Cascading Delete Tags (#201)

* initial commit

* update cascading delete

* address PR comments

* update db

backend/app/models/log_record_tags.py

@@ -11,7 +11,7 @@ class LogRecordTag(db.Model):
     log_record_id = db.Column(
         db.Integer, db.ForeignKey("log_records.log_id"), nullable=False
     )
-    tag_id = db.Column(db.Integer, db.ForeignKey("tags.tag_id"), nullable=False)
+    tag_id = db.Column(db.Integer, db.ForeignKey("tags.tag_id", ondelete='CASCADE'), nullable=False)
 
     def to_dict(self, include_relationships=False):
         # define the entities table

backend/app/services/implementations/tags_service.py

@@ -1,5 +1,6 @@
 from ..interfaces.tags_service import ITagsService
 from ...models.tags import Tag
+from ...models.log_record_tags import LogRecordTag
 from ...models import db
 
 
@@ -26,9 +27,13 @@ def get_tags(self):
             raise postgres_error
 
     def delete_tag(self, tag_id):
-        deleted_tag = Tag.query.filter_by(tag_id=tag_id).update({"status": "Deleted"})
-        if not deleted_tag:
-            raise Exception("Tag with id {tag_id} not found".format(tag_id=tag_id))
+        tags_to_delete = Tag.query.filter_by(tag_id=tag_id).first()
+        if not tags_to_delete:
+           raise Exception(
+               "Log record with id {log_id} not found".format(log_id=log_id)
+               )
+        tags_to_delete.log_records = []
+        db.session.delete(tags_to_delete)
         db.session.commit()
 
     def update_tag(self, tag_id, updated_tag):

backend/migrations/versions/117790caec65_.py

@@ -0,0 +1,32 @@
+"""empty message
+
+Revision ID: 117790caec65
+Revises: 8b5132609f1f
+Create Date: 2023-11-16 01:53:04.353305
+
+"""
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+
+# revision identifiers, used by Alembic.
+revision = '117790caec65'
+down_revision = '8b5132609f1f'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    with op.batch_alter_table('tags', schema=None) as batch_op:
+        batch_op.drop_column('status')
+
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    with op.batch_alter_table('tags', schema=None) as batch_op:
+        batch_op.add_column(sa.Column('status', postgresql.ENUM('Deleted', 'Active', name='status'), autoincrement=False, nullable=False))
+
+    # ### end Alembic commands ###