diff --git a/arkindex/dataimport/migrations/0008_add_gitref.py b/arkindex/dataimport/migrations/0008_add_gitref.py
index 2a17edaf8eaf577381c26f86b752f5d7b55d941e..1ab9b71b2ffa0da13a4d2bb00c7c575d9eb687f3 100644
--- a/arkindex/dataimport/migrations/0008_add_gitref.py
+++ b/arkindex/dataimport/migrations/0008_add_gitref.py
@@ -17,8 +17,9 @@ def migrate_git_refs(apps, schema_editor):
which case the GitRef object is linked to the latest version returned by the default
DB order. These values will be updated later when the GitLab webhook will be triggered.
"""
+ db_alias = schema_editor.connection.alias
Revision = apps.get_model('dataimport', 'Revision')
- for rev in Revision.objects.filter(ref__isnull=False):
+ for rev in Revision.objects.using(db_alias).filter(ref__isnull=False):
ref = rev.repo.refs.filter(name=rev.ref).first()
if ref:
ref.revision = rev
diff --git a/arkindex/documents/migrations/0006_region_fk.py b/arkindex/documents/migrations/0006_region_fk.py
index 01e538b2982f760ad6e51b51eaa799a8e8fe2a71..fdb8f4e27150c72d1031f51b2c28a4208bd7c450 100644
--- a/arkindex/documents/migrations/0006_region_fk.py
+++ b/arkindex/documents/migrations/0006_region_fk.py
@@ -6,9 +6,11 @@ def check_m2m(apps, schema_editor):
Ensure the RegionElement many-to-many relationship only has one
element per region, making it possible to turn it into a foreign key.
"""
+ db_alias = schema_editor.connection.alias
RegionElement = apps.get_model('documents', 'RegionElement')
duplicates = RegionElement \
.objects \
+ .using(db_alias) \
.values('region_id') \
.annotate(count=models.Count('id')) \
.filter(count__gt=1)
diff --git a/arkindex/project/config.py b/arkindex/project/config.py
index 31439c5e80381468fdda01190847ca05733de619..74e6596029e60749d42311661c40b41a337b6050 100644
--- a/arkindex/project/config.py
+++ b/arkindex/project/config.py
@@ -38,6 +38,13 @@ def get_settings_parser(base_dir):
database_parser.add_option('user', type=str, default='devuser')
database_parser.add_option('password', type=str, default='devdata')
+ replica_parser = database_parser.add_subparser('replica', default=None)
+ replica_parser.add_option('name', type=str, default=None)
+ replica_parser.add_option('host', type=str, default=None)
+ replica_parser.add_option('port', type=int, default=None)
+ replica_parser.add_option('user', type=str, default=None)
+ replica_parser.add_option('password', type=str, default=None)
+
email_parser = parser.add_subparser('email', default=None)
email_parser.add_option('host', type=str)
email_parser.add_option('port', type=int)
diff --git a/arkindex/project/routers.py b/arkindex/project/routers.py
new file mode 100644
index 0000000000000000000000000000000000000000..6caccbe1a6b5b5ea54112afdcb8e484251df8be6
--- /dev/null
+++ b/arkindex/project/routers.py
@@ -0,0 +1,27 @@
+class PrimaryReplicaRouter:
+ def db_for_read(self, model, **hints):
+ """
+ Reads go to the read-only replica.
+ """
+ return 'replica'
+
+ def db_for_write(self, model, **hints):
+ """
+ Writes always go to primary.
+ """
+ return 'default'
+
+ def allow_relation(self, obj1, obj2, **hints):
+ """
+ Relations between objects are allowed if both objects are in the primary/replica pool.
+ """
+ db_list = ('default', 'replica')
+ if obj1._state.db in db_list and obj2._state.db in db_list:
+ return True
+ return None
+
+ def allow_migrate(self, db, app_label, model_name=None, **hints):
+ """
+ All migrations should only run on the primary.
