reduced slack functionality, higher ease of use. Database migration wip

news_fetch/utils_storage/migrations/migration.001.py

@@ -0,0 +1,67 @@
+from playhouse.migrate import *
+
+
+"""
+This migration assumes that downloads.db kept the exact same structure as before.
+messages.db should drop the table articlemodelreference in favor of a new field article in the thread-table
+Since each thread is constrained to exactly one article this makes the most sense.
+
+This migration assumes that messages.db gets a new field in the table thread:
+id  |   thread_ts | article_id
+
+We now need to migrate from the table articlemodelreference and then delete it.
+"""
+
+
+db = SqliteDatabase("/code/.dev/messages.db")
+migrator = SqliteMigrator(db)
+
+
+article_field = IntegerField(null=True)
+
+
+migrate(
+    migrator.add_column('thread', 'article_id', article_field),
+    # migrator.drop_column('some_table', 'old_column'),
+)
+
+
+
+# these are the old models, adapted to the migration
+
+class BaseModel(Model):
+    class Meta:
+        database = db
+
+class User(BaseModel):
+    user_id = CharField(default='', unique=True)   
+
+class Thread(BaseModel):
+    """The threads that concern us are only created if the messages that contain urls"""
+    thread_ts = FloatField(default = 0)
+    article_id = IntegerField(null=True)
+
+    
+class Message(BaseModel):
+    ts = FloatField(unique=True) #for sorting
+    channel_id = CharField(default='')
+    user = ForeignKeyField(User, backref="messages")
+    text = TextField(default='')
+    thread = ForeignKeyField(Thread, backref="messages", default=None)
+    file_type = CharField(default='')
+    perma_link = CharField(default='')
+    is_processed_override = BooleanField(default=False)
+
+
+class ArticleModelReference(BaseModel):
+    message = ForeignKeyField(Message, backref='article_model_references')
+    article_model_id = IntegerField(default = 0)
+
+
+
+
+for ref in ArticleModelReference.select():
+    ref.message.thread.article_id = ref.article_model_id
+    ref.message.thread.save()
+
+db.drop_tables((ArticleModelReference))