Npm run migrate - (Strange bug) - Foreign Key Constraint did not get generate after undoing @loopback/authentication implementation.

https://github.com/loopbackio/loopback-next/issues/5709

As per above, when I was doing code debugging with JSON Web token Authentication feature for the Todo and TodoList tutorial yesterday, and I realised that I couldn't get far in making the user and user credential models to perform database migraiton, I decided to undo this feature and wanted to roll back my local features and revert back my working Todo and TodoList models database migraiton.

When performing the steps from this page all over again - https://loopback.io/doc/en/lb4/todo-list-tutorial-sqldb.html

I found the foreign key constraints for my Todo/TodoList table/model did not generate in my postgres database.

I was puzzled why it happened until I ran the following

DEBUG=loopback:* npm run migrate

In the logs, I was expecting the following entries to appear in the logs:

loopback:connector:postgresql SQL: ALTER TABLE "public"."todo" ADD CONSTRAINT "fk_todo_todoListId" FOREIGN KEY ("todolistid") REFERENCES "public"."todolist"(id) ON DELETE NO ACTION ON UPDATE NO ACTION +1ms
loopback:connector:postgresql:data {"command":"ALTER","rowCount":null,"oid":null,"rows":[],"fields":[],"_types":{"_types":{"arrayParser":{},"builtins":{"BOOL":16,"BYTEA":17,"CHAR":18,"INT8":20,"INT2":21,"INT4":23,"REGPROC":24,"TEXT":25,"OID":26,"TID":27,"XID":28,"CID":29,"JSON":114,"XML":142,"PG_NODE_TREE":194,"SMGR":210,"PATH":602,"POLYGON":604,"CIDR":650,"FLOAT4":700,"FLOAT8":701,"ABSTIME":702,"RELTIME":703,"TINTERVAL":704,"CIRCLE":718,"MACADDR8":774,"MONEY":790,"MACADDR":829,"INET":869,"ACLITEM":1033,"BPCHAR":1042,"VARCHAR":1043,"DATE":1082,"TIME":1083,"TIMESTAMP":1114,"TIMESTAMPTZ":1184,"INTERVAL":1186,"TIMETZ":1266,"BIT":1560,"VARBIT":1562,"NUMERIC":1700,"REFCURSOR":1790,"REGPROCEDURE":2202,"REGOPER":2203,"REGOPERATOR":2204,"REGCLASS":2205,"REGTYPE":2206,"UUID":2950,"TXID_SNAPSHOT":2970,"PG_LSN":3220,"PG_NDISTINCT":3361,"PG_DEPENDENCIES":3402,"TSVECTOR":3614,"TSQUERY":3615,"GTSVECTOR":3642,"REGCONFIG":3734,"REGDICTIONARY":3769,"JSONB":3802,"REGNAMESPACE":4089,"REGROLE":4096}},"text":{},"binary":{}},"RowCtor":null,"rowAsArray":false,"_prebuiltEmptyResultObject":null} +4m

But that ALTER TABLE "public"."todo" ADD CONSTRAINT "fk_todo_todoListId" FOREIGN KEY ("todolistid") REFERENCES "public"."todolist"(id) ON DELETE NO ACTION ON UPDATE NO ACTION did not show up at all.

I teared down the database, recreated it again, run npm run migrate. I still ended with the same result.

I even restarted my Postgres DB and my machine, performed the steps all over again - the same problem persists.

Out of frustration, I decided to recreate my loopback app from scratch again, and peform the db models migration again - just to help to regain my sanity back ensuring that I didn't do anything else silly that caused all this unexplained confusion. Sure enough the foreigh key constraint creation through the npm run migrate works this time around.

Thus I want to understand this - does importing @loopback/authentication models and tables feature cause the foreign key constraint script migraiton to stop working all of the sudden? Or is it purely coincidental it could be a random environment issue?

Reproduce the Todo/TodoList SQL database tutorial migration after undoing the authentication implementation, using PostgreSQL and DEBUG=loopback:* npm run migrate. Compare the migration output with the expected foreign-key ALTER TABLE statement in the issue. Done means determining why the constraint is omitted, or narrowing the failure to a reproducible environment or setup difference.