0.3.1, 7.0.4, 7.0.5]
         # Exclude combinations that are not supported.
         exclude:
           - ruby: 3.0
@@ -59,6 +59,8 @@ jobs:
             ar: 7.0.3.1
           - ruby: 2.6
             ar: 7.0.4
+          - ruby: 2.6
+            ar: 7.0.5
     env:
       AR_VERSION: ${{ matrix.ar }}
     steps:

.github/workflows/nightly-unit-tests.yaml

@@ -12,7 +12,7 @@ jobs:
       matrix:
         # Run unit tests all supported combinations of Ruby and ActiveRecord.
         ruby: [2.6, 2.7, 3.0, 3.1, 3.2]
-        ar: [6.0.0, 6.0.1, 6.0.2.2, 6.0.3.7, 6.0.4, 6.1.3.2, 6.1.4.7, 6.1.5.1, 6.1.6.1, 7.0.2.4, 7.0.3.1, 7.0.4]
+        ar: [6.0.0, 6.0.1, 6.0.2.2, 6.0.3.7, 6.0.4, 6.1.3.2, 6.1.4.7, 6.1.5.1, 6.1.6.1, 7.0.2.4, 7.0.3.1, 7.0.4, 7.0.5]
         # Exclude combinations that are not supported.
         exclude:
           - ruby: 3.0
@@ -51,6 +51,8 @@ jobs:
             ar: 7.0.3.1
           - ruby: 2.6
             ar: 7.0.4
+          - ruby: 2.6
+            ar: 7.0.5
     env:
       AR_VERSION: ${{ matrix.ar }}
     steps:

CONTRIBUTING.md

@@ -48,10 +48,26 @@ Variable|Description|Comment
 `activerecord_tests`
 
 #### Example
+
 ```shell
 bundle exec rake acceptance[appdev-soda-spanner-staging,/home/Downloads/creds.json,activerecord_tests]
 ```
 
+You can also use the [Cloud Spanner emulator](https://cloud.google.com/spanner/docs/emulator).
+
+```shell
+docker run -d --rm -p 9010:9010 gcr.io/cloud-spanner-emulator/emulator
+export SPANNER_EMULATOR_HOST=localhost:9010
+bundle exec rake "acceptance[dummy-project,,dummy-instance,]"
+```
+
+If you want to run only one test, you can specify a test file.
+
+```shell
+bundle exec rake "acceptance[dummy-project,,dummy-instance,]" \
+  TEST=acceptance/cases/models/default_value_test.rb
+```
+
 ## Coding Style
 
 Please follow the established coding style in the library. The style is is
@@ -76,4 +92,4 @@ The rubocop settings depend on [googleapis/ruby-style](https://github.com/google
 
 Please note that this project is released with a Contributor Code of Conduct. By
 participating in this project you agree to abide by its terms. See
-[Code of Conduct](CODE_OF_CONDUCT.md) for more information.
+[Code of Conduct](CODE_OF_CONDUCT.md) for more information.

acceptance/cases/models/default_value_test.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "test_helpers/with_separate_database"
+
+module Models
+  class DefaultValueTest < SpannerAdapter::TestCase
+    include TestHelpers::WithSeparateDatabase
+
+    class DynamicItem < ActiveRecord::Base; end
+
+    def test_dynamic_default_values
+      connection.create_table :dynamic_items do |t|
+        t.column :col_timestamp, :datetime, default: -> { "CURRENT_TIMESTAMP()" }
+      end
+
+      item = DynamicItem.create!
+      item.reload
+      assert(item.col_timestamp)
+    end
+  end
+end

lib/activerecord_spanner_adapter/information_schema.rb

@@ -79,6 +79,14 @@ def table_columns table_name, column_name: nil
         column_name = row["COLUMN_NAME"]
         options = column_options[column_name]
 
+        default = row["COLUMN_DEFAULT"]
+        default_function = row["GENERATION_EXPRESSION"]
+
+        if /\w+\(.*\)/.match?(default)
+          default_function ||= default
+          default = nil
+        end
+
         Table::Column.new \
           table_name,
           column_name,
@@ -87,8 +95,8 @@ def table_columns table_name, column_name: nil
           allow_commit_timestamp: options["allow_commit_timestamp"],
           ordinal_position: row["ORDINAL_POSITION"],
           nullable: row["IS_NULLABLE"] == "YES",
-          default: row["COLUMN_DEFAULT"],
-          default_function: row["GENERATION_EXPRESSION"],
+          default: default,
+          default_function: default_function,
           generated: row["GENERATION_EXPRESSION"].present?
       end
     end