Add in an async task to migrate the data over

awx/main/models/__init__.py

@@ -3,6 +3,7 @@
 
 # Django
 from django.conf import settings  # noqa
+from django.db import connection
 from django.db.models.signals import pre_delete  # noqa
 
 # AWX
@@ -99,6 +100,58 @@
 User.add_to_class('accessible_objects', user_accessible_objects)
 
 
+def convert_jsonfields():
+    if connection.vendor != 'postgresql':
+        return
+
+    # fmt: off
+    fields = [
+        ('main_activitystream', 'id', (
+            'deleted_actor',
+            'setting',
+        )),
+        ('main_job', 'unifiedjob_ptr_id', (
+            'survey_passwords',
+        )),
+        ('main_joblaunchconfig', 'id', (
+            'char_prompts',
+            'survey_passwords',
+        )),
+        ('main_notification', 'id', (
+            'body',
+        )),
+        ('main_unifiedjob', 'id', (
+            'job_env',
+        )),
+        ('main_workflowjob', 'unifiedjob_ptr_id', (
+            'char_prompts',
+            'survey_passwords',
+        )),
+        ('main_workflowjobnode', 'id', (
+            'char_prompts',
+            'survey_passwords',
+        )),
+    ]
+    # fmt: on
+
+    with connection.cursor() as cursor:
+        for table, pkfield, columns in fields:
+            # Do the renamed old columns still exist?  If so, run the task.
+            old_columns = ','.join(f"'{column}_old'" for column in columns)
+            cursor.execute(
+                f"""
+                select count(1) from information_schema.columns
+                where
+                  table_name = %s and column_name in ({old_columns});
+                """,
+                (table,),
+            )
+            if cursor.fetchone()[0]:
+                from awx.main.tasks.system import migrate_jsonfield
+
+                migrate_jsonfield.apply_async([table, pkfield, columns])
+
+
 def cleanup_created_modified_by(sender, **kwargs):
     # work around a bug in django-polymorphic that doesn't properly
     # handle cascades for reverse foreign keys on the polymorphic base model

awx/main/tasks/system.py

@@ -2,6 +2,7 @@
 from collections import namedtuple
 import functools
 import importlib
+import itertools
 import json
 import logging
 import os
@@ -14,7 +15,7 @@
 
 # Django
 from django.conf import settings
-from django.db import transaction, DatabaseError, IntegrityError
+from django.db import connection, transaction, DatabaseError, IntegrityError
 from django.db.models.fields.related import ForeignKey
 from django.utils.timezone import now, timedelta
 from django.utils.encoding import smart_str
@@ -48,6 +49,7 @@
     SmartInventoryMembership,
     Job,
     HostMetric,
+    convert_jsonfields,
 )
 from awx.main.constants import ACTIVE_STATES
 from awx.main.dispatch.publish import task
@@ -86,6 +88,11 @@ def dispatch_startup():
     if settings.IS_K8S:
         write_receptor_config()
 
+    try:
+        convert_jsonfields()
+    except Exception:
+        logger.exception("Failed json field conversion, skipping.")
+
     startup_logger.debug("Syncing Schedules")
     for sch in Schedule.objects.all():
         try:
@@ -129,6 +136,52 @@ def inform_cluster_of_shutdown():
         logger.exception('Encountered problem with normal shutdown signal.')
 
 
+@task(queue=get_task_queuename)
+def migrate_jsonfield(table, pkfield, columns):
+    batchsize = 10000
+    with advisory_lock(f'json_migration_{table}', wait=False) as acquired:
+        if not acquired:
+            return
+
+        from django.db.migrations.executor import MigrationExecutor
+
+        # If Django is currently running migrations, wait until it is done.
+        while True:
+            executor = MigrationExecutor(connection)
+            if not executor.migration_plan(executor.loader.graph.leaf_nodes()):
+                break
+            time.sleep(120)
+
+        logger.warning(f"Migrating json fields for {table}: {', '.join(columns)}")
+
+        with connection.cursor() as cursor:
+            for i in itertools.count(0, batchsize):
+                # Are there even any rows in the table beyond this point?
+                cursor.execute(f"select count(1) from {table} where {pkfield} >= %s limit 1;", (i,))
+                if not cursor.fetchone()[0]:
+                    break
+
+                column_expr = ', '.join(f"{colname} = {colname}_old::jsonb" for colname in columns)
+                # If any of the old columns have non-null values, the data needs to be cast and copied over.
+                empty_expr = ' or '.join(f"{colname}_old is not null" for colname in columns)
+                cursor.execute(  # Only clobber the new fields if there is non-null data in the old ones.
+                    f"""
+                    update {table}
+                      set {column_expr}
+                      where {pkfield} >= %s and {pkfield} < %s
+                        and {empty_expr};
+                    """,
+                    (i, i + batchsize),
+                )
+                rows = cursor.rowcount
+                logger.debug(f"Batch {i} to {i + batchsize} copied on {table}, {rows} rows affected.")
+
+            column_expr = ', '.join(f"DROP COLUMN {column}_old" for column in columns)
+            cursor.execute(f"ALTER TABLE {table} {column_expr};")
+
+        logger.warning(f"Migration of {table} to jsonb is finished.")
+
+
 @task(queue=get_task_queuename)
 def apply_cluster_membership_policies():
     from awx.main.signals import disable_activity_stream