+ """
+ return db == 'default'
diff --git a/arkindex/project/settings.py b/arkindex/project/settings.py
index 7a02f85bccad020a4dd3a97f55f4b7841dbee304..a196372ca931f74d305f7ae8c5ac6779983f1576 100644
--- a/arkindex/project/settings.py
+++ b/arkindex/project/settings.py
@@ -44,17 +44,32 @@ ALLOWED_HOSTS = conf['allowed_hosts']
# Docker container name resolution
ALLOWED_HOSTS += ['127.0.0.1', 'localhost', 'backend', 'ark-backend']
+
# Database
-DATABASES = {
- 'default': {
+def _conf_to_django_db(config):
+ "Turn a YAML database config into a Django database config"
+ return {
'ENGINE': 'django.db.backends.postgresql',
- 'NAME': conf['database']['name'],
- 'USER': conf['database']['user'],
- 'PASSWORD': conf['database']['password'],
- 'HOST': conf['database']['host'],
- 'PORT': conf['database']['port'],
+ 'NAME': config['name'],
+ 'USER': config['user'],
+ 'PASSWORD': config['password'],
+ 'HOST': config['host'],
+ 'PORT': config['port'],
}
-}
+
+
+_primary_db = _conf_to_django_db(conf['database'])
+DATABASES = {'default': _primary_db}
+
+if conf['database']['replica'] is not None:
+ # Make the replica's options default to the primary's
+ _replica_db = _conf_to_django_db(conf['database']['replica'])
+ for key, value in _primary_db.items():
+ if not _replica_db.get(key):
+ _replica_db[key] = value
+
+ DATABASES['replica'] = _replica_db
+ DATABASE_ROUTERS = ['arkindex.project.routers.PrimaryReplicaRouter']
# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = ARKINDEX_ENV == 'dev'
diff --git a/arkindex/project/tests/config_samples/defaults.yaml b/arkindex/project/tests/config_samples/defaults.yaml
index 661df06079a42ab49418bcca77066a5c38a0b705..ac3f99492800a64d1a1f1907471a4e3b1093a370 100644
--- a/arkindex/project/tests/config_samples/defaults.yaml
+++ b/arkindex/project/tests/config_samples/defaults.yaml
@@ -20,6 +20,7 @@ database:
name: arkindex_dev
password: devdata
port: 9100
+ replica: null
user: devuser
docker:
tasks_image: registry.gitlab.com/arkindex/tasks
diff --git a/arkindex/project/tests/config_samples/override.yaml b/arkindex/project/tests/config_samples/override.yaml
index acd4a45b4aa182aded8f60934b195404b5cce79a..8885614b2ae1f89b1ff4077c69ea9649569c92dd 100644
--- a/arkindex/project/tests/config_samples/override.yaml
+++ b/arkindex/project/tests/config_samples/override.yaml
@@ -22,6 +22,12 @@ database:
name: arkindex_db
password: hunter2
port: 9123
+ replica:
+ host: ghost
+ name: arkindex_db2
+ password: password
+ port: 1
+ user: postgres
user: littlebobbytables
docker:
tasks_image: registry.gitlab.com/arkindex/stonks
diff --git a/arkindex/users/migrations/0001_initial.py b/arkindex/users/migrations/0001_initial.py
index 51dbb2b9c6cba633a92708b0cf51dd6c95dbfa3f..12b91880531661c9e93b54972515a77002fe3d6e 100644
--- a/arkindex/users/migrations/0001_initial.py
+++ b/arkindex/users/migrations/0001_initial.py
@@ -14,8 +14,9 @@ def create_internal_group(apps, schema_editor):
In the event of a migrations reset, this should be kept to make deployments simpler.
"""
+ db_alias = schema_editor.connection.alias
Group = apps.get_model('auth', 'Group')
- Group.objects.create(id=settings.INTERNAL_GROUP_ID, name='Internal')
+ Group.objects.using(db_alias).create(id=settings.INTERNAL_GROUP_ID, name='Internal')
class Migration(migrations.Migration):
diff --git a/arkindex/users/migrations/0002_userscope.py b/arkindex/users/migrations/0002_userscope.py
index 646520fb760fbc1e3bfe9aec4e06d1144ab16b35..09e37d18b2984c143d4fee21cf3dea1a556d3652 100644
--- a/arkindex/users/migrations/0002_userscope.py
+++ b/arkindex/users/migrations/0002_userscope.py
@@ -8,11 +8,12 @@ import enumfields.fields
def add_scopes(apps, schema_editor):
+ db_alias = schema_editor.connection.alias
User = apps.get_model('users', 'User')
UserScope = apps.get_model('users', 'UserScope')
- UserScope.objects.bulk_create([
+ UserScope.objects.using(db_alias).bulk_create([
UserScope(user=user, scope=scope)
- for user in User.objects.all()
+ for user in User.objects.using(db_alias).all()
for scope in (Scope.CreateIIIFImage, Scope.UploadS3Image)
])